From energy-saving refrigerators, low-consumption automobiles, and intelligent building management systems to resource-saving production processes in industry, energy efficiency is a versatile topic that is - and will remain - of great importance in all areas of our everyday lives. Solar technologies are characterized as either passive or active depending on the way they capture, convert and distribute sunlight and enable solar energy to be harnessed at different levels around the world, mostly depending on the distance from the equator.

Typically these two technologies are used separately (or only placing them in parallel) to produce hot water 133 In this system the solar energy efficiency definition thermal panel performs the function of the low temperature heat source and the heat produced is used to feed the heat pump's evaporator.

In essence, the UK energy market will either see the energy price cap temporarily suspended so that energy suppliers can recover, which would mean that consumers end up paying the cost, or the energy price cap remains in place and energy suppliers that cannot survive the competition go bust.

Similarly, investing in energy efficiency is almost always cheaper and cleaner for utilities than new generation resources—or even the fuel costs of existing generation—but such investments lead to reduced earnings potential under the traditional utility business model.