The PV plant has been sized to ensure 100 kWp, at STC conditions, and, on the basis of the valuations carried out on the availability of the solar source in the place, in order to concur to distribute medium approximately 100′ 000 kWh in a year in AC current.

The energy conversion system is based on power conditioning units designed taking into account electrical characteristics and requirements for modularization and standardisation. The components are combined into supply systems, which fulfil the expandability, compatibility and flexibility requirements.

Each of the three power conditioning units consists of AC-DC converter, inverter and static switch with useful power, at inverter output, of 50 kW.

A large battery storage, consisting in 200 elements with C10= 3000Ah capacity, and a back-up diesel generator with a rated power of 160kW, will ensure customers energy supply reliability. The back-up diesel generator will run only in case of low battery or system breakdown.

The estimated hours of operation of the diesel generator are somewhat limited, only 180 hours annual equivalents, since it will be turned on only for emergency reasons, in case of system breakdown, and subsequently to long periods of insufficient production of the PV source, to satisfy the requirements of the community, for tips of energy demand or extended period of low solar radiation.

One of the most important problems of the sewage cleaning of the household is the mixing of the different originated dirty waters. The water from bathroom, called gray water, contains mainly remainders of soap and different tenzio active materials. The water from the toilet, called black water, contains different nitrogen-compounds such as proteins. The mixing of these waters is disadvantageous. The tenzio active materials hinder the demolishment of the proteins and the nitrogen-compound such as ammonia hinders the demolishment the remainder the soap. The solution should be the separate management of this wasted water. You can either use two drain­pipes or you can eliminate the black water with the help of a compost toilet. The compost toilet has many kinds. Their types spread from the outdoor back house to the indoor equipments. Most of the indoor compost toilet are very large and across — levels constructions. The small size transportable things have to be emptied in one or two days. The frequent servicing is the disadvantage of these equipments. We introduced a small, simple and portable compost toilet. Our alternative compost toilet needs almost no service. It is enough to empty it every two-three months depending
on the number of the users. The basic part of this toilet is a commercial thithy litre plastic tank. The setting in of the ratio of nitrogen and carbon is as usually by shawings. The complete equipment can be made very easily at home (Fig. 1). These portable things, we introduced just two years ago, are small and very simple. During the using time we have not had negative experiences with the use of these things. The equipment is still scentless even if we do not empty it for several months (Fig. 2). This year an action has been started (among „eco-people" in Hungary) to collect further experiences concerning this toilet [2]. The equipment is shown in Fig. 1 and 2. The detailed description of this new kind of compost toilet is in Ref. [2]. The contents of the tank can be implanted with compost. It can be proved by the fact that, there are many earthworm in it. After one or two months, this material becomes totally compost, which can be mixed to the compost-hill.

Due to various possibilities, application of solar cells in consumer goods is in fact the most interesting. This is where the rule of increase of sale and revenues due to low prices should be confirmed. Before determination of priority application, one should focus on summer season and season activities related to protection against overexposure to solar effects.

Attention should be paid to manufacture (adjustment) of parasols with portable solar ventilators, protective caps and hats for beach and work in the fields, bicycle lights, solar camping equipment, wrist and street watches, toys for children, walkman, mini computers, mobile phones of new generation, fan’s equipment, mini ventilators for car interior, etc.

Due to practically unlimited number of applications, this segment of market is estimated as very attractive so that it is predicted that in further analysis it will have an important role (Table 10.).

From Tab. 10 it is obvious that, after initial suspicion of the buyers and realization of only 36 kW in 2006, already in next (2007) year a real "boom" (362 kW) will follow which will last during the year 2008 as well (even more 0.6 MW)! During next year, anticipated annual volume of sale of solar cells in the systems of consumer goods would be normally reduced to level of 350 kW in 2010 year.

The data of the next table, given in two-year intervales, summarise our story about future solar cells application in SCG per market segments.

Obviosly, the market for solar cells application in Serbia and Montenegro is small, but empty. The ancitipated ammount of 3,9 MW in 2010. year, will be very litle 0.2% of the PV World Market Forecast (2000 MW), but whatever happens in the short term, the long­term outlook for the solar cell sector remains positive. [12].

