B) Space Cooling:
In Indian context, space cooling plays major role in providing thermal comfort and consumes major share of energy. Solar passive cooling is a method in which external thermal load e.g. direct sunbeam, heat by conduction and hot air infiltration, is either blocked or partly diffused. With study of path of sun at a particular place, orientation of a building can be fixed, so that it receives minimum direct sunbeam. Walls in east and west side should be shorter, so as to reduce the wall area exposed to direct sunbeam. Provisions of verandas/ balconies on east and west side keeps the adjoining walls cool. Provision of chajjas & sun-breakers in place of louvers adds to effectiveness of passive cooling.
The heat by conduction comes mainly through walls and ceilings. Light colour shades of external walls absorb minimum heat and highly textured walls absorb less heat than flat walls, due to self shading effect. Waterproofing of terrace, with light coloured glazed tile pieces, reflects maximum heat.
Lawns and grass patches, reduce heat reflection from ground and help in keeping the surroundings cool. Trees can be a cost effective shading device, as compared to R.C.C. fins. Evaporative cooling through large and shallow pools, courtyard fountains etc. has been an essential feature of architecture since ancient times. West wind can be trapped and directed to improve space cooling and ventilation. Internal thermal loads can be reduced to great extent by local ventilation and proper zoning of the rooms.
Use of air conditioning in offices, computer rooms, residential and commercial premises and hotels etc. is increasing rapidly. Same is the case with refrigeration in industries and agricultural sector. Improved insulation, combined with solar passive cooling techniques, can greatly reduce the loads on air conditioning and refrigeration equipments. Spaces which require cooling should be confined. False ceiling reduces the volume and hence the load on the air conditioner. Excess illumination, electrical control gears, ballasts etc. increase incidental heat, hence need more attention in Interior design and equipment selection.
C) Domestic Appliances:
Growing demand of consumer durables in urban sector, indicates the potential for energy conservation in this area. Electrical heating appliances consume major energy share in this sector. Since heating is the most wasteful use of electricity, alternate fuels and solar thermal systems have potential of replacing electricity.
Energy consumed by control gear is much more than generally thought. For example, conventional speed regulator of a fan, at times consumes more energy than the fan itself. Since appliances produced with modern electronic technology can reduce energy requirement by more than 60%, energy labelling of consumer durables is a must.
Energy demand in Computers sector has achieved significant proportions in recent years. Today in U.S; energy consumed in this sector is 5% of total energy consumed and is expected to grow up to 10% by the turn of the century.A ‘sleep-mode’ device has been introduced by which the computer goes in to low power state when it is not active.