There are a million efficient ways to make heat and tons of new development to be made in making heat in new ways. There is relatively very little development in turning heat into kinetic energy and then electricity when size and weight are no object. The combined cycle turbine is incredibly efficient and is likely to continue to be ubiquitous in power generation for some time.

Seaweed is a type of macroalgae. It’s debatable if algae count as plants or not, they are photosynthetic but are in many ways their own weird form of single celled organism

Seaweeds aren’t even plants…