Bad news today for UK electric car startups. As we predicted back in August 2007, London Mayor Ken Livingstone has pushed through changes to the London Congestion Charging scheme that will give a 100% discount to conventional petrol and diesel vehicles in tax bands A and B. The new £25 charge for “gas guzzlers” and 4x4s in band G may grab the headlines, but we’re more interested in the impact at the other end of the scale.

We can all now forget band A – which is where electric cars live alongside painfully slow Polo Bluemotions – band B is the place where the average London punter will now want to be when the changes come in, on 27 October 2008. They will be able to run free through the congestion zone while drivers of the majority of cars - in bands C to F - will still have to cough up £8 per day.

Band B allows CO2 emissions of up to 120g/km and includes a wide variety of quite normal cars – personal transport that can actually accelerate and protect you in a crash. The roster includes some quite delightful little motors. Put up with the clatter of a small diesel lump under the bonnet and you can go charge free in an Audi A3, BMW 118d, Citroen C1, C2 or C3, Fiat Panda, 500 or Grande Punto, Ford Fiesta, Fusion or Focus, Mini Cooper D, Peugeot 207 or 308, Renault Clio, Modus or Megane, Seat Ibiza, Skoda Fabia,Toyota Aygo, Vauxhall Corsa, or VW Polo.

And even if you despise DERV, you can still dodge Ken’s tax by choosing a suitably feeble petrol-engined Aygo, C1, Smart ForTwo, Mitsubishi i, Daihatsu, Hyundai, or Fiat 500.

And of course you can still choose a hybrid Honda Civic or Toyota Prius, which will qualify by virtue of their low CO2 rather than their alternative fuel status. Sadly for smug Lexus hybrid drivers, discounts for alternative-fuel vehicles outside of bands A and B are to be withdrawn (although even then the RX400h 4x4 manages to creep into band F and will pay only the standard £8 fee).

So a sad day for those brave entrepreneurs and pioneers pushing for progress in battery-powered plastic snails, like GoinGreen and the Nice Car Company. Reasons to buy their wares just took a big and potentially fatal dive. And a good day for blinkered, money-grabbing politicians. A good day of course for conventional car makers of economical city cars. And, it has to be said, a bad day for congestion in London. After all, a BMW 118d is not actually going to create any less congestion than an Aston Martin V8 Vantage, even if the Bimmer is in band B and the Aston in band G.