Alternative energy is an umbrella term that refers to any source of usable energy intended to replace fuel sources without the undesired consequences of the replaced fuels. The planet Sera has always had an energy crisis. The use of petroleum, solar panels and nuclear fuels could never satisfy the energy stricken people. None of Sera's hydrocarbon (oil) energy resources could provide the resources that the power plants needed, until Imulsion was discovered, ironically by an Oil-exploitation drill, which lead to the "Gold Rush" period and ended the "Era of Silence". The biggest example of Imulsion taking over the market was when solar powered car sales dropped in favor of Imulsion powered cars.