INSIDE…

Showcase Hsg Seminar 9

Athletes' Village 12

BRE Innovation Park 14

Green Energy Awards 18

Return to 'Edenhope' 19

All-Energy 2014 21

Eurosun 2014 22

Sun-Spots 24

SunTimesScottish Solar Energy Group Newsletter Autumn 2014 Issue 33

SSEG’s involvement in this initiative aimed at the Scottish Government, as well as commercial and academic players, comes due to the multiple hats of our Chairperson Dr Anne-Marie Fuller – two of these being Technology Business Development Executive of both the Scottish Institute for Solar Research (SISER) and the Energy Technology Partnership (ETP).

So SSEG and AES Solar became part of the organising team for

two key events, a full-day Seminar and Workshop held at the Scottish Universities Insight Institute (SUII) at the University of Strathclyde, Glasgow, on the 24th October 2013, and a half-day conference at the Scottish Parliament, Edinburgh, on the 19th May 2014.

TRANSFORMING SCOTLAND WITH SOLAR ENERGY

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Both of these events were coordinated by Anne-Marie’s colleague at the University of Edinburgh, Dr Neil Roberts, Director of SISER, and in-between the two Neil orchestrated feed-back from participants at the initial seminar, part of the process of steering the text for the output report ‘Solar Energy – A Viable Contributor to Renewables in Scotland’ – that was then disseminated at the Scottish Parliament.

SCOTTISH UNIVERSITIES INSIGHT INSTITUTE 24TH OCTOBER 2013

Neil and Anne-Marie had organised the autumn 2013 event with a line-up of six speakers in the

morning and five themed workshops in the afternoon. Neil both introduced the day and kicked off the morning with an overview of the German solar industry on behalf of Hans Josef Fell of the German Green Party. His introduction mentioned that the event was part of SUII Wellbeing Programme: “the Scottish Institute for Research in Economics is leading a knowledge exchange project around wellbeing and the economy”. He also mentioned the Scottish Government’s 2020 Renewable Route Map of 30th October 2012 with no strategy for solar, compared with Germany with 35.5% solar PV predicted (in pie format, with off-shore wind in 1st place at 406 TWh annually, and solar, perhaps surprisingly, in 2nd at 140 TWh); and informed that Scotland had some 85-90% of the solar resource in Germany.Moving on to his proxy presentation for Fell, Neil started with the German Green Party’s target of 100% renewable energy (23% by 2012), noting that Fell was no fan of nuclear (in any case being phased out), but that currently Germany was importing large quantities of fossil fuels – paradoxically, these enjoyed higher subsidies than renewables, and Germany was still exporting electricity. However, wind, biomass and PV are now all growing strongly, as a ‘job engine’ employing 380,000 now, including those in 586 Civic Energy Co-ops in 2011, and with 500,000 predicted by 2020. It was estimated that solar PV would constitute 35.5% renewable generation, and there was also a role for large-scale solar thermal district heating. German ‘Feed-In Tariff’ or FIT over 10 years (‘feed-in’ law dating from 2000) had been gradually reducing in parallel with tumbling prices, and was now moving to a stage where the incentive would no longer be needed. Part of the uptake had been from grassroots with new and small-medium co-ops. Neil concluded that, despite ‘wrong arguments’ – all the usual ones still trotted out in the UK – big utility companies feared for their business with 6% of electricity production lost in the last 6 years, and that hybrid power was required to balance fluctuations.Alan South, Head of Innovation at Solarcentury, then addressed solar market penetration around four sub-themes: History, Incentives and Regulation, Market Development and Future. He told us that there were already 50 companies in 1996, with Solarcentury founded in 1998 and their ‘solar roof-tile home’ dating from 1999. Ironically, the fastest growing sector in PV is unsubsidised – e.g. in Kenya. Alan also

noted that FIT, introduced to the UK in April 2010, was hated by economists as a ‘market distortion’; also running in parallel with Renewable Obligation Certificates (ROCs 2002-2017; with PV under ROCs rather than FIT from April 2012). Unfortunately it made, usually rich, home-owners even richer as an investment benefit and income generator; also citing ‘Solar for Free’, a 25-year lease on the airspace above the roof of a mortgaged house as having legal and/or contractual complications, and pondering the benefits to tenants where housing associations put solar on roofs and pocket the FIT. I am including a photo of renovated social housing with PV now installed in Milton, one of Glasgow’s most deprived areas, to illustrate Alan’s underlying question – what do the tenant’s get from it?

For the future, Alan noted the 2014-2020 ‘Contracts for Difference’ and was doubtful as to whether the target of all new homes to be ‘carbon zero’ by 2016 would be realised – in any case the definition of ‘carbon zero’ keeps changing to make it more achievable. On the positive side he cited the proposal for a 1.1 MWp PV installation at Blackfriars Bridge, London, a £7.3m investment with a predicted annual output of 900,0000 kWh (818 kWh/kWp) and an annual saving of 513,000 kg CO2 (DECC, Energy Investment Report April 2014, HM Government, URN: 14D/128); and several hundred ‘Solar 4 Schools’ as part of the Low Carbon Building Programme. He also gave some figures on two PV ‘solar farms’: Wilburton, Cambridge at 4.99 MWp (still micro-generation), with its annual output estimated at 4,555,000 kWh (913 kWh/kWp) and a CO2 saving of 2,355,000 kg; and Chediston Hall Solar Farm, Norfolk, at 12.4 MWp (Jan-March 2013) and 50,400 panels. He then highlighted the UK’s slow rate of PV-growth compared with EU neighbours; UK’s annual growth from 700-750 MWp during 2011 cf. Italy 9,000-12,500, Germany 7,500-24,700, Belgium 5,550-1,500 and Spain 4,000-4,200. However, it appeared that the UK had accelerated PV installation significantly from 2011-2013, up by roughly 200% each year to 3 GWp (initial FIT surge including the 0.6 MW PV-farm at Dalkeith); and requiring an annual average increase of 105% to reach the target of 22 GWp by 2020. Finally, Alan referred to challenges such as availability of economic grid connections (e.g. in East Anglia) and

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achieving ‘grid parity’: “although significant cost reductions have occurred in recent years, the costs of the basic materials are relatively high and the level of cost reduction that is feasible to achieve grid parity is still very uncertain, particularly in areas with modest solar radiation like the UK” (DECC, ‘UK Solar PV Strategy Part 1: Roadmap to a Brighter Future’, Oct. 2013, URN 13D/251, p 17); while at the same time emphasising the positive role of companies such as ProxEnergy committed to providing innovative ‘smart grid solutions’ and of the Solar Trade Association (STA), with its 10 Commitments for solar farms. (http://www.solar-trade.org.uk/solarFarms.cfm)Ray Noble then followed Alan with a talk on the STA and the National Solar Centre. He started by mentioning historic landmarks for PV in the UK – the retrofit at the University of Northumbria (SSEG members with long memories may recall Nicola Pearsall’s January 1995 talk to us in Edinburgh when she confirmed switch-on as November 1994); and Sue Roaf’s 1995 Ecohouse in Oxford (Ecohouse: A Design Guide, first published 2001), reputedly the first UK PV roof, which also included solar thermal panels by George Goudsmit, AES Findhorn (now Forres). He then moved on to solar energy technologies: crystalline PV with some 90% of market share, with rear contact cells and 20% efficiency ‘on their way’; thin-film PV, with amorphous ‘come and gone’, CdTe and CIGS in production, organic thin-film appearing and screen-printed electronics in development; and solar thermal due to be boosted by the Renewable Heat Incentive (RHI) in 2014, with the prospect of new product development. Ray then mentioned the Scottish Government’s Solar Strategy Road Map, with (as noted above by Alan South) at least 20 GWp ‘still on the agenda’, but apparently with only half that possible to be grid-connected at present. In relation to the grid he expanded that storage and smart grids have ‘catapult’ status; that it is proposed to accept ‘deemed’ planning permission up to 5 MWp installations from the present 50 kWp; and OFGEM (Office of Gas and Electricity Markets) registration is to be speeded up. He also informed that the Microgeneration Certification Scheme (MCS) defines three zones of annual output expectation in kWh/kWp: zone 14 @ 835; zone 15 @ 944; zone 16 @ 877 (more on the vagaries of kWh/kWp as a measure of output later). In terms of market penetration for PV, Ray told us that prices have fallen faster than FIT reduction, that for ‘building-added’ systems social housing was a key priority, there were opportunities for PV canopies over parking areas, and that ‘solar fields’ were expected to grow rapidly, with grazing or wild meadows with associated biodiversity still feasible. Ray concluded by mentioning that the DECC had asked the National Solar Centre (NSC), now located at the Eden Project, to produce a Good Practice Guide and that David King (energy adviser to the previous Labour Government) predicted a target of 25% share of the World’s energy supply by solar by 2025. But on the web, it is given as 10% by 2025 and 25% by 2030.

