Searching a better way to improve battery life when compiling programs without a connected charger I’ve found Turbo Boost Switcher. This software instructs the CPU to work at it’s limited hardware clock and not taking advance of the extra juice offered by the turbo boost technology.
While on Linux or Windows this can be achieved very easily using the performance tuner for each Power Profile, on mac this is almost impossible with the onboard tools supplied by apple.
Attention while using this tool since it’s not an apple supplied software it may lead to unexpected system behaviour. This is highly unlikely to happen, but be careful.