Tesla vehicles at charging stations outside a store in Rocklin, California, America
Credit: Bloomberg/David Paul Morris
SIR – It is proposed that electric car owners could connect their cars to the National Grid and allow the energy in their batteries to take some of the load at peak times (report, July 28). But such use would seriously compromise battery life.
A typical lithium-ion battery has a life of about 1,000 cycles. For a car like a Tesla S, a 100kWh battery costs about £10,000. So each charge cycle costs £10 – or 10p per kWh – in battery wear and tear alone.
This sum of 10p per kWh is nearly twice the current wholesale price of electricity. Unless car owners are prepared to bear the extra wear on their batteries without compensation (and who would?) the price of electricity would have to increase very significantly.