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Test of a High Concentrating PhotoVoltaic System in Denmark - A part of SOL 2000A

Test of a High Concentrating PhotoVoltaic System in Denmark · The Cells ... The purpose of the Test of a High Concentrating PhotoVoltaic System in Denmark ... Test of a High Concentrating

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Page 1: Test of a High Concentrating PhotoVoltaic System in Denmark · The Cells ... The purpose of the Test of a High Concentrating PhotoVoltaic System in Denmark ... Test of a High Concentrating

Test of a High Concentrating PhotoVoltaic System in Denmark - A part of SOL 2000A

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0. Index 1. Intro........................................................................................................................................... - 3 -

2. Danish Resume......................................................................................................................... - 4 -

2.1. Det testede system.......................................................................................................... - 4 -

2.2. Potentialet ...................................................................................................................... - 4 -

3. Suppliers ................................................................................................................................... - 5 -

3.1. Choice of supplier .......................................................................................................... - 5 -

3.2. Supplier list – potential suppliers................................................................................... - 6 -

4. The concentrator...................................................................................................................... - 7 -

4.1. The Gira-sol System ...................................................................................................... - 7 -

4.2. The lenses....................................................................................................................... - 8 -

4.3. The Cells ........................................................................................................................ - 9 -

4.4. The Tracking system.................................................................................................... - 10 -

4.5. Technical specifications of the installed system.......................................................... - 11 -

4.6. Experienced difficulties with the concentrating system .............................................. - 11 -

5. Measurements ........................................................................................................................ - 12 -

5.1. Measurement equipment.............................................................................................. - 12 -

5.2. Data logging equipment............................................................................................... - 13 -

6. Evaluation of the concentrating system ............................................................................... - 14 -

6.1. Economic analysis ....................................................................................................... - 14 -

6.2. The stability of the system ........................................................................................... - 15 -

6.3. Recommendations........................................................................................................ - 15 -

7. The 21st European Photovoltaic Solar Energy Conference and Exhibition .................... - 16 -

8. Publishing of results............................................................................................................... - 17 -

9. Enclosures............................................................................................................................... - 18 -

9.1. Enclosure 1 – Datasheet with gathered data from the measurement equipment ......... - 18 -

9.2. Enclosure 2 - Press release, June 2006 ........................................................................ - 19 -

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1. Intro The purpose of the Test of a High Concentrating PhotoVoltaic System in Denmark project is to gather the first experiences with a photovoltaic concentrator system in Denmark and evaluate the potential for future installations in Denmark. Test of a High Concentrating PhotoVoltaic System in Denmark is a part of Sol2000A which is a development program for solarcells, financed by Energinet.dk. The program supports different projects which are all approved by the owner of the overall electricity and gas infrastructure in Denmark, Energinet.dk. All over Europe and the rest of the world there are new companies, which expect to be able to produce and offer high concentrating photovoltaic systems at a lower price than traditional flat panel PV systems. Most of the companies are at the moment in the final development phazes, making mass production an issue for the near future. The market for concentrators is rapidly growing. But the market is still mainly consisting of larger plants with a power of at least several hundred kWp or smaller demo systems installed for testing purposes at the developing companies and institutions. The system tested through this project is therefore one of the first installations of a HCPV-system installed for a customer in the world according to the supplier. During the testing period of the HCPV system, data is gathered, which can be used by Danish companies and institutions to evaluate the potential of the technology. The report is written in English because of the international interest for the results. A Danish summary can be found in the following chapter.

