Denmark met its energy needs through renewables, but there's a catch

That kind of achievement itself underlines the need to find solutions for energy storage

Danish media reported that on Sunday, 11 June, the country produced 102.1% of the energy it needs solely from renewable sources – solar and wind power. The overproduction of green electricity is, naturally, good news but it needs to be taken in with a perspective.

Given the volatile nature of the sun and wind, especially in a northern country like Denmark, that kind of output cannot be reliably predicted and planned out. Last Sunday happened to combine perfect climatic conditions with plentiful wind and sunshine, something that happens fairly often in the month of May.

However, other seasons lack enough sunshine to ensure the production rate. And later in the summer, the sun actually gets too hot for optimal production of electricity, as some energy is also spent to cool down the solar panels.

What’s more, weekend production reached high levels because there is less demand then. For comparison, only a day later, wind and solar power could only account for 85.4 per cent of electricity consumption despite similar weather.

Better for drivers to charge cars during the day

On the occasion of the news, energy association Green Power Denmark’s chief consultant and analyst Kristian Rune Poulsen was quick to give some advice, specifically to e-car drivers.

In his opinion, as quoted by CPH Post, it is best if the car owners would charge their vehicles during the day in the summer, because that way they get to take advantage of the overproduction. This, on one hand, would optimize the supply-demand balance, but it would also result in cost cuts for the drivers, as they can save up to 50 kroner for each charge – the equivalent of 6.70 euros.

The volatile nature of renewable energy means that the next big thing for innovators, entrepreneurs and policymakers to figure out is to focus on developing reliable means for storing generated electricity so it can be used at peak times.