The new Lotus Elise and Exige benefit from up to nine per cent improved fuel consumption and lower carbon dioxide emissions.
The Lotus Elise S will benefit from the greatest improvement in fuel economy, rising from 34.0mpg to 37.2mpg.
Lotus says the improvements have been achieved by using lightweight materials and more efficient engines.
Mike Kimberley, CEO of Group Lotus plc, said: "The Lotus philosophy of performance through light weight is even more relevant in today's emission focused ecological world.
"This design philosophy has enabled Lotus to offer fantastic levels of performance, with Lotus cars being some of the greenest performance cars on the market."
Kimberley also pledged that Lotus would continue to push for environmental gains.
"We are at the cutting edge of green transport technology and we will continue to push the boundaries with our green research and environmental strategy," he said. "We are keen to ensure that Lotus as a company and its products offer an ethical, green option that appeals to our customers."