In order to overcome existing barriers, it is neccessary to integrate the implementation of solar collective systems into broader refurbishment measures or new building constructions. Due to current market conditions in Germany the major focus in the housing industry has to be a sustainable refurbishment strategy for the existing building stock. Subsequently, two successful examples are presented briefly.

In 2001 the Berlin based housing company DEGEWO realized a refurbishment project at a multifamily building with 139 dwellings in Berlin-Wedding. The project included the installation of a solar collective system with 165 m2 collector area, the renewal of one boiler (now condensing boiler) and the existing central hot water system, a fuel switch from oil to natural gas and the refurbishment of the roof, including insulation of the flat roof.

Due to the integration of the measures mentioned above, the whole project has been implemented without an effective rent increase for the tenants, but only a shift between rent and running costs. The housing companie was able to allocate the solar investment to the rents, refurbish the building with an exceptionally high support from the tenants and to lower the running costs permanently. The latter is an important aspect in week markets with according competition.

Both, the housing company DEGEWO (“Klimaschutzpartner 2002”) and the solar company Parabel (“Deutscher Solarpreis 2002”) were awarded for this exemplary project.

Also in 2002 the Landesentwicklungsgesellschaft North Rine — Westphalia (LEG — NRW) started to refurbish and modernize an urban area in Gelsenkirchen constructed in the 1950th. The complex refurbishment included complete insulation measurements of the building envelope, new insulation glazing and the renewal of the heating systems. Besides new boilers, today also integrated solar roof collectors generate heat for the set up small district heating systems.

The project was partly funded by the 50 solar colonies program. Nearly all tenants, facing a small increase of their effective rent, wanted to move back into their dwellings after the refurbishment due to the considerable improvement of living standards and the very Source: D. Slawski, Essen

positive image of the area due to the solar refurbishment. The company is noticing a high demand for these dwellings today.

The projected was awarded as “Solarkraftwerk im Haus 2002”.

The survey prepared for this paper empirically demonstrates that PV performance contracting has had an increasingly significant impact on solar market development. While only 6.75 kW of PV were installed through performance contracts in 2000, that number grew to 3.36 MW in 2003, or 10.5% of the US grid-connected installations. When considered within the historical context of the performance contracting market, this result is surprising given the lack of PV performance contracts before 2000. It is possible that this trend reflects a transient policy experiment. On the other hand, it may be indicative of a change in PV’s position in the energy services market. Facilities that place value on PV’s environmental and service-oriented benefits are turning to performance contracting to overcome installation hurdles. Performance contracting allows facilities to install PV at no up-front capital cost and to blend PV’s payback term down to acceptable levels. With the Federal government pioneering the model and other sectors adopting it, PV performance contracting is poised for continued development. If stakeholders in both industry and government work to resolve the current barriers, PV performance contracting may evolve into a reliable tool for deploying PV across the institutional and commercial sectors.

References

Anderson, R. R., Sullivan, J. B., Dunkerly, J. C., 1999. Briefing Paper on Energy Service Companies with Directory of Active Companies (rev. ed). World Energy Efficiency Association, Washington, DC.

Brown, D. R., Dirks, J. A., Hunt, D. M., 2000. Economic Energy Savings Potential in Federal Buildings. Pacific Northwest National Laboratory, Richland, Washington.

Byrne, J., Agbemabiese, L., Kliesch, J., Wang, Y. D, Nigro, R., 1999. CO2 and SO2 Mitigation Potential of Cost-Effective Photovoltaic Applications in the U. S. Public Buildings Sector. Center for Energy & Environmental Policy, Newark, DE.

Byrne, J., Kurdgelashvili, L., Poponi, D., Barnett, A., 2004. The potential of solar electric power for meeting future US energy needs: a comparison of projections of solar electric energy generation and Arctic National Wildlife Refuge oil production. Energy Policy 24(2), 289-297.

