

There are some interesting proposals for electric ships using containerized batteries which can be loaded/unloaded with the same cranes they use for shipping containers and charged in port. https://cleantechnica.com/2025/05/24/beyond-the-harbor-electrifying-short-sea-routes-and-hybridizing-blue-water-shipping/
It may not be suitable for transoceanic trips but a lot of shipping follows the coasts or even travels by river where this may be more practical.
Editing to add this link from another comment because I had no idea that (of course) there’s organized opposition by entrenched interests to prevent anything for the public good https://www.motherjones.com/politics/2025/06/dark-roof-lobby-white-reflective-roofs-laws-lobbying-urban-heat-islands/
I don’t think the current roofs are painted black - they’re naturally black because roofing tar and asphalt shingles are black by default (a lot of sheet metal roofing is too but you can at least get that in most colors). So it’s not a matter of swapping out paint but adding something new. It also adds a new maintenance cost - keeping the white roof clean/maintained. Paint flakes off, tarps etc wear and become tattered, dirt and pollen collect on the surface. None of this is a dealbreaker by any means but our society seems to run on defaults and there’s a lot of inertia in construction and a lot of pressure on builders to keep materials costs down (even if doing so costs the owners or occupants more in the long run).
I hope this continues to take off because it really is a big improvement.