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2. Danish Resume Projektet Test of a High Concentrating Photovoltaic System har haft til formål at teste et HCPV – høj koncentrations solcelle system – og vurderer potentialet for teknologien i Danmark. Baggrunden for dette ønske er de potentielle priser, som producenterne forventer at kunne levere til. Da HCPV teknologien er udviklet til det sydeuropæiske marked kendes potentialet ikke for områder længere nordpå med lavere indstråling som f.eks. i Danmark. Markedet for producenter af HCPV systemer består i dag både af mindre iværksættere og koncerner samt videnscentre som f.eks. universiteter, der har præsenteret udviklingsprojekter og lover en produktion inden for en kortere periode. Igennem leverandørsøgningen viste det sig at der kun var et enkelt firma der var i stand til at levere et produkt på de vilkår, der var opsat i projektet. Projektet er en del af solcelle udviklingsprojektet Sol2000A. Sol2000A er støttet af Energinet.dk og har til formål at støtte en række projekter, der udvikler eller tester nye solcelleløsninger. 2.1. Det testede system Det spanske firma, Sol3g har leveret HCPV systemet. Dette projekt er den først kunde hos dette firma og ifølge leverandøren en af de først kunder i verden til et HCPV system. Derfor var leverandøren meget interesseret i at deltage i projektet for at samle erfaringer. Han nævnte samtidig en forventet international interesse, pga. de begrænsede erfaringer der eksisterer med HCPV installationer generelt. Dette er hovedårsagen til, at afrapporteringen er foretaget på engelsk. Der er leveret et 1 kWp system bestående af 28 rækker af 10 linsesystemer. Hvert system er opbygget af en 120 mm x 120 mm Fresnel linse, der koncentrerer lyset ned på et prisme, der igen sender lyset videre ned på en 5,5 mm x 5,5 mm højkoncentrationscelle med en effektivitet på over 30 %. Derved opnås ifølge leverandøren en teoretisk koncentration på 475 gange og en praktisk koncentration på ca. 400 gange. Der har i projektet vist sig at være en del problemer med produktet. Dette skyldes primært at det ikke er testet færdigt og at klimaet er anderledes end i Spanien, som produktet er udviklet i og til. Det forventes dog at disse problemer vil forsvinde efter lidt flere erfaringer er indsamlet. De data der er samlet er primært kommet i perioder med problemer, men på trods af dette er der målt en effektivitet på ca. 20 %. Leverandøren forventer at dette er det mest brugbare tal for effektiviteten. Da systemet stadig venter på at blive opdateret er dette dog endnu ikke bekræftet. 2.2. Potentialet Potentialet vurderes at være begrænset i Danmark, da de nyeste prisforventninger til en færdig installation ligger omkring de nuværende priser på et standard krystallinsk panel med samme ydelse. Hertil kommer en lidt større forventet produktion fra HCPV systemet, men til gengæld er der væsentlig flere usikkerheder ved dette system blandt andet på grund af flere sliddele og mere vedligeholdelse. I lande med flere solskinstimer forventes potentialet at være væsentligt større baseret på den større direkte indstråling der findes her.

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3. Suppliers A market analyse of concentrator systems was carried through in the opening faze of the project. The suppliers were identified through ”PHOTON International, 7/2005”, which deals with the CPV market, or through searches on the Internet, using search engines and different branch websites. After the potential suppliers were identified through the market analyse, a long range of them were contacted. During the period where the potential suppliers were contacted and screened it became clear that most of the companies were still developing their products. Because of this, the prices are generally very high, compared to the level they expect to be able to sell their product at when mass production is realized. Most of them are not able to deliver yet. Many of the companies have not answered emails with a request for a purchase of one of their system. The chosen supplier explains that most of the companies, including themselves, are concentrating their resources on the product development in the start-up phase, focusing less on sale and customer support. 3.1. Choice of supplier The supplier is chosen based on expected future sales prices, interest in the project, ability to deliver and install the system in Denmark and the product itself, which offers a very high concentration level. It was also an important factor that they could deliver a Turn-Key system to avoid problems. The supplier, sol3g, is a Spanish developing company which so far only produces for demonstration and testing purposes. The idea behind this project has made it interesting for Sol3g which is the reason why they have accepted us as their first customer.

Sol3g expects to be able to deliver and install HCPV systems at a price around 4,5 €/Wp when production reaches a higher level. A standard crystalline panel including tracker is today sold at prices around 6 €/Wp1 depending on order size. A production line is being finalised at the moment within the company, to produce these high concentrated photovoltaic systems. Sol3g is using high concentrated photovoltaic cells from the German company RWE Space Solar Power GmbH for the systems. The tracking system for this system is delivered by a Spanish sub supplier, FEiNA SCP. Another interesting supplier for the concentrator was MicroPV Inc. Their prices seem interesting, but they do not offer a Turn-Key system and they do not wish to handle the export papers from China, where the product is produced. These conditions make the economic issues very insecure in addition to the risk of incapability between the parts we have to identify and buy from different suppliers. Therefore a Turn-Key supplier is chosen to secure the project progress.

