Economies of scale meant that it made sense to centralise energy production.

Environmental groups have long opposed using trees for biomass energy production.

The most efficient form of energy production within the body is the metabolism of food.

The President, backed by trusted advisers, some of them dyed-in-the-wool oilmen, called immediately for increased energy production.

The whole process of energy production and use in the body can be compared with the working of a motor car engine.