IN response to the letter by reader G F White (Wiltshire Times October 27), sadly his proposal is not the answer to the problem. The batteries used in electric cars are significantly larger and much more expensive than those used in petrol and diesel cars. 
The costs are in the order of thousands of pounds as opposed to around one hundred pounds for a normal lead acid battery. So the start up costs for an electric garage facility with a large number of charged batteries of several different battery types would be prohibitive.
More importantly exchanging a battery would be an expensive task which would take longer than a rapid part charge for a fitted battery. Usually the battery is fitted to an electric car during the manufacturing process and exchanging it would be akin to having a new engine fitted.
Some videos on line show the car body being lowered onto the battery pack during assembly as the battery pack weighs between 15 and 20 times that of a normal lead acid car battery. Fortunately battery design for electric cars is still evolving and improvements in charging techniques will no doubt bring the recharge times down.
James Kemp C Eng FIET
Liddington Way 
Trowbridge