Thursday, April 26, 2007

Global Warming: Limits of Solar and Wind Power

Contributed by: arch_stantonViews: 474
As people across the US poured into Earth Day celebrations, they saw booths and heard speakers extolling the virtues of solar and wind power. What participants were highly unlikely to hear was that renewable energy cannot stop global warming without major social changes that Earth Day organizers rarely discussed.Global Warming: Limits of Solar and Wind Powerby Don FitzZMagAs people across the US poured into Earth Day celebrations, they saw booths and heard speakers extolling the virtues of solar and wind power.

What participants were highly unlikely to hear was that renewable energy cannot stop global warming without major social changes that Earth Day organizers rarely discussed.Keep in mind the difference between the words “necessary” and “sufficient.”

Yes, expansion of solar and wind power is absolutely necessary to prevent CO2 levels from rising, coastal cities from being flooded and species from going extinct. But no, by themselves, solar and wind are not sufficient to make the use of energy sustainable.

Nine million percent?Most climate experts accept that, in order to avoid catastrophic effects of global warming, greenhouse gas emissions (mostly CO2) must be cut by 60-80% by 2050 (though the figure may need to be a 95% cut in the US).

The belief that replacing fossil fuels with solar and wind technology can accomplish this reduction tends to overlook several factors:1. Corporations bombard the world with the message that everyone should consume like Americans do;2. Corporations tell those in the US that they should ape after the playthings of the rich;3. Population is growing;4. Market economics force pathological expansion; and,5. Solar and wind comprise a minute fraction of current energy.

Let’s combine these to get an idea of how much solar and wind would need to expand to replace coal, oil, nukes and gas by 2050.

First, the US consumes about 25% of the world’s energy while having only 5% of the world’s population. For the rest of the world to consume at the rate of the US would require global production to increase by a factor of 6.33.People in the US constantly hear the message that they do not consume nearly enough.

The rest of the world does see skid row as their model for consumption — they also look at the wealthiest in the US. If we use the 5% wealthiest for the standard of comparison, the value of 6.33 should be squared to give 40.0 as the amount that world production would have to increase for everyone to consume at the level of the most affluent in the US.Population is expected to slow down its growth rate but still increase by 50% between 2007 and 2050.

Allowing for population growth, by 2050, production would need to increase by a factor of 40 x 1.5 = 60.The market economy must grow or die. A widely held view is that the world economy will continue to grow 2-3% annually during the rest of the century. A 2.5% growth rate would result in almost tripling production by 2050.

This means that production would need to grow by 60 x 3 = 180.During that time, solar and wind would need to replace other energy sources. According to the US Energy Information Administration, renewable energy accounted for 6% of all 2003 energy, and of that 6%, only 1% was from solar and 2% from wind (the rest coming from biomass, geothermal and hydroelectric).

This means that solar and wind comprise .06 x (.01 + .02) = .0018 of US energy. Accounting for less than 0.2% of energy, solar and wind would have to increase by a factor of over 500 to replace other energy. Multiplying the 500-fold increase in solar/wind by the 180-fold increase in production means that energy from solar/wind would have to increase by a factor of 90,000 by 2050 for people throughout the world to consume at the rate of the richest 5% in the US.If there is no challenge to the US being a model of consumerism, there would need to be a roughly nine million percent increase in solar/wind power for them to replace other forms of energy in 43 years.

No silver bulletSuch an increase is not likely to happen. One of the problems with figuring out what renewables can actually do is that those who are religiously devoted to them are prone to saying things that are out of touch with reality. In his new book, Heat, George Monbiot quotes a solar power enthusiast who wrote, “Even in the cloudy United Kingdom, more electricity than the nation currently uses could be generated by putting PV [photovoltaic solar power] roof tiles on all suitable roofs.” (p. 125) Monbiot put some numbers together and calculated that the actual potential for rooftop PV is 1/800 of energy that is used in the UK.Rooftop collection is a major component of a solar power strategy. A single story home would be most efficient. Unfortunately, this contradicts another principle of saving energy: the larger the building, the more self-insulating it is.

Multi-family apartments or condos need less energy to heat a room than would be needed in stand-alone homes of the same size. Similarly with putting solar panels on the sides of buildings. A building which is not surrounded by trees or other buildings would be great for such solar panels.

But trees are necessary both for shade and for taking CO2 out of the atmosphere. Putting multi-story buildings close to each other is necessary for the high density required by an urban mass transit system, but it works against the sun-catching surface space for solar collection.With about half of US energy going to temperature control for buildings, these factors limit the amount of energy that solar power can provide in urban areas.

PV technology works best for rural homes. The main problem that stand-alone systems must deal with is energy storage for times when the sun isn’t shining. A bank of batteries can cost over $20,000. It’s less costly if users can link their panels to a power grid and sell excess power to the local electric company. But if customers sell PV power to the grid, they will be doing so at hours when demand and therefore prices are low and buying power back when demand and prices are high.The price of solar power is falling, but it would need to plummet to replace fossil fuels. Though it takes 25-35 years for PV cells to pay for themselves, their life expectancy is only 25 to 30 years. Wind power has its own limitations.

It is only possible for wind to produce large amounts of electricity if it consistently blows strong. Since urban buildings tend to make wind weak or sporadic, wind mills are of little use in cities. Winds are usually strongest in mountain passes and along coastlines.A rapid expansion of wind power would involve far more than just the windmills themselves.

