Category Archives: SonSolar

In conclusion

In conclusion it is fair to say that the Pyreheliophero and all the work leading up to it were remarkable achievements for Father Himalaya’s time, truly deserving their dissemination among the solar energy scientists of today and even among the general public interested in the History of Science and Technology.

Very high concentration of solar radiation on a continuous basis was achieved by a play of clever optics and simple mechanisms, in particular in the case of the Pirheliophero. Quite
likely it produced in a sustainable manner the highest temperature ever with a solar device, a World Record for the day. Even today it is not easy to obtain higher temperatures and the limitations in terms of the knowledge of optics, materials, sensors, etc. are quite different from those at the turn of the 19th century.

For the record it is important to point out that Father Himalaya was not always correct in his interpretations or in his stated goals. That is quite understandable when only later day science could prove him wrong. However in other instances, when even scientists of his day might have been able to correct him, he did not know better. In that case a possible excuse is that he had no way to encompass in depth the very wide range of knowledge that he needed in order not to make those specific wrong statements or claims, in particular given his lack of a high level formal training in the basic sciences, as referred. That should not prevent us from admiring his powerful and creative mind, brilliantly complemented by his cunning practical eye, to translate ideas into useful devices.

For instance, after his forays into Solar Energy, Father Himalaya moved on to other topics which, as commented upon in the Introduction, included among many other remarkable things, explosives and rotary engines.

After St. Louis he continued to work and travel all over the World, and got wide recognition, especially from his fellow country men and in particular in the region he came from, Minho, in the North of Portugal. Throughout the rest of his life he kept right on a collision course with many of the established views of the day, in such diverse areas as religion, politics, agriculture, medicine, industry, social development, ecology, etc., to a degree which would make him feel quite at home in today’s World. Perhaps that really constitutes the best summary of his persona: a man 100 years ahead of its time. He died in December, 21st, 1933.

Final note: an extended version of this paper is being published in 2004 in Annals of Solar Energy, chapter XX.


[1]-Jacinto Rodrigues — "A Conspiragao Solar do Padre Himalaya"-Edigao Cooperativa de Actividades Artisticas, 1999 (ISBN-972-9089-44-2)

[2] A. Mouchot "La Chaleur Solaire et ses applications industrielles" Paris Gauthier Villar, Imprimeur Libraire, 1869

[3] Louis de Royaumont "Conquete du Soleil" Ed. Marpon et Flammarion (1880-86)

[4] Charles Metelier "La conquete paciphique de l’Afrique par le soleil", Paris, Ed. 1890

[5] Journal « Seroes » , April 1901 ( on Calver’s system in Tucson, Arizona)

[6] Journal « Gazeta Ilustrada », 1901 (drawings with Aubrey Eneas truncated cone)

[7] Journal « Seroes » June 1901, ( Solar engine by Aubrey Eneas, Pasadena, California)

[8] Aden B. Meinel, Marjorie P. Meinel « Apllied Solar Energy, an Introduction » Addison Wesley Publishing Company, 1976, Second Printing, January 1977

[9] Patent 292 360, 7 September 1899, INPI, Paris

[10] Patent 293.512 October 20, 1899, INPI, Paris

[11] Patent 307.699, January 31, 1901, INPI, Paris

[12] Patent 3746, Livro 4°, fl.151, August31, 1901, Rep. Propriedade Industrial, Lisboa

[13] Patent 797 891, August 22 1905, National Archives Washington D. C, U. S.A.

[14] Private communication to Prof. Jacinto Rodrigues, made by Prof. Joao Gabriel da Silva (Universidade de Coimbra) and integrated in [1].

[15] Adolphe Demy ’’Exposition Universelle”-pp. 709-711 Bibliotheque de St. Genevieve, 1904, Paris

[16] “History of the Louisiana Purchase Exhibition” , pp.281, Universal Exposition Publishing Company, 1905, St. Louis, U. S.A.

[17] J. W. Buel, Editor, “Louisiana and the Fair” pp.3128, World’s Progress Publishing Co. 1904­1905,

[18] “Sunday Magazine St. Louis Post Dispatch” , July 10, 1904

[19] “St. Louis Republic” October 2, 1904

[20] “Western Watchman” January 5th, 1905

[21] “New York Times” and “ New York Herald” , March 12th, 1905

[22] “Scientific American” October 1904

[23] — W. T. Welford, R. Winston “ The Optics of Non Imaging Concentrators” , 1978, Academic


The author wishes to thank in the first place, Prof. Jacinto Rodrigues for all the conversations and collaboration received, in particular for the copies of the patents and other documents which were thus possible and easy to consult. Secondly the author wishes to thank Rui Rodrigues from INETI who helped with handling of all photographs and drawings. The author further wishes to thank Prof. J. J. Delgado Domingos from IST for the copies of the documents in his possession, an indispensable complement of the ones obtained form Prof. Jacinto Rodrigues and Mss. Maria Abreu e Lima from Cooperativa de Actividades Artisticas and Mr. Humberto Nelson from Pagella, for the photographs made directly available.

Special thanks to Dr. Cesare Silvi, Vice president of ISES Italia and immediate past President of ISES International, for the efforts he his making to promote a thorough look at the history of Solar Energy and the encouragement the author got from him to undertake the task of writing this paper.

