A specific integrated group of AC/DC converter, inverter and static switch (see figure 1), with particular technical solutions to supply the Hybrid System the necessary safety and reliability characteristics has been purposely developed by SIEL with the contribution of ENEL.

In normal conditions, the photovoltaic field and the battery storage deliver power on a DC bus and inverters, that play in redundant parallel, generate the grid. The diesel generator is connected to the DC bus via controlled rectifiers but it can directly feed the grid through a by-pass switch.

The PLC control will optimise the PV generator contribute and assure the best continuos service through the management of the battery storage and of the diesel generator.

The appropriate sewage management is the second important problem, which has to be solved. As we have mentioned earlier, we have gray water as sewage only. Almost the whole content of nitrogen — compounds originates from black water, which is eliminated in our case. In our case the household sewage contains water from the kitchen and from the bathroom only. So, our sewage contains only remainders of soap and different tenzio active materials. This materials can be decomposed easily through biological method. This water is collected into a large tank and cleaned with the help of microorganisms. The wasted water is circulated and aired with the help of an electrical pumps. Solar cells supply the electrical energy for these pumps. We have installed four moduls of amorphous silicon solar cells type DS40 maden by Dunasolar [3]. These solar cells serve not only as power supplies but serve as shadowing over the windows, too.

References

[1] A. Nemcsics; KukaBuvar IX 2003/4 pp. 16-17 (in Hungarian)

[2] A. Nemcsics; KukaBuvar X 2004/1 pp. 14-16 (in Hungarian)

[3] www. dunasolar. hu

Christiane Egger, O. O. Energiesparverband Christine Ohlinger, O. O. Energiesparverband LandstraRe 45, 4020 Linz T: +43-732-7720-14380, F: -14383 E: office@esv. or. at, I: www. esv. or. at

Presently, 674,000 m2 solar thermal were installed in the region of Upper Austria which is nearly 0.5 m2 per inhabitant (488 m2 per 1,000 inhabitants). In total 230 million kWh heat are produced annually and the Upper Austrian companies account for a quarter of the annual turn-over of the Austrian solar industry of about 121 million €.

This favourable development is a result of the Upper Austrian solar campaign carried out by the regional energy agency O. O. Energiesparverband. However, the successful market development so far took place mainly in the residential sector with every third newly built one family house being equipped with solar thermal collectors. The solar campaign aims therefore at bringing this development also to the large-scale solar market including a number of activities ranging from awareness raising activities and training to subsidies and new professions.

Purpose

In Upper Austria, renewable energy sources (RES) provide 30 % of the primary energy consumption. This high level of market penetration is due to a clear political commitment and based on an integrated action plan. O. O. Energiesparverband, the regional energy agency of Upper Austria, is responsible for the implementation of most of these measures included in the energy action plan.

Methods

The first solar target was set in 1993 to reach an installed surface area of solar thermal collectors of 300,000 m2 until 2000.

By 2000, the new energy strategy "Energy 21" set a further target of 1,000,000 m2 solar thermal collectors by 2010 — equalling nearly 1 m2 per inhabitant!

Approach

A number of programmes are implemented to further increase the market share of solar energy by creating a demand for solar energy products & services and by supporting the market in meeting this demand. The mix of measures comprises information & awareness raising activities (internet, workshops, training), competitions (regional solar league), energy advice (for private households, public buildings, companies), training & education (launching two new educational schemes for jobs in the RES sector) and financial support (including a TPF programme).

While current conditions are still adverse for a broad implementation of solar collective systems in the multifamily housing sector, the following factors are important for a successful project:

— Integrated Approach: The installation of a solar collective system has to be integrated in a new building construction or a refurbishment at an early point of time. Realising synergies in the planning and installation process and help to reduce costs and maximize results.

Services: Housing Companies mostly are not experienced in integrating solar collective systems and do not have the time to deal with more complex technical solutions. Suppliers have to provide all necessary steps to integrate a solar thermal system.

Energy Services: A good way to integrate a solar collective system into the energy supply of a multifamily building is by integrating it into contracting models. In these cases a professional energy service company takes care of all technical and and framework details and can act as a full service provider for the housing company. By its specific Know how, the energy service company is able to run the system at an optimum.

Guarantees: Due to still existing distrust about the efficiency of solar collective systems it seems necessary to provide quality assurances like guaranteed solar results for large systems. Automatic control systems are very helpful to detect malfunctions as early as possible. Therefore high quality products are a prerequisite.

