The two manufacturers planning to race hybrid systems at this year's Le Mans 24 Hours, Audi and Toyota, want to see the technology become more widely available to customer teams in the future.
Audi has chosen to use a flywheel-based system while Toyota's new TS030 harnesses energy derived from super-capacitors, both of which allow these teams access to 500kj of energy between braking phases, when the energy is stored.
But the technology remains in its infancy in endurance racing and, according to Toyota's team president Yoshiaki Kinoshita, it remains prohibitively expensive for non-manufacturer teams at this stage.
"It is one of our aims [to provide hybrid to customers]," he said. "But the current situation is that this system is not so cheap, so it may take another three or four years until we can provide our system to the customers – but for sure, we want to."
Audi's motorsport chief Wolfgang Ullrich added that the working group put together to define the 2014 regulations had taken into account customer teams when structuring the new framework for efficiency-related technologies.
"The group that has been working together to develop this rulebook had for sure in mind this issue," he said. "And we have to find a solution and we are trying to find one. But if you want to push completely new technologies into racing then for sure at the very beginning only manufacturers will be able to do that, but what you don't want to do is close the door."
Ullrich added that he believed the rules would move toward a less restrictive use of hybrid technology after 2014, which would allow manufacturers to further explore the potential of the systems.
"The idea is that the most efficient car will be the one that has the best chances to run and I think that's the right way, because that is the same way that is relevant for our road cars. The ACO and the FIA leave [the door] in a certain way open, so future-oriented technology should have a chance to show up in racing, improve the abilities, and I think this has always been a good motivation to use this later on for the road cars."
Kinoshita said that he believed Toyota's system was already capable of producing double the power it is allowed to employ within the current regulations.
"Theoretically speaking, we can recover twice as much energy, by our calculations, so if there is no limitation to recover the maximum energy we can do much more with our hybrid systems," he said. "So I clearly hope we can recover more energy in the future."