A four-storey home in Delhi or elsewhere can run on minimum thermal power from the grid if the new guidelines for energy efficient homes issued by the ministry of new and renewable energy (MNRE) are implemented.
The voluntary guidelines for the residential sector in hot and humid areas recommends 15 energy efficient features for homes including installation of solar rooftop panels and solar water heaters that can substantially reduce energy requirement annually.
“If all the features are incorporated in homes up to four-storey buildings the requirement of energy from external sources would be bare minimum,” said Sameer Maithel, who had developed the guidelines under Indo-Swiss Building Energy Efficient Project. “Taller buildings will require more thermal power as roof-top solar generation capacity will remain limited”.
Implementing some of the measures like proper ventilation, use of light colour on walls and proper wall-to-window ratio would result in substantial savings on power consumption. About 20% of the cooling energy can be saved if internal and external walls have light colours and windows have extended overhangs. Use of insulation on walls and double glaze glass panes could result in saving of up to 50% electricity needed for cooling.
Ajay Mathur, director general of Bureau of Energy Efficiency — the statutory office for energy efficiency in India — said the cooling requirement of a room in a middle class home will go down from a 1.5 tonne air conditioner to a one tonne AC if the measures for one’s bedroom are adopted. And it would translate into about 30 to 50% less energy consumption for cooling.
A big bottleneck for implementing the guideline was removed by Delhi Electricity Regulatory Authority (DERC) on Tuesday — the day the guidelines were launched — by announcing net metering system for Delhi.