Byrne, J., Letendre, S., Agbemabiese, L., Redlin, D., Nigro, R., 1997. Commercial Building Integrated Photovoltaics: Market and Policy Implications. Proceedings of the 26th IEEE Photovoltaic Specialists Conference, Anaheim, CA, pp. 1301-1304.

Byrne, J, Letendre, S., Aitken, D.,1998. Photovoltaics as an Energy Services Technology: A Case Study of PV Sited at the Union of Concerned Scientists Headquarters. Proceedings of the American Solar Energy Society Solar 98 Conference, Albuquerque, NM: 231-237.

Clinton, William J., 1999. Executive Order 13123. Office of the President of the Untied States of America, Washington, D. C. Accessible on the worldwide web at: www. epa. gov/fedsite/eo13123.htm.

Dayton, D. S., Goldman, C., Pickle, S., 1998. The Energy Services Company (ESCO) Industry: Analysis of Industry and Market Trends. Proceedings of the ACEEE 1998 Summer Study on Energy Efficiency in Buildings, Pacific Grove, CA.

Department of Energy, Office of Energy Efficiency and Renewable Energy (DOE/EERE), 2003. CHP and PV Increase Power Reliability at Twentynine Palms MAGtFtC. Accessible on the worldwide web at:

www. ornl. gov/sci/femp/pdfs/fs-5903_29palms_usmc. pdf.

Dominick, J., 2003, telephone interviews, December.

Eckhart, M. T., 1999. Financing Solar Energy in the U. S. (Scoping Paper). Renewable Energy Policy Project, Washington, DC.

Federal Energy Management Program (FEMP), 2004a. DOE Super ESPC Delivery Order Guidelines, v3.04. US DOE, Office of Energy Efficiency and Renewable Energy, Washington, D. C.

Federal Energy Management Program (FEMP), 2004b. FEMP Awaiting Reinstatement of ESPC Authority. Accessible on the worldwide web at: www. eere. energy. gov/femp.

Federal Energy Management Program (FEMP), 2004c. Super ESPC Awarded Delivery Orders. Accessible on the worldwide web at:

www. eere. energy. gov/femp/financing/superespcs_awardedcontracts. cfm.

Federal Energy Management Program (FEMP), 2004d. Qualified ESCOs. Accessible on the worldwide web at: http://www. eere. energy. gov/femp/.

Federal Energy Management Program (FEMP), 2003a. Navy Uses Super ESPC to Make Photovoltaic Energy Pay. FEMP Focus Mar/Apr 2003.

Federal Energy Management Program (FEMP), 2003b. Technology-Specific Super ESPCs. Accessible on the worldwide web at: www. eere. energy. gov/femp/.

Federal Energy Management Program (FEMP), 2002. Federal Energy Management Program Year in Review: 2002. US Department of Energy, Office of Energy Efficiency and Renewable Energy, Washington, D. C.

Goldman, C. A., Osborn, J. G., Hopper, N. C., Singer, T. E., 2002. Market Trends in the U. S. ESCO Industry: Results from the NaESCO Database Project. Lawrence Berkeley National Laboratory, Berkeley, CA.

Hall, Chuck, 2003. Performance Contracting. Presentation at the Rebuild America Financing Energy-Efficiency Improvements Workshop, Arlington, VA.

Hughes, P. J., Shonder, J. A., Sharp, T., Madgett, M., 2003. Evaluation of Federal Energy Savings Performance Contracting — Methodology for Comparing Process and Costs of ESPC and Appropriations-Funded Energy Projects. Oak Ridge National Laboratory, Oak Ridge, TN.

Johnson Controls, Inc., 2003. Johnson Controls Wins $51 Million Energy, Facility System Upgrade Project at Twentynine Palms. Accessible on the worldwide web at: http://www. jci. com/CorpPR/Releases/cg/release599.asp.

Lovins, A. B., and Lovins, L. H., 1982. Brittle Power: Energy Strategy for National Security. Brick House Publishing, Andover, MA.

Macintosh, B., 2003, telephone interview, January 10.

Maycock, P., 2004, telephone interview, March 29.

