Hydrogen fuel cells transform the coal-era fleet

What changes if practical hydrogen fuel cells become available for warships by 1895?

Cleaner ships and domestic hydrogen production would change propulsion and logistics, with infrastructure investment becoming a major constraint.

Practical hydrogen fuel cells by 1895 would remove coal soot and much of the propulsion variation caused by different coal grades. Their water byproduct would also provide fresh water aboard ship. States could produce hydrogen using poor-quality coal or hydroelectric power, provided they built and maintained the necessary infrastructure. Investment in fuel production would therefore matter more than access to particular coal or oil supplies. Ships would need protection against shock, and the technology would also change submarine design. The scale of these consequences makes a detailed reconstruction of the resulting fleets difficult.