The Automobile Club de l'Ouest and FIA have confirmed full details of the 2014 LMP1 regulations, which will be based on a variable fuel allocation according to cars' energy recovery systems.
The Le Mans and World Endurance Championship regulations will be further opened up from 2014 to allow a greater variety of energy recovery systems to be employed, with the fuel allocation per lap decreasing for cars with more powerful hybrid devices.
A car with a 2MJ hybrid system will get 4.8 litres of petrol or 3.93 of diesel per lap, compared to 4.42 litres of petrol or 3.56 of diesels for cars with 8MJ hybrid systems. At present, LMP1 cars' recovery devices are limited to 500KJ.
The ACO also confirmed that non-hybrid cars run by private teams will be allowed 4.95 litres of petrol or 3.99 of diesel in an effort to ensure that independent entrants can challenge the factories without investing in energy recovery technology, as revealed by AUTOSPORT in March.
ACO sporting director Vincent Beaumesnil said that while reducing fuel consumption was at the core of the new regulations, it was considered vital to ensure that performance levels and easy to understand racing were maintained.
"We hope to reduce fuel consumption by 30 per cent compared to current cars, with the same level of performance," he said. "The 24 Hours is a spectacle and we didn't want to turn it into an economy run.
"It's important to allow drivers to go flat-out. From 2014, you'll have to be quickest and have the best thermal energy.
"We hope that engineers will be able to express their creativeness. We want manufacturers so we have to give them guarantees, and private teams have to remain competitive on a budget."
The energy allowance will be used to balance the performance of different technologies without the need for the present system of restrictors.
FIA endurance commission president Lindsay Owen-Jones added: "Today the ACO and the FIA have announced a unique set of extremely innovative technical regulations for 2014 that are in phase with the times we live in.
"It should encourage the development of powerful and spectacular cars, and also the development of technologies that have real meaning for the everyday motorist."
In other rules adjustments, open-top LMP1 cars are now banned, and drivers' seating positions will be raised and windscreen sizes increased to improve visibility. The cars' width will also be reduced by 100mm, and wheel tethers and rear crash boxes will be introduced.