Independent (UK): All the talk of electric cars and emission-free vehicles is fine for city dwellers, but spare a thought for farmers, who know what gas-guzzlers really are. Depending on usage, tractors can average as little as 10 miles per gallon (over 23 l/100km), as power rather than fuel efficiency is the primary concern for agricultural users. For heavy users, this means an expensive fuel bill and a lot of pollutants – but one company thinks it’s got the answer. Later this month, a …