If 2050 is a little too long-term to conceptualise, the Prime Minister recently announced a major component of the transition, which is for the electricity grid to go zero carbon by 2035. That’s only 13 years away. If you think that still sounds distant, bear in mind that 13 years have passed since 2009, the year Barack Obama was inaugurated as US President and Captain Sully made his heroic landing on the Hudson. It seems like yesterday.

The challenge comes into full focus when you note that last year, we used about 330 TWh of electricity and 40 percent of that came from fossil fuels. Renewables produced 43 percent, with the rest coming from nuclear and imports. The fact that more electricity came from renewables than from fossil fuels is a laudible achievement that should be celebrated. However, it is a little like passing an early mile marker when running a marathon. There are far bigger challenges ahead.

One of the biggest problems is that power generation by wind and solar depends on the weather. At present, when conditions are favourable, there’s more than enough to go around, but when conditions are sub-optimal, fossil fuels (usually gas) pick up the slack.

Clearly, having an effective way to store up the energy that’s produced on sunny, windy days to use when the weather changes would make an enormous difference. A number of options are being explored right now, including hydrogen storage and even using electric vehicles as temporary storage batteries while they are not in use.