A 36-volt nickel metal hydride (NiMH) battery pack located under the load floor powers the motor/generator unit, and also stores regenerative braking energy.

During braking, energy, the regenerative braking energy, is captured in the lead-gel batteries and the ultracapacitors.

One focus consists in applications for regenerative energy and energy storage.

Likewise, the efficiency gauge in the upper left corner of the instrument panel indicates the most efficient braking range to capture regenerative braking energy.

Another improvement is to decouple the electric motor from the battery through electronic control, employing ultra-capacitors to buffer large but short power demands and regenerative braking energy.

You can also conserve energy by switching the blue-knobbed gear lever into "B", which produces more engine braking and regenerative energy.

Persuaded she will one day become River Song, in whom the Doctor places great trust, Melody chooses to resurrect the Doctor with her regenerative energy, losing the ability.

The ceramic brake discs can also provide regenerative braking energy.

They can also switch regenerative braking energy between vehicles and the electric grid rather than requiring energy storage on the vehicles.

The Doctor's companion, Donna, became part Time Lord after touching the Doctor's severed hand, which had regenerative energy locked within it.