Category Archives: SonSolar

Directions for Use

Printed directions for the use of the Sun Emulator are extremely brief and almost unnecessary because this heliodon is a model of our everyday reality. First, the model to be tested is placed at the center of the round table, its south orientation aligned with that of the heliodon. Then the cradle holding the seven rings is adjusted for the correct latitude by means of a single locking knob. Next, a twelve position rotary switch is used to choose the sunbath for the 21st day of any desired month. To simulate the daily motion, the appropriate ring is rotated by hand from sunrise to sunset. Other rings are then rotated to investigate solar access and shading patterns at other times of year. To

see what happens through the year at a particular time of day, the lights of all the rings are aligned and the rotating switch is turned to simulate the annual travel of the sun up and down the sky.

2. Applications

Although the Sun Emulator was developed primarily for architecture students, it is appropriate for a much wider audience, as will be discussed below. For architecture, landscape architecture, planning, and interior design students a heliodon has three separate applications: (1) the initial learning of concepts and principles, (2) the design process, and (3) presentation. As was described above, the Sun Emulator is an unsurpassed teaching tool. As a design tool, it can be used to actually assemble a design as, for example, when the length of an overhang is determined on the model by a trial and error method. Or the heliodon can be used as an analysis tool where a design, developed away from the device, is tested for its performance. In my own classes, I have students test models of designs they developed previously in studio. After the analysis establishes what works and what doesn’t, the students redesign their projects to be more solar responsive. Next, fast and dirty study (not presentation) models are built of an important window and shading system and these are then tested on the heliodon to determine what weaknesses remain for further redesign. A popular application among the students is for presentation purposes. They use the heliodon to photograph their models to document their designs’ solar responsiveness for juries and portfolios.

Homebuilders are another major user group. Most homebuilders are in fact designers. They often decide which building design will be used, what its orientation will be, where it will be located on a lot, what trees will be left standing or where trees will be planted, etc. Each of these decisions would benefit greatly from the understanding of solar responsive design principles. Developers are even more in need of this knowledge because street orientation has major consequences, since it will usually determine orientation of the buildings which are almost always aligned with the street rather than the sun. One of the most successful developments in the second half of the twentieth century, Village Homes in Davis, California, was designed by means of physical models tested for solar responsiveness.

Government officials also need to understand the benefits and practicality of solar responsive planning and design. Laws, planning regulations, and building codes generally do not encourage solar design because their writers were not convince of the benefits and the feasibility of solar designs. I have direct experience with a government official who after seeing the heliodon demonstration developed an interest in the potential of solar responsive regulations.

If homeowners and architectural clients are not interested in solar responsive design, then there is little incentive for building professionals to provide such designs. Thus, it is imperative that all who finance or control the design of buildings should be knowledgeable about the potential benefits of working with the sun, and ironically, many of these benefits come from strategies that cost little or are free.

In effect almost everyone should understand and thus believe the financial and environmental benefits of solar responsive design. This widely held understanding, I believe, is best accomplished by means of a "conceptually clear” heliodon. If the hands-

on science museums for children had heliodons, children would understand early on and in a lasting manner the logic of designing with the sun. Schools too could use heliodons in their earth science or physics courses. If children routinely learned about these principles, we would have future generations that would demand the benefits of solar responsive design because they would know that they are real, achievable, and economically wise.

3. Limitations

The Sun Emulator is an excellent heliodon for teaching and designing where high precision is not vital, which is the case for most building design. For example, the precise knowledge of the shading from a tree is meaningless since trees grow. Also weather is too variable to establish precise dates when sun or shade must be available.

Although the sun angles for the point at the center of the heliodon table are very precise, as one moves away from that point, in all three axes, error accumulates. Thus, small models are best and some larger models can be moved around so that the part of the model being analyzed is placed over the center of the table.