Solar education combining art, history, science and. technology at archaeological sites in Italy

Cesare Silvi, ISES ITALIA*, csilvi@indra. com Patricia Ferro, ISES ITALIA*, criferro@tiscali. it

Tiziana Ceccarini, Educational Section — State Superintendence of Archaeological Monuments in Rome*, tiziana. ceccaririi@archeorm. arti. beriiculturalUt


Italy’s landscape is dotted with historical towns and archaeological sites. The integration of renewable energy technology in the Italian built environment and landscape and its aesthetic impact is raising various concerns, especially due to the rapidly growing deployment of wind and other solar energy systems.

On these aspects and, more in general on solar energy, ISES ITALIA, in cooperation with and support of the Educational Section of the State Superintendence of Archaeological Monuments in Rome, is promoting solar energy education combining art, history, science and technology at archaeological sites.

This concept started to emerge in 1992 and became a program for schoolchildren in the year 2000 as a follow up to two solar spectrum art exhibitions, named “SOS — Secrets of the Sun: Millennial Meditations" and “New Light on Rome", held at the Trajan’s Markets, one of the most spectacular ancient monuments in the heart of Imperial Rome, and other monuments.

The success of the exhibitions, which attracted thousands of visitors, and the fruitful cooperation with the authorities responsible for the monuments, in particular the Archaeological Superintendence, the City of Rome, and the State Superintendence of Archaeological Monuments in Rome, lead to the exploration of the possibility to integrate existing educational programs for schoolchildren on history and archaeology with energy topics and the related environmental issues.

In the year 2000, ISES ITALIA and the State Superintendence of Archaeological Monuments in Rome started the project "Solar Energy by studying Ancient Architecture", and have since held solar educational laboratories at archaeological sites involving more than 1000 students, dozens of teachers and five archaeologists. Among the educational tools used was the exhibition “Arte e Tecnologie Solarf’ (Solar Art and Solar Technologies). The addressed topics at the laboratories range from the use of renewable energy in past civilisations and in ancient buildings, as well as prospects for the use of solar energy in the future. In this paper details are provided about "Solar Energy by studying Ancient Architecture" at two

archaeological monumental complexes in Rome: Villa dei Quintili, of the I-II centuries A. D., and Diocletian Baths of III — IV centuries A. D.

The views expressed in this paper are solely those of the authors and should not be ascribed to ISES ITALIA or to the State Superintendence of Archaeological Monuments in Rome

Examples for mathematical problems on solar thermal energy

This contribution provides in the following the short cuts of some examples of mathematical problems concerning future energy issues. The problems presented here deal with the topic ‘Solar Thermal Energy’. They are suitable for lessons in secondary schools. Our presentation is focused on the basic structure of the problems, in order to give an impression of the didactical concept and the general principles.

1.1 Example 1

> This problem can be treated in lessons to the topic of percent calculation and the rule of three. It requires the understanding and usage of data representations.

In private households the required warm water can be partly heated up by solar thermal collectors. They convert the solar radiation energy in thermal energy. It helps us to decrease the usage of fossil fuels, which lead to environmental problems.

Hot process water needs preferably to have in private households about 45°-55°C. In our region, the usable thermal energy from the sun is not sufficient to reach this temperature permanently, because of the seasonal behaviour. Thus, an input of supplementary energy is necessary.

Figure 1: A solar thermal energy plant (DGS)


The following table shows how much of the needed energy for heating up water to a temperature of 45°C in private households can be covered by solar thermal energy, respectively how much supplementary energy is needed.


Energy Coverage in %

Month March (1) to February (12)

Figure 2: Usable Solar Energy and Additional Energy

How many percents of the needed thermal energy for one year can be covered by solar thermal energy?

Energy is measured by the unit kWh.

An average household in Germany consumes nearly 16.000 kWh thermal energy per year.

1 l fossil oil provides approximately 10 kWh thermal energy. The combustion of 1 l oil produces nearly 68 l CO2.___________________________________________________


Assume in the following, that the used water is heated up to a temperature of 45°.

b) How many kWh may be covered in one year by solar thermal energy?

c) How many litres of oil have to be bought for the needed supplementary thermal energy for one year for a private household?

d) How many litres oil would be needed without solar thermal energy?

e) How many litres CO2 could be saved by an average household in Germany during one year if using a Solar Collectors?

1.2 Example 2

> This problem deals with linear functions. The understanding and usage of graphical representations is performed.

Energy is measured by the unit kWh.

An average household in Germany consumes nearly 16.000 kWh thermal energy per year.

1 l fossil oil provides approximately 10 kWh thermal energy. The combustion of 1 l oil produces nearly 68 l CO2.________________________________

Figure 3: Dimensioning Diagram


The diagram in figure 3 provides data for planning a solar collector system for a private household. It shows the dependence of the needed collector area on the part of Germany where the house is situated, on the number of persons living in the respective household, on the desired amount of warm water per day and person, as well as the desired coverage of the needed thermal energy by solar thermal energy (in per cents).

Example: In a household in middle Germany with 4 persons and a consumption of 50 l warm water per day for each one, follows for a reservoir of 300 l and an energy coverage of 50%, that a collector area of 4 m[46] is needed.

a) What would be the needed collector area for the household you are living in? Which assumptions do you need to make first? What would be the minimal possible collector area, what the maximal one?

b) On a house in southern Germany there is installed a collector area of 6 tT that provides 50% of the produced thermal energy. How many persons could be supplied in this household with warm water?

c) Describe by the term of a linear function the dependence of the storage capacity on the number of persons in a private household. Assume first a consumption of 50 l warm water per day and person, and second a consumption of 30 l. Compare the two function terms regarding also their graphical representation.

d) Show in a graphical representation the dependence of the collector area on a chosen storage capacity, assuming a thermal energy coverage of 50% for a house in middle Germany.

