Questions are being raised over whether environmental benefits are enough to justify Boris Johnson splashing out �1.3 million so far on his idea for an electric car network across London when the ‘take up’ has been slow.

London Assembly members are examining the Mayor’s original plans for 100,000 electric cars with 25,000 charge points by 2015, including 1,000 vehicles in the GLA’s own fleet.

Boris has already had to revive his plans down to just 1,300 charging points by 2013—because there are still only 17,000 hybrid and all-electric vehicles in London at present.

“Questions need to be asked about whether the Mayor’s plans can be achieved,” said the Assembly’s environment chair Murad Qureshi. “We need to know if there will actually be enough environmental benefits to justify the effort and costs.”

Electric vehicles can cut CO2 and greenhouse gas emissions compared to petrol or diesel vehicles, the environment committee points out.

But they can produce higher emissions of NOx and SOx which could contribute to ‘acid rain’.

The Committee has invited experts to its meeting on Tuesday to discuss how to get more drivers to switch to electric cars and what environmental benefits it might bring. The meeting at City Hall, near Tower Bridge, starts at 10am and is open to the public.