The highest precision in model testing is possible with sundials mounted on models tested outdoors, the only place where parallel light rays are readily available. Although such model testing is extremely precise, it is inconvenient, awkward, and conceptually unclear. It is awkward because you can’t test models outdoors at night, in the rain, or on cloudy days, and it is frustrating and uncomfortable under partially cloudy, windy, hot and cold conditions. Testing models outdoors requires the model to be tilted to account for all three variables of sun angles: latitude, time of year, and time of day. As described earlier these problems are both practical and conceptual in nature. Non-horizontal models must be well glued and prevented from sliding. They are also not easily analyzed since we find it hard to relate to buildings that are not horizontal. Consequently, I recommend outdoor analysis with sundials only after a design is ready for presentation purposes, or for fine tuning when high precision is required.

Although a larger heliodon could handle larger models, the Sun Emulator was sized so that it can still pass through a standard door, be completely fabricated at the factory, shipped fully assembled, and take up very little space when stored (less than 2 square meters) (Fig. 3). After unpacking or storage, it is only necessary to plug the heliodon into an electrical outlet and to rotate the model table from vertical to horizontal.

FIG. 3

The Sun Emulator in its storage mode. The cradle with the 7 rings is set for 0 ° latitude, as it would be to simulate solar geometry at the equator.

Although some other heliodons are more precise for larger models than the Sun Emulator, its "conceptual clarity” ease of use, and other advantages described above, more than compensate for its limited precision.

RES papers in the European Union

The fundamental strategic EU documents which express political will to support utilisation of RES are the White Paper "Energy for the Future: Renewable Sources of Energy” and the White Paper on European transport policy [6]. They comprise a range of
proposals and measures to accelerate the realisation of targets and planned tasks. They specify directions of further actions.

The basic legal act supporting the development of RES in European Union is the Directive on the promotion of electricity produced from renewable energy sources in the internal electricity market, which imposes on the members states quantity targets and regulations of promotion and support electricity generated from RES. Another legal act of great importance is the Directive on energy performance of buildings [7]. Other papers, including those on greenhouse gas emission allowance trading [8], on the promotion and use of biofuels in transport [9] and on Community guidelines on state aid for environmental protection [10] give EU recommendations on how to make our planet a greener and cleaner place to live in.

Why organise the SAMSA?

The Mediterranean basin area is one of the world’s primary regions where solar architecture has flourished throughout several centuries, as can also be recognised from remains of Roman and other regional architecture, and historic publications.

However, with the introduction of fossil fuels, many of the principles of solar architecture were ignored in modern building design — also in this region — despite knowledge of passive solar building techniques gained through many years of building experience. The resultant reliance on electricity for heating and cooling spaces in particular is an aspect that the modern Mediterranean inhabitants have come to accept as ‘normal’, despite other more environmentally-friendly and easily available options.

The underlying strategies and principles of solar architecture, such as natural cooling and ventilation, passive solar energy and daylighting are largely being overlooked, despite a periodic resurgence of energy and environmental crises (oil crisis, electricity blackouts due to over-demand, and the latest threat of terror attacks on large energy installations), and the resultant problems it presents to people. The presenters of this paper aim to point to the solution at hand for Mediterranean building designers and users, namely designing and building according to solar architecture principles and energy efficiency concepts, using clean energy sources.

Developments over the past decades in the field of renewable energy technologies (RETs), energy efficiency (EE), new materials and design tools — seen against the background of problems resulting from the use of fossil fuels — have reactivated an interest in solar architecture. There is a growing interest from a wide range of actors, from utilities, to users, to local and national governments, who recognise the need to change the approach, considering manyvaried aspects including the environmental impact.

However, some major obstacles exists in the Mediterranean context (but similar for also for many other regions as well). The current information and experiences regarding Mediterranean solar architecture is only available in a fragmented way. Such information is often poorly disseminated among the main role players in the building industry and among political decision-makers who need to formulate supporting policy.

In addition to this at tertiary education level there is clearly not enough focus on the consideration of energy efficient concepts and the application of solar architecture principles in modern building design. Architects and engineers often are not brought together during the course of their studies, thus not encouraging close cooperation in a real design situation. It is sometimes up to the tertiary education institutions to develop their own curricula. Should these not adequately reflect aspects that are important for sustainable building and energy efficient design, it is the role of other organisations — such as ISES and ISES ITALIA — to encourage them to change and meanwhile assist designers by providing them with training opportunities, presenting relevant information and tools on how they can design and build solar buildings.

