mickthemaverick wrote: 03 Dec 2019, 13:10
Considering this issue in general, it occurred to me that local charging points could be installed using large capacity batteries and commercial wind generators. The generators are capable of producing 3-4Mwatts now so that when the wind blows power could be stored in batteries under the service station where the current tanks are, and then tapped as required for rapid charging. This method would remove the need for local network loading and also have the advantage of guiding you to a station by sight of the wind generator. Of course once the batteries were drained you would need to wait for the wind which is a failing but at least you would get a free hook-up, ie: there would be no charge!!
Most rapid chargers in the UK today are 50kW however 150kW and 350kW rapid charging standards exist, have some roll out already, (mostly outside the UK sadly) and would place such high instantaneous demands on the local grid interconnect (if you had say 8 chargers) that there are already companies who are designing and building rapid charger clusters backed with local battery storage.
The idea is that the on-site battery charges from the local grid at a lower peak power rate, then delivers high peak power to cars over a short period of time, and has enough energy to fully charge several cars from what it stores. Essentially it smooths out the demand on the local grid interconnect so that instead of peaking to say 1MW with several cars charging at once then dropping to near nothing again when the charging stalls are idle it might draw an average of 100kW across the day.
This greatly reduces the burden on the local grid infrastructure. Furthermore they plan to make this storage two way and act as distributed grid storage. In other words not only can the battery supply cars charging at the site, it can supply energy back into the grid at peak times if it is not being consumed by charging cars and grid demand is high, like the hornsdale wind farm battery bank in Australia.
To make it possible for renewables like wind and solar to provide a larger percentage of the current base load there has to be a lot of grid attached storage available, (there is very little at the moment) and preferably distributed around the country where power is needed to minimise the load on the main interconnects.
The companies putting in these battery backed rapid charger cluster installations see an opportunity to also provide grid stabilisation and storage services back to the national grid, and there is a great synergy there as the local battery can do double duty load smoothing for charging cars and grid storage for the grid itself. In fact I've seen some suggestion that they might actually make more profit from the rapid charger site providing the grid storage services than actually charging cars!
If nothing else, if they need the battery for the high power rapid charging hub to work anyway, any money made feeding power back into the grid during peak hours is money from otherwise idle equipment.
You're unlikely to see wind generators at rapid charging sites however there are already rapid charging sites in the UK that have both local battery storage and solar panels to supplement the grid connection, in particular those in Dundee:
https://www.bbc.co.uk/news/uk-scotland- ... l-49796127