Showing posts with the label Energy efficiency

Energy efficiency

During energy transformations, energy can neither be created nor destroyed. However energy can be degraded, that is there is less useful energy after the change than there was before. This is because some of the original energy has been changed into heat or sound and lost to the surroundings. General and credit level equations Useful equations for energy calculations in power stations include: gravitational potential: Ep = mgh kinetic energy: Ek ½mv 2  (credit level only) electrical power: P=IV also, for all forms of energy: E=Pt Calculating efficiency (credit level only) The percentage of total energy output compared to the total input energy is its energy efficiency