All these aspects combine to result in a lack of preparation for building designers, who will increasingly be faced with the encroaching energy dilemma and the growing requirement of users to reduce building energy costs.

In response to this situation and the need for professional training in the Mediterranean basin area, ISES and ISES ITALIA started planning the Summer Academy for Mediterranean Solar Architecture (SAMSA 2002) in the year 2000. This regional capacity building event, was to be a workshop aimed at the transfer of relevant and useful experiences and knowledge by solar architecture and energy experts, addressing the culture and climates relevant to the Mediterranean basin area.

Integration of solar technologies in the built environment in past

In A Golden Thread — 2500 years of solar architecture and technology, solar architectures in ancient Greece and Rome are described (Butti and Perlin 1979). According to Perlin »Probably more significant developments in solar technology have occurred on Italian soil than anywhere else in the world."

Almost 2500 years ago, the ancient Greeks began designing their cities and homes taking into consideration the microclimate, in particular the sun, the winter winds and summer breezes. Olynthus and Priene are among the most important examples of ancient Greek solar urban planning. Greek principles were later to be found in Roman architecture. Vitruvio, a Roman architect who lived in the 1st century B. C., in his famous On Architecture wrote: "Buildings are correctly sited if region and latitude features have been taken adequately into account. In fact buildings should be built in one way in Egypt, in another way in Spain, still differently in Rome, and so on in all other areas having different features either of the land or of the Sun, whose influence on Earth depends on the distance from it which can be close, far or in between… therefore buildings must be oriented according to the different features of regions and climates."

Interest in solar architecture in ancient Rome was also fuelled by energy crisis, due to shortages and high prices of burning wood. Wood and charcoal were common fuels for Rome’s Baths and Villas, where space and water central heating systems, called hypocausts, were installed.

Heated air from hypocausts by burning wood in furnaces (praefurnia) flowed under floors and through walls by means of terracotta “tubuli”.

Heated floors and walls irradiated their warmth to the surrounding indoor spaces. In the Baths, water used in the caldarium, the warmest room of the Baths, was heated in large bronze boilers called "tartarughe della vasca" integrated into appropriately placed furnaces.

The installations described above can be seen at many Roman archaeological sites, where also Vitruvio’s precepts of

The remains of Pompeii, Herculaneum and the great baths in Rome and other cities of the Empire provide evidence of the important developments produced by the Romans in solar energy. From the first century A. D. on, under Augustus, and until Rome’s fall, the advances achieved by the Romans in the use of solar energy seem to have been put to fairly wide use throughout the Empire, though only among the wealthy classes.

Fig. 3 — Section of a typical Roman hypocaust’s heating system

solar architecture were followed.

The Romans had learned to make glass (very low quality compared to the today’s transparent glass) and to use the greenhouse effect to heat their homes, baths and greenhouses. Transparent surfaces were probably made also with translucent stones, like mica and alabaster, to trap solar heat, which was stored under the floors or in the walls with high thermal capacity.

For the first time in history, the Roman Empire enacted laws regulating “sun-rights” and similar matters.

In the first century A. D., for instance, the emperor Diocletian issued an edict setting prices for window glass (six or eight denarii per pound, depending on its quality).

Romans created a special room called heliocaminus heated by the sun’s radiation passing through south facing glass panes. The heliocaminus was the origin of legal actions on "sun — rights" due to its need for sunlight. Ulpiano, a lawyer of the II century A. D., claimed that the heliocaminus "sun-rights" must be protected. These rights were introduced four centuries later in Justiniano’s codes.

Rome for the first time issued a law to protect "sun-rights" and enforced urban planning and architecture principles aimed at promoting the exploitation of solar light and heat.

Therefore the archaeological remains of Rome, sometimes still standing nearly as they were two thousand years ago, are places where reflections on many aspects of the history of solar architecture and technology as well as of the history of energy use and civilizations are spontaneous, easily accompanied by strong emotions and feelings.