(Note that the Wikipedia definition of energy supply is in two parts: “Energy supply is the delivery of fuels or transformed fuels to point of consumption. It potentially encompasses the extraction, transmission, generation, distribution and storage of fuels.” The first sentence implies a net supply to a consumer, where, for example, the only significant reduction to delivery from roof mounted panels occurs at the inverter. But the second sentence indicates potential for remotely generated supply as a gross term containing many losses, commonly known as primary energy. Another ubiquitous term energy capacity refers to the normal maximum output of a generating source, which may be multiplied by a capacity factor or load factor to give the average expected output of the generating source over time, which is inevitably greater than the delivered energy to points of use; and, in its turn, delivered energy is more than net consumer demand, depending on efficiency of appliances. In other words, we need to be very careful not to compare apples with pears or oranges when confronted with energy data.)

After coffee Prof Gareth Harrison from the Institute of Energy Systems at the University of Edinburgh addressed the issue of grid integration, storage and balancing with other renewables. Suffice to say such issues are complicated, in particular relative to the supply-demand dichotomy of solar PV (assuming grid-connected): supply dependent on day length (brief in central winter period), solar geometry, climatic characteristics and day-to-day vagaries of weather; before we come to site obstructions, constraints on optimum orientations and tilts, and financial or bureaucratic obstacles; demand varying from peak daytime workplace to peak domestic evening and some commercial and industrial nightshifts. Gareth indicated a role for ‘portfolio effects’ from different sites to give a smoother pattern of supply, and smart electronic ‘demand matching’ (hopefully with Ray’s ‘catapult status’). All this is further complicated by the need to ‘inject’ to the grid when the demand is low, also bearing in mind that voltages are strictly regulated by statute. Gareth concluded that, despite the challenges, PV would have an impact on networks.Previous SSEG Chairperson Elaine Morrison then stirringly shifted the agenda from physical science to social science with her topic ‘Rural Opportunities and Energy Security’, and emphasised at the outset: “Energy is a social issue.” She showed the structural, geographical and ideological aspects of injustice in an alliterative interlocking bubble diagram: pollution, profit and poverty, this applying geopolitically. Then she cited the DECC report ‘Energy Trends: June 2012’ (URN 12D/79B) in which the Summary, p 86, states: “The evidence from this analysis suggests that domestic PV installations are typically located in the more affluent, higher energy consuming households. This correlates with the additional findings that areas with a high proportion of detached housing, a low proportion of social housing and/or a low proportion of low value housing tend to have a higher amount of PV installations.” In other words, social housing gets

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the short end of the stick. The quote from the above DECC report cited by Elaine is not confined to rural housing, and since Glasgow’s peripheral areas may be understood as ‘villages’, I have included some photos that affirm these points – relatively up-market regeneration in Maryhill and Ruchill, where PV arrays by individual households are becoming quite common.

On the issue of energy security, Elaine went on to mention the heavy snowstorms of March 2013, plus the energy company price hikes (SSE first) of October 2013 – all this with health implications. In this regard, ‘fuel poverty’ (households spending more than 10% of their income, including benefits and income support) was up to 35% in rural communities (approx. 770,000 households; citing the Scottish House Condition Survey, published Nov. 2011), and 57% for those using solid fuel. Indeed rural Scotland

had a higher rate of poverty than urban Scotland, even though the Highlands had quite a high take-up of PV (in conformity to the 2012 DECC report above). Further, even though the numbers of reasonably energy-efficient dwellings had increased, so also had fuel poverty: “Insulation won’t do it alone.” This is partly due to increased levels of heat within better-insulated homes, partly due to increasing use of appliances and most significantly due to the hikes in the cost of each unit of energy. The first of the next two photos (in Glasgow’s Milton) indicates starkly from where most of the grid power comes, contrasting hugely with the second where limited size and over-shading is bound make the contribution from PV paltry relative to demand. It’s a case of ‘every little helps’!

However, upgraded housing in nearby Cadder, which relies solely on passive solar gain to mitigate demand for heat and is completely within the occupants’ control, appears to get a ‘yes’ vote!

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So Elaine posed the question as to what solar PV and thermal do to help matters, assuming energy savings are potentially big enough to make a difference. Firstly there are challenges to surmount. Presently FIT and RHI tend to exclude low-income groups or those with poor credit ratings, and modelling or predicting solar benefits is tricky due to demand variability – “people are so difficult!” Elaine wondered if we could not introduce changes to building regulations to make inclusion of solar systems mandatory, perhaps as part of heating replacements.Finally, Prof. Sue Roaf from the School of the Built Environment at Heriot Watt University gave a typically spirited and wide-ranging overview of what does happen compared with what could happen given present socio-political systems and the capacity of the eco-system. Clearly solar energy is integral to the latter and Sue stressed the need for greater take-up of ‘building-integrated’ or ‘building-added’ solar, the latter placing greater stress on retrofit (and allowing for one understanding of ‘integrated’ as constituting part of the weatherproof skin, rather than being placed on top of it). Ranging round the globe, Sue indicated the power of community activism – 4 million people on the street in Sao Paulo due to a bus-fare hike (could it really be that many? … but I also recall a similar near-revolution in Heidelberg due to a tram-fare hike in 1976). She then went on to promote the International Solar Cities Initiative (ISCI), formally inaugurated in Daegu, South Korea in 2004 and followed by a second in Oxford 2006 (I met Sue at the 2003 ISES Congress in Gothenburg drumming up backing for this; and, of course, Elaine Morrison was for many years afterwards leading Dundee Solar City with the help of other SSEG stalwarts such as Rory O’Riordan). Finally Sue noted that China now produces 45% of Global PV and stressed the role of ‘solar champions’, citing Josep Puig in Barcelona as an example.

After our networking lunch, we moved into a series of three workshop sessions, chosen from a set of five topic: Scottish market development for BAPV (building added PV); Solar Cities and societal benefit; Emerging technologies and new markets; Rural opportunities and rural energy security; and Grid integration, storage and balance with other renewables. These seemed to be lively affairs, with the key points arising from them all summarised in the final feedback session, but of course missing much of the detail.To give an example of one issue that arose and remained unreported, I had an interesting conversation with Sue Roaf about indoor air quality (IAQ) during the ‘rural opportunities’ workshop. That subject might seem odd in a workshop focussed on solar energy potential, but utilising this natural resource is inextricably bound up with energy efficiency, and rates, means and quality of ventilation follow naturally from that. Sue asserted that the longstanding benchmark value of no more than 1,000 parts/million (ppm) for CO2 was a myth, and quoted people in Portugal who are quite content at 3,500 ppm. I rejoined that it is not of course the concentration of CO2 itself that is the issue, but the ‘bad company’ that normally accompanies values above that benchmark, and that such pollutants could involve health risk to vulnerable sections of the population. Given that Portugal may have very clean air, and perhaps the houses in question were free from materials with undesirable off-gassing characteristics, absolute levels of moisture are nevertheless likely to be an issue at 3,500 ppm as moisture tends to track CO2 quite closely. And since one might expect quite warm temperatures to occur inside, say 27ºC at 55% relative humidity (RH), this would correspond with a vapour pressure of 1.94 kPa – indicating an overly humid atmosphere even though the RH seems quite modest. This would tend to feel cloyingly stuffy, corresponding with about 1.75 l/s air supply per person (UK minimum standard 8 l/s, which corresponds with 1,000 ppm CO2). Even so, it may be experienced as relatively unproblematic for those acclimatised to it, unless they are sensitive to a particular pollutant – for example, aldehydes from certain materials that become more concentrated with increasing moisture. But if the temperature were to drop even by 3 degrees overnight in such a Portuguese bedroom to 24ºC, whilst the ventilation rate, occupancy and absolute moisture level remained constant, the RH would increase to 65%, which then puts the IAQ into a high risk area for excessive populations of dust mites. This would then pose a specific risk for asthmatics, children in particular.

PRESENTING THE VISION: SCOTTISH PARLIAMENT 19TH MAY 2014 Neil took the lead in organising and chairing this important half-day conference, with Anne-Marie by this time on maternity leave (happy outcome, Orla, SSEG's Fiona MacLennan as workshop scribe

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welcome to the world); the report for dissemination ‘Solar Energy – A Viable Contributor to Renewables in Scotland’ prepared by Iain Weir and Joginda Gagura of Optimat on behalf of SISER and SSEG, and with additional support for Elaine Morrison, George Goudsmit and myself from SSEG, not to mention funding from SUII.