1.3 Example 3

> This problem can be integrated in lessons to quadratic parabola and uses their focus property.2

Direct solar insolation may be concentrated in a focus by means of parabolic sun collectors. These use the focus property of quadratic parabola.

Special sun collectors are figures with rotation symmetry, they evolve by rotation of a quadratic parabola. Their inner surface is covered with a reflective mirror surface, that is why they are named parabolic mirrors.

Sun beams may be assumed as being parallel. Thus, if they fall on such a collector, parallel to its rotation axis, the beams are reflected that way, that they all cross the focus of the parabola. The thermal energy insolation may be focused this way in one point.

The temperature of a heating medium, which is lead through this point, becomes very high, relatively to the environment. This is used for heating purposes, but also for the production of electric energy.___________________________________________________________



Figure 4: Parabolic Sun Collectors (DLR)

A parabolic mirror was constructed by rotation of the parabola y = — x2. Determine its focal length (x and y are measured in meter).

b) A parabolic mirror has a focal length of 10 m. Which quadratic parabola was used for its construction?

c) Has the parabolic mirror with y = 0,05×2 a greater or a smaller focal length than that one in b)?

d) A parabolic mirror shall be constructed with a width of 2,40 m and a focal length of 1,25 m. How great is its arch, i. e. how much does the vertex lay deeper than the border?


Figure 5: EuroDish System (DLR Almeria Spain)

In figure 5 you see a parabolic mirror, the EuroDish with a diameter of 8,5 m. Determine out of the figure approximately, neglecting errors resulting from projection sight, its focal length and the describing quadratic parabola.

Other focussing sun collectors are figures with length-symmetry, they evolve by shifting a quadratic parabola along one axis direction. They are named parabolic trough solar collectors.

Figure 6: Parabolic Trough Solar Collectors


f) The underlying function of a parabolic trough solar collector is given by y = 0,35×2 (1 unit = 1 m). Where has the heating pipe to be installed?

The Structure

Fig. 1 The links and main collaborators of the Centre for Sustainable Development

The Center for Sustainable Development, part of the Transilvania University of Brasov, is linked with the local and regional institutions in charge with the development and/or implementation of different concrete aspects of the Sustainable Energy and collaborates with similar European structures, Fig. 1.

When initially launched, the Centre for Sustainable Development in Brasov had already have contacts and joint projects with successful European institutions that acted not only as models but also as active supporters in defining its aims and the strategy. Five of them, presented below, are the one who contributed extensively:

The Julich Centre in the FH Aachen in Germany is involved worldwide in applied research projects and provides education at undergraduate and M. Sc. level about subjects focusing on solar energy conversion to heat and electricity, on the passive use of the solar energy and the use of biomass.

The Energy Centre of the Netherlands is an European leader in the research of the renewable energy systems, mainly in developing the state of art (silicon based) and the new, non-silicon based PV cells, in wind energy and in passive solar design.

The Delft Institute for Sustainable Energy is a major research institute in the Delft University of Technology and provides high level research and education programs in solar PVs, in wind energy turbines, hydrogen technology and photo-catalytic processes and in sustainable industrial processes.

The Technological Research Centre of Iraklion, Crete, Greece hosts an open air laboratory where practical solutions for implementing RES are initiated, tested and then delivered to the large scale producers.

The University of Zaragoza, hosts, in the Faculty of Mechanics a department activating in passive solar design applied to urbanism projects and in solar to thermal energy conversion.

Now, there are more international partners (high level education institutions, companies, training institutions, and agencies) with which the Centre collaborates in promoting and supporting activities orientated on products’ research, design and development.

At national and regional level the links are involving institutions that are able to identify, at community level, the real needs and to promote practical solutions.

The National Centre for Sustainable Development elaborated, with support from UNDP, the first National Strategy for Sustainable Development, involving more than 200 government officials, politicians, business and trade union leaders, academics and representatives of the civil society. The Romanian Government officially adopted the Strategy, with just a few amendments.

The Brasov County Council represents the regional authority and as collaborator of most of the project of the Centre has an active contribution at the decision and dissemination level about the energy efficiency components.

The Brasov Association for Energy Management, lately founded as result of a SAVE project, is so far active mainly in projects related to energy saving and energy efficiency and is a valuable partner in providing information and links with the regional companies and institutions.

The links with the economic, social, education and training bodies is continuous and expands according to the increasing offer of the Centre for Sustainable Development.

Faculty of Construction

The Brasov Centre for Sustainable Development

Faculty of Electrical Engineering

In order to be able to answer to the rather various needs and opportunities, the Centre is internally organized in laboratories, joining groups from five faculties; this gives the possibility of an interdisciplinary approach of the subjects and allows the product — orientated research and training, Fig. 2.

Fig. 2. The internal structure of the Centre for Sustainable Development

Five years of experiences

Five ESES years are now completed: 1999/2000, 2000/1, 2001/2, 2002/3, 2003/4. Class size has grown from 7 to 26. We have 90 qualified applications for 2004/5 and expect a full group of 26 students to start on 18August 2004.