Facharbeit — A research work for upper grade school students

In several federal states of Germany a small research work is part of school performance for 11th or 12th grade students. In some federal states this work is obligatory for students, in others voluntary. This research work is generally named "Facharbeit”. It has to be documented in paper of about 10-30 pages, the demanded length differs in the federal states.

One of the main reasons for the integration of this work in upper grade public schools, is the aim to prepare the students in a better way for a study at a university. In Rheinland — Pfalz where I am going to school this aim is additionally supported by the prescription of a final colloquium on the research work.

It is up to the students to find a topic for their Facharbeit. Sometimes the teachers offer the students some topics to choose. A special advantage of the Facharbeit is the possibility of the free topic choice within a school subject, especially interdisciplinary themes are welcomed.

In Rheinland-Pfalz, the federal state of Germany where I visit the Gymnasium Birkenfeld, teachers have to take two works of this kind for minimum. It is up to the students to search a teacher who is willing to supervise their work. In this federal state the Facharbeit (here named BLL, for "Besondere Lernleistung") is voluntarily. The expected length of the paper is about 20-30 pages.

The students get grades for their works which can be integrated into the final result of the baccalaureate. This can only have a positive effect, a decrease of the final examination result is excluded. Therefore, there is a motivating reason for us as students to work out a Facharbeit.

It is possible and also desired to present the outcomes of the Facharbeit or parts of it in the competition “Jugend forscht” (or similar competitions), a competition in Germany for research works of school students. Here students may gain supplementary acknowledgements for their work.

In Rheinland-Pfalz students may not only choose their research topic freely within a given school subject, but they have also a free subject choice. This has an additional motivating effect for us as students, as we may deal in our work with any topic of our interest.

The European Master in Renewable Energy — Educating Renewable Energy Engineers

Katharina Krell, EUREC Agency


EUREC Agency is the initiator and coordinating agency of the graduate programme "European Master in Renewable Energy". The European Master in Renewable Energy is directed towards engineers that want to specialise in one of the renewable energy technologies, such as wind energy, biomass energy, photovoltaics, solar building technology or hybrid systems. A network of 7 European universities and research centres leading in renewable energy RD&D runs the course.

The course is of great interest to companies as it delivers qualified engineers equipped with the latest skills and the right experience for a successful career in their industry.

Demand for technical RE expertise

In 2000, a survey was undertaken by EUREC Agency as part of an ALTENER project, with the key findings[50] showing a growing shortage of suitably trained technical staff for the RE sector and a distinct demand for postgraduate courses. The survey indicated a severe lack of high level teaching materials, due to inertia in higher education institutions and the slow rate of recognition of the renewable energy’s increasingly important role in the energy mix.

Green Energy Fraction (GREF)

Climate protection requires new technologies, hence many kinds of renewable energy sources systems have been developed like wind, solar, geo-thermal and bio-mass, and a variety of strategies for marketing have emerged. The case of solar thermal hybrid systems is significant and is also illustrative for renewable energy hybrid systems of other technologies. The blending of fuel with solar has been invoked in order to enhance capacity, smooth power production and exhibit reduced costs for the mixed electricity output. The value of (1-FCR) defines the Green Energy Fraction (GREF) (shown on the left vertical scale) which represents the avoided-fuel fraction of the energy output of a system. It signifies the green (CO2-free) portion of the system energy output. This is the clean or green energy, which directly contributes to climate protection, and which we are targeting at. We want this green energy not to be lost upon blending with fuel energy. Both the (GREF) and (1-FCR) of a system must be based on the same reference standard.

A fuel-assisted solar thermal hybrid system

At the lower left side of Figure 1 a solar thermal hybrid system with a Rankine-cycle generator is modelled. The use of fuel enables the solar thermal SEGS (solar electricity generation system) to accomplish increased generation capacity, e. g., extend more hours of operation throughout the year far beyond the solar hours (say, 2000 solar hours as shown), by fuel firing at the SEGS generator (33.2% net efficiency). Partial fuel is used also during the solar hours in order to augment heat input when solar radiation is low and additional purposes. Three operation modes of such systems are noted. Mode 1 (the 2 kHrs point on the horizontal scale) indicates no use of any fuel during the solar hours (GREF = 1). Mode 2 (the full circular point), the use of 30% fuel, and mode 3 (the full triangular point), of 50% fuel.

