Carbon counting roaf

Towards a Standard for Carbon Accounting: a

view from CIBSE

Hywel DaviesCIBSE Technical Director

and Stuart Macpherson Irons Foulner Consulting Engineers

Current Standards Activity

BSI, CEN and ISO are working on standards related to carbon emissions from buildings and their component materials and systems

• BS PAS 2050 – measurement of embodied greenhouse gases in products and services

• CEN - Sustainability of construction works

• CEN – Strategic energy management forum

• ISO – sustainable construction standards

Carbon counting standards

• 4 strands of standardisation (at least)

• ISO well advanced on a general framework for environmental impact measures

• CEN developing standards in response to a mandate – possible standstill on national efforts

• BSI developing the PAS on carbon

PAS 2050• Being developed jointly by Carbon Trust,

Defra and BSI• Aims to “develop an agreed method for

measuring embodied GHG emissions which can be applied across a wide range of product and service categories …to enable companies to measure the GHG related impacts of their products and reduce them.”

• Carbon and GHG specific

Directives

• The EPBD

• Scottish Building Standards

• Energy Assessors in Scotland

Carbon Accounting?

Its not just about counting carbon, but controlling it

Thank you for listening – Any questions?

What are we really trying to standardise?

• Carbon impacts or Environmental impacts?

• Products? Systems? Whole buildings?

• Cradle to gate, or cradle to grave?

• Life cycle? When does life begin and end?

• Impact of a building? Of what goes on in it? Of how people get to it (to work on it or in it)

Comparing corporate performance on climate change – what metrics?Dr. Craig MackenzieDirector, Carbon Benchmarking Project

University of Edinburgh Business School

The scope for low cost reductions

Source: Vattenfal

Breakdown of the Tesco footprint

Add note on fridge energy?

Refrigeration

Tesco CSR Report 2007

Direct CO2e emissions

Total UK Carbon Emissions

0

500,000

1,000,000

1,500,000

2,000,000

2,500,000

Somerfield Cooperative Waitrose Marks &Spencer

Sainsburys Morrisons Asda Tesco

Ton

nes

CO

2e

No Data

Relative carbon intensity?

Carbon intensity (tonnes CO2e/£turnover)

0

20

40

60

80

100

120

Somerfield Sainsburys Marks &Spencer

Tesco Cooperative Waitrose Asda Morrisons

CO

2e/£

turn

over

NB: this slide does not give an accurate comparison of performance

No Data

Meaningful comparison?

Carbon intensity (CO2e/£tunover)

0

20

40

60

80

100

120

Somerfield Sainsburys Marks &Spencer

Tesco Cooperative Waitrose Asda Morrisons

CO

2e/£

turn

over

NB: this slide does not give an accurate comparison of performance

Food processing

business

Foodnon-food

split

Food-non-food

split

Foodnon-food

split

Use of biodiesel

Green tariffelectricity

Green tariffelectricity

Data estimated

Data incomplete

No Data

Add note on fridge energy?

Refrigeration

Tesco CSR Report 2007

An alternative strategy

% f-gas leakage pa

KWh/linear meterof refrigeration

Diesel litres/pallet delivered

Average store energy rating

% electricity from renewables weighted for additionality

Wider implications

Benchmarking needs:• Better data quality• Sharper standards• Segmental carbon reporting• Identification and reporting on normalisation factors• Avoiding carbon reductionism• Activity-specific metrics• Activity/sector-specific reporting standards

• Collaborative sector/activity projects to define the above

Westminster carbon counting conference, ICE, 24 January 2008

JOINING THINGS UP FOR BUILDINGS

Bill Bordass

the Usable Buildings Trustwww.usablebuildings.co.uk

We need to save real carbon, not virtual

carbon

The Credibility Gapfor a green building award winner

Saving energy and CO2 in a

hurry, using the multiplier effect Reduced demands standards, passive measuresx 0.5? 50 %Increased efficiency better technology, lower resistancesx 0.5? 25 %Waste avoidance better control, management, behaviour?Less 20%? (it could easily be more) 20 %Low-carbon energy supplies on and off-siteHalve the carbon content of the supplies? 10%

To get rapid and cost-effective change,we must press ALL the buttons

NOT, for example relying on a business-as-usual fix with renewables: they won’t work alone!

Use renewable supplies

AND make buildings efficient in use

Making Performance Visible

with building energy certificates

Ambitions of Europrosperresearch project 2000-04:

Display energy certs based on actual energy use. Achieved

• Transparency between expectations and outcomes.Incomplete

• Multiple performance indicators Incomplete

• We now need voluntary supporting measures

Passing on carbon + energy

BPF Landlord’s statement• Improves transparency

• Includes multiple performance indicators• Allows individual tenants to add the energy they

purchase directly and prepare Display Energy Certificates on same basis as whole buildings.