1 Global average installation price according to Solar Annual 2006 by Photon Consulting (www.photon-consulting.com)

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3.2. Supplier list – potential suppliers Some of the contacted suppliers identified in the project are listed below. Several other companies were contacted which did not offer a product that met our requirements to product specifications. An example of this is suppliers of combined photovoltaic and solar heating systems.

Supplier

Contact,

Website

Concentration-level

Status

Amonix www.amonix.com 1:250 No answer received on requests.

Solar Systems Russell Harris, www.solarsystems.com.au

1:500 Only deliver large plants in sizes from 350 kWp.

Edtek inc. Jörn Jürgens, www.edtekinc.com

1:800 Almost ready to produce. Communication terminated by supplier.

Solar Trackers V. Poulek, www.solar-trackers.com

2:3 Can deliver. Low concentration level.

Entech Solar www.entechsolar.com 1:100 No answer received on requests.

United Innovations www.unitedinnovations.com ? No answer received on requests.

Boing Spectrolab Raed A. Sherif, Ph.D, www.spectrolab.com

- Only cell manufacturer – recommends Sol3g

Energy Innovations Inc. www.energyinnovations.com 1:25 No answer received on requests.

Concentrix Solar GmbH Hansjörg Lerchenmüller, www.concentrixsolar.de

1:500 Communication terminated by supplier.

PYRON Solar, Inc Inge, www.pyronsolar.com 1:400 1, 5 kWp offered. Communication terminated by supplier.

Whitfield Solar Ltd www.whitfieldsolar.com 1:40 No answer received on requests.

Sol3G Ricard Pardell, www.sol3g.com

1:476 Can deliver. Chosen as supplier.

MicroPV Inc. George Huang, www.micropv.com

1:500 Fair price. Does not offer a complete system, installation and delivery.

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4. The concentrator The concentrator system is delivered as a Turn-Key system and placed at a flat roof on a large garage in Brædstrup, Denmark. The concentrator is installed at a solar tracker which follows the suns movement over the sky via two axes. 4.1. The Gira-sol System Sol3g has developed a small concentrating system, made for flat installations at ground or roof sites. The system consists of 200 Wp units which are easy scalable from a single unit to large plants made for installations. The standard Gira-sol system contains the concentrating system, including triple junction cells and a tracking system. The Gira-sol system consists in the standard solution of 10 rows of lenses concentrating the radiation at a 5,5 mm x 5,5 mm triple-junction photovoltaic cell. The features are listed in the figure below:

M40 Features

Cells per M40 module 10 Cells Total solar aperture 0,144 m2 Cell efficiency 35 % Module efficiency 28 % Voc 30 V Isc 1,51 A FF 87 % Wp at 1kW/m2 DNI 40 Wp Dimensions 1200x120x194 mm Weight 2,35 Kg

The Gira–sol system is developed to fit the Spanish conditions, where the sun is higher on the sky. This system can not be completely copied to be used in Denmark. As a 1 kWp system should be tested in the project, the supplier adapted their standard solutions to provide a special system for this particular project. The installation used in the project is described later in the report.

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4.2. The lenses The concentration is reached with 120x120 mm aperture positive aspheric PMMA Fresnel lenses combined with non imaging BK7 secondary optical elements. These provide a theoretic 476x geometrical concentration making a 400x practical concentration level according to the supplier. This optical system yields an efficiency around 85 %, excellent exit flux uniformity, and an acceptance half angle around 1,25 degrees. The primary optical elements are the P502 design, manufactured by compression moulding extruded PMMA sheet into rows of 10 lenses while the secondary elements are made using advanced glass moulding techniques.

Every concentrator unit contains a multi-junction 5,5 x 5,5 mm photovoltaic cell. Cells are mounted on a metallised ceramic substrate including a protective bypass diode, and are bonded to our S501 BK7 secondary elements. The cells are mounted on a metallised ceramic substrate, and the secondary optical element is attached directly to the cell. The secondary optics gives tolerance to the optical system and also homogenizes the flux and eliminates chromatic aberrations from the primary Fresnel lens. Thus, the system has a 1,25 degrees acceptance half angle. Concentrators are aligned in M40 sub-modules of 10 units, and these rows are enclosed by a U shaped aluminium sheet that acts simultaneously as row concentrator main mechanical structure and heat sinking device. Photovoltaic sub-mounts with attached secondaries are directly glued to the row sub-module structure using a heat transmissive epoxy. Heat dissipation thus takes place through the concentrator row sub-module aluminium sheet U body structure, yielding a very simple, efficient and economical solution.

