1. What is solar passive architecture?
Solar passive architecture involves methods of collecting, storing, distributing and controlling thermal energy flow in a house by means of the natural principle of heat transfer. It makes use of the energy available in its immediate environment and effect energy exchanges through natural process to achieve thermal and visual indoor comfort.
2. Is solar passive architecture a new concept?
No. In olden days, climate - conscious designs were the norm. Many examples of historical buildings are testimony to the simplicity and common sense of solar passive designs. Built without the aid of architects and engineers, these buildings cleverly used sunlight and natural breeze to cool their interiors.
3. Why then are we re-inventing the wheel?
Because most of the buildings today are dependent upon external sources of energy while the natural sources are neglected. And energy is now a costly commodity.
4. Why are modern day buildings not climate- responsive?
It all started with the Industrial Revolution in the 17th century. Rapid growth of urban population demanded low- cost housing for the expanding labor force. Modern buildings with uniform "International Style" came up throughout the world irrespective of differences in climate. Enormous amount of energy is consumed in these buildings to achieve indoor comfort.
5. Why were the architects not energy conscious in those days?
With the availability of low cost electricity and fossil fuels (such as natural gas), worrying about energy efficiency was a waste of time. For the first time in history, the architects were free from the rigorous demands of climate and orientation. Use of mechanical systems and artificial lighting scored over natural ventilation and sunlight that in turn fired their imagination to design any structure anywhere.
6. When did we start looking back to good old techniques?
The infamous oil crisis in the late 1970s and the subsequent rise in fuel costs prompted the world to look back to solar passive techniques. Climate sensitive buildings can often reduce energy bills by 50-75% at little or no extra cost and some of them have proven to be cost effective at today's fuel price. Architecture has always responded to the times and energy conservation is the issue of our time.
7. Does the Solar Passive Building achieve total energy conservation?
Passive solar buildings take care of major part of energy conservation since most heating, cooling and lighting requirements are supplied by sunlight, shading and natural ventilation. The "low energy building" also employs the energy conservation techniques of using very heavy insulation or efficient energy gadgets. Both the techniques are used together for the same structure.
8. What about active solar systems?
In moderate climates, only passive solar designs are sufficient for achieving indoor comfort. In extreme climates, the support of active solar systems such as solar hot air, solar hot water and photovoltaic systems further reduce the energy consumption of buildings. It is desirable to integrate active and passive techniques into the buildings in such a way that its aesthetic beauty is not compromised.
9. Does the solar building look futuristic with high technology design?
The beauty of passive solar design is that, though the basic principles are simple, there are a great number of ways to harness the sun's energy effectively. Solar houses do not have to be identical, nor need they be dull. Many of the most efficient new buildings look surprisingly conventional.
10. Does the solar house become stuffy?
In extreme climates, the solar house is heavily insulated. It is fitted with an air- to- air heat exchanger that ventilates the building but prevents heat loss. Without this device, air could become unpleasant and unhealthy.
11. Does the solar house control humidity also?
The solar house mainly concentrates on temperature control and the humidity is controlled through ventilation only. In ver yhot and humid climates, additional dehumidification may be required for comfort.
12. Is it possible to retrofit the existing buildings with solar and conservation measures?
Replacement of old inefficient buildings with new ones would involve staggering costs. Making the existing buildings more energy efficient is thus the logical alternative though it is more difficult, costly and institutionally complex process. However the potential of energy saving is greater than for the most ambitious new construction.
13. Is it a practically accepted technology today?
A few lakhs of solar buildings have been constructed in western countries. In India, mainly the Govt. and institutional buildings have been constructed on this principle. There are many examples of individual solar houses also.
14. Can it be a good business proposition?
Developers and builders are now realizing that the solar design and the promise of reduced fuel bills can be a strong selling point, and they are approaching design firms for solar blue prints.
15. Is it possible to incorporate solar principles in small houses too?
The tin roofs, which spread through- out Asian and African villages, due to its durability, make the indoor conditions very uncomfortable. With minor changes and with little extra cost it is possible to make small houses more comfortable. Improving the energy efficiency of poor people's homes should be a major priority of all energy audit and retrofit efforts. With well-integrated programmes that have community support and that are revised over the years, the potential of improving world's buildings is immense.
16. What is the role of individuals in this field?
Slight changes in the life styles of individuals can create wonders. Simple, unexciting measures such as opening a window on a mildly hot summer day instead of turning on the air conditioner, or switching lights on only when necessary, can yield attractive financial returns.
17. What is the solar message?
Remember that climate sensitive structures work with nature and not against it. Our buildings would be more beautiful if they responded to energy concerns and had a more natural configuration. Achieving indoor comfort level with natural resources and providing the ambience of serenity are among the goals of today's architects.