Marketing: Applying solar technology at housing complex can improve the buildings and housing companies’ image. Avoiding vacancies and frequent change of tenants reduces the direct costs for housing companies. Especially in weak housing markets this topic should be strategically used to foster the decision about implementing solar systems.

5 Further Demand

Taking into accout the political goal of installing 100 million m2 solar thermal collector area until 2010 in Europe, this will only be achievable, if a considerable share is installed in solar collective systems in the next years.

Therefore, it is necessary to continue clearly focussed information and know-how transfer activities, adressed to housing and real estate companies as the main target group for solar collective systems for hot water and space heating applications. Europewide, decision makers in this industry have to be informed about chances and ways to implement solar technology.

In order to boost this market, the main and general problem of poor economic prospects has to be targeted and mitigated by efficient financial support mechanisms that foster highly cost and energy efficient large scale applications.

Aharon Roy/Department of Chemical Engineering/Ben-Gurion University, P. O. Box 653, Beer-Sheva 84105, Israel. <rovaaron@baumail. bau. ac. il>

Phone: +(972)8-646-1484; Fax: +(972)8-647-2916.

Introduction

A major driver of renewable energy is its use as a means of reducing greenhouse gas (GHG) emissions associated with energy generated from fossil fuels. The reduction of GHG emissions is linked to financial incentives, and fuel avoidance becomes a key design criterion. Renewable-hybrid systems have the potential of playing a decisive role in massive supply of renewable energy in the near-term, creating new markets and accelerating systems deployment while driving costs down. However, the hybridization of renewable energy with fuel-fired generators has to be appropriately designed; otherwise, environmental goals may be missed. In some cases the absolute quantity of the environmental benefit (fuel avoidance) generated by the renewable subsystem may significantly decrease or even be erased by the fuel subsystem in the solar-fuel hybrid plant. There is a problem to elucidate and solve. It will help perfect the global strategy of expanding the use of renewable energies.

Green energy and GHG control

The term "green power” has come to signify electricity generated from renewable energy sources like wind, hydropower, solar, geo-thermal and bio-mass. The key point is that every kilo-Watt-hour electricity (kWhe) generated from a renewable energy source is a kWhe that need not be generated from fossil or nuclear source [1]. Namely, every green kWhe output replaces a fossil-derived kWhe; and thus must decrease the use of fuel by the amount needed for producing one kWhe. The task of green power is to reduce various kinds of pollution and also slow down the dwindling of world fossil reserves. Thus, green power fosters a sustainable world. Various technologies are being developed worldwide for intensifying the effectiveness and economics of renewable energy systems.

In 2001, LABSOLAR, together with the National Renewable Energy Laboratory (NREL) and the Arizona State University (ASU), designed a 4-year experiment to assess the performance of a-Si devices operating in different climatic conditions. Three identical sets of commercially available a-Si PV modules from five different manufacturers were simultaneously deployed outdoors in

three sites with distinct climates (Site A — NREL: Golden, Colorado-USA, climate: dry continental, with cold winters and warm summers, Site B — ASU PV Testing Laboratory: Mesa, Arizona-USA, climate: dry desert, with cool winters and hot summers and Site C — LABSOLAR: Florianopolis — Brazil, climate: moist maritime, with warm winters and hot summers) in a round robin exposure experiment.

The experiment aims to determine the light-induced degradation and stabilisation characteristics of a-Si regarding specific history of exposure, and to monitor and compare degradation rates in different climates. Figure 10 presents results from the first year of measurements, showing, for four different a-Si PV module manufacturers, that modules deployed at the site with the highest minimum operating temperature experienced the highest stabilised output level. Each PV module set is deployed outdoors at one site for 12 months, is shipped back to NREL for measurements under a SPIRE 240A simulator at STC, is then sent to the next (second) site in the second year; and to the remaining site (third) in the third year, before being sent back to the original site were it was first deployed outdoors for a final deployment period. Every permutation of sites includes STC measurements at NREL. More detailed results have been presented elsewhere [6].

Simakin V. V., Strebkov D. S.,* Tyukhov I. I.*

All-Russian Institute of Electrical Engineering, Moscow, Russia *All-Russian Institute for Electrification of Agriculture, Moscow, Russia

Introduction

This paper describes the evolution of the silicon multi-junctional solar cells with vertical p-n junctions (SCVJ) and its present status, mainly, at the base of researches carried out in Russia and the USA. The number of SCVJ produced in the whole world is quite low in comparison with the traditional SC. At the same time according to the laws of technical cenosis (as in biology — biocenosis) increasing of unification and size of SC leads to increasing economic efficiency of solar energy and, yet, diversification (developing and creating other types of SC, and other principles) leads to higher competitiveness and occupying new niches [28].

