Embodied Energy Analysis of New Zealand Power Generation Systems
Embodied energy is the energy consumed in all activities necessary to support a process in its entire lifecycle. For power generation systems, this includes the energy cost of raw material extraction, plant construction, operation and maintenance, and recycling and disposal. Embodied energy analysis is a crude method of estimating the environmental impacts and depletion of natural resources consequent to a certain process. In effect, the higher the embodied energy of a process, the greater the green house gas emissions and the depletion of natural resources. This paper presents the embodied energy analysis carried out on some New Zealand power plants belonging to various methods of generation. The analysis follows the standards set out by the International Organisation for Standardisation 14040 series, and uses some guidelines given in the International Federation of Institutes for Advanced Study workshop on energy analysis methodology and conventions. It was found that the lifecycle performance, in terms of energy payback, of renewable electricity generation is superior to nonrenewable electricity generation. From the generation methodologies, hydro power plants have exceptional performance characteristics.