The need for cooling Delhi homes has driven up the night-time peak demand to record levels. The starkest evidence of the powerful impact of residential use of ACs on electricity demand is the higher night-time peak demand compared to the afternoons, according to the Centre for Science and Environment.

A CSE statement said, “This summer, on several days, demand has peaked during the night – recording higher levels than the day-time demand. This has happened even when all commercial uses, including offices, retail and education institutions are closed at night.”

The impact of residential demand for electricity is so substantial that the average electricity demand on weekends is just 4 per cent lower than the demand on weekdays. This slight difference is caused mostly by an about 8 per cent drop in demand during the day time, while the night demand remains the same. In the early 2010s, day peaks during the weekend used to be higher than the night peaks; but last year, almost 95 per cent of the weekend night peak was higher, the CSE said.

According to the CSE, electricity consumption in Delhi has grown by almost 42 per cent between 2006-2007 and 2017-2018. Peak demand has grown by staggering 64 per cent between 2006-2007 and 2017-2018. On average, an electrified household in Delhi consumed about 260 kiloWatt-hour (kWh) of electricity monthly in 2016-2017, which is almost three times the national figure of 90 kWh. This is similar to the electricity consumption of an average German household.

Pointing out the faults on the policy front, CSE said, “Energy efficiency standards for ACs lag behind global best practices: Between 2013 and 2018, India produced over 26.5 million AC units, of which about 60 per cent were 3-star. A recently released report, ‘The Future of Cooling’ by the International Energy Agency, notes that when it comes to energy efficiency of ACs, India has the worst market average of measure of energy efficiency compared to major economies such as the US, Europe, Canada, China, Japan, Korea, and Singapore.”

During May, for as many as 21 days, late night peak demand has been higher -- up from 14 days in 2016. A typical summer day in Delhi has two peaks, one during the day (driven by commercial activities) and the other around midnight (driven by residential sector). On average, these two peaks have become almost identical now. The average day peak during May 1-May 31, 2018, was 5,280 MW daily during the afternoon (between 3.00-4.00 pm); the average daily night peak was 5,256 MW (11.00 pm-midnight) – a small difference of merely 0.5 per cent.