General Motors and Honda have begun shipping fuel cell power systems to customers from a factory near Detroit, they said on Thursday, a new test of whether hydrogen power technology can achieve mass-market success.

Initial production of fuel cell power units will be relatively small, with Honda executive Jay Joseph saying at an event on Wednesday that his company is aiming to deliver 2,000 fuel cell power units annually by the middle of this decade.

Honda will use fuel cells in a version of its popular CR-V sport utility vehicle due to be unveiled in March, and Joseph said they will also be included in other products including stationary power generators.