|● Energy resources|
|● End use efficiency|
|● Natural energy flows|
|● Environmental impacts|
|● The costs of energy|
|● Energy limits|
All energy technologies have some environmental impacts. To help in the process of selecting which technologies might be most important for a sustainable future, this chapter develops a set of environmental criteria and strategic guidelines. They concern specific local impacts as well as overall energy resource limits. The criteria that emerge form the basis of much of the subsequent analysis in this book.
As we have seen, a range of environmental and resource problems have emerged so far from the use of energy technology. Our review of these issues should have indicated some basic criteria for technologies which avoid or minimise the problems.
Let us assume that our 'technical' goal is to devise a set of energy technologies which can meet human needs on an indefinite basis without producing irreversible environmental effects.
From this simple definition of the technical requirement, it is clear that the technologies should not use fuel resources that are likely to be rapidly depleted. This is the first criterion, which is concerned not with environmental impact but with fuel reserves and resource availability.
Of course, all the existing fuels (coal, oil, gas and uranium) only exist in finite amounts on this planet and are not being replaced. The conditions