In spite of its name, about half of the students have come from countries outside Europe. Previous ESES students have come from 23 countries in 4 continents: China, Dominican Republic, Eritrea, Etiopia, Finland, France, Germany, Hungary, India, Indonesia, Italy, Jamaica, Mexico, Nepal, Netherlands, Nigeria, Pakistan, Spain, Sweden, Syria, Tanzania, Turkey, and USA. Thus, the program attracts as many students from countries outside Europe as Europeans, especially from developing countries. The course language — English — isa problem for some students. Several students may have good grades in their previous exam, but lack ability to experiment, training in doing creative thinking, or both. Swedish winter weather and lack of sunshine are other obstacles. In spite of this, the majority of the students manage all tasks, and some do it really well.

From the start 1999, we have arranged with a special student room in SERC, equipped with a number of computers. Students have access to this room 24 hours per day, 7 days perweek. During normal working hours, they also have access to SERC’s Pleijel Library, with hundreds of reference books and many journals. The proximity between ESES students and SERC researchers is generally appreciated by both the staffand the students.

Most students like our choices of rather theoretical textbooks, but some complain about too much theory and too much physics. They may be partly right, but we try to convince them that education at master’s level is not the same thing as in-service training of plumbers or electrical technicians. We believe that experimental and computer experience is important, and ESES students agree — at least after some time experiencing both. Students with very little computer experience may encounter initial problems, but they improve quickly (especially when they learn that they can chat nightly with friends on the other side of the earth free of charge on their student computers). Some also take the optional TRNSYS unit, learning how to utilize this simulation program.

The most important experience for us so far is that most graduated ESES students have gotjobs in industries and research institutions, or have been admitted to graduate schools, in their home country or elsewhere.

The Sun Emulator: A Means for Achieving the. Widespread Acceptance of Solar Responsive Design

Norbert M. Lechner, Professor and Architect Auburn University

College of Architecture, Design, and Construction 119 Dudley Hall

Auburn, AL 36849-5315 USA

Tel 334-844-5378 Fax 334-844-5386

lechnnm@auburn. edu

Since buildings use more than a third of all energy, and since most of that energy is for heating, cooling and lighting, and since the sun has a great impact on each of these energy uses, solar responsive architecture is a key factor in addressing global warming, energy depletion and pollution. The problem is not what to do, but why aren’t we doing it. Some people assume that solar responsive design is too expensive, others believe it is too complicated, and still others believe it is not ready yet but will be in the future. How then can we convince the great majority of people that solar responsive design makes sense right now?

I have found that a conceptually clear heliodon, such as the one I developed, can be both very convincing and impelling. The Sun Emulator heliodon is so conceptually clear that within two minutes even young children understand solar geometry as related to buildings. After all, it is not only building professionals but also clients, and future clients (children today) that need to be convinced of the benefits and appropriateness of solar responsive design.

Experience has shown that the Sun Emulator can clearly and quickly convince people of the great benefits and importance of such things as street orientation, building orientation, window placement, shading devices, clerestories (instead of skylights), and tree placement. The Sun Emulator makes clear that many of these beneficial strategies have no cost associated with them, and that we are missing out on many opportunities because of lack of knowledge and conviction.

The benefits of solar responsive design depend on the proper use of solar geometry which can be quite complicated when expressed mathematically or graphically, but is easily understood with physical models used on a conceptually clear heliodon. The Sun Emulator is such a conceptually clear heliodon because the ground plane always remains horizontal, the lights move across the model just like the sun moves across a building, and because the solar window is clearly and continuously simulated. There are no other heliodons that are as conceptually clear as the one I have developed, and because the Sun Emulator is so engaging, it is easy to teach solar geometry to any audience.

As a result of 25 years of experience with the use of heliodons, the author
recommends that all schools of architecture or building, science museums, energy resource centers, and some professional offices obtain a conceptually clear heliodon such as the Sun Emulator in order to inform not only the professionals but also the general public.

1. Heliodons:


FIG. 1

This type of heliodon uses multiple lamps to simulate the daily and annual motion of the sun. For limited latitude adjustment the model table can be tilted a maximum of 10 degrees each way.

Many different heliodons exist and almost all utilize one light to simulate the sun. Since the three variables of latitude, time of year, and time of day determine sun angles, a heliodon must be adjustable for all three factors. Only a few heliodons exist where the model is fixed and the light moves along three axes to adjust for all variables. In most heliodons, however, the model is rotated about one, two, or three axes instead of only moving the light. The disadvantage of these types of heliodons is that they do not match our real world experience and therefore such heliodons are not “conceptually clear.” They are neither very convincing to the uninitiated nor do they effectively teach the basic pattern of solar geometry as related to a building.

FIG. 2


More than twenty years ago, the author built a heliodon with about 130 lights to simulate the sun every hour of the 21st day of all twelve months (Fig. 1). Electrical switches control for the variables of time of day and year. The model table was still tilted for the latitude adjustment. Although "conceptual clarity” was greatly improved, there are a number of problems with tilting the model. With too much of a tilt, some of the conceptual clarity was lost, some lights moved below the horizon, and, of course, the model had to be carefully glued together and fastened to the table to keep it from sliding. Recognizing the weakness of a tilting table, the author developed over the last ten years a heliodon where the model of the building and remains stationary on the table, while the light moves to simulate the sun’s travels across the sky (Fig. 2). Although Copernicus would be upset, this situation fits perfectly with out daily real-world experience, and thus it allows us to form a mental model of the solar geometry that can be used for the design of buildings. While some heliodons accomplish this same goal with the use of only one light to simulate the sun, it turns out better to use seven lights to simulate the sun at different times of the year.