The M40 sub-modules are composed by the U shaped structure, the photovoltaic sub mounts with attached secondaries, the connecting cabling between sub-mounts, and is enclosed in the front and sides by the extruded PMMA Fresnel lenses combined with an injection made low cost plastic frame. The U shaped aluminium structure and plastic frame-lenses combination are bonded together using a sealing component. Thus, the row sub-modules are completely watertight. A pressure compensation valve equalizes internal and external air pressure without allowing water entering the modules. Each M40 sub-module has combined conversion efficiency around 28% when using 35% efficient cells, delivering nearly 40 W less than 1000 W direct normal irradiance and 25 degree ambient temperature, thus making up to 192 W per module.

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4.3. The Cells The cells are manufactured by the German company RWE Space Solar which mainly delivers to the space industry to provide satellites with solar energy. These types of cells are relatively expensive, but very useful for a HCPV system as the cell area is very small. The cells used in the HCPV system are triple junction cells, actually constituted by three series connected sub cells of GaInP, Ga As, and Ge. They have a 5,5 mm x 5,5 mm active area. But as it has two bus bars that collect electrons in the front side, the total size including bus bars is 6,5 mm x 5,5 mm. Cell thickness is 0,15 mm. Triple Junction means in simple terms that the cell consists of three producing layers which exploit different wave lengths of the radiation from the sun. Therefore an approximately three times as large amount of the energy from the sun can be used.

4.3.1. Band gaps Detailed technical information of the band gaps is displayed below. The information is based on information from the supplier, Sol3g. The band gaps of the sub cells are the following: Top-cell, GaInP, Band Gap E (GaInP-gap) ca. 1,8 eV at room temperature Middle-cell, GaAs, Band Gap E (GaAs-gap) ca. 1,41 eV at room temperature Bottom-cell, Ge, Band Gap E (Ge-gap) ca. 0,66 eV at room temperature The generated current Isc in each sub cell are the following: Under AM1.5d conditions, one sun: Top-cell 12.3 mA/cm² Sol3G-design (5.5 x 5.5 mm² area) 3.7 mA Middle-cell 15.0 mA/cm² Sol3G-design (5.5 x 5.5 mm² area) 4.5 mA Bottom-cell 20.5 mA/cm² Sol3G-design (5.5 x 5.5 mm² area) 6.2 mA Under AM0 conditions, one sun: Top-cell 16.2 mA/cm² Sol3G-design (5.5 x 5.5 mm² area) 4.9 mA Middle-cell 16.5 mA/cm² Sol3G-design (5.5 x 5.5 mm² area) 5.0 mA Bottom-cell 27.7 mA/cm² Sol3G-design (5.5 x 5.5 mm² area) 8.3 mA

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4.4. The Tracking system Sol3g have developed their own tracking systems for their standard systems. As a special systems size is developed for this project, the standard tracking system does not fit. The supplier has therefore used a tracking system from the Spanish company, FEiNA SCP. As a solar concentrator only uses direct sunlight, it is necessary to use a solar tracker to follow the suns movement on the sky to reach a satisfactory production. The solar tracker follows the sun based on a program, which describes the suns movement. With this method, the tracker follows the sun even when clouds are covering the sky, making it ready to produce as soon as the sun shines through the clouds and always optimizing the angle for optimal production.

The tracker moves in two axes by the use of gear wheels; one which turn the system and one which tilts the system. Together they make sure that the system faces the sun at all times during daytime. It is possible to aim the sun simply by entering date, hour and latitude of the installed position in the controlling unit. After the installation the tracker will change position in intervals, set by the user. This installation repositions each ½ minute. At sunset, the solar tracker returns to the east position, near the horizontal (80 degrees from vertical). At sunrise, the solar tracker puts itself in vertical position. Afterwards, the solar tracker, continue the normal diurnal movement. When the modules are replaced after the deadline of this report, Sol3g wish to test a new type of sensor for the tracking system. The new sensor checks the position based on the direct radiation. This type should be more efficient and easier to set up.

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4.5. Technical specifications of the installed system In the present project a 1 kWp system has been tested. This is not a standard size, so a system was delivered which was developed especially for this particular project. The system was built of standard parts, put together to meet the requirements. The following table contains the information of the particular system.

