An energy well produces energy namely, but is rarely used as a major source of energy despite it's high level of efficiency. The energy produced is incredibly low in comparison of a nebula plant. It needs to be located on energy, making running food, water, and energy to and from it to a planet hard and inconvenient. It does however provide a shield battery for pilots to recharge their shields at a price and for no wait, but the battery has a limited amount of charge which can be increased by upgrading the production. An Energy well is a low level building.