Neeley, B., 2003. Financing Distributed Generation and Combined Heat and Power Plant Projects. Presentation at the Distributed Generation and Combined Heat and Power Workshop, Newport Beach, CA.

Oak Ridge National Laboratory (ORNL), 2003. Practical Guide to Savings and Payments in Super ESPC Delivery Orders. Federal Energy Management Program, US Department of Energy, Office of Energy Efficiency and Renewable Energy, Washington, D. C.

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Rufo, Michael W., 2001. Performance Contracting and Energy Efficiency Services in the Nonresidential Market — Market Status and Implications for Public Purpose Interventions. State of Wisconsin Department of Administration, Division of Energy, Madison, WI.

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Strajnic, T., 2004, telephone interview, November 12.

Stronberg, J., Singh, V.,1998. Government Procurement to Expand PV Markets. Expanding Markets for Photovoltaics. Renewable Energy Policy Project, Washington, D. C.

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Utility vehicles in Brazilian University campi are typically powered by small diesel tractors, to which small trailers are attached. These vehicles, called “Tobattas”, have a widespread use on campus to carry goods, furniture and trash. At Universidade Federal de Santa Catarina they are also used to displace organic waste on a compost project carried out by the Department of Rural Engineering. The nature of the work performed by Tobattas at UFSC is such that their diesel engines are kept running many hours every day, but the total distance they cover daily is typically under 20 km. Diesel engines are left running idle while workers load and unload their Tobattas, and electric vehicles, powered by batteries assisted by PV modules, seem perfect to do this job. Noisy and smelly Diesel-engine Tobattas run around campus all day long, sharing pedestrian lanes with students and staff. In this context, LABSOLAR and the University’s Campus Services Unit retrofitted a golf-cart-type electric vehicle (EV) with PV modules to reduce noise and air pollution, to further showcase PV to the University community, and to study the behaviour of such a vehicle. Preliminary calculations revealed that the available area for PV modules on the EV’s rooftop would represent a negligible contribution to the total energy fed to the batteries (the EV would actually have to sit for over two days under the sun to fully charge the battery bank!). However, the voltage support rendered by the PV modules turned out to be a significant advantage for this particular application, especially when the battery bank state of charge is low, considerably extending the EV’s mileage. Figure 9 shows the original, Diesel-powered Tobatta and the PV-assisted EV.

For test purposes the ozonizer constructed at the Institute of Electrical Engineering and Electrotechnologies has been used. The discharge element is the dielectric in the form of the tube made of boron-siliceous glass, the inside walls of which are covered with the aluminum layer that is high-voltage electrode. High voltage is supplied by steel-brush electrode adherent to deposited aluminum layer and this is the active part of the discharge unit. Dielectric tube is centrally placed inside the tube made of acid resistant steel which is low-voltage earthed electrode. During ozonizer’s operation between the walls of low-voltage electrode circulating liquid that removes heat generated in the process of the ozone synthesis will circulate. Ozonized water has been used as the cooling liquid.

The structure as well as geometrical dimension are presented below.

Geometrical dimensions, parameters of the discharge slot and dielectric barrier are presented below:

inside diameter of the discharge unit — 70mm, outside diameter of the discharge unit — 74mm, thickness of the dielectric — 2mm,

length of the discharge element — 1100mm,

length of the discharge slot — 4mm

capacity of the dielectric capacity of the discharge slot resultant capacity of the discharge element

Apart from the ozonizer, the system comprises the container in which the process of ozonization is generated and air and water pumps. (Fig. 3).

Practical application revealed that the described system does not require reactive power compensation because the capacity character of the discharge elements has been compensated by supplying transformer.

2. Conclusions

The installations for swimming pool water ozonization are particularly assigned for solar energy supply since they operate in spring and summer season and do not require continuous operation. Swimming pools are used in the period of good weather therefore applied photovoltaic system does not require auxiliary elements for the accumulation of energy. At periodic operation of the ozonizer the demand for energy can be completely satisfied by photovoltaic system.

Nowadays, chlorine is mostly used for water treatment however it is harmful for human beings. The application of the ozone will allow for the elimination of the chlorine and thus improve swimming comfort.

