Energy Efficiency Reduces Energy Losses - the Energy Demand Approaches Zero
thermos flask

The figure illustrates the basic principles of increased energy efficiency. It shows why energy efficiency can substitute energy:
The service needed here is to keep coffee hot. That can be done by consuming energy (right hand, hot plate), or by not allowing for heat losses from the beginning (left hand, thermos flask). A very small heat loss is still there, of course - but it is negligible. Therefore the hot plate can be left out completely.

The state of the art in marketable products for energy efficiency is underestimated regularly: A window used in passive houses saves some 70% of the heat loss of existing double pane glazings; a good additional insulation of an exterior wall can save almost 90%, and an efficient heat recovery unit 75 to 90% of the ventilation losses. Through such measures, the major part of the former energy consumption is no longer required. What small amount remains can be covered by several options. Even if conventional energy sources will be used, the situation will be fairly improved, because resources will last longer and environmental pollution is reduced.

More about the International Conference on Passive Houses 2007-April-13 to 15th:

CRT monitor and TFT monitor
Another example: Old CRT-monitor (left hand side) and energy efficient monitor (TFT); the electricity demand is reduced by 70% - while user comfort is increased.

The computer sector could do much more on an energy efficinet design of their products. It is possible to have the full service of a PC incl. monitor and peripherials using only 5 to10 Watts continuous power. This is shown by the project "One Laptop Per Child". We support this project - it is a contribution to the most important future task, to improve education worldwide. See this link for further information:

olpc - one laptop per child -

Energy efficiency does not require a compromise in occupant comfort - not at all. Using higher efficiency makes it possible to increase comfort while reducing energy consumption.

The passive house is a paradigm for this approach in the building sector. And the same principles can be utilised in other sectors as well: A car using just 1-Litre-gasoline per 100 km reduces consumption by 75 % (without loss in rider comfort), an LCD-monitor saves some 70 % of the electricity demand of CRT-monitors and compact fluorescent bulbs save 75 to 80% of the electric power needed by incandescent bulbs.

Energy efficiency: Energy consumption is reduced by more innovative and intelligent products and by intelligent process integration.
In most cases this needs some additional investment, but these are cost-effective as a rule. The products needed can be produced near the customer. This gives rise to employment and innovation.

Is efficiency just the same as the technical "efficiency factor"? Not at all, efficiency is a far wider concept - read more.

Article on energy efficiency for free download (492 kB) (German).

Wolfgang Feist  
Author: Dr. Wolfgang Feist

updated: 2006-11-06 WF - thanks to Peter Cox for proof reading
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