Steam reforming of methane from natural gas to product hydrogen is in fact very efficient (up to ~85% iirc). It is not, however, carbon-neutral. At a system level, the weak point is the fuel cell and they can be about 50% efficient. So you have an overall efficiency of a little over 40%.
Batteries can be very efficient but that is not an apples-to-apples comparison. You have to get the energy somewhere. Good solar systems are about 30% efficient. Turbines are about 30% efficient.
Energy efficiency isn't the problem with hydrogen and fuel cells. They have other problems.
Batteries can be very efficient but that is not an apples-to-apples comparison. You have to get the energy somewhere. Good solar systems are about 30% efficient. Turbines are about 30% efficient.
Energy efficiency isn't the problem with hydrogen and fuel cells. They have other problems.