There was this guy that made a pumped hydro water tank on his roof and by his calculations a cubic meter of water was equivalent to a AA battery.

That sounds crazy. Let’s do some math. From what I can find, a double A battery contains about 10-14 kilojoules of energy. Let’s use 14 to be charitable.

A cubic meter of water weighs about 1000kg. We know the formula for potential gravitational energy U = mgh. So if we used all the energy from the battery, we could lift the water:

14000 = 1000 * 9.81 * h
h = 14000 / (1000 * 9.81) ≈ 1.43 meters (4 feet 8 inches)

That assumes 100% efficiency of course. Still, lifting a ton of water even two feet ain’t nothing to sneeze at. Batteries have a lot of energy.

China leads the world in both renewable energy usage AND coal use. And by a lot.

They also have some of the most people (is India ahead nowadays? I can’t keep track), and they manufacture tons of things meant for export to other (including western) countries.

The point being, everybody is greenwashing. China is greenwashing their energy mix. Western countries greenwash their own energy by essentially outsourcing the production and thus pollution. And this isn’t about China really. I could say the same for a bunch of countries.

The small consolation is that beside all the green propaganda, some progress is at least being made. Probably not enough, but some.

BOOM! EVs win!

Is this a real headline? Of a news article? Was that part really necessary?

Highly optimistic. For one, the specific parameters of the core dictate the shape, size and configuration of all of the apparatus around it. You can’t just slot in a different heat generator and call it good to go. Secondly, there’s no guarantee that your future fusion reactor core even fits in the footprint of your fission plant. You have no idea what size and shape it will take.

Finally, your assertion is incorrect. Steam turbines, heat exchangers, and cooling towers are comparatively simple, low risk, and well understood parts of a nuclear reactor. The safety features, checks, design reviews, bureaucracy and permitting surrounding the core itself are what take the most time. Any part that could lead to radioactive containment breach.

You need to put this in perspective. Solar and wind waste streams are bigger than nuclear, but much, much smaller than coal and completely insignificant compared to regular old municipal waste.

If you switch from coal to solar right now you will save much more waste than waiting a decade for a nuclear plant to come online. Even if you start building the nuclear plant now, you will still save waste by building solar and throwing it in the trash once your nuclear is online. Anything to switch away from coal faster.

Retrofitting a nuclear fission plant for fusion? There’s no way that’s even remotely feasible, the two are radically different in construction.