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Alternative energy = not good enough

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Alternative energy = not good enough

Post  Roi on Fri Apr 05, 2013 12:07 pm

http://www.slate.com/articles/technology/future_tense/2011/10/oil_and_gas_won_t_be_replaced_by_alternative_energies_anytime_so.single.html

A dominant environmental issue of the last decade = climate change and what—if anything—the countries of the world can do to limit, or reduce, carbon dioxide emissions.

Since 2000, global carbon dioxide emissions rose by 28.5 percent to some 33 billion tons. By 2030, the International Energy Agency expects global carbon dioxide emissions to rise by another 21 percent to about 40 billion tons.
Carbon dioxide emissions will continue rising because hundreds of millions of people in places like Vietnam, Malaysia, and South Korea—and, of course, China and India—are transitioning to a modern lifestyle, complete with cars, TVs, and other manufactured goods. As they do so, they are using more energy. Specifically, they are using more hydrocarbons—coal, oil, and natural gas. And while lots of idealistic environmentalists and some policymakers argue that we should quit using carbon-based fuels and move to a global economy powered by nothing but renewable energy, the hard reality is that hydrocarbons are here to stay. Why?

1. Cost

The global energy sector is by far the world’s biggest industry, with more than $5 trillion per year spent finding, refining, and delivering energy of various forms to consumers. Renewable sources like wind and solar have their virtues, but they cannot compare with hydrocarbons when it comes to economics. A recent analysis by the Energy Information Administration estimates that wind-generated electricity from onshore wind turbines costs $97 per megawatt-hour. That’s about 50 percent more than the same amount of electricity generated by natural gas, which the EIA estimates costs $63. Offshore wind is even more expensive, coming in at $243 per megawatt hour. The least-expensive form of solar-generated electricity—the type generated by photovoltaic panels—costs $210, or more than three times as much as the juice produced by burning natural gas. If renewable sources of energy were dramatically cheaper than hydrocarbons, then perhaps we could be more optimistic about their ability to capture a larger part of the global energy mix. But even if that were true, a wholesale change in our energy mix will take a long time.

2. Slow pace of energy transitions,

For 109 years after the signing of the Declaration of Independence, wood was the dominant source of energy in America. It wasn’t until 1885—the year that Grover Cleveland was first sworn in as president—that coal finally surpassed wood as the largest source of energy in the United States Look at the oil’s share of U.S. primary energy consumption. According to the EIA, in 1949, oil provided 37 percent of America’s total energy needs. In 2009, oil’s share of U.S. primary energy stood at 37 percent. Over the past six decades, uncounted billions of dollars have been spent on efforts to reduce our need for oil, yet petroleum has been remarkably persistent. Conspiracy theorists will, of course, blame Big Oil. But the conspiracy wasn’t hatched in Houston or Detroit. It’s a conspiracy of basic physics.
If petroleum didn’t exist, we’d have to invent it. Nothing else comes close to oil when it comes to energy density, ease of handling, flexibility, convenience, cost, or scale. Electric vehicles may be the celebrity car du jour, but modern batteries are only slightly better than the ones that Thomas Edison developed. Gasoline has 80 times the energy density of the best lithium ion batteries.
Believe it or not, in 2009, renewable energy sources had a smaller share of U.S. primary energy than they did back in 1949. Sure, wind and solar have grown dramatically in recent years, but in 1949, renewables—almost all of it hydropower—provided 9.3 percent of the country’s energy needs. In 2009, renewables—again, much of it supplied by hydropower—provided 8.2 percent of U.S. energy.

3. Scale.

We use a lot of units to measure energy: Oil is sold in barrels, tons, gallons, and liters. Natural gas is measured and sold in cubic meters, millions of Btus, therms, dekatherms, and cubic feet. Coal comes in long tons and short tons, but its pricing depends on myriad other factors, including heat content, ash content, sulfur content, and most important: the distance between the coal mine and the power plant. Electricity is sold in kilowatt-hours but electricity terminology spans other units like volts, amperes, and ohms. Add in joules, watts, ergs, calories, and Btus, and things get even more complicated.
We need a simpler measure for global energy use, which now totals about 241 million barrels of oil equivalent per day. That sum is almost impossible to comprehend, but try thinking of it this way: It’s approximately equal to the total daily oil output of 29 Saudi Arabias. (Since 1970, Saudi Arabia’s oil production has averaged 8.2 million barrels per day.) And of those 29 Saudi Arabias, 25—about 210 million barrels of oil equivalent—come from hydrocarbons.
Furthermore, over the past decade alone, global energy consumption has increased by about 27 percent, or six Saudi Arabias. Nearly all of that new energy came from hydrocarbons.
Scientists and policymakers can claim that carbon dioxide is bad. We can talk about wind, solar, geothermal, hydrogen, and lots of other forms of energy production. But the question that too few people are willing to ask is this one: Where, how, will we find the energy equivalent of 25 Saudi Arabias and have it all be carbon-free?
The hard reality is that we won’t. The Saudis have invested hundreds of billions of dollars over the past few decades drilling wells and building their infrastructure so that they can remain the world’s most important oil exporter. And remember that all of those billions invested have given them exactly one Saudi Arabia, or about 3.4 percent of total global energy demand.

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There is no urgency for an accelerated shift to a non-fossil fuel world: the supply of fossil fuels is adequate for generations to come; new energies are not qualitatively superior; and their production will not be substantially cheaper.”

The United States now sits atop galaxies of low-cost gas that can be recovered from shale. In April, the Potential Gas Committee, a nonprofit group consisting of academics as well as representatives from government and industry, estimated U.S. gas resources at about 2,170 trillion cubic feet. At current rates of consumption, the United States likely has enough natural gas to last 90 years or more.

Renewables will remain niche players in the global energy mix for decades to come. The past—and the foreseeable future—still belong to hydrocarbons. And we can expect natural gas, the cleanest of the hydrocarbons, to garner a bigger share of the global energy pie in the near term and in the long term.


Roi

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Join date : 2012-11-19

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