At the point of 2000 operation hours with mode 1 the FCR will be zero, as there is no use of fuel. With mode 2, the FCR will be 0.11, and with mode 3, FCR of 0.2. The Green Energy Fraction (GREF) values will show 1,0.89 and 0.8, for the 3 modes, respectively. With full fuel
firing beyond the 2000 solar hours, the steep, relatively thick, three dashed lines (marked by SEGS 33.2%) show how fast the fuel-consumption grows. At 5700-6700 hours the lines reach the horizontal baseline standard level, which stands for the fully fuel fired CC (gas turbine combined cycle) (FCR=1). In other words, by operation for that period of time the solar-hybrid has consumed as much fuel (and produced emissions) as a 60% efficient fuel fired CC will do during the full year 8760 hours. At around 8000 hours, the solar-hybrid will have produced emissions much more than the CC and nearly as much as a fuel fired Rankine cycle running at a 40% level conversion (which is a secondary standard). In terms of GREF (green energy fraction) the green energy (fuel avoidance kind of energy) which has been produced by the solar system during the solar hours, now will largely diminish or be totally wiped out because of the extended operation hours. This green energy annihilation results from the long hours of firing fuel relatively inefficiently (33.2%) as compared to the baseline standard of 60%. It may also be nearly so with respect to the secondary standard of 40%. The differences between the 3 modes are noticeable.

The object and main aims of the project

The institution selected for the project is a Polish school — Gimnazjum nr 4, located in Warsaw in Ursynow district (Fig.1). At present there are 664 pupils, aged 13 -16 years old. Gimnazjum nr 4 is a state school. Together with basic education the school gives the opportunity to develop individual capabilities and interests. Pupils can advance their skills in different sports, take part in additional math, physics and computing lessons and attend to the school art & theatre group meetings. Since last year the school has undertaken a new task, the so called "School with class", which aims to upgrade the level of teaching and learning. The "School European Club" has been also founded aiming to promote the idea of Poland’s accession to European Union and the benefits for our country thanks to this process.

Fig.1 Gimazjum nr 4 in Ursynow, Warsaw. The target school for the project.

The concept of the "Mini solar laboratory" project was that the lab is owned by and based at the school and it

involves the pupils as much as possible in the project. The school has relevant classes in maths-physics and computing. It was decided that the pupils should learn about solar energy, not only by seeing the display material and the equipment but also by doing science project work.

The main aims of the project are as follows:

• to disseminate information about solar and other renewable energies and sustainability using an operating solar system;

• to provide an educational resource on solar thermal and photo-voltaic energy for secondary school pupils in Warsaw;

• to assure an increase in the awareness of renewables in young people through the process of theoretical study and experimental work on solar energy;

• to implement the idea of environmental protection through renewable energy applications;

• to involve school pupils in the process of construction of the solar system, its use and promotion.

In Poland there is a lack of literature on renewables and energy conservation for teenagers. Therefore it has been decided that educational materials should be prepared for the project and disseminated both during and after the project’s close. It is expected that a good deal of publicity and educational value will spin off from this project. What is more, it is intended to raise awareness of Renewable Energy and its potential, not only amongst young people in schools, but also in the general public. It is important that thanks to the project the role of the school as a major driving force in improving the awareness of young people of energy conservation and environmental protection has increased.

The one-year project started in February 2003. Scientific and technological management of the project was provided by the Polish side with co-operation of the British partners. The project is now at its end. Most of the tasks have been already fulfilled and some of the achievements can already be summarised.

Alternative Tools

Computers with solar 3-D programs are an alternative for the analysis and presentation applications of heliodons. However, for the initial learning of the broad concepts and for developing a mental model of the solar geometry as related to buildings, heliodons with conceptual clarity are far superior.