Donald Jarvie, Head of Business, Scotland’s Futures Forum based at the Scottish Parliament and our host, introduced the morning. Donald emphasized the Forum’s thrust on ‘fresh thinking and new insights’, noting that it was non-party affiliated, its Board embracing MSPs of all political persuasions as well outsiders with specific expertise. (Editor’s note: MSPs were noticeable by their absence at this event, which had attracted mainly commercial and academic players in the solar firmament.) Donald then mentioned SUII, involving eight Scottish Universities,

and its Director Charlie Wood before introducing Neil Robertson as first speaker of the morning. Neil’s presentation summarised key aspects of the ‘Solar Vision for Scotland’ contained in the Vision document (to be emailed by SISER to all participants), having first sketched out its background, in particular the October 2013 event in Glasgow, noted key documents and dates relevant to where we are now: The December 2013 updated 2020 Routemap for Renewable Energy in Scotland, now includes a solar sectoral routemap, as opposed to no strategy for solar in 2012. Neil also mentioned an International Energy Agency (IEA) prediction published on the CleanTechna website on May 16th 2014 by Giles Parkinson, founding editor of RenewEconomy.com.au: “The International Energy Agency says solar energy – a combination of solar PV and concentrated solar thermal with storage – is likely to become the dominant source of energy across the world, accounting for more than 27 per cent of all electricity produced by 2050.” However, in the ‘now’ of Scotland, Neil noted that an abstract he had submitted to the All Energy conference in Aberdeen to outline the Vision Document had not been accepted – apparently because there was no suitable category for inclusion within the programme!At any rate the Introduction to the Vision Document ‘Solar Energy – A Viable Contributor to Renewables in Scotland’ cites the UK’s almost 4.5 GW installed PV capacity at March 2014 (a rapidly moving picture: cf. approximately 3.0 GWp reported by Alan South in October 2013); while Scotland had only 116 MW installed generating capacity at the end of 2013 (Scottish Renewable Energy Sector in Numbers, Scottish Renewables), and a target for 860 MW by 2020. However, looking optimistically to what was technically possible in Scotland (assuming some 25% of Scottish roof area facing in a generally southerly direction), Neil estimated 7 GW, generating approximately 5.6 TWh annually, or approximately one sixth of Scottish demand, assuming an average of 800 kWh/kWp. Given that total renewable energy capacity in Scotland at the end of 2013 was only some 6.5 GW, Neil’s optimism is clearly predicated well into the future. On the scope for solar thermal, Neil reported that although there had been a decline over the previous 3 years, the Renewable Heat Incentive (RHI) should provide a boost, especially given that a typical system yields some 40-50% of the domestic hot water (DHW) load annually. At the end of 2012, Scotland’s solar thermal capacity was estimated to be 28 MW, some 5% of Scotland’s renewable heat capacity, biomass having over one half and biomass/CHP one quarter (Renewable Heat in Scotland, Energy Savings Trust, 18th June 2013).Neil, like Elaine back in the October event, drew attention to the issue of fuel poverty, currently estimated as some 900,000 households in Scotland. A 2012-2013 review of 122 social housing tenants, 100 of whom were in Scotland, had concluded that solar PV “can make a valuable contribution to reducing social housing tenants’ fuel bills and alleviating fuel

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poverty.” (‘Using Solar PV to Tackle Fuel Poverty’, Changeworks for Eaga Charitable Trust, Feb. 2014). Sue Roaf had also been involved in studies that indicated that Dundee could eliminate fuel poverty with the help of solar PV, and Neil mentioned other projects where monitoring had shown PV to perform well, citing the Sporsnis community/sports facility in Ness at the northwest extremity of the Isle of Lewis.

Such individual projects indicated a need for an expanded programme of development and monitoring of sustainable buildings in the context of a longer-term roadmap; this being the responsibility of a number of players – government, academia, etc. Neil concluded with five strands required in the development of a common vision: to recognise the huge growth in PV anticipated; to plan to maximise Scottish benefits; to define and confirm an action plan; to identify solar champions; and to establish a solar leadership group.The next speaker, Dr Finlay Colville for Solarbuzz, gave an enthusiastic wander around PV solar fields, comparing market trends globally with the UK situation. Confirming the UK’s figure of 4.5 GW capacity at the end of March 2014 (see above) from ‘virtually nothing’ in 2010, he told us that at the same time globally approximately 50% was ground-mounted (i.e. solar fields, the key driver to expansion), 25% large non-domestic roofs, and the remaining

25% residential on roofs or related small arrays. He also informed that the annual European demand for PV had peaked in 2011 at around 19 GW, whereas the capacity envisaged globally was currently 50 GW (April 2014). Apparently this year the expansion in the UK was foremost in Europe, having overtaken Germany. However, withdrawing incentives like FIT will lead to a downturn in demand, initially residential in the UK, but now undoubtedly ground-source with fields > 5 MW leading the way. On the other hand, apparently DECC wishes to limit large-scale solar farms – there are now 363 PV farms in the UK, with the biggest in Scotland currently only 600 kW at Dalkeith, compared with one of 40 MW in Oxfordshire. Although it was hard to generate a large-scale rooftop market, there was clearly much scope in Scotland for more and bigger solar farms.The aim of my presentation was to take the topic of solar energy back to architecture in all of its applications, including passive solar heating and day-lighting as well as both thermal and electrical active methods, either building-integrated or building-added. I used ‘Solar Architecture in Cool Climates’ (2005, Earthscan, the book I wrote with Kerr MacGregor) as my starting point: two early projects, passive solar new-build council housing in Stornoway in the 1980s and the retrofit European demonstration project at Easthall, Glasgow in the early 1990s; then more recent ones such as ‘Easthall descendants’ at Cadder in Glasgow, 2010, with Windoor glazed-in balconies, Oban-based CP Architects’ 2008 Fyne Homes housing on the island of Gigha with their roofs of Velux windows and thermal solar panels, Gokay Deveci’s first Scottish Passivhaus at Dunoon with its roof-integrated Velux collectors-window array, 2010, and John Gilbert’s 2013 East Whins housing with its sun-porches and AES thermal collectors at Findhorn. I then shifted focus to another thermal passive solar technology, transparent insulation (TI): starting with the Strathclyde student residences of the late 1980s (another European demonstration project in Glasgow), before coming to a much smaller, and more successful, late 1990s house at Herisau near Zurich by architect Peter Dransfeld, and then a 2008 manifestation of TI in a large 2008 social housing scheme in Winterthur by Dietrich Schwarz – using a product GlassXcrystal, a translucent glazing system incorporating salt-hydrate phase-change thermal storage (see SunTimes 29). This last product of course allowed more daylight into the interior, hence displacing the need for artificial lighting, at the same time limiting heat build-up during the day. Moreover, although intrinsically expensive as one might expect with a U-value of 0.48 W/m2K, it represented a business message for Scottish architects in that Dietrich Schwarz was also the CEO of its manufacturing company. Finally, I moved back to Scotland with a number of case studies where active solar systems have been aesthetically integrated with buildings. The first two have a wider solar-sustainability agenda, and had also been nominated for the 2013 Kerr MacGregor

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Memorial Award (see later article p18). These were the 2008 Sporsnis Community and Sports Centre in Ness, Isle of Lewis mentioned earlier by Neil, and the 2011 Banff and Buchan College retrofit in Fraserburgh, the former by Gordon Anderson of Anderson Associates in Stornoway and the latter by Lucy Addison of CDA in Glasgow (see SunTimes 32). At Sporsnis, Gordon had designed a ‘roofscape’ that included two major rows of roof-windows, a 10.2 kWp PV array and a solar thermal array. Not only had the PV been monitored over 4 years, delivering an impressive 126 kWh/m2 net PV collecting surface, the roof windows delivered daylight to both the main hall and peripheral galleries and facilities at two levels. This is not to mention under-floor heating served by ground-source heat pumps and additional electricity generated by wind. The solar collectors for both Banff and Buchan College and Sporsnis,

were also visually discreet, the photographs of those at Spornis only possible from the higher ground near the site entrance. On the other hand, those at all the next four projects shown are a prominent part of the architectural presence, indeed part of the commercial solar branding in the following two cases. The pragmatic rooftop retrofit of the Muir Group HQ in Inverkeithing in Fife was highly visible from the adjacent trunk road, while the Survey Solutions’s HQ at Bilston Glen, Midlothian was an intrinsic part of the building’s striking pyramidal form, a highlight in a dreary industrial park (again, see SunTimes 32 for both projects). Then, the arrays of both RMJM’s 2014 Athletes’ Village at Dalmarnock in Glasgow and Andy Swales and Sarah Eno’s self-build, autonomous home ‘Edenhope’ near Selkirk in the Borders (see articles later in this issue) were also visually well-integrated with respective roofs – in a similar manner to those of the solar thermal arrays shown earlier in my presentation. However, to avoid complacency and to further instil the need for a greater ‘solar vision’ for Scotland, I ended with a slide of the 1998 ‘Energiebalanswoning’ in Amersfoort, Netherlands, with its fully integrated passive solar and active solar thermal and PV – visited by SSEG in August 2003, and described in SunTimes 23.

Postscript: on the way back from our rather gloomy, artificially lit venue on the ground floor of the Scottish Parliament, I stopped off at Benson & Forsyth’s 1998 Museum of Scotland, where the sunlit main atrium space lifted my solar spirits.