The Sun Emulator simulates our real-world experience by keeping the building model Stationary and horizontal while the lights move to simulate the sun’s apparent motion across the sky.

Results and discussion

The results obtained with primary energy or energy-cost minimisation do not differ fundamentally, assuming the present power export tariff. In other words, it makes no sense with regard to energy and finances to run the rCHP with the unique goal of power genera­tion if there is no need for heating, since the electrical efficiency of rCHP is too low in comparison to larger power plants. This statement remains valid for systems with and without a thermal solar system. In the past, some complaints arose: the current bonus amount is claimed to be to low to ever reach break-even for a plant and should be increased. Simulation has shown that if the bonus is increased above the point where the sole export of electricity makes the system financially profitable (i. e. without heat use), then the environmental benefits of the rCHP vanish and the operation time of the solar thermal system drops dramatically. The rCHP is then operated continuously up to the point when the storage tank is full and the plant must be switched off for safety reasons. This threshold value depends upon the fuel price, power remuneration rate and the electrical efficiency of the rCHP.

As a conclusion, the power export bonus must be kept below this threshold. If this is not enough to make rCHP financially viable, then the government should offer investment subsidies (i. e. lending at a lower interest rate than the average bank rate). In any case, the incentive for a CHP plant has no influence on the decision to buy a solar thermal system or not.

If one wants to have rCHP and solar thermal systems working together, an easy solution is a seasonally dependent CHP bonus. This means that the bonus is set to zero during the period with high solar irradiation. During the space-heating period, the bonus is increased to a higher value than the constant value in order to compensate for the financial losses in the summer. Over a one-year period, the operator must end up with the same total for both bonus models. This paper specifically handles the case of the German official heating period (from September to the end of May).

The seasonally dependent bonus approach has been illustrated in Fig. 4. There, the bonus has been set above the threshold (in that case around 11 cents/kWh). In the event of a constant bonus, the solar yield of a cost-driven system drops by 60% in comparison to a system optimised for primary energy. If the bonus is only paid in the heating period, the solar yield of the cost-driven system falls only by 26%. At the same time, the operator does not suffers from any financial drawbacks since the total annual bonus is nearly the same.

In addition to better solar performance, the simulation results show that the primary energy consumption of the cost-led system is almost the same as that of a primary energy-led system (mostly thanks to the solar input). As a conclusion, a seasonally dependent bonus is not a tool to promote solar energy (the financial profit remains the same) but it prevents the displacement of solar systems by fossil-fuelled rCHP systems. It is advised to let the rCHP operator have the choice between the two bonus approaches. Thus, he can freely decide whether to purchase a solar thermal system or not.

A further case is a time-dependent remuneration model, where the grid operator varies the value of remuneration according to his needs for CHP power. Fig. 5 deals with that issue.

It has been assumed that the remuneration rate varies according to the price fluctuation at the Leipzig power exchange (LPX). Here again, the seasonally dependent bonus smoothes the displacement effect (from -43% to -19%). As a conclusion, the seasonally

dependent bonus model can partly redress the negative effect of time-variable remuneration on the solar yield.


The results of an investigation about the combination of solar thermal systems with rCHP in terms of energy and economy benefits have been summarised in this paper. The discussion is based on simulations of technical building services. The results gained show that under the current regulatory and institutional framework (that means that the bonus remains at current level), solar yields are not jeopardised by the CHP bonus concept. In the event, that the public grid relies more and more on rCHP power, there is a risk that solar systems are displaced by rCHP systems, which are commonly operated with fossil fuels.

A new concept that relies on a seasonally dependent bonus has been presented. Simulation results show that this concept can address the issue above.

Moreover, this study has shown the need for new intelligent control strategies for rCHP plants, that react to weather forecasts and heat and power load predictions and can consider the interaction between a building and the heat supply chain in order to optimise the yield of the plant in a such way that fossil fuel can be saved or energy cost are minimised.


This work was supported by the German Ministry of the Environment, Nature Conservation and Nuclear Safety (BMU) in the framework of the Future Investment Programme (ZIP) and the research project “Umweltauswirkungen, Rahmenbedingungen und Markt — potenziale des dezentralen Einsatzes stationarer Brennstoffzellen” (Environmental effects, boundary conditions and market potential of distributed stationary fuel cells). Other project partners are DLR Stuttgart, IFEU Heidelberg, Wuppertal Institut, Ruhr-Universitat Bochum and ZSW Baden-Wurttemberg. The report of this study has been published as a book ([Krewitt et al. 2004]).








(Winter) (Winter) (Winter) CHP bonus (cents/kWh)















200 c




Fig. 4: Thermal solar yield versus the rate of the CHP bonus in the case of a low-energy house. On the right-hand side, in comparison to a constant bonus of 12 cents/kWh througout the year, the CHP bonus has been set to zero during the summer and has been varied between 12 and 14 cents/kWh in the heating period. In this way, the performance of the solar thermal system could be improved and the total annual bonus remains almost unchanged.

