Until recently, having a black box fitted to your car was all about saving money on your young driver car insurance premiums - but now pay-as-you-drive (PAYD) provider More Than is putting the systems to a different use.
In a planned trial of 1,000 vehicles, the cheap car insurance provider will use differently configured boxes to monitor drivers' eco-friendliness and provide feedback which could save them money on fuel bills.
"The whole idea is to look at changing drivers' behaviour and encouraging them to use their car more efficiently and responsibly," said a More Than spokesman.
The systems will watch for wasteful driving behaviour such as over-revving, long idling periods and unnecessary short trips, and highlight these for participants in a regular report.
"We might give feedback weekly or monthly," said the More Than representative. "It could be through a secure website, by email or even by text. We just have to find out what motorists want."
While participating in the scheme does not promise to cut the price of young driver car insurance, studies from the Energy Saving Trust have show that adopting more fuel efficient habits could shave £120 off your annual petrol bills.
"Does that make them 'green' boxes?" wondered Mike Page, spokesman for the young driver car insurance specialists at Hoot.

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