Often in debate on energy matters the question arises as to whether a certain technology requires more energy for its manufacture than it will produce during its lifetime. Proponents of renewable energy technologies should be ready to answer such questions and be able to compare these technologies with fossil fuel technologies. Comparing technologies on present economic grounds would be very short-sighted as the growing environmental movement will demand other criteria to be used which will include damage to the environment. The study is only a preliminary one, pointing the way for a detailed follow-up study. In order to assess the energy required to manufacture, Install and operate a device, such as a solar hot water heater, it is necessary to identify all the individual components and processes associated with the system.
Difficulty arises in determining the energy required to manufacture a given component.
For example, the energy required to produce copper sheet varies greatly depending on the grade of ore used. Production of a particular product, such as copper sheet, can involve many processes. Actual analysis is seldom carried beyond order two, since further orders usually make an insignificant contribution to the overall energy consumption. In the analysis presented here we are interested in comparing the total life cycle energy required by a fossil fuel system with a renewable energy system to achieve the same task. Comparing the total life cycle energy required to provide hot water by electricity and solar energy.