Template:Easy Aug-07

From Lauraibm

Full article: It's not easy being Green (7-Aug-07)

This is an overview article that covers many topic: data centre consolidation, wind and wave power, energy losses in transmisson, nuclear energy, CHP etc.

• Taking power from green energy suppliers seems reasonable—but what happens if all organisations and homes did this? There is nowhere near enough green power being produced.
• The greenest means of generating centralised power may yet appear to be nuclear—provided you are willing to disassociate the long term green costs of decommissioning from those of the actual power.
• Limits in the basic efficiencies of turning raw materials to electricity mean 60 per cent of possible energy is already lost before we get any electricity out of a power station that uses fossil fuels.
• The National Grid leads to further losses of nearly 8% of the remaining power through resistive heat dissipation, and further inefficiencies at substations and distribution to local points of usage account for yet more waste.
• Finally we get losses due to the inefficiencies of the electrical appliances themselves.
• Around 70% of energy having been lost before we get to use it, and we then waste more ourselves.
• IT is estimated to use 5% of all power and targets are set to bring this down to 4%.
• Heat generated from the data centre could be used elsewhere in the building, for example to heat or pre-heat water.
• If we could bring the power generation closer to the point of use, we could utilise the heat generated in the creation of electricity within the building's Heating, Ventilation and Air Conditioning requirements. Commonly known as combined heat and power (CHP), such units were considered during the 1990s but haven't made much impact as power utilities have chosen to go with the lower maintenance and running costs of centralised power plant.
• The transmission of gas has also become more efficient over time, with low losses. Gas powered CHP units can have overall efficiencies greater than 75 per cent, so we are more than doubling the base efficiency compared to large centralised electricity generation with no heat recovery.
• Another option is for businesses to run at a fixed load and sell excess electricity and heat to the National Grid and local community (a concept known as Community CHP, or CCHP). The solution therefore not only creates greener, more efficient electricity but removes or cuts heating costs and can provide revenues for organisations to boot.