Ozone generators are the receivers of specific features, the discharges inside introduce strong voltage and current distortions and thus the quality of energy is worse. Described stand alone system is not connected to the power network and does not have negative impact on its operation.

At present, photovoltaic system supplying water ozonizing installation is being constructed in the laboratories of the Institute of Electrical Engineering and Electrotechnologies. However, the investigations on real objects will be carried out in order to asses advisability of such systems.

1.1 Forced convection cooling

1.1.1 System description

The cross-sectional view of immersion system of forced convection cooling is shown in Fig.1. The fluid enters the vessel with the temperature T and leaves at the temperature To. Heat from solar cells is transferred to the liquids through convection and conduction. The system is tilted at an angle equal to the local latitude (39.13°).

1.1.2 Thermal model

The thermal network of forced convection cooling system is shown in Fig.2.

The heat balance equations are now presented as followed:

For transparent cover,

G + h (T — T) + hf(Tf — T) + h (T — T) = 0 (1)

g ag a g fg f g eg c g

Where Gg is the total solar energy absorbed by transparent cover

Gg = Gd ~Pg )«g

The heat transfer coefficient from the top cover to the surroundings is calculated using the relation by Duffie[11],

hag = hw + hgs

hw = 2.8 + 3.0v

— t4) Tg — Ta

The relationship between sky temperature and local air temperature is

Ts = 273.15 + 0.0552(Ta -273.15)15

The radiation heat transfer coefficient between solar cells and top cover can be written as

For liquid,

AgGf + Agh, (Tg — Tf) + 2Achcf (T-Tf) = qu + T — Ta)

where

Gf = Gaf (1 — Pg )(1 -«g)

qu = mc(T0 — Ti)

For solar cells,

G + 2hc(Tf -T) + h (T — T) = E

c fc f c gc g c

where Gc is the total solar energy absorbed by solar cells,

Gc = G^c(1 — Pg)(1 — ag)(1 — pf )(1 — af)

The conversion efficiency of the PV ^ is a function of its temperature calculated by the relation [12]:

E = Gcqc = 0.125Gc [1 — 0.004(Tc — 293)]

The convection heat transfer coefficient hgf and hfc are calculated using the relation given by Bejan [13]. Relevant parameters of system have been given in Table 1. The silicone oil properties are obtained from [14].

The model is used to simulate solar cell temperature (Tc), transparent cover temperature (Tg) and outlet fluid temperature (To) with different operational parameters.

Fig.4. shows three various components temperatures as a function of irradiance at fixed mass flow rate and fixed inlet liquid temperature. The temperature of solar cells is increased from 301 to 374K when irradiance is increased from 1000 to 9000 W/m2K. In fact, to maintain low temperature of solar cells at high irradiance, system parameters need change correspondingly. Fig.5. represents the variation of three components temperature as a function of inlet fluid temperature. It is obvious that solar cells temperature increases with the increase of inlet temperature. In practical operation, it is important to understand the result of various inlet fluid temperatures because it is difficult to maintain fixed inlet temperature. The effect of mass flow rate on system temperatures is shown in Fig.6. Because the fluid is in laminar flow and irradiance is not too high, the temperatures of three components vary little with the increase of mass flow rate.

1.2 Free convection cooling

1.2.1 System description

The configuration of free convection cooling is similar to forced convection cooling system. There is no need for additional pump for fluid flow because free convection is caused by fluid motion due to density differences. It can decrease system cost. The vessel is filled with silicone oil and the inlet valve and the outlet valve are closed.

1.2.2 Thermal model

Heat from solar cells is transferred to the vessel walls by silicone oil through convection and conduction. Mathematical model of free convection resembles model of force convection. Equation (9) is replaced by equation (15) and equation (8) and (11) are cancelled.

For liquid,

^g fg g

2.2.2 Results

Fig.7 and Fig.8 illustrate the temperature variation of three components as a function of ambient temperature and irradiance. The solar cells temperature in free convection cooling

system is higher than in force convection at the same irradiance. The temperature of solar cells increases with the increase of ambient temperature.