Sporsnis viewing gallery

Sporsnis direct and borrowed daylight

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Julie initially reminded the audience that the Showcase included 27 dwellings, employing 10 different construction systems (‘modern methods of construction’ or MMC) by various housing providers; and completed in April 2012, they had been open to the public for three weeks. She added that tenants appeared to be happy overall. Kingdom’s commitment to monitoring had particular concerns such as air-tightness, as well as the performance of the energy-efficient construction over two full years compared with predictive analysis (some comment on this in SunTimes 32). Julie told us that the Stage 1 Monitoring Study Report was due to be published shortly, running to 200 or so pages.Julio started by outlining the content of this report, essentially the monitored results for the first year of occupation: introduction; building performance per ‘block’; renewable energy performance; conclusions. An architect by background, he also told us a little about ISC, this led by Prof Sean Smith in tandem with Prof John Currie of the Scottish Energy Centre at Napier (the latter also at 42 Colinton Road, some way west of the main Morningside campus); and that ISC specialised in environmental auditing and modelling.As one might expect, given the evidence of other projects, there

was a considerable gap between measured performance and the SAP-based predictions (for regulated energy); and Julio told us that the predictions had all been recalculated using ‘in situ’ data. Misia Jack in the audience commented at this point that social behaviour was bound to be influential for the measured data compared with SAP-based assumptions. Accepting the significance of this for heating and ventilating controls, Julio also commented that the study had looked at performance gaps that are independent of influence by occupants: measured ‘in situ’ U-values; air-tightness testing; and a thermographic survey internally and externally. The study also looked at the ‘design aspirations’ of services where occupants do interact with controls. Overall the generic methodology for monitoring and testing complied with CIBSE TM22 (2006). In order for SunTimes readers to make sense of the detailed results that Julio then disseminated, they would really require the information-pack that we had been given, with coding for blocks and construction types; also in the ‘Housing Innovation Showcase 2012 Building Performance Evaluation Phase 1 – Part One’ report, now received. This sets out to look at SAP validation and an early occupation study of a sample

SSEG planned this meeting on 24th February 2014 specifically as a follow-up to its visit to the Showcase demonstration by Kingdom Housing Association in Dunfermline at the end of January 2013 (SunTimes 32, pp 30-31). In the meantime, Julie Watson of Kingdom HA had overseen the monitoring undertaken by the Institute for Sustainable Construction (ISC) at Napier University, and undertaken there by Julio Bros-Williamson as a part of his PhD research.

DUNFERMLINE SHOWCASE HOUSING SEMINAR

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of homes in the development, and hence it does not go as far as other data Julio reported to us – in particular measured energy consumed, which includes that by electrical appliances (excluded from SAP predictions as unregulated). Quoting Julio from a recent e-mail: “… loggers covered total consumption of gas, electricity and in some a heat meter or a renewable source. The electrical consumption that we obtained for the whole year included lighting, pumps, fans, cooking (most had electric oven, but also hobs) and appliances or un-controlled energy. Sadly we couldn’t sub-meter electrical energy to define this monitoring. This will be the case in 4 properties in our Phase II work already in place.” Nevertheless, the combination of data in the other houses, with most using gas for space heating and hot water, should enable the second report to give a reasonable estimate of consumption by appliances to be deducted from the total to give a ‘regulated energy’ comparator to the ‘as-built’ SAP figures. The measure of gross consumption in the first report is for August 2012, as residents first settled in (later “deemed to be inaccurate as many figures were not given as monthly figures”). There are two sets of SAP figures in the report, ‘as-designed and ‘as-built’ for each plot; but the former tabulated results “differ marginally from the originally submitted SAP results as obtaining exact figures when re-calculating design predictions was not achieved”, while the latter gives SAP results “using as-built values

for component U-values and Air tightness”, and where floor U-values were absent in some instances. The report also notes additional anomalies between design-stage information and the as-built reality – e.g. wrong orientation, changes to window sizes, altered specification of heat pumps, boilers etc.However, despite all the above caveats and complexity, I will try to pick out certain trends or surprises from the notes I took at the time, with the added assistance of the first report (second one now close to being signed off by Prof John Currie).Firstly, comparing respective updated design SAP predictions to as-built, space heating in isolation varies much more widely than total regulated energy – a median value of +66% cf. +15%, with respective ranges +10% to nearly +700% (plot 11, Stewart Milne Sigma 2) and 2% (Plot 18, Campion Homes Val-u-Therm Passivhaus Standard) to 79% (plot 6, Scotframe Val-U-Therm). We may also note in the passing that the Passivhaus had the lowest total energy per unit area of any divulged to us by Julio – approximately 64 kWh/m2 including all unregulated appliance usage, and less than 15 kWh/m2 more than the SAP estimate for regulated energy, excluding appliances.Secondly, having raised the issue of Julio’s approximations for total monitored energy consumption including all unregulated appliance usage, this gives a mean increase of 78% compared with the as-built

SAP prediction for regulated energy, with percentage increases varying widely from over +230% down to a mere 13%, with the median 70%. When this is expressed as an energy difference per unit of floor area, the mean is about 47 kWh/m2, and median slightly greater at nearly 50%. Again the range varies significantly from as much as 127 kWh/m2 (Lomond Plot 22 with its total energy consumption over 200 kWh/m2) down to as little as 9 kWh/m2 (Future Affordable Plot 20), implying extreme frugality or even absence from home. However, not all of such values can be attributed to consumption by appliances. The highest percentage, although not the highest absolute energy difference, occurred in a dwelling with an air source heat pump (plot 19, > 230% increase at 58 kWh/m2) where in cold weather and depending on hot water consumption by occupants as well as thermostat settings for space heating, electric immersion may well have to provide back-up. Indeed, thermostat settings coupled with ventilation regimes may also be partly responsible for the part of the difference between total energy consumed and the SAP as-built regulated predictions. Although Plot 19 had an MVHR system, if the occupants left doors or windows open for significant periods during the heating season (MVHR irrelevant during such times), energy consumption for space heating would inevitably increase. Thirdly, in terms of energy-related kit, the efficiency of all the

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ventilation units appears to have been lower than the values given by manufacturers – averaging over 9% lower efficiency in eight MVHR systems listed in the first report. The Lomond houses with their passive supply via ‘dynamic wall insulation’ and controlled mechanical extract (CMEV) proved problematic, if not ineffective, particularly the supply perceived as a cool draught. However, it seems that the supply routes were confined to narrow vertical pathways between wall studs, rather than diffused over an entire wall surface and picking up heat as it travelled through a large surface area of insulation. Further, regarding ventilation in all dwellings, we will have to wait for the second report’s appraisal of indoor air quality (IAQ) to find out whether mechanical units have extracted and supplied as expected, and sufficiently to maintain CO2 concentrations within the recommended upper limit of 1,000 ppm, corresponding with a fresh air supply rate of 8 l/s for each occupant. Still on active servicing systems, but turning to solar energy generation, from the information provided, the PV collectors seem to have performed much as expected, including one combined PV-thermal or PV/T panel. However, as noted in the previous paragraph, the air source heat pumps were a concern in terms of performance, and the effectiveness of particular boiler systems is not elaborated in this first report although it was evident that specific systems such as the micro-CHP (Plots 11 & 12) had certain teething issues.

Fourthly, the as-built SAP analysis picked up significant variations upwards in U-values (i.e. greater rates of heat loss than intended), in particular for floors and ceilings. Julio cited issues of construction practice and quality control in this regard. Although as-built SAP predictions take such variations into account, this is inevitably predicated on certain assumptions as to occupants’ use of comfort controls. If higher as-built U-values are coupled with higher settings on thermostats, the implications for the gap between ‘benchmark’ SAP prediction and reality (identifiable via gas meters, where normal boilers are used) become more severe. On the other hand the variations between design baselines for air leakage and measured as-built values were quite modest, with many better than intended. The design intention in the first four plots changed from MVHR (2.18 m3/h.m2) to intermittent extract with acceptable values above the regulatory value of 3.0 m3/h.m2 – varying from 3.07 to 3.59. Of the remaining 23 cases, 18 (78%) were below the design baseline (mean -0.22 m3/h.m2) and 5 (22%) were above (mean +0.84 m3/h.m2). The lowest measured value was for the Passivhaus (Plot 18), where the design baseline was 0.6 and the measured value 0.53 m3/h.m2. Of course, at such low rates of permeability the efficacy of the MVHR system, always paramount, taken together with occupants’ habits with respect to opening windows and doors, becomes very critical for performance. The IAQ analysis in

Julio’s second report will indeed be interesting. Last but not least, despite all the vagaries of predicted versus measured performance, the social surveys had found a high level of satisfaction among the occupants in terms of comfort, convenience and so forth. This is important, and one has to bear in mind that some occupants may need higher than average temperatures for their comfort or may value fresher air quality indoors than the minimum required for health. This is life! Many thanks to Julio for his valuable insights – both during his February 2014 talk, with a very engaged audience, and subsequently by email.As postscript, Peter Barrow of Solar Century, and present at the seminar, gave a very brief presentation regarding the use of PV roofing tiles (Plots 19-21, Block 7). Quoting from the report: “A solar system of 32 x 90Wp Solesia Modern PV tiles was installed on the roof. This system gave an installed capacity of 2.88 kWp, covering an area of 17m2. The expected first year electrical generation for this system was 2,472 kWh. The recorded metered electricity generated for August 2012 was 280 kWh. The total amount of global irradiation on this system over the month of August (17m2) was 1,989 kWh; giving a system efficiency of 14% which is realistic taking into account system and PV module losses.” So that is quite a satisfactory picture, and should at least go some way to offset the increase in consumption relative to the SAP regulated energy prediction for Plot 19!

