This is the Nissan NISMO entry to the 2015 Le Mans 24 Hour race, the GT-R LM NISMO.
The GT-R LM NISMO is a front-engined, front wheel drive car that is powered by a V6 3-litre twin turbo petrol engine and a kinetic energy recovery system- It is the ultimate GT-R.
Some info on the Nissan LMP1:
Nissan has yet to announce how retrieved energy is stored, but it is understood that it is a flywheel system.