Features for the installed system

Number modules (M40) 28 Cells per module 10 Total solar aperture 4,032 Cell efficiency 32 % Module efficiency 25 % Voc 210 V Isc 5,06 A FF 85 % Wp at 1kW/m2 DNI 1.006 Weight – including tracker Ca. 200 kg

4.6. Experienced difficulties with the concentrating system Because of the early product state and the fact that the tested system was one of the first of its kind in the world, a number of problems were met. All the problems were solved as they appeared and the supplier redesigned the production line to avoid future faults. 1.a. Water intrusion in the modules proved to be a major problem. The first delivery had

problems with water intrusion which were solved at site with glue. This was done as a temporary solution as the modules were to be exchanged with a higher quality.

1.b Before the second system was delivered, the production was optimized to avoid this problem. Despite successful tests in Spain these had the same problems with water intrusion.

1.c The third installed system is not expected to have any problems with water intrusion. 2. A sub supplier had problems with the delivery of the triple junction cells because of a large

demand. An alternative supplier was chosen. 3. The fine adjustment of the tracker proved to be difficult because of lack of sun. In order to

adjust the tracker a complete day of sunshine is necessary. 4. Because of the delayed delivery Sol3G chose to install a system with lower efficiency lenses

to make it possible for us to start the tests of the system. The system was later exchanged as planned.

5. The orientation of the optical elements did not seem completely alike in the second system

delivered. This was discovered during the orientation of the system towards the sun. 6. Data measurement has been cut off. The problem will be solved during the final installation.

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5. Measurements The data from the system provides information about the efficiency and potential of the concentrator in Denmark. 5.1. Measurement equipment The following measurement equipment has been used in the project to gather the necessary data. Variable Equipment Comments

DNI Tubed calibrated cell attached to tracking system

Measure of direct normal irradiance.

GNI Calibrated cell attached to tracking system

Measure of global normal irradiance. Diffuse component can be easily calculated without need of a third sensor if a low albedo is assured.

GHI Calibrated cell in fixed horizontal position

Measure of global horizontal irradiance.

Module temperature

Thermocouple Thermocouple attached to the back side of one or several modules.

Ambient temperature

Thermocouple

Ambient humidity

Humidity sensor

Array voltage and current

Specially designed electronic circuit

This electronic circuit should be attached to the module array output, before the inverter.

Inverter output power

Inverter SMA Sunny Boy inverters already include the necessary RS232C port and software for this and other data to be captured by a personal computer.

Electrical consumption

Cost meter Measure the electrical consumption through a complete run for the tracker

The measurements have given information about the efficiency of the system. To measure the efficiency of the solar cells and the concentrator the temperature (°C) and the radiation from the sun (w/m2) is measured as references. Together the gathered data should provide an image which can be used to evaluate the potential of a tracking system in Denmark.

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5.2. Data logging equipment To gather the data from the measurement equipment the following equipment is used: Equipment Comments

Data Capture Equipment Data capture system that reads the different analogical inputs, converts them to digital values, and transfers them to the personal computer.

Personal computer A personal computer linked to the system.

Data logging and monitoring software Software that collects the digital signals sent by the data capture equipment and the inverter to the personal computer, logs it, and also manages warning or critical conditions.

Internet connection This will allow the data logging software to periodically send emails containing the data logs to a remote site.

The data has been registered each 30 seconds. The data is then sent to a pc. Here the data are stored in an excel sheet where daily calculations have been gathered. The gathered data summoned pr. Day can be found in the enclosures (Enclosure 1). For more detailed data please contact the EnergiMidt A/S.

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6. Evaluation of the concentrating system The HCPV technology is mainly developed for an area with a large amount of direct sunlight why it was interesting to evaluate the potential for the technology in Denmark. A HCPV system only uses direct sunlight for energy production. In Denmark we have much fewer sun hours (1495 sun hours) with direct sunlight compared to Southern Europe (e.g. Valencia with 2538 sun hours). Therefore a relatively large part of the production from a standard flat panel in Denmark is based on diffuse sunlight reflected from clouds, the ground, and nearby objects. This energy can rarely be used for energy production in a HCPV system. The potential is expected to be greater in countries with more direct sunlight, but the project has shown that it is possible to produce energy from HCPV systems in Denmark at acceptable levels. 6.1. Economic analysis To evaluate the economic potential, the system is compared to a standard traditional flat panel PV system. The prices are based on cost prices. Freight is not included in the calculations.

