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Batteries have to contain all of the chemicals on both sides of their energy releasing equation. The very best batteries available today can store about 0.4 MJ/kg (0.05 kw-hr/lb) including the cases and safety systems. In contrast, gasoline carries about 46 MJ/kg (5.7 kw-hrs/lb).\n\nEven with a 20% efficient IC engine, a gasoline tank stores 20 times as much energy as a battery of equal weight. As the vehicle is moving it gets rid of some of that weight. Battery powered vehicles must carry the full weight of their energy source.\n\nThe energy density difference also plays a key role in the time that it takes to put more energy back on the vehicle once a fuel load is consumed. A two minute fill-up of a 12 gallon tank puts the equivalent of 87 kilowatt-hours into the vehicle, again, taking into account the 20% thermal efficiency.\n\n87 kilowatt-hours in 2 minutes works out to 2.6 MegaWatts. Even with a 220 volt connection, that would require about 11,800 amperes of current. Just imagine the size of the electric cables for that current.\n\nThere are certainly places and applications where electric vehicles have a role, but it is worth remembering that at least five or six generations of engineers have looked very hard at trying to meet transportation needs and they keep coming back to the same fact - when you want to move a vehicle, you need power, (energy per unit time).

While most US residents say they're concerned about their home energy costs, only a small number are willing to pay upfront to gain access to real-time and detailed information about their energy consumption, according to a new survey released today by Oracle.

I sympathise with these consumers. In Europe, I would guess the average utility bill not to be far from 200 euro per month, or 6-7 euro per day, and relatively stable. As a consumer, information on expenditure for food, transport and telecommunication might be as relevant, if not more.

...offshore wind is at least as much about offshore technologies as it is about wind technologies.

The paper itself is flawed suggesting that virtualisation can reeduce the number of servers required to 7% - enough to handle the average processing load. Webusers want instant reaction during the peak - for that you need spare capacity. Is this a surprise?

The Internet doesn't produce belching smokestacks or toxin-spewing drainpipes. Instead, the environmental impact of the data centers that power the Web and private networks is about as visible as the electrons moving around a company's servers. But visible or not, the ecological and economic costs of those servers are massive. A report released last week by the Environmental Protection Agency estimated that U.S. data centers (collections of computers used to power businesses' and government agencies' IT infrastructures and Web sites) consumed around 61 billion kilowatt-hours in 2006 at a cost of about $4.5 billion. That's about 1.5% of total U.S. electricity consumption, more than the electricity used by American televisions, or equivalent to the output of about 15 typical power plants

Europe's largest onshore wind farm is set to be officially switched on by Scottish First Minister Alex Salmond. David MacKay, professor of natural philosophy at the University of Cambridge's department of physics, said Whitelee was a step towards targets to cut carbon emissions, but was only a start. He said: "To achieve the government target of a complete decarbonisation of our electricity supply system by 2030 we need to be talking about a 100-fold increase in wind farms in Britain and perhaps as much as a five-fold increase in nuclear power. "That's the scale of the building challenge we have if we're serious about getting off fossil fuels."

Among the major culprits here are inefficient appliances. According to the United States Department of Energy, a gas burner delivers only 35 to 40 percent of its heat energy to the pan; a standard electrical element conveys about 70 percent. Anyone thinking about kitchen renovation should know that induction cooktops, which generate heat directly within the pan itself, are around 90 percent efficient.

Another one of these, but this time from a source who cares deeply about the environment, while ignoring economics.

The bad news: organisations in the UK are wasting as much as £300 million a year by keeping idle computers switched on at night, according to a report conducted by Harris Interactive® on behalf of 1E and the Alliance to Save Energy. The good news: British organisations are much better at conserving computer energy than are their counterparts in the US. Concerns about the environment inspire 27 percent of UK workers to power down their computers at the end of the workday, according to the report. In the US, only 10 percent cited such concerns. If all the 17 million computer-using workers in the UK would power down at night, they could reduce the nation's yearly carbon dioxide emissions by about 1.3 million tonnes - about as much as is produced by 245,000 cars.

Normally these academics would be fine without our fascination. They weren't looking for glory when they decided to study organisms most people either can't see or wish they hadn't. But when the Deepwater Horizon exploded in April 2010, our collective bias toward cute big creatures started to matter a great deal. That's because the instant the spill-cam was switched off and it became clear that there would be no immediate mass die-offs among dolphins and pelicans, at least not on the scale of theExxon Valdez spill deaths, most of us were pretty much on to the next telegenic disaster. (Chilean miners down a hole-and they've got video diaries? Tell us more!)

I want to share with you some of the things that have made me excited about the future of clean energy. I hope you'll find them as cool as I do! See it on Scoop.it, via Sustainable Energy via scoop.it

Back in April, President Obama signed the JOBS Act and one of the most-heralded elements was so-called crowdfunding. The law sought to solve a major problem: it's hard to finance small-scale business ventures. Wall Street only cares about multi-m...