Reactors provide energy to all ship devices. Each Reactor costs 150 to create.
Reactor is one of the most important parts of a ship. To choose the ideal reactor, take into consideration the other devices that you are planning to use. If the devices use small amounts of energy but very often, you will need a reactor with lower Maximum Load but with a lot of Power. Power-hungry devices that use more energy but less often (such as Artilleries or powerful Cannons) will benefit more from a less powerful reactor that has higher capacity. As a general rule, more Power is better.
If the ship uses up more energy than the reactor can provide (the Reactor Load indicator will go to red), the reactor will shut down, burst or explode. Shutting down will immobilize the ship, bursting will damage all devices on the ship, while an explosion will destroy the ship.