> AIPs are a big competitor to replace diesel submarines
AIP is a supplementary system used by diesel submarines, not a replacement for them. They don't have sufficient power for anything but slow quiet cruising. AIP equipped subs will retain diesel generators for faster sprints, and greater endurance while transiting on the surface or via snorkel.
The two basic technologies for AIP are fuel cells and sterling engines. Both are deployed successfully at the moment. The video above is a neat summary of a 2nd generation fuel cell system that uses an onboard reformer to generate H2 from diesel, avoiding the downsides of H2 storage.
AIP is a supplementary system used by diesel submarines, not a replacement for them. They don't have sufficient power for anything but slow quiet cruising. AIP equipped subs will retain diesel generators for faster sprints, and greater endurance while transiting on the surface or via snorkel.
The two basic technologies for AIP are fuel cells and sterling engines. Both are deployed successfully at the moment. The video above is a neat summary of a 2nd generation fuel cell system that uses an onboard reformer to generate H2 from diesel, avoiding the downsides of H2 storage.