How can I work out the residual value of an electric car with leased batteries, like my Renault Fluence?

I've just bought (not yet collected) one of the 'pre-launch' (January 2012) Renault Fluence ZE cars that have been offloaded into the dealer network and seem to have appeared in numbers in the last couple of weeks. The cars had variously been used for photoshoots, magazine and website tests and demonstrations. At 18 months old they are being sold off at £9000 each with 2000 - 3000 miles on them. 'Does not include batteries', of course. So, very soon I'll be happily feeding in feedback and mileage figures on the cars to you / the 'mpg' site for 'real' usage.

I've read that CAP won't give residual values on Renault EVs because the batteries have to be leased and the car owner never actually owns them. Should I take a chance on finance? Are the high residuals predicted pie in the sky?

Asked on 28 September 2013 by CMB, via email

Answered by Honest John
The residual on the original list price (sans batteries) of £21,845 for the Expression and £22,745 for the Dynamique is already only about 40 per cent after 18 months. But subtract the (soon to be unplugged) £5000 plug-in grant, and residuals after 18 months work out at 50 per cent. From now on the value will slide more gradually. I thought they would make quite good taxis. I can't comment on buy vs finance because the FSA does not allow me to.
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