RE: Oxford superhub - 44 more sites secured13 Jan 2020 12:29
Lindon - as is de rigeur with political announcements these days it is hard to know what exactly it is that they are claiming . Is it 2.2GW of battery storage, or 2.2GW of private individuals's cars that are connected to EV chargers? Or is it a mix of both ?
2.2GW / 44 = 50MW per site. 4,500 rapid eV charges works out at roughly 100 chargers per site. So on the surface of it that looks like half a megawatt power per car charger. That is insanely high so I wonder if the curse of the energy journalist, the 'h' in GWh has maybe again been missed off and it should read 2.2GWh (i.e. at a lower overall power of maybe only 12.5MW per site - that is still potentially 125kW per charger)
Imagine each charger works is used for 2 hours, twice a day at 100kW power. That would work out at an energy of 100x 2x2x100 = 40MWh per site so it looks like a 50MWh battery might be just about right for a 'charging park' of 100 charging spots, possibly outside a supermarket or motorway service station.
How big might such a battery be ? well if you assume 1MWh per 40 foot shipping container (8 foot wide), then you need 50 containers footprint. Each container is about the size of 2 car parking spaces, so 100 parking space in all. Battery and parking spaces occupy similar footprint, so not altogether crazy. If they were VRFBs then you might even consider the idea of packing the VRFBs tightly together and driving the cars on top of them if you are really concerned about space.
So this £1.6Bn of private investment - what is that all about ? - if we assume the total battery capacity is 2.2GWh then that would work out at £730 per MWh, or USD 946 per MWh - well in excess of the prices that are currently being quoted for both Lithium-ion and VRFB battery builds (though of course if you elect to buy the cheaper Li-ion unit you would be having to replace it every few years) - leaving some more money left over for installing the charging stations and paving the car park.