• Avoids double handling if it allows the transfer of carbon from landlord to tenant for the purpose of the Carbon Reduction Commitment.

• Interest being shown by other sectors (business centres, retail, industrial

Passing on carbon + energy BPF Landlord’s

statement

Drilling down furtherto assign realistic priorities

Drilling down even further:

actual versus predicted for lighting

Carbon Counting for Neighbourhoods and Cities

Dr Rajat GuptaDepartment of Architecture

rgupta@brookes.ac.uk

Westminster Carbon Counting Conference

24 January 2008, London

Core methodologies used in DECoRuMMethodology used Details of methodology Outputs

Building Research Establishment Domestic Energy Model (BREDEM) –12

Industry standard to calculate energy use for different dwelling types in UK. Estimates annual energy requirement for space heating, water heating, lights & appliances and cooking Requires 95 input parameters

Annual energy use (GJ/year) Annual CO2 emissions (kg/year) Running costs (£s/year)

Standard Assessment Procedure (SAP) 2001

Government’s recommended system for home energy rating based on energy costs for space and water heating.

SAP rating (scale of 1-120) Carbon Index (scale of 1-10)

Net annual cost method Used by BRE to asses cost-

effectiveness of energy efficiency measures.

Net annual cost/tonne of CO2 saved

Underlying physically-

based energy models:

BREDEM –12 linked to SAP 2001.

Cost-benefit analysis approach

Outputs from DECoRuM Outputs Expressed as

Total annual energy use kWh/year kWh/m2/year

Energy use

Annual energy use by end use kWh/year

Total annual CO2 emissions kgCO2/year kgCO2/m2/year

CO2 emissions

Annual CO2 emissions by end use kgCO2/year

Total annual running (fuel) costs £/year Fuel costs Annual running (fuel) costs by end use £/year

SAP rating Scale of 1 to 120 Energy rating Carbon Index Scale of 1 to 10

Framework for baseline predictionsDECoRuM baseline energy model estimates energy consumption and CO2 emissions of individual dwellings as the basic component for calculation, and then aggregates these to an urban scale.

Dwelling 1

Dwelling 2

Dwelling 3

Dwelling 4

Dwelling 5

Dwelling 6

Dwelling 7

Dwelling 8

Dwelling 9

Street 3

Street 2

Street 1

District 1

District 2

Oxford case study: DECoRuM baseline energy & CO2 model

© Rajat Gupta, Oxford Brookes University, Oxford, UK.

In conclusion

Top down approaches

Are they complementary to each other?

What do we need to adopt for cities to be able to estimate baseline emissions, predict

potential emission reductions, and take action?

Bottom-up models

Highest energy users on the planet

10

20

30

40

50

2000 2010 2020 2030 2040 20501990

Car

bo

n d

ioxi

de

emis

sio

ns

(MtC

O2)

Draft London Plan targets

15%20%

25% 30%

60%

Today(+0.7° C already)

Stern indicates the London Plan targets will not be sufficient

60%

90%

New evidence?

2025

London:Where emissions come from:

21%

7%

Emissions from London

Domestic

Commercial (inc. public sector)

Industrial

Ground-basedTransport

7%

22%

38%

33%

0

10

20

30

40

50

2006 2025

Responsibility for Delivering30% CO2 Cuts by 2025

Source: LECI; GLA analysis

•GLA family (~10%) City

•Boroughs (~10%)

•National government (~30%)

•Private sector (~40%)•Target reduction (30% vs. 1990)

•Mil

lion

tonn

es o

f C

O2 p

er

annu

m

•Business as usual scenario

•Individuals (~10%)

Solar Cities: 2nd International Conference 2006

LOW CARBON WOLVERCOTE

Principles of carbon counting for buildings in use

THE KEY STEPS

The five key steps in counting the impact on the outside world are:

1 Define the boundary of the premises. Boundaries should be where they make practical sense in terms of where the energy can be counted (e.g. the area fed by the meters) and how the area is run (a tenancy, a building, a site; or even a district or a city). One may look at more than one boundary, e.g. for a university the campus, specific buildings, and individual departments; and for a rented building the whole building, and each tenancy.

2 Measure the flows of each energy supply across the defined boundary. Normally this will be annual totals by fuel, though details of load profiles could sometimes be included.

