Hydrogen is used as a cooling atmosphere in power plants across the globe because during operation, currents flowing through electric power generators produce large amounts of heat. This heat can potentially damage the generator casings, and result in efficiency losses. Additionally, heat-related effects limits the amount of electrical power that can flow through electric power generators. In order to control these losses, and maintain a high level of efficiency, high purity hydrogen must be made available at a consistent production rate. Even minor hydrogen contamination (occasionally caused by concentrations of air, water, oil vapor, or other substances) will increase windage friction losses in the generator.