To decrease the temperature of fluid and solar cells, natural convection system should be high heat flux between the vessel walls and surroundings. That means t o increase heat transfer area and heat transfer coefficient between them. Vessel walls should be high thermal conductivity and thin thickness. Adding fins on vessel walls can extend available heat transfer surface area.

On the basis of a number of literature sources examined, it may be inferred that lack of knowledge and lack of confidence regarding RES are the most significant factors hindering the deployment of RES applications in buildings (Coninck, R. De, et al, 2004). Higher costs and burdensome administration or complex regulatory structure appear to be the next two most important constraints. The problem of ownership vs. beneficiary of investment appears to be of less importance, and does not pose a constraint as a general rule. The importance of political support and coherent policy framework is emphasised clearly in the European Commission White Paper (EC, 1997). A questionnaire was sent out to a limited number of key persons (mainly policy makers) in five member states in order to check the constraints found in literature. The results of the questionnaire confirm the findings of the literature study, but more or less inverses the order of major constraints. According to the 43 respondents, the major barrier is high investments required for renewable energy technologies (Coninck, R. De, et al, 2004). The lack of knowledge and a general inertia for changes are situated in second place. There was no rating for policy as a barrier, but the policy makers are clearly identified as the market actor representing the biggest bottleneck for the penetration of rEs in buildings.

With high investments as a major barrier, it was only logical that the respondents of the questionnaire rated fiscal incentives at purchase as the most appropriate instrument. But financial support only is not enough to make the difference: the introduction of energy performance regulations was seen as the second most promising tool to support the penetration of RES in buildings. The respondents clearly mentioned that to tackle all the barriers, action is necessary in different domains, which explains the need for feed-in regulations, education and training, political ambition, subsidy schemes, etc. With respect to the energy performance regulation it can be concluded that such a regulation on itself is regarded as a very promising way to introduce RES in buildings. There is no consensus amongst the respondents as to the necessity, the choice nor the way of implementing specific RES-stimulating measures in an EPR. Obligations to apply one or another technique will never be welcomed, and it should always be clear that RES should not be a goal in itself. The final goal is to improve CO2 reduction, and renewables are a mean to achieve this. Finally, not only can the mitigation of barriers be facilitated by political will but may in fact require political will in order for the necessary changes to be realised. The lack of political support can therefore be central to the existence of constraints.

Systems of building control in member states may cause constraints for use of RES techniques in buildings in case administrative barriers are too high (Sheridan, L., Foster, M. et al, 2004). In Belgium, France and the Netherlands, installations of small PV panels and solar thermal collectors are exempted from requirements for permits, or subject to reduced permit requirements. Permits are required in Denmark. Building regulations in England and Wales do not make direct mention of such installations, but building- integrated panels and solar thermal systems are subject to building control; planning
guidance now mentions PVs, and any equipment that affects the appearance of buildings is subject to planning controls.

Johann Gerdenitsch, department of environmental planning and Solar Appointee of the city of Fuerth

Introduction

With the implementation of the Atzenhof Solar Mountain project, the city of Fuerth took another important step on its way to becoming a solar city.

The utilization of waste site gas and the production of solar electricity reduces CO2 by an average of 1200t per year which is an effective contribution to cli­mate protection.

Alone the investment volume of approximately 4.7 mill.€ reveals, next to the enviromental, the economical dimension of the project. The concept of invest­ment by citizens and the high rate of investment to raise the necessary share­holder’s capital, clearly proves that citizens are willing to invest in concrete climate protection projects and thus, also the effectiveness of the Renewable Energy Law.

The example set by the municipality, which participated in the financing with

500.0

€, is further proof that partnership projects (municipality and citizens) find successful application in matters of the sustainability principle.

Location and coverage of the PV-installation

The location of the PV-facility is a 1.7 ha area at the south slope of the Atzenhof waste dis­posal site; the south orientation and the raised position of the installation should guarantee the highest possible energy production. The total area is divided in 2 partial areas by a ser­vice road.