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Over time, what resulted from these assessments was that we selected the following sources to provide commercial electricity: hydroelectric, coal, nuclear, natural gas, and oil. (Oil is by far the smallest source.) Note that each of these current sources meet ALL of the above six essential criteria — and if they don’t (like oil recently becoming more expensive), then they get replaced, by other conventional sources that do. As a result, today, and a hundred years from now, these sources can provide ALL of the electrical needs of our society — and continue to meet all six criteria. So what’s the problem? A new criteria has been recently added to the list of criteria: environmental impact — and the current number one environmental impact consideration is greenhouse gas emissions (e.g. CO2). So why has this joined the Big Six? It is a direct result of the current debate on global warming. In response to intense political pressure, governments have acquiesced to these forces to make emissions an additional criterion. Having government step in and mandate that utility companies change the principles that have been the foundation of our electrical supply system for a hundred years is disconcerting, transforming such a successful system based on a position that is not yet scientifically resolved. Furthermore, this new criteria for electrical supply sources now has taken priority over all the other six. It has, as of late, become the ONLY benchmark of importance — the other six have essentially been put aside, and are now given only lip service. In this unraveling of sensibility there is one final incredible insult to science: alternative sources of commercial electricity that claim to meet this new super-criteria (to make a consequential impact on CO2 reduction) don’t even have to prove that they actually do it! Let's look at the environmental poster child: wind power, and examine each of the six time-tested criteria, then the new one...

This summer Alcoa will test a new way of making the solar troughs used to make concentrated solar power (CSP) that could reduce the cost by 20%.

This is why Highview has been testing its 300-kilowatt pilot plant for the past nine months, supplying electricity to the UK's National Grid. The process stores excess energy at times of low demand by using it to cool air to around -190 °C. Excess electricity powers refrigerators that chill the air, and the resulting liquid air, or cryogen, is then stored in a tank at ambient pressure (1 bar). When electricity is needed, the cryogen is subjected to a pressure of 70 bars and warmed in a heat exchanger. This produces a high-pressure gas that drives a turbine to generate electricity. The cold air emerging from the turbine is captured and reused to make more cryogen. Using ambient heat to warm it, the process recovers around 50 per cent of the electricity that is fed in, says Highview's chief executive Gareth Brett. The efficiency rises to around 70 per cent if you harness waste heat from a nearby industrial or power plant to heat the cryogen to a higher than ambient temperature, which increases the turbine's force, he says. Unlike pumped-storage hydropower, which requires large reservoirs, the cryogen plants can be located anywhere, says Brett. Batteries under development in Japan have efficiencies of around 80 to 90 per cent, but cost around $4000 per kilowatt of generating capacity. Cryogenic storage would cost just $1000 per kilowatt because it requires fewer expensive materials, claims Brett.

Household appliances like washer-driers, ovens and light bulbs are not all living up to their energy efficiency labels, according to tests carried out by UK Government department Defra.

The researchers there have developed a system that is simpler to assemble and manufacture, and laid out their suggestion in a paper (pdf) presented at the 2008 European Wind Energy Conference. Till now; the blades of wind turbines have been connected to a generator via a gearbox. Their technology substituted a “C” shaped core generator (initially in a 20 kW prototype) to test to see if by changing the mechanical structure of the generator they could still maintain rigidity and structural integrity while cutting the weight by more than half. The design is simply a novel arrangement of the electromagnetically active components: the magnets, steel and copper inside the generator and the copper coils.