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the atrium at Banff & Buckie College

He had also invited Cameron Still of Edison Energy to come along so as to be brief us on aspects of the roof-integrated PV panels on the RMJM-designed housing (RMJM, usually pronounced ‘rumjum’ after Sir Robert Mathew and his partner Percy Johnson-Marshall of Royal Festival Hall fame, the only permanent reminder of the 1951 Festival of Britain, which I visited just after my 10th birthday). The show-house terrace, at that time minus kitchens so as to maximise bedrooms for athletes, is to be converted for home ownership, while the swathe of terraces immediately opposite on the other side of an avenue has been designed as rather upmarket social housing, much of it to be taken over by Thenue Housing Association (on whose management committee I served for a good many years). In answer to my query as to whether the FIT income would be divided amongst all householders, Cameron informed that it is hoped that these

registered social landlords (RSLs) will engage with Edison to operate and maintain the solar PV along with its sister organisation AB Services who installed the MVHR units, all this for discussion with City Legacy during the course of the next six months. In other words, there is no cast iron guarantee of direct financial benefit to tenants from FIT; the extent to which FIT might help to alleviate fuel poverty would be up to an individual RSL once a contract with Edison had been agreed. Lets hope for suitable altruism in this regard, especially since the provider is apparently Good Energy.Cameron and Dan explained that the CGC/Edison part of the Village comprised a total of 238 housing units out of 704, 184 of which were in terraces and 54 in two blocks of flats. The Village’s total number of PV panels was 4,479, each with CETC 48 mono-crystalline PV of 250 Wp and a net PV area within the frame of 1.574 m2 – all this totting up to 1,120 kWp and a total net area of PV of 7,050 m2. The intermediate terraced houses typically had 6 panels or 1.5 kWp and larger end-of terrace ones 8 panels or 2 kWp. Cameron told me that although Edison had initially worked on the industry norm of an annual output 800 kWh/kWp, after a more detailed review

ATHLETES’ VILLAGE – BEFORE THE GAMES!This mid-April visit just managed to beat the clock before the terrace of 6 show-houses closed prior to the Commonwealth Games, also implying a flit for our host Dan Donald of Cruden Construction Group (CGC).

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the estimate of total output from CGC’s PV had been revised downwards to 862,277 kWh, or 770 kWh/kWp. Hence, once divided by the 7,050 m2 of net PV collection surface, we arrive at a very creditable estimate of 122.3 kWh/m2 as an alternative annual metric (and for some easier to envisage than the kWh/kWp version). Cameron also provided me with some measured data for the previous month, March 2014, with output at five different addresses varying from 81-108 kWh, somewhat higher that the 70-93 range predicted. Although extrapolation from a single month to a year is not that reliable, I nevertheless calculated that a 6-panel address in Springfield road with 91 kWh output in March (assumption = 1.06 x average month) might translate to some 124 kWh/m2 over a year or 772 kWh/kWp – i.e. believably close to Cameron’s annual estimates above.Another key energy feature of the Village is the CHP system installed by Vital Energi, this installed in a purpose-built energy centre and comprising: one 844 kW CHP gas engine and three back-up 3 MW gas boilers and a 70,000 litre thermal store. This will provide all energy for space and water heating, all homes being heat-metered, while the generated electricity is fed to the grid. Distribution of heat to the 704 dwellings and a new 120-bed Care Home is by a 28 km network of pre-insulated buried pipes. It has also been future-proofed for 750 more homes as part of the Legacy Phase requiring an additional CHP engine, boiler and storage capacity. The homes themselves are expected to reduce carbon emission by 60% compared with the norm, but the inclusion of the CHP is expected to increase this up to 95%. The Nuaire MRX BOX 95 MVHR units are all part of this energy-reducing story; noting that in the show-terrace these are housed in triangular attic voids on the upper floor and readily accessible by means of a wall-hatch for changing filters and any other maintenance. However, my research unit MEARU has found quality

control issues in that many MVHR units neither exhaust at the specified rate nor supply at a rate adequate for supply – for example, two persons in a bedroom overnight require 16 l/s to ensure CO2 does not exceed 1,000 ppm, even though this is not explicitly spelt out in Building Standards. Dan told us that air-tightness varied between 2-3 m3/h.m2 @ 50 Pa; that windows were double-glazed Nordan with argon filling and a low-emissivity coating; that panel wall and roof construction was designed to be 40-50% more efficient than regulation standard; and that a Users’ Manual was being prepared by the

Consortium. The other risks to energy conservation, already mentioned in relation to the Dunfermline Showcase, is that occupants set thermostats overly high and may open windows while heating and MVHR is operating. However, the metering of heat may act as a tangible disincentive in this regard. Watch this space for feedback!

Many thanks to Dan and Cameron for making this viewing possible under relatively tight security conditions already in operation, as well as for the follow-up responses to my various queries.

Gloria Lo poses a question

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Essentially, the building is a minimalist rectangular timber box of 120 m2 (110 also quoted) on a

concrete base, oriented so that the main space has windows along its long side facing some 30 degrees west of south and north of west on its short side. Externally, a rain-screen of cement-based boards have been glued in place so as not to compromise minimalist clean lines. Although our visit was in the morning, arriving 9.30, by the time John was showing us round inside the south-eastern sun was already striking the long west-of-south façade obliquely, and internal solar blinds were down to shield the workstations along this wall (see site plan: http://www.cicstart.org/userfiles/file/IR4_16-20.pdf ).

BRE INNOVATION PARK, RAVENSCRAIG

A rather small group of SSEG members met up on a gloriously sunny, mid-March day at BRE’s Innovation Park at Ravenscraig, the site of Motherwell’s former steelworks. Our guide for the morning, John Reid, greeted us at the BRE Visitor Centre, this completed May 2012 and designed by Kraft Architecture, a collective practice owned and run by Bruce Newlands. There is a useful pdf about the centre produced by the A+DS Sust Programme: www.ads.org.uk/download/8872_bre-visitor-centre-case-study-1.pdf However, I’ll include a few notes here taken at the time.

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John also pointed out that the construction of the ‘structurally insulated panel system’ (SIPS) timber walls and lattice-truss roof (in Scottish timber) concealed steel portals at various points to provide adequate stiffness – these were first to be erected on the base, with the prefabricated timber components then craned in and laced around them. Looking at the completed shell of the building, I wondered if the solid SIPS parts of the short end-walls together with the ‘cross-laminated timber’ (CLT) cross-partition at the east end of the main space could not have provided adequate rigidity – the steel portals seemed like braces put on before the belt! More importantly, in terms of energy efficiency triple-glazed Internorm timber windows have a design U-value of 0.8-0.9 W/m2K; while other key performance indicators or KPIs are: walls 0.15, roof and floor 0.1 W/m2K and air permeability less than 1.0 m3/h.m2 (https://connect.innovateuk.org/web/building-performance-evaluation/bre-visitor-centre ). Heating is by low-temperature floor coils set into the concrete floor and supplied by an air source heat pump (ASHP), presumably augmented if required during very cold weather by the immersion coil in the heat storage cylinder. The floor is finished in a solvent-free product, Masterop by BASF, and is an elastomeric and polyurethane product. Similarly the external roofing membrane is a product called Noxite, which uses sun, wind and rain to transform harmful nitrogen oxides into harmless nitrates. There are also occupancy sensors and daylight sensors to control artificial lighting when daylight is inadequate: “During the design stage, a number of iterative analyses were carried out in order to determine the ‘optimum’ balance between natural light levels and thermal performance.”Another feature required to maintain the visual purity of the formal ‘box’ was that both a 45 kWp PV array and a flat-plate solar-thermal panel were laid at a rather low pitch (perhaps 20º judging from online photo) on the roof so as not to be visible from outside above a parapet of approximately 600 mm. The PV is grid connected with an AC ‘Sunny Boy inverter, but also has DC batteries in an externally accessible store (south-easterly side) to enable stored electricity to be sold to the grid, and has a 10-year lease arrangement rather than being set up for FIT. The ASHP was also roof-mounted and not visible for the first floor of an adjacent house, with the roof trim just above eye-level. (Indeed, judging again from the on-site photo, it looks as if the top of the ASHP is level with the top of the parapet). One of John’s minor grumbles concerned the inclusion of a very small plant cupboard within the main space, this incorporating an Ecodan thermal store (double-coil not fitted), the MVHR above its door, and doubling as a utility store. The Energy Systems Research Unit (ESRU) at the University of Strathclyde is carrying out remote monitoring. This will catch environmental issues such as how effective the solid concrete floor along with CoolZone phase-change material (pcm) ceiling tiles are at damping down swings in temperature. But it is not known if surface temperatures are recorded as

well as air temperatures, and in any case it is unlikely that the effect of this pcm (embedded wax pellets) will be significant relative to the large thermal capacity of the floor, which will be unheated during warm weather. The monitoring is also unable to gauge indoor air quality (IAQ) since the key indicator CO2 is not being recorded; nor I assume will it be able to evaluate the ability of the Fermacell internal wall linings to absorb volatile organic compounds (VOCs) unless air sampling and analysis is undertaken in addition to the remote data gathering.