SIZE 1 kWp HCPV – Project 1) Standard Flat Panel 2)

Price incl. mouthing system € 5 140,- € 3 160,-

Tracking system € 1 200,- € 0,-

Inverter € 550,- € 430,-

Installation € 2 000,- € 800,-

Total Turn-Key price (incl. discount) (Expected level)

€ 8 350,- (€ 4 500,-)

€ 4 390,-

Production in DK (Expected level)

363 kWh/year (984 kWh/year)

850 kWh/year

1) The prices are based on the purchase and the estimates from the supplier, Sol3g. 2) The prices for the panels and inverter are the lowest prices according to www.solarbuzz.com. Until now the production has been limited on the system due to problems with the lenses and the water intrusion. Based on the first month of production, the early production is estimated to reach 363 kWh/year if the problems continue. The producer has estimated the production to reach 984 kWh/year when the initial problems are eliminated, based on the measured radiation and reached efficiency of 20 % during the first month. A standard flat panel system fixed in 45 degrees due south is producing around 850 kWh/year in Denmark. If it is placed on the same tracker as the HCPV, the radiation is measured 23 % larger. Provided that the production increase follows the increase in radiation, the production for a flat panel installation on the tracker should be around 1043 kWh/year and thereby larger than the

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HCPV system. But considering the increased investment, the payback time is expected to be the same as a flat panel system. With the current price level there is no potential for HCPV in Denmark. If the expected goals are met for system price and production prices the potential is better but still not low enough to compete with a flat panel system. 6.2. The stability of the system In the project a number of problems have occurred. The problems have mainly been related to the fact that it is a new product which has only been tested in a limited time and only in Spain. Some problems related e.g. to climate differences. The problems were in the production line and have caused a change in procedures avoid the problems in the future. It is expected that the initial problems met in this project will vanish after a few more systems are installed at different sites and the production is optimized. An unclarified uncertainty regarding HCPV is the lifetime of the systems. As the experience on this area is very limited at the moment it is hard to evaluate how e.g. the cells will be affected by the high concentrated radiation. Problems with the lifetime could be the heat from the concentrated sun and the stability of the different materials used in the system as well as in the production line. 6.3. Recommendations The technology is showing great potential and when the initial problems are overcome it is expected that HCPV will be used in many countries. But as shown in the economic analysis, the tracking system seems to hold only a limited economic potential compared to a traditional flat panel system in Denmark. In addition to this the technology is still very insecure as the product is in the early stages and no long term tests therefore have been made. In countries with more direct radiation the potential is significantly larger and it must be expected that the customers for this technology are mainly found south of Denmark. The first readings which were done before the problems started showed great potential. The supplier is of course not happy about the results so far, because of all the initial problems which they did not meet in the tests in Spain. The problems are expected to be eliminated with the exchange of the modules within October 2006. The manufacturer mentioned some problems with general inverter configurations as inverters today are not optimized to production based on direct sunlight. This is due to the fact that the voltage will raise and fall more often with direct sunlight caused by passing clouds as the diffuse sunlight can not be gathered by the HCPV. Every time the inverter shuts down because of a voltage drop you experience a start up time beyond 40 seconds. According to the Danish inverter producer, Powerlynx, there are requirements today, requiring that the inverter does a 30 second grid test.

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7. The 21st European Photovoltaic Solar Energy Conference and Exhibition At the 21st European Photovoltaic Solar Energy Conference and Exhibition held in Dresden in September 2006, four concentrators were presented. Three of these were contacted in the initial phases of this project. A major manufacturer, Sharp, were also presenting a new concentrator which is an indication of the potential of the technology in a larger scale.

The system above is presented by SCHOTT Solar. The system consists of very small units of concentrators compared to the tested system

The only company which was able to deliver a concentrating system was Solar Tracker which only offers a concentrating level of 2:3. As it is not a HCPV system, it had no interest in this particular project. The fact that no companies could deliver a HCPV system underlines the level of news in the project. The three HCPV systems which were present in Dresden were SHARP Electronics, Concentrix Solar and SCHOTT Solar.

SHARP Electronics presented the system seen to the right. It was still in the early phases of development.

The System from Concentrix Solar is displayed to the left. Only a small model was shown at the fair.

