The Power of Diwali when the UK lights up


Diwali, Deepavali, or Dipavali are names for the Hindu festival of lights. It is celebrated in the autumn when the days get noticeably shorter. This year it starts on November 6 or 7 and is celebrated for 5 days. The date of the celebration depends on the lunar calendar (it’s on the 15th day of the month of Kartik, Hindu’s holy month). The word “Diwali means “rows of lighted lamps.” Houses, shops and public places in the Hindu community will soon be lit up to celebrate, with small earthenware oil lamps called diyas decorating the shops.

There is a festival of lights in most religions, really intended as a joyous occasion to counteract the gloom from the longer nights and the colder weather. The Diwali holiday story is a tale of victory, celebration of wealth, and the triumph of light over darkness in spiritual terms.

Hinduism is the fourth largest religious population in the UK, and the holiday is celebrated by about 817,000 Hindu people living in the UK.


The UK normally produces a total of 126.4 million kw/year total, but power demand is a very sensitive social barometer. It varies with the season and even when certain television programs are on. The demand is higher in the Summer (averaging around 40,500 MW) than the Winter (averaging around 30,500 MW).

Using Christmas as an illustration, the electricity demand during the sequence of traditional Christmas events in 2014 showed during the sleep hours, power demand averaged around 25,000 megawatts. When presents were being opened demand increased rapidly from 27,000 megawatts to close to 35,000 megawatts. The peak happened during the turkey cooking period to a little over 35,000 megawatts. While the telly was being watched, after the meal, demand slowly sank from about 34,000 megawatts down to about 28,000 megawatts.

The most likely effect of Diwali on the power grid

This means that power usage increased by as much as 40 percent in one day. Experts say that “the economics behind festivals is a precarious territory.” For a medium-sized festival for about 30,000 people, it is estimated that 3.6 megawatts of power will be generated over one weekend. Normally, the whole country is using 4.86 megawatts of electricity in a weekend. The festival will likely therefore increase usage by 26 percent that weekend.

With this estimate in mind, one can apply the same generalisations to estimate the effects of Diwali on the UK grid. Judging by the experience of Christmas, up to 35,000 megawatts of electricity could be generated per day during the festival. Judging from the experience with festivals, up to 39.2 megawatts of electricity per day could be generated by the 7-day festival of Diwali.

The effects of the festival could be somewhere between Christmas and a public festival, 35,000 and 39,200 megawatts per day. The seven-day holiday can increase electricity demand between 15 percent and 28 percent.

Large festivals have significant effects on power generation

Estimates provided here are theoretical, but a few things are really clear. The power demands on the grid are very sensitive to public behaviour, fluctuating with mass popular activity in a daily rhythm. Special events and holidays do have significant effects on power demand. Festivals and special events that require power can create a large demand for power generation. Effects of festivals and holidays may mean increases on power generation as large as 28 percent.


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