1.3 Experiment

A digitized infrared (IR) image of an object can be directly related to the temperature distribution across the object and have also been to study surface temperature in PV modules by various authors [15][16]. It is difficult to directly measure temperature distribution of solar cells immersed in liquid because silicone oil may absorb infrared radiation to a certain extent. System configuration was changed to put solar cells above liquid. Then an IR thermographic analysis can be used to obtain temperature distribution of solar cells. It was performed with an Hy-2001G camera (measurement range -20 to 500°C, accuracy ±2% of range, thermal sensitivity 0.07°C and uncooled focal plane array detector). IR pictures were taken from the front of solar cells. Fluid enters the channel from one corner of solar cell to opposite corner. The geometric concentration ratio of system is 70 and the cell type is polysilicon solar cell.

1.4 Results

The variation of temperature distribution of solar cells with different fluid velocity is depicted in Fig.9 and Fig.10. It is evident that temperature distribution is highly no-uniform on the solar cell surface due to fluid flow and there are large temperature differences especially under concentrated sunlight from inlet and outlet. Local high temperature in Fig.9 and Fig.10 seems relevant to imperfection of crystal lattice and flow channel. Franklin et al [17] present that the both non-uniform light distribution and temperature distribution further cause the reduction of solar cell efficiency. Further research is needed to investigate the effects of no-uniform temperate distribution on the solar cell performance. ANSYS (finite element analysis program) is used to predict the temperature distribution at the same operational parameters of Fig.9 and Fig.10. The results are shown in Fig.11 and Fig.12 that are similar to infrared image (Fig.9 and Fig.10).

2. Conclusions

The steady-state thermal model is used to predict the average of solar cells immersed in silicone oil. Results show that the solar cells temperature increase with the increase of irradiance and inlet fluid temperature. This kind of immersion operation of solar cells is suitable for photovoltaic concentrator because they can provide an effective method of cooling solar cell under concentrated sunlight. Cooling of force convection is more effective method than free convection, but it may increase system cost. The IR thermographic analysis is used to obtain the temperature distribution of solar cell. Further studies are needed to probe the effects of no-uniform temperature distribution on the solar cell performance and find effective method to reduce no-uniform temperature distribution.

NOMENCLATURE

A area(m2)

E electricity(W)

G irradiance(Wm"2)

T temperature(K)

h heat transfer coefficient(Wm"2K"1)

c specific heat(Jkg"1K"1)

m mass flow rate(kgs-1)

v wind velocity(ms-1)

w fluid velocity(ms-1)

[1]

Fig.2 Thermal network for PV system of Fig.3 Thermal network of PV system of

forced convection cooling free convection cooling

inlet fluid temperature(K)

Fig.5 Temperature vs. inlet liquid temperature m=0.9kg/s, G=1000W/m2 Ta=298K

SHAPE * MERGEFORMAT

SHAPE * MERGEFORMAT

The search into policies in relation to the energy performance method that can encourage the use of RES has resulted in a collection of existing and non-existing policies. Three types of policy instruments have been distinguished: regulatory instruments, financial policy instruments and information policies. Policies for both new dwellings and existing dwellings have been searched for. Figure 7 presents existing and new examples of regulatory policies that could be combined with energy performance regulations for new buildings and/or energy performance methods for existing buildings in order to encourage the use of RES[28].

Figure 7 Regulatory instruments in relation to energy performance regulations that could encourage the use of RES

Financial incentives are used quite often by governments to encourage energy saving or use of RES. Financial incentives can have two directions. One is to impose levies or taxes to prevent undesired behaviour or to compensate for environmental costs and the second is to encourage desired behaviour by providing subsidies or tax exemptions. In an ideal situation these two types of financial incentives are in balance with each other: costs of RES subsidies are paid by revenues from taxes or levies on the consumption of non renewable energy. In The Netherlands, a levy had been imposed on energy use of
households of which revenues are used for subsidies for e. g. solar collectors and photovoltaic panels. Financial incentives are often part of schemes that function separate from energy regulations. Administrative procedures can be complex and can discourage the use of e. g. subsidies. It seems therefore interesting to see what financial RES incentives can be thought of in combination with the energy performance regulations that will have to be implemented according to the EPBD. Figure 8 presents a number of existing examples and new ideas[29]. Since the Build-On-RES objective is to encourage the use of RES, here mainly positive financial incentives such as subsidies or tax exemptions are discussed.