3 Define carbon dioxide factors for each energy supply, as discussed below

4 Multiply each energy flow by the appropriate carbon dioxide factor, to get the emissions associated with each fuel

5 Add them up. to get the annual total of CO2 emissions.

DIRECT EMISSIONS 34%

HOUSE ENERGY 19.5%

TRANSPORT ENERGY 14.5%

INDIRECT PRO RATA EMISSONS 51%

INDIRECT INFRASTRUCTURAL EMISSONS 15%

Carbon Dioxide Emissions will include: (Source:Robert Cohen)Probably the most ‘correct’ approach is to split the scores into four categories:- Direct and measurable- Indirect, pro-rated on the bases of purchases- Indirect, not pro-rated and attributed to the industrial sectors- Fixed infrastructure, not pro-rated and attributable to government policy.

Peter Harper, Centre for Alternative technology

Making Business Sense of Climate Change

www.thecarbontrust.co.uk

DECARBONISING BUILDINGSCASE STUDY: The Sports Hall

The proposed sports halls is: - 36 x 40mx 7m high, - floor area of around 1440m2.- The currently preferred design includes:- 15 Sprung Sports Floor - Lighting should be Multi-Corso set between the badminton courts- Heating system is a Continuous Black Tube radiant heating system.- 160m2 sports storage equipment- Full height glazed screen between corridor and sports hall- Range of fixed equipment including basket ball goals, netball & badminton posts- Side walls to be green or blue to meet badminton requirements-Top 3m of the 3 external walls are designed to include Kalwall Transluscent- cladding, an insulating, diffuse, light transmitting system that eliminates glare hot spots and shadows.

Recommendations:

• High the thermal efficiency of the structure of the sports hall through the use of good levels of insulation in north, south and east walls, elimination of air-infiltration through the building envelope and robust construction.

• Optimised use of natural lighting in the sports hall so reducing the need for high levels of artificial lighting.

• Naturally ventilated sports hall, eliminating the need for mechanical cooling and provision of fresh air.

• Replacement of the proposed high level, high temperature, gas fired, air blown heating system with an under-floor, low temperature heating system powered at least in part by a ground source heat pump system and a wind turbine situated in the school grounds.

• Install a roof mounted solar hot water system to provide part of the high temperature water supply needed for the changing room facilities.

The what works palette of RENs

Source: njsolar

Wind – It works and is available on site

House height 8m

400W turbineElectricity provision: 20% of a householdHeight: 2mCost: £1500-2000

6kW turbine

Electricity provision: 3.5 houses or 20% of a primary school

Height: 9m

Cost: £15-18k

220kW turbine

Electricity provision: 85 houses or 5 primary schools

Height: 36m

Cost: £550-700k

1.5MW turbine

Electricity provision: 1200 houses or 75 primary schools

Height: 65m

Cost: £1-1.5 million

RENEWABLE ENERGY GRANTS:The Low Carbon Buildings Programme

- Stream 2B. (

www.lowcarbonbuildings.org.uk/ ).

• Solar photovoltaics 50%

• Biomass 35%

• Ground source heat pumps 35%

• Wind turbines 30%

• Solar thermal 30%

CALCULATING THE COST BENEFITS OF THE SAVINGS:

Recommendation 3: Naturally ventilate the sports hall and eliminate the need for mechanical cooling and provision of fresh air. Removal of central ventilation plant and fans.

Electricity cost savings 34 kWh/m2/a saved by removal of mechanical ventilation system. = 1440 x 34 = 48960 kWh/a

CO2 savings 21.053 tonnes annumcost savings 1440 x 34 x 5.5 = £2693 annumCost of measure removes c. -£15,000 from plant cost and adds the same for

the opening Kalwal windows at the upper level. Payback 0 years

Recommendation 4: Under floor heating with GSHP power in part with a wind turbine

Replace all air blown sports hall heating system with under-floor heating from a ground source heat pump with wind turbine giving zero energy heating for the hall.

Heating gas saved 307 kWh/m2/a = 1440 x 307 = 442080 kWh/aCO2 savings 83.995 tonnes annumcost savings 442080 x 2.7 = £11,936 annumCost of measure £100,000Payback 8.38years

Key recomendations:

Recommendations and Key Actions

Estimated Annual Savings

Estimated Cost of

Measure

Payback perio

d

Financial Savin

gs

CO2 Savin

gs Energy Savings (years)

£ tonnes kWh £  

high thermal efficiency of sports hall 1,400 9.9 51,840 5,000 3.57

Optimisation of the natural day lighting of the hall 3,564 12.3 64,800 2,000 0.56

Natural ventilation of the sports hall 2,693 21 48,960 0 -

Under floor heating with GSHP and wind turbine 11,936 84 442,080 100,000 3.58

Solar hot water systems 985 6.9 36,500 35,000 35.53

TOTAL 20,578 134 644,180 142,000  

Sue Roaf Professor of Architectural Engineering

Heriot Watt UniversityEdinburgh

s.roaf@btinternet.com