In December 2011, DECC published the Carbon Plan and version 3 of the 2050 Pathways Calculator.

As before, this open-source engineering-based tool is intended to support grown-up conversations about our possible energy futures. The user can choose any combination of demand-side and supply-side actions over the period to 2050, and the calculator computes and displays various consequences – energy flows, areas of land use, greenhouse gas emissions, and some security-of-supply indicators. The significant new feature in version 3 is the inclusion of costs, for the first time. Version 3 of the calculator also includes an air-quality calculator, which, like the costs calculator, is under development. Expert feedback is welcome.

The International Energy Agency is notoriously conservative on projections for renewable energy. The agency has embraced the need for more clean electricity and fuels to address climate change and peak oil, but its outlook for the future is usually far more conservative than how reality plays out.

So when an official at the IEA says we could get up to one third of our global energy supply from solar photovoltaics, concentrating solar power, and solar hot water by 2060, that’s a fairly big piece of news. But even that projection may be conservative.

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There is no easy way to cut the necessary emissions. We do need to be green, but it is not nearly as simple (or as cheap) as the greenies would have you believe. What is required are big changes in demand, and big changes in supply. We’re talking countrywide scales — hundreds of thousands of wind turbines, thousands of square kilometres of solar panels, massive cuts in demand, wholesale switches in technology, gigantic investments. You won’t hear these numbers from politicians, or not very often. Nor will you hear them from business leaders. And hardly ever from environmentalists.

Here are a few lamentable numbers to remember:

Every year our global civilization digs up, transports, heats and pummels and shapes and processes and sells half a trillion tons of materials. Only six per cent of all those tons ends up in products — the rest is used to mine and make and move them. And only one per cent — a single measly per cent — is still a useful product six months later.

Only 37 per cent of primary energy production is put to any real use. The rest is lost to conversion inefficiencies and waste.

About four-fifths of all energy used in transportation, including trains and planes, is spent on road traffic — and about half of that is for moving light vehicles and people. Worse, only about five per cent of the energy we expend in transportation actually gets us from one place to another. The rest is just to shift our inefficient internal combustion vehicles or is sent out the tailpipe as waste heat. Ninety-five per cent of the energy we use to get to Wal-Mart is wasted. So much for so-called “savings.”

The International Energy Agency estimates that somewhere around $45 trillion, or an average of one per cent of annual global economic output, needs to be invested between now and 2050 to make any real difference — which sounds unlikely in this era of “jobless recoveries” and multiple fiscal crises.

“Nearly all the energy we use on this planet starts out as sunlight that plants use to knit chemical bonds. Now, for the first time, researchers at the Massachusetts Institute of Technology have created a potentially cheap, practical artificial leaf that does much the same thing—providing a vast source of energy that’s easy to tap. The new device is a silicon wafer about the shape and size of a playing card coated on either side with two different catalysts. The silicon absorbs sunlight and passes that energy to the catalysts to split water into molecules of hydrogen and oxygen. Hydrogen is a fuel that can be either burned or used in a fuel cell to create electricity, reforming water in either case. This means that in theory, anyone with access to water can use it to create a cheap, clean, and available source of fuel.”

Even if your artificial leaf is 100% efficient at turning sunlight into electricity, you would need to cover an enormous area with them to meet today’s energy demand.

Most journalists seem to have no appreciation for scale, when it comes to energy. Yes, you can make biofuel out of discarded fry-cooking oil from fast food restaurants, but that isn’t a technology that scales cheaply to replace gasoline…

100 Percent Renewables by 2030?
By KATE GALBRAITH

Could the world get to 100 percent renewable energy by 2030? Not a chance, say most analysts.

But in an article last month in Scientific American, two California academics outline a path to this amount through “millions of wind turbines, water machines and solar installations.”

The paper, by Mark Jacobson, a professor of civil and environmental engineering at Stanford University, and Mark Delucchi, a research scientist at the Institute of Transportation Studies at the University of California, Davis, envisions 3.8 million large wind turbines, accounting for just over half of electricity demand in 2030. These would be augmented by 90,000 solar plants and other renewable technologies like tidal and geothermal power.

The turbines “would occupy about 1 percent of the earth’s land, but the empty space among turbines could be used for agriculture or ranching or as open land or ocean,” the paper states. Solar plants (not counting rooftop installations) would take up 0.33 percent of the earth’s land.