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8. Publishing of results The project was published by a press release in Denmark, in June, 2006 which informed about the installation of the system. The press release can be found in Enclosure 2. The purpose of the project is to provide public available information about a HCPV system and the potential for an installation in Denmark. Therefore the result will be available to download, as well as by contacting the project leader, EnergiMidt. The report is available at www.solstroem.net. The report and additional information can also be acquired by contacting the project manager, EnergiMidt A/S, + 45 7015 1560.

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9. Enclosures 9.1. Enclosure 1 – Datasheet with gathered data from the measurement equipment

Date Collected energy

Specific collected energy

DNI GNI GHI Max power Efficiency GNI/DNI

kWh kWh/m2 kWh/m2 kWh/m2 kWh/m2 W % 20060805 4,81 1,19 18,42 22,03 13,01 660,21 6,47% 1,2020060806 0,77 0,19 4,61 6,39 3,94 252,558 4,12% 1,3920060807 0,13 0,03 0,44 3,07 3,05 452,088 7,48% 6,9520060808 2,89 0,72 5,54 8,01 4,79 637,637 12,95% 1,4420060809 0,80 0,20 1,75 4,49 3,60 628,544 11,42% 2,5720060810 2,92 0,73 5,76 7,90 5,38 547,312 12,59% 1,3720060811 1,20 0,30 2,97 5,52 4,06 481,873 9,98% 1,8620060812 0,10 0,02 0,24 1,35 1,40 335,464 10,18% 5,7220060813 0,04 0,01 0,45 2,33 2,14 127,652 2,43% 5,1620060814 0,04 0,01 0,21 1,93 2,17 254,606 4,57% 9,1320060815 0,11 0,03 0,69 2,72 2,72 364,14 4,12% 3,9420060816 1,19 0,29 4,13 6,88 4,41 296,712 7,13% 1,6720060817 0,76 0,19 3,89 6,86 4,57 241,296 4,88% 1,7620060818 0,75 0,19 3,09 6,11 4,56 240,84 6,05% 1,9820060819 0,33 0,08 3,07 8,78 7,41 234 2,66% 2,8520060820 0,82 0,20 2,63 4,91 3,73 385,953 7,71% 1,8720060821 0,45 0,11 2,19 5,10 3,85 369,6 5,07% 2,3320060822 0,35 0,09 2,12 4,47 3,39 263,168 4,10% 2,1020060823 0,07 0,02 0,61 3,09 2,76 239,7 2,67% 5,0720060824 0,83 0,21 3,92 6,52 4,37 292,336 5,25% 1,6620060825 1,12 0,28 5,19 7,50 4,59 215,6 5,37% 1,4520060826 0,54 0,13 2,49 5,07 3,60 212,85 5,41% 2,0420060827 0,12 0,03 0,86 2,98 2,50 150,87 3,43% 3,4620060828 1,44 0,36 6,01 8,21 4,58 328,322 5,95% 1,3720060829 0,42 0,10 2,30 4,55 3,28 200,928 4,53% 1,9820060830 1,36 0,34 5,45 7,33 4,44 334,704 6,20% 1,3420060831 0,77 0,19 4,61 6,39 3,94 252,558 4,12% 1,3920060901 0,15 0,04 1,22 3,25 2,35 169,533 3,03% 2,6720060902 0,14 0,04 1,31 3,16 2,79 155,54 2,69% 2,4120060903 0,15 0,04 1,79 3,73 2,99 187,275 2,15% 2,0920060904 0,50 0,12 3,40 5,80 3,69 240,146 3,64% 1,7120060905 0,41 0,10 2,64 5,35 3,48 267,915 3,85% 2,0220060906 0,00 0,00 0,07 1,25 1,50 16,8 0,96% 18,6920060907 0,16 0,04 2,25 4,33 3,14 177,762 1,74% 1,9320060908 0,81 0,20 6,89 8,77 4,61 255,204 2,90% 1,2720060909 0,43 0,11 3,30 5,63 3,37 226,512 3,24% 1,7020060910 0,48 0,12 5,07 7,16 4,14 208,824 2,35% 1,4120060911 0,38 0,09 5,50 7,62 4,31 160,664 1,72% 1,3920060912 0,35 0,09 6,07 8,13 4,28 126,344 1,42% 1,3420060913 0,36 0,09 6,71 8,63 4,27 116,145 1,33% 1,2920060914 0,29 0,07 6,45 8,51 4,20 108,345 1,13% 1,3220060915 0,18 0,04 5,10 7,40 3,88 50,685 0,87% 1,45

