Energy efficiency improvement is generally viewed as the most important short-term CO₂ mitigation option. But even larger energy efficiency improvements are within reach in all economic sectors on the long term.

The technically feasible potential for energy efficiency improvement on the long term is a reduction of 50%-80% on specific energy consumption. In almost all sectors these improvements are possible. Some examples for energy efficiency improvement that illustrate this potential are:

• It is possible to build offices and dwellings that require hardly or even no energy for heating. Heat losses are reduced by insulation of walls and windows and almost all energy is provided by the users, appliances and the sun. However, an optimum has to be found, because the demand for cooling may increase. Developments of new materials and 'smart' windows as well as better designs are necessary.

• The energy efficiency improvement is also possible in the transport sector. At this moment there are cars (prototypes) which have a 50% higher efficiency compared to the existing efficiency of the average car fleet. On the long term even the one liter per 100 km car or the (netto) zero emission car are serious options.

• Household appliances are improving steadily. For instance, an average washing-machine in the EU uses 230 kWh/yr. The average new washing machine uses 170 kWh/yr. The most efficient washing-machine on the market uses only 140 kWh/yr, a reduction of 40%. By a further reduction of energy losses, for example by improved washing powder for lower temperatures, this energy demand can come down to about 70 kWh/yr.

• Industrial processes can be changed fundamentally and thereby improve energy efficiency dramatically. For example the specific energy consumption of wrapping paper is nowadays 5.5 GJ/ton. Changing to for example impulse drying can improve this to 2.2 GJ/ton, an energy saving of 60%.