We then moved on to look at some of the ‘innovation’ dwellings constructed so far, starting with the one for AppleGreen Homes by George Skinner of Space Six Architects. The objective of AppleGreen’s CEO, Alan Wallace, with at least one eye on the Chinese market, was an affordable zero-carbon prototype, area approximately 125 m2. The initial design idea of using modified industrial steel shipping containers was abandoned due to their spiralling cost, but the aesthetic of the realisation at Ravenscraig is almost identical to that initially envisaged (e.g. as published in Project Scotland, May 2011, p 16); the first floor clad in natural larch boards above a smooth white-rendered ground floor. However, ‘the devil is in the detail’ as they say, and the addition of a column to support the considerably less sleek access stair from first floor to roof terrace, with its awkwardly cantilevered landing above the entrance door, is a considerable aesthetic threshold detriment – perhaps rather less jarring from inside looking out. Indeed, it suggests that the architect’s watchful eye may have been sidelined during the building process.

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Also, the final structural and constructional solution, a chunky recycled steel frame with timber infill wall and roof panels and hollow-rib precast concrete first floor to enhance thermal capacity, was a considerable departure from the originally envisaged steel containers. These implied their own problems, given that the steel shell, with its virtually infinite vapour resistance, would have had to have been on the inside of a new insulating jacket; but the steel columns, as built, appear to constitute significant thermal bridges.

Nevertheless, the AppleGreen has many positive attributes: 4 kWp PV collection on the roof, leaving 40% of area for amenity; MVHR ventilation; generous high-performance Nordan windows; NIBE condensing gas boiler serving Myson underfloor heating (manifold allows room-by-room adjustment); water-based Isothene foam insulation; living, dining and kitchen on first floor to keep ground floor bedrooms cooler; and Siemens control from a smart-phone. Overall, despite its aesthetic and constructional rough edges, as well as the limitations of a detached house, the aspiration of an affordable zero-carbon, or even low-carbon, living model remains a sound one.Moving on, John led us across the ecologically-revived and storm-drainage-conscious landscaped territory to a facsimile 1920-30s ‘four-in-a-block’ with each of its flats ‘retrofitted’ to a certain standard, from baseline regulation up to ‘Gold’, and promoting particular active technologies along with various insulation tactics. Without going into too much detail, the key message was that such faux-retrofits highlighted the problems of space relative to kit. For example, small and narrow kitchens struggled to accommodate items such as an electric Thermoflow Combi, some 1,600 mm tall by 550 mm square.

Finally, John showed us round the ‘Resource-efficient House’. Its stated aspirations, slightly edited, are as follows: “the design build and deconstruction of a family home which makes best use of materials, water and energy during its life-cycle; manufactured off-site in a controlled factory environment as four ‘pods’; a net zero-carbon building which meets 2016 Building Standards at the highest level; modern construction methods, eco-friendly products and innovative green technologies [enable] a repeatable construction model that is both economical to build and affordable to live in; [and] also makes it easy to maintain a green and healthy lifestyle.” An example of the last aim that I particularly enjoyed, having spent several years investigating the environmental impacts of domestic laundering, was the roof-glazed loggia at first floor level with its retractable clothes-drying lines. Another aspect noted was that both the semi-transparent 800 Wp

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PV covering this loggia and the main array on the roof of 2.25 kWp (nine 250 Wp panels) fed electricity into batteries or directly into oil-filled radiators, rather than the grid. Yet another was the air-source heat pump serving domestic hot water, located on top of the cylinder and sourcing its air from the attic, the Vortice MVHR exhaust and the outside, not to mention a wood-chip stove/boiler located in the main double-height living space, which is capable of heating the hot water although not needed due to the heat pump, etc. There were also many useful information posters for visitors; although a small niggle is that sometimes the information was at odds with that given by our eminently informative guide, John. For example, one states that the main PV array heats hot water, which, given the heat pump and the woodchip stove, was clearly not a priority; and that the “next generation” thin-film PV over the loggia is 90 Wp, not 800 Wp (perhaps nine panels of 90 Wp?). It was also John that gave us the useful information that in this project cold-bridging by its steel frame had been avoided by use of a relatively thin layer of aerogel. Many thanks go to John for such a comprehensive, informative and enjoyable tour – ‘good job’ (as they say in USA … at least in Washington State). As a goodbye to Motherwell unconnected with BRE’s Innovation Park, I’m including a photo of the Ravenscraig Regional Sports Facility, designed by Populous of 2012 Olympic Stadium fame, opened October 2010 and used as a training facility for Glasgow’s Commonwealth Games this year. Although the nickname ‘Armadillo’ was coined many years ago for Norman Foster’s auditorium at the SECC in Glasgow, this building not only evokes that metaphor, but also provides natural daylight via roof-windows at each section of the shell.

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There were at the end of the day seven very creditable nominations submitted. Taken

alphabetically according to the first letter of the project (as listed by the organisers, rather than as submitted) these were: 1) Edenhope: Sarah Eno & Andy Swales; 2) Gruinard; 3) John Gilbert; 4) Neil Burford, University of Dundee School of Architecture; 5) Regeneration of Banff & Buchan College by CDA Architects; 6) Sporsnis Ness Community Facility; 7) Sunamp Ltd in association with AES Solar Ltd. The judging held on 31st October 2013 required nominations in each award category to be initially whittled down to no more than four. I was one of the judges, as were others with knowledge of each category, and although of course when it came to SSEG’s Award category I formally expressed my interest, I had to be available to answer any queries from the rest of the panel – i.e. technical or matters of clarification. On this basis, numbers 4, 5 and 7 fell by the wayside. Reasons given for similar rejections in other categories were lack of performance evidence or

THE SCOTTISH GREEN ENERGY AWARDSThe planning of SSEG’s first involvement in this annual event was noted in the previous SunTimes, this involvement centring round the inclusion of a new category, ‘The Kerr MacGregor Memorial Award for Innovation in Solar Energy’.

excellence, and/or work in a relatively early development stage, and it should be noted that in our category Kerr’s particular passion for solar thermal applications had been stressed. Finally, and I believe it was a close-run matter, John Gilbert’s East Whins housing at Findhorn deservedly won the day – the only built project to be based solely on solar thermal capture, both active and passive. Apart from Gruinard, submitted by Judith McDermid (Suntimes 31, pp 12-13), all other except Neil Burford’s and Sunamp/AES’s were either described in the last issue of Suntimes (32) or are included in this issue. Neil’s nomination was for a student-led research project, ‘Macro Micro’, a small demonstration building supported by Nordan, a studio that has been described as ‘the UK’s first “self-build, energy autonomous Passivhaus”, a fully automated off grid, live/work timber studio, some 50 m2 in the Botanic Gardens Dundee’ (Nordan promotional literature). The description submitted for the Green Energy Award also stated: “A self-build, it is being delivered by a multi-disciplinary team from across the University and in collaboration with the Wood Studio at Edinburgh Napier University’s Forest Products Research Institute.” It is also hoped that a visit to this venture may be arranged as part of the 2014-15 SSEG programme. The Sunamp/AES nomination was for a new and “very compact form of thermal store, the Heat Battery, that uses Phase Change Material (PCM)”, which has been modelled for domestic hot water (DHW), indicating a significantly improved solar fraction up to, or more than, 75%; and an enlarged panel area is envisaged “in order to encompass Solar Thermal Central Heating” with further testing at AES’s factory as the next step. Again, watch this space for future SSEG visits.The Awards dinner was held in the main atrium at the National Museum of Scotland in Edinburgh, designed and engineered originally by Francis Fowke (1823-1865) and now as refurbished by Gareth Hoskins Architects in 2011. Hosted by BBC’s inimitable Fred MacCaulay, it was a grand evening and, despite deep snowdrifts across Scotland preventing attendance by our George Goudsmit and Elaine Morrison, it was much enjoyed by the rest of the SSEG attendees, including our three guests from Kerr’s family including his widow Anabel. It’s just a shame Kerr could not have joined in.

