Volvo’s recent campaign was designed to address what it saw as an unfair charging structure under the old rules, which enabled drivers of alternative fuel and hybrid vehicles to avoid the £8 entry charge despite emitting more CO₂ than many conventional petrol or diesel engine cars.

The new rules mean that any car, regardless of powertrain, will be entitled to a 100% discount on the London Congestion Charge. Volvo’s current range includes three 99g/km CO₂ models – the C30, S40 and V50 DRIVe models.

Motorists can register for the Greener Vehicle Discount from 4^th January, subject to a £10 annual payment per vehicle, provided their car emits less than 100g/km CO₂ and meets the Euro 5 standard for air quality.

With electric and hybrid plug-in vehicles set to arrive in the UK over the next 18 months, all of which will have significantly lower emissions levels than today’s cars, Transport for London said it would continue to monitor developments in the market and keep discount criteria under review. Another review will be conducted in 2012, when officials will decide whether or not to reduce the 100% discount threshold to vehicles emitting under 80g/km CO₂.

Volvo currently offers three models with CO₂ emissions of just 99g/km – the C30, S40 and V50 DRIVe. It has also shown a V70 estate with plug-in hybrid technology that emits less than 50g/km CO₂ – technology that will be launched in 2012 – and prototype versions of a full battery-electric C30.

Peter Rask, Volvo Car UK’s Managing Director, said: “This decision recognises the huge progress made by manufacturers in reducing the emissions of conventional petrol and diesel engines to levels that are, in some cases, cleaner than those of hybrid vehicles.

“It levels the playing field for drivers seeking a true low-emission vehicle and is a genuine victory for Volvo and emissions equality in the UK.”