This mod adds higher-performing versions of the nuclear reactor, heat exchanger, steam turbine, and offshore pump.
Here’s a table explaining the improvements:

Item Stats Comparison

Steam Turbine
Vanilla: 5.82 MW
MK2: 30 MW
MK3: 91 MW

Nuclear Reactor
Vanilla: 40 MW
MK2: 80 MW
MK3: N/A

Heat Exchanger
Vanilla: 103/s
MK2: 483/s
MK3: 600/s

Offshore Pump
Vanilla: 1200/s
MK2: 2406/s
MK3: N/A

Details:
The MK2 Reactor is 2× more powerful than vanilla, with a better neighbor bonus.
The Steam Turbine is 5× and 15× more powerful than vanilla, with improved efficiency.
The Heat Exchanger is 4.5× and 6× better but requires higher temperatures.
The Offshore Pump has double the pumping speed.