Models of energy saving systems: the battlefield of environmental planning

Traditionally, energy planning has been interpreted as planning for an appropriate energy supply system, based on a crude prognosis for the energy demand. Over the past couple of decades, however, the immense possibilities of regulating energy demand - and the benefits of doing it - have become increasingly recognised and also partly included in the planning. This paper first describes some methods and concepts organised around the energy chain, and used in analysing energy savings options at the end-user. The end-use efficiency is by definition difficult to estimate, and this problem might very well contribute to the lack of success in implementing the savings. Various ways out of evaluating the results are discussed. End-use efficiency links the technology to the human needs and lifestyle, and hence energy saving research is interdisciplinary. The "efficiency" of the way people live in the future becomes a decisive factor in energy planning. Conflicts are described between sub-optimising for instance the supply system only and optimising the whole energy chain from means to ends. A number of examples illustrate how a one-sided focus on technical end-use efficiency can actually lead to higher energy consumption. This somehow illustrates the fundamental conflict between market economy and energy planning for an environmentally sustainable future, demonstrating the need to reach a balance through a properly regulated market. A basic planning process is outlined, based on the three main categories of demand determinants, namely population, standard of living, and technology applied. Finally are listed some flaws of past energy modelling as well as some visions of the future.