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For a start, the eight German Evergreen 190 Wp PV panels, carefully lined up with the central sunspace,

with four more intended as shading canopies to windows, have now expanded to eighteen panels, still at 190 Wp each, but configured differently and bringing the total up to 3.42 kWp. The array is now estimated to generate some 645 kWh/kWp or 95 kWh/m2 net PV collection surface (23.346 m2). This is somewhat lower than others quoted in this issue, but one must bear in mind the relatively rainy location in the hilly Borders, as well as the relatively old collectors. Also it is no longer completely off-grid, although the batteries remain as part of the system. These are again carefully integrated with the slated roof and glazing on the remainder of the south-facing surface, the panels themselves mounted on ‘Onduline’ corrugated sheeting to allow air movement and hence

RETURN VISIT TO ‘EDENHOPE’Time just keeps flying – the

last occasion before April

2014 when SSEG visited

‘Edenhope’, the much loved

home of Andy Swales and

Sarah Eno, was the early

summer of 2008 (SunTimes

27, pp 21-23). Those who

keep hard copies of back

numbers can therefore check

out differences.

cooling behind the PV, this in turn fixed on to the timber sarking. The 3 m2 solar thermal, unglazed, but insulated with 100 mm Kingspan, Scandinavian Sunstrip absorber inside the sunspace has also been reconfigured. This is a direct system with a 5 W pump, since frost protection is not required. Its tilt is also now less vertical than formerly and seals off the previous gap between the main ground floor living/dining space and the first floor sun-kissed sitting alcove between the two bedrooms.

At this point I am tempted to include Andy and Sarah’s submission for the Scottish Green Energy Award 2013 (see earlier article); but note that this was based on ten fewer PV panels totalling 1.52 kWp, as was the case at that time last year...

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KEY ACHIEVEMENTS TO DATECompletion of near-autonomous rural dwelling, with passive and active (PV and flat-plate) solar features: The prime objective, which has been successfully realised, was a house that cost relatively little to build, little to live in and was consistent with key environmental aspirations. The solution revolves around the practical application of solar design in an essentially commoditised build. The design process was based on deciding on an energy model, energy seen as the main cost in use, and finding the most cost effective way of realising it. The result embodies 'simpler, cheaper' ideas in a spacious house with, effectively, all energy costs in construction and occupation covered or offset by solar – passive, active solar thermal (innovatively internally mounted) and photovoltaic (PV). The design was strongly constrained by this solar strategy based on energy modelling. The house has a 'hybrid' electricity supply. Technically it is off-grid, but the battery is charged by off-peak renewable grid power. All the PV generation normally goes to the grid but there is provision to use it for battery charging if, as they say, 'the lights go out' for a protracted period.

Output from active solar systems relative to demand: There are eight roof-integrated Evergreen ES 190-RL mono-crystalline PV panels, net collection area 10.37 m2 (8 x 1.297 m2) at 35º tilt (from horizontal), facing due south with negligible shading and rated at 1.52 kWp. Based on metered output from 9th June 2011 to 21st October 2013, the average annual output has been 980 kWh.

This translates to 645 kWh/kWp or 94.5 kWh/m2. A hot water immersion heater, installed July 2013, should receive some 750 kWh/year from the PV. The thermal store is highly insulated and provides 'instantaneous' hot water and heat for a towel rail, small radiator (one) and kick-space heater to cost-effectively 'top-up' the house during its 3-month heating season. A solar thermal ‘Sunstrip’ absorber, 3.2 x 1.05 m (3.36 m2) set at 35º from vertical is estimated to provide 1,400 kWh/year (417 kWh/m2). The total electricity demand, based on metered consumption from 12th May 2011 to 21st October 2013, is approximately 1,800 kWh/year or an extremely modest figure of 10.7 kWh/m2, based on a floor area of 168 m2 with a ceiling height of 1.6 m or more. Most of this is initially required to charge batteries.

Passive/active performance, mechanical ventilation heat recovery (MVHR): The shell has good but not excessive insulation (U-value <0.1 W/m2K) with good quality low-e double-glazing (triple not cost effective) and good air-tightness in a direct passive solar design; with thermal mass provided by clay plaster (maintains temperature at night). The solar thermal performance is such that it warms up even on overcast days (solar gain exceeds heat loss). MVHR by a Danish Itho air-to air unit, supplies main spaces via 125 mm ducting, and is coupled to a sub-soil heat exchanger (passive technology). This allows the house to be ventilated with air pre-warmed in winter and pre-cooled in summer while operating without heat recovery. The solar thermal panel under a section of glazed roof provides hot water without added weatherproofing (2/3 of

the cost of a conventional roof mounted unit) or frost-protection equipment. Located in a warm space, it gives good year-round performance as indicated above. It directly feeds a thermal store along with a back-boiler in a small stove and immersion heaters powered by photovoltaic generation or cheap off-peak renewable grid electricity.

SUPPLEMENTARY INFORMATIONThis house is an important rural paradigm fo r Scot land, f i r s t v i s i t ed under construction by SSEG in 2008, and nominated by longstanding member Paul Simpson “for innovations in creating a self built autonomous house … without the benefit of any formal education in engineering, architecture or building … driven by an ecologically responsible attitude towards the planet.” It conforms to a sustainable approach with a simple basic form and construction providing a passive solar, low-energy base from which active solar systems play a vital auxiliary part (not ‘eco-bling’, but essential ‘kit’ alongside other mechanical aids). Roof-integrated PV has a lower installation cost than retrofit, with panels, sourced from Germany, manufactured using a fairly low-energy process and shipped by surface so their carbon cost is reduced. The array is currently being expanded up to eighteen panels to give 3.42 kWp, and assuming the same performance indicated above, the yield should be over 2,200 kWh/year. Rainwater collection and treatment saves about 80% of the energy cost of water. By using commoditised materials and building techniques the spacious 3-bed house cost under £150k.

... I think the only rather important matter that I would add to the above carefully word-rationed submission is that concerning the pond in front of the sunspace. Fed via stainless steel gutters and down-pipes from the roof, Andy explained that this constituted a buffer between the collection of storm water and ‘Edenhope’s main water storage and filtration system in the undercroft, an un-floored space below the house with a Fermacell soffit fixed to the floor joists. This utility space houses 25,000 litres capacity in a large corrugated metal tank (very comfortably sized from 30 years of rainfall data, and avoiding the need for composting loos); and from here some water is pumped up to a smaller tank further up the hill – roughly level with the roof ridge to provide a gravity supply. The undercroft also houses the ‘slow sand filter’, which is essentially a big barrel full of sand to filter water for drinking. It only needs to be cartridge-filtered thereafter in order to remove humus and a UV steriliser that was seldom used as Andy and Sarah mainly drink coffee or tea. These last two are both located in a service zone within the back lobby.Andy did add a few more technical details such as the two batteries of 12 cells running at 12 volts and

their 3 kW inverter; and the fact that he can economically buy back electricity at night in order to charge his batteries; also that he sells to the grid on a ROCS basis, not FIT at 9 p/kWh although there still seemed to be a smaller deemed FIT component (if I got all that right). His Vrogum Danish double-glazed, low-emissivity windows are made of an oak-like wood and are estimated to have a U-value of 1.2 W/m2K. On the heating and plumbing side, Andy also added that the heavily insulated 210 litre Gledhill thermal store was served by a small log-stove as well as the solar thermal panel, with an ‘ImmerSUN’ immersion coil at both bottom and middle (nighttime), and that in addition to hot water this served an 800 W spiral towel rail in the bathroom, as well as a small radiator in the upstairs sitting alcove and, for heat boosts, a 1.2 kW ‘wet’ fan convector below the sink.Talking about the kitchen, Sarah then served up a very welcome and scrumptious lunch. Thank you both so much for your weekend time and hospitality, and it was simply great to see you, Andy, up and about again, and looking remarkably spry.

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Public interest focussed more than ever onto PV. However, we managed to share interested parties

between the SSEG stand and the stand holder opposite us who deals mainly with PV, Cairngorm Energy. Interest in solar thermal was more realistic though than previous years. The projects that people were working on were on the drawing boards and the decision to go for solar thermal had been made. We were able to assist with advising on the best system designs etc.Several people were interested in becoming SSEG members although the actual figures are difficult to assess as not everybody that subscribes informs us of how they got to know SSEG. The show was less solar oriented than previous years. Even the PV manufacturers were less represented. It may be because of the FIT coming down and RHI slowly gaining momentum.

ALL-ENERGY EXHIBITION & CONFERENCE 2014BY GEORGE GOUDSMITSSEG were again generously offered a free stand at this prestigious annual event. The 2-day show was attended by a variety of interested parties, not in the least academically orientated people. Several SSEG members ‘personned’ the stand so that most aspects of solar were covered. ALL-ENERGY 2015 will be held in Glasgow.