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9.2. Enclosure 2 - Press release, June 2006 Danmarks første bevægelige solcelleanlæg Det første bevægelige solcelleanlæg er netop installeret på dansk grund. Det nye anlæg adskiller sig fra traditionelle solcelleanlæg ved at følge solens bane på himlen og har desuden linser, som koncentrerer solstrålerne på små højeffektive solceller. Solceller er normalt sammensat i flade paneler, som typisk er fastmonteret på tage. Det nye solcelleanlæg, som netop er installeret hos det midtjyske energi- og bredbåndsselskab EnergiMidt, er derimod placeret på et bevægeligt stativ (sun tracker). Det vil sige, at anlægget hele tiden følger solen, så solens energi udnyttes optimalt. Dette er med til at give en meget høj virkningsgrad. Ved at benytte en højeffektiv solcelle, som er opbygget i 3 lag (triple junction), er det muligt at udnytte en større del af sollysets energiindhold. De nye solceller har således potentiale til at omsætte op til 38% af solens energiindhold til elektricitet – hvilket er væsentlig bedre end hidtidige anlæg. Den meget høje virkningsgrad på anlægget gør, at der skal anvendes mindre materiale (solcelle silicium) i forhold til traditionelle solceller. I det nye solcelleanlæg, som EnergiMidt netop har installeret, koncentreres lyset ved hjælp af linser. Linserne fanger solen og koncentrerer lyset ned på solcellen igennem en prisme. Ved at koncentrere sollyset opnås en 400 gange større el-produktion fra solcellen og dermed et væsentligt mindre materialeforbrug. Solcelleanlægget hos EnergiMidt er et af de første af sin art i verden, der er installeret hos en kunde. Kombinationen af de tre teknologier forventes at bidrage til en væsentlig højere effektivitet i forhold til traditionelle solcelleanlæg. Ud over effektivitet er der også økonomiske fordele ved det nye solcellesystem. Producenten regner med, at anlægsprisen på sigt kan nå 2 euro pr. watt, hvilket er væsentlig under de nuværende fremtidsudsigter for den traditionelle solcelleteknologi. Perspektiver Med projektet, som er delvist finansieret af Energinet.dk, skal EnergiMidt teste, hvordan et anlæg som dette fungerer i de nordlige himmelstrøg. Anlægget producerer kun elektricitet ved direkte solindstråling. Derfor er anlægget naturligvis bedre i lande med mange soltimer. Alligevel kan en evt. kommende lav pris på anlægget gøre det interessant at benytte i Danmark. Erhvervschef Flemming Kristensen, EnergiMidt, fortæller at afprøvningen af det nye solcellesystem er i tråd med EnergiMidts strategi om at deltage i udviklingen af fremtidens energi-teknologier. EnergiMidt vil gerne deltage aktivt i introduktionen og demonstrationen af nye alternative energiformer på markedet. Herigennem får vi testet og udviklet de løsninger, der på sigt har potentiale for at være konkurrencedygtige med den traditionelle energiforsyning. Yderligere oplysninger og information om solceller og solcelleanlæg fås hos ingeniør Carl Stephansen, EnergiMidt, på tlf. 99 26 83 04. Fakta Solcelleanlægget er en helt ny type af typen HCPV. Det er det spanske firma sol3g, som har stået for levering og installation.

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Kort om EnergiMidt EnergiMidt er det lokale og kundeejede energiselskab for 162.000 kunder i det midtjyske område. Samtidig arbejder vi i øjeblikket på at blive midtjydernes foretrukne valg inden for bredbåndsbaserede kommunikations- og underholdningsydelser som Internet, TV og telefoni. På el-området er det vores fornemste opgave at sikre en stabil elforsyning, konkurrencedygtige elpriser og yde optimal service for vore kunder. På bredbåndsområdet er vi i fuld gang med at etablere et fiberbredbåndsnet i det midtjyske område. Et net, der giver alle kunder mulighed for et væld af bredbåndsydelser som lynhurtigt Internet, spændende nye Tv-kanaler og attraktive telefonitilbud. Alt sammen via én fremtidssikret bredbåndsforbindelse, som kan øges efter behov, f.eks. helt op til 100Mbit/s. Vi er desuden meget aktive inden for områder som energirådgivning, elinstallation, salg af varmepumper og solvarme- og solcelleanlæg.

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