How fast charging impacts electricity grid

With the popularity of EVs increasing, there has been several concerns regarding fast charging and how this will impact the electricity grid.

Fastned share some of its findings based on over 100,000 fast charging sessions and more than five years of operating a vertically integrated fast charging network.

Fast charging stations on medium voltage grids have unique properties that can play a role in stabilising the grid and absorb large amounts of renewable energy (solar and wind).

Large fast charging stations with more than 10 chargers are able to serve hundreds of cars per day yet require just one grid connection. This dramatically lowers the burden of connecting to grid companies.

Fast charging stations connected to the medium voltage grid are very suitable to be equipped with additional battery storage. On site batteries can increase the maximum capacity of the station during peak moments and in aggregate, these batteries can act as a large scale flexible resource for the grid operator.

Fastned’s data shows that aggregate demand at its fast charging stations follows a predictable and stable load curve during the day.

Fast charging happens mainly during daytime, when the sun is shining and more renewable energy will be produced. Increasing supply of solar energy can thus be directly absorbed by fast charging.

Fast charging is complementary to slow charging (which mostly happens overnight). Fast charging can thus help to spread the total demand for charging over 24 hours.

In the future, with more self driving EVs on the road, the value to the grid and renewable energy adoption can be increased further. Fully autonomous EVs can respond dynamically to price signals of fast charging stations to optimise for fast charging on moments of high renewable energy output.

As long as fast charging stations are connected to the medium voltage grid and prepared for future onsite battery storage, they can be a simple and grid-friendly solution to charge large amounts of EVs on renewable energy. Because large fast charging stations require limited land area and very few grid connections, they are very suitable to charge large numbers of EVs once electric driving become more commonplace.