Could electric vehicles be one solution to energy storage?
Maria Cox, MMTA
What if the electricity grid were to use the batteries in the growing numbers of electric vehicles to help ease the peaks and troughs in energy supply and demand and stabilise the grid? One of the big problems faced by the national grids of many countries is that even with a mix of electricity sources, there are wide variations in supply and demand, especially as we move towards higher use of renewables. The wind doesn’t always blow and the sun doesn’t always shine at the time of day when we all want to use our electricity (eg. early evening), and similarly it might be blowing a gale in the middle of the night when most of us are asleep. Electricity companies are faced with the problem of not having enough electricity for our use – and potentially having to buy it in at great cost – or absurdly, having to pay to get rid of excess power at certain times. Why? Because they aren’t able to store sufficient amounts of power and release it back into the grid at times of shortage.
However, there could potentially be a solution: imagine a few years from today when significant numbers of us will be driving electric vehicles, if car manufacturers are correct. We charge our car batteries, we go about our business and when we return to the house in the evening, we plug our cars in to recharge their batteries.
It appears that it would be possible for the power grid to use these thousands of batteries to store excess power and then draw back on that power when the grid is under pressure. It would potentially provide a huge amount of extra capacity at no additional cost to us as electricity users.
Obviously, there are some questions that would need to be answered, for example what would happen if the grid has just emptied my car battery to meet the nation’s power needs just at the time I have to rush out unexpectedly? I’m expecting my battery to be fully charged because I plugged it in when I got home, and suddenly it’s flat! It’s clear there would need to be some rules around when the grid could take our power, but that must be achievable. Similarly, car owners would need to be reassured that the additional charging and emptying cycles would not shorten the lifespan of the car’s battery. However, there is potential in the idea to solve the energy storage issues associated with increased use of renewables.
Inspired by: IOM3 Energy Materials Group Lecture – A Guide to the Surreal World of Energy Storage Materials: Understanding Materials Failure