Solar yield [kWh/a] or CHP bonus [EUR/a]


— 43%














primary energy led, energy cost led, constant energy cost led, seasonally constant bonus bonus dependent bonus


Fig. 5: Variation of solar yield, total annual CHP bonus and primary energy consumption in the case of time-dependent remuneration. In the case of seasonally dependent

— 19%










□ Solar yield [kWh/a] □ Total annual CHP bonus [EUR/a] □ Primary energy [kWh/a]

□ Solar yield with constant bonus

□ Solar yield with seasonally dependent bonus

□ Total annual CHP bonus



Подпись: Solar yield [kWh/a] or CHP bonus [EUR/a]

bonus, the CHP bonus has been set to 0 cents/kWh during the summer and to 7 cents/kWh for the remaining part of the year

BritischeBotschaft Environment Team, British Embassy Berlin: Cogeneration Law Receives


Cabinet Approval; Download at

http://www. britischebotschaft. de/en/embassy/environment/pdf/env- note_01-35.pdf (28.03.04); 2001

Bruch et al. 2003

Bruch, C., Krumbech, M., Mertikat, H.: HT-BZ zur Strom — und Warmeversorgung: Betriebserfahrungen mit Anlagen im RWE Brennstoffzellen-PaviNon, Essen; Tagungsband des OTTI Profiforum Brennstoffzellen; 6-8 Oktober 2003; Berlin; 2003

Cogen 99

Cogen Europe: An introduction to Micro-Cogeneration; Briefing 8; Download at

http://www. cogen. org/Downloadables/Publications/Briefing%20MicroCH P. pdf (25.03.04); 1999

Sicre 2004

Sicre, B.: Sustainable energy supply to very-low-energy buildings by means of CHP technologies and solar thermal energy; PhD thesis at the Chemnitz University of Technology; Fakultat fur Maschinenbau; In German; Chemnitz; 2004

Vetter u. Wittwer, 2002

Vetter, M., Wittwer, C.: Model-based development of control strategies for domestic fuel cell cogeneration plants; Proceedings of the French — German Fuel Cell Conference 2002; S. 1-6; Forbach-Saarbrucken; October 2002

Training Guides developed within the TREN — LdV Project

Laurentiu Fara1, Jim Hopwood2, Graham Spinks3, Anne Rennie3, Silvian Fara4, Dumitru Finta4, Andreas Karner5, Marc Timmer6, Sabina Scarpellini7, Tonia Damvakeraki8, Ionut


1National Agency for Renewable Energy, Splaiul Independentei 313, Bucharest 77206, Romania, Tel: +40 21 4119603, Fax: +40 21 4119962, anesr@nare. renem. Dub. ro 2The Institution of Mechanical Engineers, c/o ExxonMobil Chemical Ltd, Hythe, Southampton, SO45 3NP, UK, Tel: +44 2380 895109, Fax: +44 2380 895909, iim. hoDwood@exxonmobil. com

3Multimedia Design Studio, 2 New Road, St Ives, Cambs, PE27 5BG, UK, Tel: +44 1480 494515, Fax: +44 1480 460841, graham. spinks@mdsl. demon. co. uk, anne. rennie@multimd. demon. co. uk

4Institute of Research and Design for Automation, Calea Floreasca 16, Bucharest 72321,

Romania, Tel: +40 21 2302293, Fax: +40 21 2307063, sfara@ipa. ro

5KWI Architects Engineers Consultants, Burggasse 116, A-1070, Vienna, Austria,

Tel: +43 1 52520 200, Fax: +43 1 52520 266, ka@kwi. at

6EUFORES Brussels Office, c/o European Parliament, ASP 13G242, Rue Wierz, 60, B — 1047, Brussels, Tel: +32 2 284 6422, Fax: +32 2 284 9921, smantell@eufores. org 7CIRCE, CPS — Marla de Luna 3, E-50015, Zaragoza, Spain, Tel.:+34 976 761863,

Fax: +34 976 732078, sabina@posta. unizar. es

8Atlantis Consulting SA, 51 Polytechniou str, Zip 546, 25 Thessaloniki, Greece, Tel: +30 31 524 854, Fax: +30 31 552 265, damvakeraki@atlantisresearch. gr

“EnergyTraining4Europe — a toolbox of money saving ideas on renewable energy and energy efficiency” (TREN-LdV) is a two and a half years running project (November 2002 — April 2005). It is funded by the European Commission Leonardo da Vinci programme, being developed by IMechE (UK) — co-coordinator and MDSL (UK), NaRe (Romania), IPA SA (Romania), KWI (Austria), EUFORES (Luxembourg), CIRCE (Spain), ATLANTIS SA (Greece).

The project aims to create a package of interactive training and guidance material that will help managers and engineers in SMEs and Local Authorities to develop an energy management plan for the buildings for which they are responsible. The plan will facilitate compliance with EU legislation on energy-related environmental issues and will identify opportunities for business improvement through innovation.

The key feature of the project is that it is based on a demand led training approach. Users will be guided quickly to find the information they need at the time when they need it.

The package will include:

■ Summaries of EU and Romanian legislation relevant to energy users in buildings;

■ Links to relevant national legislation and to sources of funding for projects improvement;

■ A diagnosis tool which will enable the manager or engineer to quickly identify the most important legislative issues, energy saving opportunities and potential RES supply;

■ Detailed advice and training related to each of the issues and opportunities identified, including: assessment of compliance with legislation and best practice; methodologies for exploring opportunities for improvement; support in
the specification of RES equipment, systems and services; support in the specification and procurement of energy efficient products and services.

