One point that may be of interest to you is the 2005 EU Consumer Practices Directive incorporated into UK law in 2008 (Ref: 2005/29/EC). As I understand it, within your context, it means that any commercial operation that claims Zero Emissions from an electric car without clearly pointing out that this refers to the tailpipe only and that emissions take place at the power station would be liable to prosecution. (However, under the present 'mindset' in our current legal system they could easily get away with it; judging by the response I got from the Office of Fair Trading.) I'm sure your avid readers would appreciate being informed of this.