THE DESIGN OF NEW CONFIGURABLE SOLAR ROOFS: TOWARD A NEW PARADIGM FOR SUSTAINABLE BUILDINGS.

JUANICÓ L.E.

Solar Collectors: Energy Conservation, Design and Applications

Nova Science Publisher

Lugar: New York; Año: 2009; p. 191 - 220

It is well known that many different conceptual designs are created at the beginning of every new technology. These earlier designs seem to come from a “brainstorming” process, since most of them represent radical designs, not self-limited in their creation process by a budget, manufacturer, marketing and other practical aspects that must be considered in the development of a commercial product. For this reason, most of them are discarded at the next stage, when they must become a commercial product. Thus, in this second stage it is usually observed than a certain technology wins the market. Meanwhile, the commercial manufacturing process continues and new products derived from the initial design are created following a trial and error process; it is commonly observed that gradually this emerging technology achieves its maturity. At this moment, (thinking now specifically about energy technologies) it is feasible for engineers to create bigger machines with almost no uncertainties regarding performance. This way, lower specific costs (in terms of U$/kW) and hence, higher economic competitiveness can be achieved. From here on, this technology attracts most of the investors and finally emerges as the winner in this technological competition. However, since investors and managers prefer low risk options, the creation of new radical solutions is scarce within this leading technology. In the third stage of development, we will observe only minor changes to the “accepted” design. The emphasis is usually placed on obtaining better economical competitiveness by means of manufacturing cheaper products; this implies manufacturing bigger machines, which in turn implies higher investments. This last condition always encourages selecting projects that guarantee the lowest possible risks. Hence, in a process driven by this negative feedback, the creative mind that started this story could be finally “unemployed” by his own enterprise. It is paradoxical that although successful enterprises that have started with a good new idea and claim to have innovation policies they are not a fertile ground for developing new radical designs. Following this trend, a proven technology generally achieves a “gigantism level” in the last four stages of development, until this is substituted by another technology that is always promoted by a different group. This figure can be applied to many energy technologies, like gas turbines, steam locomotives or nuclear reactors, among others. For example, let us consider now the modern age of wind turbines for electricity generation that started in the early seventies after the first oil crisis. At that moment many different designs of windmills were proposed (the Sabonius, Darrieus, Musgrove arrow, Madaras, etc.) but all of them were abandoned after that single ‘winner’ design emerged (Paul Gipe, 1995). This design (a horizontal-axis tripale rotor mounted above a tall tower), well established in the early eighties, has survived without major changes up to the present. It has followed the usual path, increasing the size of machines in order to achieve lower specific costs. The small turbines of the Californian boom of the eighties (with a few hundred kilowatts) are being substituted now by the giant megawatt turbines, but both are almost equal from the point of view of their conceptual designs. From the above discussion, it is important for a designer who wants to create a breakthrough design in order to solve an old problem (like the issue of constructing more sustainable buildings) to recognize this “inertia” to the development of new ideas according to our preferable organizational mode. Moreover, this is a valuable lesson. It is always recommended to start our creative work by studying all the older designs created at the beginning of this technology development. Besides being an interesting exercise for every designer, two particular issues should be considered in this assessment. First, we can always recognize that a radical design is based on a different approach that critiques some aspect of the most accepted design. This questioned aspect was not properly addressed at that moment (this being the reason why the design failed), but in fact, it can be useful now because it shows us new design dimensions (literally, it opened a new door that was not seen before). Therefore, we can ask ourselves if this proposal could help inspire new ideas. We emphasize the concern about the temporal framework, because it always implies a correlative technological framework. Thus, accordingly to the technological evolution of the world, many concepts that were not practical in the past might be feasible today (like what has happened with many of Leonardo Da Vinci’s revolutionary ideas). The second issue that we should keep an eye on relates to the previous point just described, but in the opposite direction. It consists in pointing out the drawback that did not allow it to work at that precise moment. Again, considering the temporal condition now it may be easier to solve design drawbacks according to new available technology options. Let us illustrate both rules using a simple non-technical example that can be easily understood by every one, let’s consider the design of ashtrays. Let us suppose that you have been asked to design a new ashtray as invisible as possible. The response from the classical design could be to use a transparent material. But suppose that while searching older designs, you find a radical proposal from the nineteenth century that consists on creating an air current by means of a hand-operated fan. In relation to the first rule and comparing this design with the conventional one, many new design dimensions could emerge: Why does an ashtray have to be only a recipient for ashes? Why not collect the smoke too? Why does this recipient have to work only under gravity forces?. The reader can include other questions, but the point that we want to make is that, even this simple example holds many underlying lessons. In relation to the second rule, it is easy to recognize that modern electrically-operator vacuums could be used now in order to build a practical prototype of the “air ashtray”. So, new technologies available now can transform an older awkward concept into a practical one. Finally, it is possible that this design might not be suitable for most users and never pass the conceptual design level, but maybe it could serve as an inspiration to design a new ashtray that stores the smoke together with the ash, or maybe using electrostatic forces to collect the ash more efficiently. This last point shows that a designer needs to keep an open mind and that the inspiration can come from different sources. If the reader feels that this last sentence is similar to others usually applied to artistic subjects, let me point out that in my modest opinion and personal experience, the creative labor in engineering could benefit from ideas taken from other fields. Undoubtedly, there are similar elements in every creative process. The purpose of this introduction is to stimulate the reader to play an active role in the creation of new sustainable buildings. In this chapter a new paradigm for low-energy buildings will be proposed. This new approach was not originated by an architect. Indeed, I feel this handicap was my main advantage; since I don’t need to follow any school of architecture studied previously; I was free to discuss and question any part of present paradigms about “what a house is supposed to be like”. We will construct this new paradigm through different designs that will be presented and discussed here. Moreover, since it is actually an open design concept, I expect to see new designs along this line coming from other designers in the future.