■ A set of case studies illustrating the potential improvements.

■ User’s support through easy step-by-step instructions and website feedback forms (FAQs, technical help desk and tutor support);

■ Mechanisms for internal and external evaluation aimed at permanent improvement and updating.

All the materials will be designed to be useful to managers and engineers in SMEs and LAs in both the EU, and NAS. To support the material there will be an electronic discussion board.

The material will be available in the following media: via Internet, on CD-ROM, as a handbook.

Solar artwork at the Trajan’s Markets: Secrets of the Sun: Millennial Meditations and New Light on Rome 2000 by Erskine P

The idea of combining art, history, science and technology to educate people on solar energy started to emerge within ISES ITALIA in 1992 and became a program for schoolchildren in the year 2000.

1.1 SOS — Secrets of the Sun — Millennial Meditations

During the preparatory work promoted by ISES for UNCED (U. N. Conference on Energy and Development), on March 21, 1992 — shortly before the Earth Summit in Rio and on the date of the spring solstice — Erskine’s solar art exhibition, "SOS — Secrets of the Sun — Millennial Meditations" opened at Trajan’s Markets in Rome: a unique event in a unique venue (Silvi, 1992).

The exhibition was organized through the joint efforts of the Italian Section of ISES, the artist, the City of Rome’s Culture Department, the Archaeological Superintendence, the City of Rome, with a $300,000 grant from the Frederick R. Weisman Art Foundation.

In the prestigious setting of Trajan’s Markets, one of the most spectacular architectural complexes in the heart of Imperial Rome, still standing above the ancient Roman forum after two thousand years, Erskine installed a computer-driven outdoor heliostat, four mirrors to reflect the white Sunlight on prismatic devices projecting the play of coloured spectrum light into a series of darkened rooms. The colours of the solar spectrum, projected on the ancient walls, marble fragments and other creations by Erskine produced an impressive symbiosis of art, history, science, technology, architecture, and archaeology.

Fig. 1 — The heliostat in the »SOS-Secrets of the Sun’1 exhibition installed at the centre of Trajan’s Markets in Rome, 1992, powered by photovoltaic modules visible in the foreground

The exhibition’s symbolic messages evoked not only the relationships existing between the sun and life on earth, between the beauties of nature and the

environmental threats caused by humans, but also those between the sun and the civilizations that preceded ours, as dramatically represented by the vestiges of Trajan’s Markets, and the civilizations we could build by

coming to a new understanding of the connections between human culture, scientific and technological progress, and the biosphere we inhabit.

Before this event, the Italian Section had always focused essentially on the technical and scientific aspects of solar energy. With the efforts put into staging the "SOS — Secrets of the Sun," the Section intended to underline the importance it attributed to the cultural factors that, in an era of great technological progress, might constitute a far more difficult obstacle on the path to a solar future. The huge heliostat and the other technologically sophisticated solar systems that Erskine was allowed to install in the ancient edifice of Trajan’s Markets were seen as a wake-up call to meditate on the great cultural challenges we would meet in attempting to achieve widespread use of solar technologies.

The installation of the high-tech heliostat and other devices on the archaeological remains of the Trajan’s Markets was possible at the end of a labyrinthine course and a controversial authorization process for the installations. From one side the authorities of the monument were concerned for the impact of the installation on the monument itself. On the other side the proposed solar art exhibition at the Trajan’s Markets was seen as a powerful cultural means to call people’s attention to solar energy. The proposal came when world concerns about the environment were highlighted in the international agenda with the organization of the Rio Earth Summit.

Aesthetics and art were only one part of Erskine’s work. By means of Sunlight, text, and sound, Secrets of the Sun attempted to address such diverse issues as: the interaction of the Sun with the Earth, solar energy radiation spectrum and its interaction with the architecture of the Trajan’s Markets, advanced solar technologies, human colour vision, global warming, ozone depletion, urban acid deposition, mass species extinction, pollution and noise from car traffic, preservation of cultural heritage and more.

Final Remarks

The German version of all problems we developed in this project, including extensive explanations, and their solutions can be downloaded at the following internet address: http://www. math-edu. de under the topic ‘Anwendungen’.

The collection of worked out problems should finally be edited as a special text book for mathematics school education. For this purpose, the acceptance and supporting promotion of experts as well as politicians and educators is very important.


[1] KMK-Beschluss vom 17.10.1980. Umwelt und Unterricht. In: Informationen zur politischen Bildung 219, 2. Quartal 1988, 39.

[2] National Curriculum Council. 1989. Mathematics Non-Statutory Guidance. York: National Curriculum Council.

[3] Hudson, Brian. 1995. Environmental issues in the secondary mathematics classroom. In: Zentralblatt fur Didaktik der Mathematik 27, 95/1, 13-18.

[4] FUhrer, L. 1997. Padagogik des Mathematikunterrichts. Braunschweig/Wiesbaden: Vieweg.

[5] Blum, W.; Torner, G. 1983. Didaktik der Analysis. Gottingen: Vandenhoeck & Ruprecht.

[6] Brinkmann, A. & Brinkmann, K. Moglichkeiten zur Integration des Themas Regenerative Energien in einen fachubergreifenden Mathematikunterricht. In: 12. Internationales Sonnenforum, July 05-07, 2000, Freiburg. Munchen: Solar Promotion GmbH.