A greater number of participants are

expected because it is closer to a larger

number of people. All-Energy has again

offered SSEG a stand in exchange for us

promoting the show. This is a most

enjoyable and pleasant partnership

arrangement and SSEG are planning to

make the most of it. Solar applications

may be small fry in a very big energy fish

pond but its potential is greater than

generally acknowledged and it is

renewable energy without the NIMBY

opposition of wind farms.

AES flat plate thermal solar collectors relate to roof windows in John Gilbert's award-winner (p18)

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Suffice to say here that I co-authored a paper with Janice Foster of MEARU, who gave a talk at this

year’s SSEG AGM (also to be included in SunTimes 34), and that certain aspects of this relate to earlier items in this issue – in particular the various metrics used to

EUROSUN 2014 AIX-LES-BAINS, FRANCE

A longer piece about this event, including its

technical tour will be included in SunTimes 34,

2015. There may also be a feed-back meeting in the

2014-2015 SSEG programme.

Notes: m2 PV = Net surface area o f photovol ta ic ce l l s wi th in enclosing frame; Reference yield* denotes irradiance figures derived using PV Geographical Information System (PVGIS), 2001-12; PR = Performance Ratio (of previous two columns – dimensionless)

The data given in SunTimes 32 indicated monitoring periods for each of the four locations varied; Sporsnis, the longest from January 2008-2012, annual average 9,109 kWh. That for Banff & Buchan College has been estimated from an 18-month total from March

2011 to September 2012 (using a factor of 0.622 based on theoretical monthly incident irradiation). The resultant 12-month f igure of 1 6 , 8 7 7 k W h i s c o n s i d e r e d reasonably robust; and of its two figures given for capacity, 20.20 kWp is the value provided by the installers (101 racks @ 200 Wp per rack of 40 tubes 1.0 m long); and 18.38 kWp is a published laboratory measured value of 182 Wp for a single rack. The Survey Solutions HQ uses measured data from 31st July, 2012, to 5th August 2013, adjusted to 365 days to give a total of 35,557 kWh; and that for the

Muir Group HQ is for a single year measured from 13th July 2011, 70,500 kWh.

Without going into any further detail, one may simply note that respective ranking in columns three to seven vary significantly. Although annual kWh/kWp values are routinely quoted, the data demonstrate that they can be deceptive relative to metrics based on PV area; Sporsnis at the highest latitude coming first in its annual yield per unit area as well as its Performance Ratio. But it does have long summer days, and the marine

measure the performance of PV. Four case studies are compared, all mentioned either in this issue or the previous one, and I have summarised key data in a single table here, with some explanation of nuances (without infringing copyright on the paper itself):

PROJECT & PV TYPE/MAKE LATITUDE (ºN) CAPACITY (kWp/m2)

Sporsnis, Ness, Lewis: 58.5 10.20/72.4=0.1409

BP Solar BP5170S

Banff & Buchan College, Fraserburgh: 57.7 20.2/189.6=0.1065

Solyndra 18.38/189.6=0.0969

Survey Solutions HQ: 55.9 48.0/299.0=0.1605

Jetion JT250 SBb Mono-crystalline

Weir Group HQ: 56.0 100.0/646.8=0.1546

Hyundai Mono-crystalline type 1

SUMMARY OF PV PERFORMANCE DATA FOR FOUR CASE STUDIES

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location will boost albedo to an often diffusely radiating sky vault. C o n t r i b u t i o n s i n t e r m s o f percentage of demand also vary significantly, with the Weir Group HQ reported to be doing quite well at some 16%, and Survey Solutions allegedly considerably better, although no electrical consumption figures were available. That for B a n f f & B u c h a n w o u l d b e insignificant relative to the entire complex, but significant relative to the new atrium; and that for Sporsnis is unknown, but likely to be significant if considered together with its wind-generated electricity.

ANNUAL YIELD ANNUAL YIELD REFERENCE YIELD PR (kWh/m2 PV) (kWh/kWp) (kWh/kWp)*

126 893 968 0.92

90 836 1,160 0.72

918 1,160 0.79

119 741 1,440 0.51

109 705 993 0.71

Solyndra

Jetion

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Sun-Spots

Note: all articles in this issue unless stated otherwise are by Colin Porteous, and represent his views rather than those of SSEG as a whole. If members wish to respond, this would be most welcome.

Colin may be contacted at the Mackintosh Environmental Architecture Research Unit (MEARU), Mackintosh School of Architecture, Glasgow School of Art, 167 Renfrew St., Glasgow G3 6RQ. Tel/fax: 0141-353 4740. e-mail: c.porteous@gsa.ac.uk

Thanks to Craig Laurie at the 'Mac' for printing. Design and layout by Mary Patrick Cusp Design: mary@cuspdesign.co.uk

IT'S GOOD TO TALK... AND OBSERVE

SSEG AGM 2014This year we were back in Glasgow at Glasgow Caledonian University. The Committee for 2013-14 bears remarkable similarity to last year as follows: Chairperson, Anne-Marie Fuller (back from her maternity leave thus relieving Colin from his Acting Chairperson role, and representing us until at least April 2015 when there is planned move back to Ireland); Treasurer, Stas Burek; Secretary, Rosalie Menon; Membership Secretary, Fiona MacLennan; other Committee members, Elaine Morrison, George Goudsmit, Jim Norris, John Gilbert, Rory O’Riordan and Colin Porteous; plus one new ex-officio member Peter Randall. Their affiliations are as follows:

Anne-Marie Fuller: Technology Business Development Executive covering the Solar theme for the Energy Technology Partnership (ETP) and the Scottish Institute for Solar Energy Research (SISER); Board member of Solar Cities Scotland.

Dr Stas Burek: Senior Lecturer, School of Engineering and the Built Environment, Glasgow Caledonian University.

Rosalie Menon: Lecturer in Architectural Technology, Mackintosh School of Architecture; Co-director of MEARU, Mackintosh Environmental Architecture Research Unit.

Fiona MacLennan: Buildings Energy Consultant.

Elaine Morrison: Managing Director of Empower Renewables Ltd; Research Associate with the Centre for Remote and Rural Studies, University of the Highlands and Islands.

George Goudsmit: Managing Director of AES Ltd and Member of Thermal Working group of Solar Trade Association; Co-founder of Scottish Renewable Forum (SRF).

Jim Norris: Director of Solar Energy Systems, Dunfermline.

John Gilbert: Director of John Gilbert Architects Ltd; Chair of RIAS Scottish Community Projects Fund.

Rory O’Riordan: P/T Lecturer in Building Services Engineering (MCIBSE CEng), Edinburgh College Granton; Board member (and Founder) of Dundee Sun City, now expanded into Solar Cities Scotland (New Projects).

Colin Porteous: Professor of Architectural Science, Mackintosh School of Architecture and Co-director of MEARU, Mackintosh Environmental Architecture Research Unit; Board member ISES-Europe.

Peter Randall: Managing Director, Solar Kingdom Ltd.

SSEG PROGRAMME FOR 2014-15Following upon Janice Foster’s intriguing narrative of the solar refurbishment at Edinburgh’s Commonwealth Pool, it is hoped that a site visit from a limited number of members can be arranged (roof access being awkward for more than a few folk). We also hope that Janice will be prepared to give us feedback from Eurosun 2014 in France, including its technical tour and any recent innovations. The Macro Micro studio project by the School of Architecture at Dundee University is also now at an advanced stage and their Dr Neil Burford has agreed in principle to hosting a visit. We may also include a visit to Neilston Development Trust HQ in a converted bank (with pellet boiler and solar thermal), also with a 28% share in its Community Wind Fram, Project Co-ordinator Pauline Gallagher. These and other events and visits will be fleshed out in less than a week’s time (as I write this). Having missed our Wiston Masterclass in 2014 (no mutually suitable dates could be found), we now have a weekend booked, 13-15th March 2015, where we hope to tackle the self-build of a meditation/poetry hut.

NEWSQueens Cross Housing Association, longstanding promoters of solar energy, are initiating Scotland’s first ‘Ecopod’ project, a low-carbon heating solution by Carillion; upgrading 542 deck-access homes in Woodside and 448 flats in four towers at Westercommon, the latter supported by ground source heat pumps.

MEDIAThe magazine of CAT in Wales, Clean Slate No. 93, Autumn 2014, celebrates CAT’s 40th birthday, with a note of its architectural students’ re-visioning ideas for the centre and many other articles of interest – some warnings, such as the many downsides of underground coal gasification, some optimistic, such as ‘Tidal Power in Zero-Carbon Britain’ by our able guide during our last visit, Toby Kelner. And in Scotland, where the RHI will hopefully have a positive impact, the Scottish Governments’ report ‘Towards Decarbonising Heat: Maximising the Opportunities for Scotland’ deserves perusal, recalling Kerr MacGregor’s long campaign in this regard. As noted in previous issues of SunTimes it should be still possible to get a copy of ‘Solar Architecture in Cool Climates’ by Colin Porteous with Kerr MacGregor, Earthscan, 2005, at a reasonable price from Amazon or Abe Books – nine years old but still very relevant.