A Contribution Towards Conservation of Natural Resources and Environment
Need for Energy Conservation:
Conserving energy reduces pressure on generation thus saving valuable natural resources. At the same time it helps in reducing the pollution to a great extent. For example, energy sector is the single largest contributor towards ‘Global warming’ i.e. Climate Change.
Though India has much lower per capita energy consumption, we are known for wasteful use of energy, with highest energy/ GNP ratio. Obviously, there is huge potential for conservation of energy in all sectors.
Energy conservation is not reduction in use of energy at the cost of economic growth, but is optimum utilisation of energy with least or no waste.
Contribution of Buildings in Energy Conservation:
Buildings are the largest consumer of natural resources and is responsible for their depletion at alarming rate. With increasing population, the situation will soon be beyond control, as dwellings too, consume a large share of commercial energy.
We all, the occupants of the buildings, can contribute to a large extent; in conservation of energy and protection of environment. Following areas have been broadly identified, which have potential for energy conservation.
A) Space Heating:
India has tropical climate. However, space heating requirement does exist, in many parts of the country, especially during winter. In Europe, space heating accounts for major sectorial energy consumption. For example, in FRG, space heating consumes 40% of energy.
The demand on space heating can be reduced in three ways: reduction in heat loss through walls, ceilings and windows, maximise the use of solar energy and waste heat recovery.
Heat lost in houses is generally through, roofs, floors, walls and windows/ ventilators etc. It can be minimised by improving the insulation of the houses. European countries, Canada and U.S. have certain norms and legislative regulations which specify minimum insulation standards. Heat loss through walls and ceilings can be reduced by use of double walls concept. It may be filled with insulation material e.g. wet/ dry blown cellulose.
The insulation can be further improved by use of fibre glass sheathing, foam polystyrene etc. For example,10mm thick foam polystyrene insulation on walls reduces the heat loss by 40% to 50% and 50mm thick insulation reduces heat loss by 80%. Additionally, 6 mm thick polyethylene sheet can be used as barrier against air leakage, wherever required. In general a compact R.C.C. house needs less insulation and heat loss through floor is lesser than heat loss through walls and ceilings.
Plural layered glass panels reduce heat loss through windows by 60% and windows should have few dividers, so as to have lesser leakages through joints. In extreme climate at some places in Europe, the windows have triple panes and the gap is filled with Argon gas. Low emissivity coating and edge sealing with organic material further enhances insulation. “Extract Air Windows” have the advantage that warm air is extracted through the space between the glass panes and circulated in the room.
Waste heat from the used hot water of bathrooms, washers etc. fire places and cooking ovens can be effectively recovered and used for space heating. Incidental heat gains such as cooking, hot water space heating system, electrical domestic appliances, illumination and direct and/or diffused sunlight, can be harnessed to reduce the space heating requirement. Better insulation also enhances the benefits of incidental heat gains and shortens the heating-on time.