[7] Brinkmann, A. & Brinkmann, K. 2000. Beispiele zur Einbindung des Themas

„Regenerative Energien" in einen fachubergreifenden Mathematikunterricht. Istron — Tagung „Mathematik und Realitat" in Hamburg, November 02-04, 2000.

[8] Brinkmann, A. & Brinkmann, K. 2000. Moglichkeiten zur Integration des Themas Regenerative Energien in einen fachubergreifenden Mathematikunterricht. Soltec — Solar Didactica in Hameln, October 28, 2000.

[9] Brinkmann, A. & Brinkmann, K. 2001. Aufgaben fur einen fachubergreifenden

Mathematikunterricht zum Thema Photovoltaische Solarenergie. Problems for Applied School Mathematics Concerning the Topic of Photovoltaic Solar Energy. In: OTTI Energie-Kolleg (ed.). 16. Symposium Photovoltaische Solarenergie, March 14­16, 2001 in Kloster Banz, Staffelstein. Regensburg: Ostbayerisches Technologie — Transfer-Instuitut (OTTI), 114-118, English Abstract 119.

[10] Brinkmann, A. & Brinkmann, K. Rationelle Energienutzung und Regenerative

Energien als Thema in einem fachubergreifenden Mathematikunterricht. To appear in: Schriftenreihe der ISTRON-Gruppe. Materialien fur einen realitatsbezogenen Mathematikunterricht.

[11] Brinkmann, A. & Brinkmann, K. Angewandte Mathematik zum Thema der

erneuerbaren Energien. Landesinstitut Mecklenburg-Vorpommern fur Schule und Ausbildung L. I.S. A., Padagogisches Regionalinstitut Neubrandenburg, May 17, 2001.

[12] Brinkmann, A. & Brinkmann, K. Solarenergie im Mathematikunterricht — Didaktische Konzeption und Aufgabenbeispiele. 3. Solar Didactica, Solar-Energy World Exhibition 2001, Patron: The Minister for Education and Research E. Bulmahn, in Berlin, June 10, 2001.

[13] Brinkmann, A. & Brinkmann, K. Future Energy Issues in the Secondary Mathematics Classroom. Proceedings of the 5th Panhellenic Conference with International Participation on Didactics of Mathematics and Informatics in Education. October 12­14, 2001 in Thessaloniki, Greece.

[14] Brinkmann, A. & Brinkmann, K. Elecrtric Vehicles as a Topic for Applied School Mathematics, EVS 18, The 18th International Electric, Fuel Cell and Hybrid Vehicle Symposium and Exhibition EVS 18 — The World’s Largest Event for Electric Vehicles — Proceedings. October 20-24, 2001 in Berlin, Germany.

[15] Brinkmann, A. & Brinkmann, K. Autofahren — Mit Mathematik effizient in die Zukunft. Istron-Tagung „Mathematik und Realitat" in Karlsruhe, November 08-10, 2001.

[16] Brinkmann, A. & Brinkmann, K. Mit Mathematik in eine sonnige Zukunft — Solardidaktik fur einen fachubergreifenden Mathematikunterricht. 5th Solar Didactica, Solar-Energy World Exhibition 2002, in Berlin, June 14, 2002.

[17] Brinkmann, A. & Brinkmann, K. Biomass for Future Energy as a Topic in Secondary Mathematics Classrooms. 12th European Conference on Biomass, 17-21 June Amsterdam, The Netherlands 2002.

[18] Brinkmann, A. & Brinkmann, K. Promoting Renewable Energy Issues in Secondary Mathematics Classrooms. In: A. A.M. Sayigh (ed.). Renewable Energy. Renewables: World’s Best Energy Option. Proceedings of the World Renewable Energy Congress VII. 29 June — 5 July 2002 in Cologne, Germany. Amsterdam: Pergamon. Elsevier Science Ltd. ISBN: 0-08-044079-7.

[19] Brinkmann, A. & Brinkmann, K. Wind Energy in Secondary Mathematics Classrooms. Proceedings of the 1st World Wind Energy Conference and Exhibition. 04 — 08 July 2002 in Berlin, Germany.

[20] Brinkmann, A. & Brinkmann, K. Biomasse — Mit Mathematik warm durch den Winter. Istron-Tagung „Mathematik und Realitat" in Freiburg, Oktober 10-12, 2002.

[21] Brinkmann, A. & Brinkmann, K. Integration der Themen „rationelle Energienutzung" und „regenerative Energien" in einen fachubergreifenden Mathematikunterricht. Begrundung — Didaktisches Konzept — Aufgabensammlung. In: Hans-Wolfgang Henn (Hrsg.). Beitrage zum Mathematikunterricht 2003. Hildesheim, Berlin: Franzbecker, 145-148. ISBN: 3-88120-354-0.

[22] Brinkmann, A. & Brinkmann, K. Windenergie im Mathematikunterricht. Istron-Tagung „Mathematik und Realitat" in Magdeburg, November 06-08, 2003.

[23] Brinkmann, A. & Brinkmann, K. Mit Mathematik warm durch den Winter. Istron — Tagung „Mathematik und Realitat" in Magdeburg, November 06-08, 2003.

[24] Boer, H. Konzentrierende Kollektorsysteme. MUED-Schriftenreihe Unterrichts — projekte. ISBN: 3-930197-31-6.