Learning the complex geometry of the sun as related to a building is like learning the street pattern of a complex medieval town by driving around it in a vehicle that has only one window, the windshield. A much faster and deeper understanding of the town would occur by exploring on foot. Not only is one free at all times to move in any direction, but also one is free at all times to look back or sideways. Because every view is in complete context of where one is, a mental pattern of the town will emerge faster,
be more complete, and last longer than through a controlled drive-through. Thus, I believe, the initial learning of solar geometry will always be better with a heliodon like the Sun Emulator than with a computer program.

For the student still new to this knowledge, a heliodon would also be very useful in the analysis stage of design. It is not easy to know how a solar access analysis should be performed using a computer program (i. e. what time of day or year should be investigated). A heliodon’s intuitive clearness and immediate feedback helps in planning and performing a solar analysis.

Even at the presentation stage, a heliodon can be more advantageous than a computer. Although the presenter may not need the heliodon’s conceptual clarity, the audience, which is often much less informed about solar geometry, would understand the logic of the solar responsive design more easily and believe in it more fully by seeing it through a heliodon.

For many years it was believed the 3-D computer modeling will replace the need for physical modeling. However, at the Auburn University School of Architecture, physical modeling is as popular as ever even though 3-D computer modeling is also extensively used. We evolved in a world of physical objects, and it is therefore not surprising that physical models are so engaging, immediate, and intuitively clear.

4. Conclusion

It is hard to believe that a rather simple mechanical device could be a such a powerful teaching and design tool. It is also hard to believe that such a device could have a major impact on our energy future, the environment, and especially global warming. My 27 year teaching experience with heliodons makes me believe that "conceptually clear” heliodons truly are powerful teaching tools that can greatly convince and motivate people. Also since they never wear out and will never become obsolete, they are a good investment for creating a better future.

More information about the Sun Emulator is available from my Auburn University website: www. cadc. auburn. edu/sun-emulator and the manufacturer’s website: www. hpd-online. com

RES policy in Polish governmental documents

In the accession process Polish legislation must be adapted to EU legislation in all areas, including the area of renewable energy.

For some time past intensive work has been carried out to adapt rules, regulations and procedures to join effectively the European system. Within strategic documents assigning a course of activities of national development in the field of RES the following should be quoted as the most significant:

* Development Strategy of Renewable Energy Sector (adopted on 5th Sept. 2000,

passed by Parliament on 23rd August 2001) [3]

* Notes on Poland’s Energy Policy to 2020 [11]

* Sustainable Development Strategy for Poland to 2025 [12]

The most essential legal acts include the following:

* The Energy Law [13]

* The Environmental Protection Law[14]

* The RES Law [15] (in preparation)

* The Quota Obligation Ordinance of Purchasing RES Electricity [16]

* The Amendments to the Quota Obligation Ordinance [17]

Amendments to the Energy Law have necessitated the passing of the Quota Obligation Ordinance and subsequently an amendment to this ordinance. According to the ordinance distribution companies are obliged to purchase a certain amount of green electricity, which in the total amount of sold electricity in 2001 exceeded 2.4 % in 2001, and 2.5 % in 2002, the predicted goal being 7.5 % in 2010 (Table 2).

Table 2. Obligatory purchase of electricity from RES for distribution companies


Green electricity share [16]

Electricity share generated in combined energy sources [17]




























At present a matter of urgent importance is to produce the RES Act which would compose the solid framework for RE investing in Poland. An inter-departmental group for Implementation Development Strategy of Renewable Energy Sector has been appointed to conduct legislation works on the project of RES Act to regulate the fundamental issues in transposition and harmonisation an environmental and energy policy (especially with the Directive 2001/77/EC). Unfortunately, the administrative procedures related to the approval of RES project are complicated and long-lasting. Since September 2003 several versions of the Act have been drafted as a result of discussions held during a number of meetings and conferences on various levels. The creation of national support schemes by introducing Green Certificates system market, subsidies, soft loans, higher prices of RES energy and planning of RES development on national, regional and local levels is taken into consideration, but the current project of the Act does not provide required support for renewable energy development and thus should be reconsidered.