Figure 8 Financial RES incentives in relation to energy performance regulations that could encourage the use of RES

Information policies use a rather limited amount of force but try to convince parties just by providing information about the benefits of certain behaviour. Information policies are often considered to be tools that are additional to other policy instruments such as regulations or financial incentives. However, in case of situations where parties are in principle willing to change behaviour but where they do not have the knowledge about what behaviour is best, information policies can be an effective means. Figure 9 presents a number of existing examples and new ideas[30].

1. Conclusions

The Build-on-RES project has aimed to develop the methodological and contextual framework for the maximum incorporation of RES in an Energy Performance Policy both for new and for existing residential buildings. The methodological framework for a RES oriented Energy Performance (EP) Building Code presents approaches that are available to encourage the use of RES within the calculation of the energy performance of a residential building. An overview of existing approaches in EU member states for calculating the contribution of RES techniques has been presented. An overview of features of these calculation principles allows for comparing their characteristics. The contextual framework for a RES oriented EP Building Code describes the possibilities for encouragement of RES in the context of the introduction of energy performance policies. Combinations in terms of policies encouraging the use of RES and energy performance regulations have been presented. Policies distinguished are regulatory policies, financial incentives and information policies. A number of possible combinations of stimulating RES policies with energy performance regulations that do not yet exist are mentioned. By means of listing pro’s and con’s of the different options possible, it is possible to compare approaches. The contextual and methodological framework for a RES oriented Energy Performance Building Code hopes to provide the essential information for (re)designing energy performance regulations in such way that a maximum encouragement for RES can be provided when implementing energy performance regulations.

Acknowledgements

The results were gathered in the framework of an Altener project and based on the work done in the Build-On-RES project. The authors want to thank the following persons for their co-operation and contributions in the Build-On-RES project: Claudia Boon (OTB Research Institute, The Netherlands) Roel De Coninck (3E, Belgium) Bart Poel and Gerelle van Cruchten (EBM Consult, The Netherlands), Linda Sheridan and Michelle Foster (University of Liverpool, United Kingdom) and Carol Buscarlet (CSTB, France). More information about the Build-On-RES results can be found at www. buildonres. org

The prerequisites for a photovoltaic facility on the waste site are its stability and preservation of the surface sealing. Therefore, the city of Fuerth commissioned a geotechnical survey in Dec. 2000 and this in turn, brought the proof that the construc­tion of a photovoltaic facility was possible. A supplementary report from October 02, which referred to a total area coverage of 1.7 ha, came to the conclusion “that the stability and serviceability of the waste site’s surface sealing is suitable for the current planning.”

Finally, the same conclusion was also reached in an inspection report by the Nurnberg Office of Regional Industry within the framework of the Construction Licensing Procedure.

Constructional set-up and soil protection

The PV-installation encompasses approx. 5,600 solar cells from the company Sharp. Eighteen solar cells are mounted to each module table which is then anchored into the ground. Approx. 350 module tables were mounted on the south slope of the waste site. The determined layout of the foundations was calculated so that a snow load of 75Kg per square metre could be carried. For secure hold against arising wind drag, the foundations were calculated by a 1:5 safety ratio. The material chosen for the substructure was hot galvanized steel.

To convert the direct current generated by the solar modules into conventional net­work, alternating current, central current converters from the company Siemens are used which are built at the work in Fuerth. A maintenance contract guarantees the electricity input for a 20 year period.

The following preventative measures were met in order to counter potential soil ero­sion:

■ The module surface of the photovoltaic-installation will not be constructed as a continuous, closed surface; a loose superstructure is planned.

■ Maintenance paths go vertically from the bottom to the top area of the photo­voltaic-installation; a strip of width 1.6 metres will remain between each verti­cally aligned row of modules.

■ A distance of at least 5 centimetres will be kept between the module tables in a row.

■ The module table does not have a continuous, closed surface; each module is drained via gaps between the individual cells, thereby distributing rainwater extensively.

■ The loose “superstructure” of the waste site’s surface and the height of 1.5 metres from the solar module to the ground, lets sufficient diffused light reach
the ground surface under the modules; this also allows a layer of vegetation under the modules which acts to prevent erosion.

■ In addition, a grass/herb-seed mixture especially for shady locations is used.

■ Sheep grazing is planned in caring for the vegetation; if necessary, the mechanical cutting of the areas under and between the modules is possible.