The KERS system could make a return to the F1 grid for the 2011 season after it was revealed that work is ongoing on cheaper and more powerful versions of the energy recovery system.

KERS was introduced into the sport last season but teams agreed to shelve the technology this year due to the costs involved.

However, Williams F1 technical director Sam Michael has now revealed that both Renault and Ferrari have offered to supply KERS at an affordable level with teams now left to decide on whether or not to bring the technology back.

"Basically, Ferrari and Renault put forward proposals that they could do KERS for less than a million euros," he told Reuters following a meeting of the Formula One Teams' Association. "Those have been accepted but what Ferrari and Renault are both saying is that unless we increase the energy level from the current 400 kilojoules up to 600 or 800, to make KERS more beneficial, they are not prepared at this stage to commit that they will actually do KERS.

"I think that by Barcelona, the FOTA executive is due to try and make a decision on KERS for 2011. It's all pretty split at the moment on that. Renault will supply anyone who asks for it on the grid and Ferrari will supply any of their customers, anyone who is running a Ferrari engine."

Should KERS be reintroduced, Williams would more than likely develop its own system after increasing its stake in Williams Hybrid Power from 40 to 78 per cent.