Who goes first, the chicken or the egg?

In discussions about global warming, many are reluctant to make 'the first move'. The coal industry points at figures by the Energy Information Administration (EIA), showing that coal accounted for 'only' 39% of the world total carbon dioxide emissions in 2004, while emissions from oil were larger. In reply, the oil industry points at EIA projections that coal looks set to become the largest energy source by 2010.

The car industry uses similar tactics, when asked why they don't offer more electric cars. They will respond that most electricity is generated by burning fossil fuel. For the record, electric cars do cause less greenhouse gas emissions, even when the electricity to power them was produced by coal-fired power plants.



Procrastinators hang on to all kinds of rhetoric in efforts to postpone making the necessary changes. It often comes down not to who goes first, but to 'What comes first, the chicken or the egg?' But of course, it doesn't matter who emits more, or who takes the first step, because both the chicken and the egg will have to change their act.

Another example is industrial use of coal. Coal consumption is projected to more than double in China and India by 2030, according to projections by the Energy Information Administration. While most of this coal will be used by power plants, a substantial part of coal in China is projected to be used in the industrial sector, as also pictured in the main image at the top. China was the world's leading producer of both steel and pig iron in 2004.

China is reluctant to switch to electric arc furnaces in its metal industries, believing it to be more efficient to burn coal directly in blast furnaces, rather than to burn coal in power plants first and then bring the energy to electric arc furnaces. But since global warming makes it necessary to shift from fossil fuel to electricity, it does make a lot of sense to shift from the traditional blast furnaces to electric arc furnaces. And if you look at the rising prices of fossil fuel, it also makes a lot of economic sense to shift to alternative ways to produce electricity.

How much land does it take to shift to solar energy? In one paper, Ausra estimates that concentrated thermal power facilities could power the entire US grid – day and night - and would fit in a square area of land with as little as 92 miles long sides. This corresponds to less than 10% of the Federal land in the state of Nevada and it is readily available without deminishing other land usage.

In a second paper with more conservative estimates, Ausra calculates that its solar facilities with stored energy in molten salt could cater for most US day-and-night electricity needs, and would theoretically fit inside a square with 153km sides. To additionally accommodate an entirely electrified vehicle fleet, the land area would grow to a square with sides of not more than 211km.

The cost of solar thermal energy? Ausra's 2007 discussion paper speaks of 10 cents per kWh now, under 8 cents per kWh in 3 years time. This 2006 report in Treehugger describes an agreement between Stirling Energy and Southern California Edison to construct a 4,500-acre 500-MW solar generating station in Southern California, 70 miles northeast of Los Angeles, capable of producing electricity at a cost of 6 cents per kWh.

Meanwhile, the price of photo-voltaic solar panels has come down dramatically with the introduction of thin film technology. Nanosolar promises to produce electricity even cheaper, due to low production cost. According to this article in Popular Science, the Nanosolar's cells use no silicon, and the company's manufacturing process allows it to create cells that are as efficient as most commercial cells for as little as 30 cents a watt, which would make it cheaper than coal, but without the pollution of coal. Also, solar panels on the roofs of houses, offices and car parks would not require extra land, and could power the respective buildings directly, thus competing with end-user prices, rather than wholesale prices.

Of course, even when adding molten salt storage, as offered by Ausra, it's hard for solar power to cater for peak demand during cold winter evenings, which makes it expensive to rely solely on solar energy. Therefore, it makes sense to complement solar energy with wind energy, hydro energy, geothermal energy, etc, to achieve a mix that is both most effective and financially attractive. Electricity can be transported nationwide over high voltage direct current (HVDC) lines, with line losses of about 3% per 1000 kilometers (620 miles), adding $0.01 - $0.02/kwh to the local price of electricity, making import of electricity from interstate another alternative to consider for a local area.

Wind turbines have a tremendous potential. One evaluation estimates that wind turbines can potentially generate 72 TW, or over fifteen times the world's current energy use and 40 times the world's current electricity use. Even if only ~20% of this power could be captured, it could satisfy 100% of the world's energy demand for all purposes (6995-10177 Mtoe) and over seven times the world's electricity needs (1.6-1.8 TW). Wind power currently costs between 4 and 6 cents per kWh.

A 2006 MIT study estimated the extractable portion of geothermal energy in the United States to exceed 200,000 EJ or about 2,000 times the annual consumption of primary energy in the United States in 2005. With technology improvements, the economically extractable amount of useful energy could increase by a factor of 10 or more, thus making extraction sustainable for centuries. About 42 GWe could be available by 2011 at a cost of less than 10¢/kWh if drilling cost improvements and technology improvements continue to be made.

Just like we shouldn't rely on any single source of power (wind, hydro, solar power, geothermal, wave, tide and more), we shouldn't rely on a single way of storing power either. Apart from using car batteries for storage, we can think of capacitors, hydrogen, fly-wheels, compressed air, steam, sodium, molten salt, pumped-up water, etc. Clocks in the old days used springs or weights to store energy. Similarly, bricks could be used as weights in larger contraptions. At even larger scale, we could use the Great Lakes as a reservoir not only of water, but also of energy. At times of peak supply of wind and solar power, surplus power could be used to pump water back from a lower to a higher lake, in order to use hydro-power at times when supply of other types of power is low.

There is an abundance of energy that already now is price-competitive with fossil fuel, depending on local conditions. This realization should lead to a global commitment to reduce emissions, by urging local areas to each implement policies that discourage emissions and that at the same time support better alternatives. Feebates can be taylored to achieve this most effectively. Such policies don't need to select specific alternative technologies; they merely need to insist that alternatives be safe and clean; market mechanisms can further sort out what works best where.


References:
http://www.eia.doe.gov/oiaf/ieo/coal.html - Energy Information Administration
http://www.sciam.com/article.cfm?id=a-solar-grand-plan - A Solar Grand Plan http://www.ausra.com/pdfs/SolarThermal101_final.pdf - Ausra paper 1
http://ausra.com/pdfs/ausra_usgridsupply.pdf - Ausra paper 2
http://ausra.com/pdfs/070820discussion.pdf - Ausra discussion paper
http://www.stanford.edu/group/efmh/winds/global_winds.html - Global wind power
http://www.nrel.gov/wind/advanced_technology.html - National Renewable Energy Lab
http://geothermal.inel.gov/publications/future_of_geothermal_energy.pdf - The Future of Geothermal Energy - Massachusetts Institute of Technology (MIT)