It would require new grid capacity and transmission lines from wind farms to locations of usage. Wind power requires 1.1 years of use to generate as much energy as used in manufacture and the figure for solar is 2 – 4 years. Are renewables truly renewable?Renewables are thought of as sources of energy that are not “drawn down” by their use. But this does not take into account materials that are used to harness the energy or their environmental effects. If the source of energy is infinite, but the land and materials that people use to capture the energy is not infinite, is that type of energy truly “renewable?”

The American Solar Energy Society (ASES) has a definite financial interest in the rapid expansion of solar power. Yet, in its recent publication claiming that renewables can offset fossil fuels, ASES admits that advanced PV technologies, such as thin-film PV, use rare materials including indium, selenium, and tellurium and that exhaustion of supplies could interfere with their development.One of most promising of new PV approaches is Titania Dye Sensitised Cells. Though most of the production involves common materials, the solar cell needs to be covered with transparent plastic. And what is plastic made from? Petroleum, the most infamous of non-renewable substances.

Though the amount of petroleum used to cover the planet with solar cells would be tiny compared to covering the world with cars, it drives home how important it is to make the focus of a sane energy policy preserving oil for genuine needs of future generations.An even more serious concern with the “renewability” of renewables is their use of land when they become the dominant sources of energy. Do we really want to fill every mountain pass, coastal area and valley with wind mills? ASES assures that “…land set aside specifically for solar PV generation will not need to occur until this technology provides a very large fraction (perhaps more than 25%) of the nation’s electricity.” (p. 95) Looking at it the other way, once solar PV replaces fossil fuel, it will encroach on wildlife habitat.The biggest reason that renewable energy may not be truly renewable is that it depends on fossil fuel to replace fossil fuel.

Total energy use in the US is currently about 100 quads. A quad is equivalent to a quadrillion (a one followed by 15 zeroes) Btu. In his classic The Party’s Over, Richard Heinberg observes that “to produce 18 quads of wind power in the US by 2030 would require the installation of something like half a million state-of-the-art turbines…That is five times the present world production capacity for turbines...most of the energy needed for that undertaking would have to come from dwindling fossil fuels.”


People would be consuming voraciously at the same time they were constructing a massive new energy infrastructure. Where would the energy for this gargantuan orgy of consumption/construction come from? Would it mean pumping every drop of oil out of the ground to move the new equipment across the globe? Would it require blowing the top off of every sacred mountain that had coal in it? Would it demand mining enough uranium to melt down nukes in every country? Would it mean extracting every cubic foot of natural gas so there was none left for heating by the time 2050 arrives? Switching to solar/wind by 2050 might require the greatest use of fossil and nuclear fuel the world has ever seen. That’s not a good way to prevent global warming.

The real issueCalculating the needed increase in solar and wind production only included a few quantifiable factors. It did not include how manufacture would exacerbate the exhaustion of water which is already shrinking due to industrial agriculture. It did not include the overrunning of the last acres of animal habitat and the resulting extinction of species.

Nor did it include the enormous increase in production of toxins which could do even more damage to humanity than changing weather conditions. The problem is that market economics pushes corporations to encourage the most rapid squandering of energy possible. There could be a doubling of available energy, a tripling of energy or an increase in solar and wind power of nine million percent and there would still be a shortage.

This is not to deny that solar panels are absolutely essential for a sustainable energy policy. It is to say that fanaticism about solar power which blinds people to its limitations can also blind them from seeing the need to reduce the total quantity of energy produced in Western countries.

Global warming is not a technological problem and no increase in the production of solar and wind and eco-gadgets can solve it. The energy crisis and rising CO2 levels are crises of market economics and the question we must ask is: How do we change society to make it sustainable?There is no shortage of energyConsider the following two assertions:1. There is already more energy than we need. 2. No matter how much energy is produced, it will not be enough. These two statements appear totally contradictory. Yet they are both true.

It is similar to food and starvation. There is enough food to feed everyone on the planet. Yet hunger is increasing. Agribusiness says that we need to fight starvation by increasing food production via another “Green Revolution” with pesticides, herbicides, genetic engineering and leveling of rain forests to plant crops to be sold to distant lands. None of those are necessary and will, in all likelihood, increase hunger.

People starve not because there is not enough food, but because available food is not distributed to those who need it. It is more profitable to process food and send it to those who overconsume in rich countries than it is to sell it to those in poor countries who can pay less for it. Local food production for need, combined with aid during times of crisis, could feed everyone. But increased corporate control of food means more production for the international market and food drained away from those who need it the most.

Corn for people to eat locally is transformed to corn to feed cattle for international hamburger chains. Less corn is available to solve hunger as American obesity skyrockets. A thousand food commodities and diabetes follow the same path.Just as an increase in the quantity of food can be followed by an increase in starvation, an increase in the quantity of energy available can accompany an energy shortage. If people controlled their energy locally, they could decide how much to produce and, more important, what types of energy-draining activities need to be limited. But increases in energy production occur simultaneously with control by big energy corporations. The more energy that it produces, the more big energy is motivated to sell it for wasteful practices.

Will big energy propose to end nighttime sports events with huge lights? To require that only fluorescent light bulbs be produced? To advocate for urban centers free of private automobiles? Not a chance. In a market economy, the goal of big energy is to make as much profit today from selling as much energy as possible and energy for real needs be damned. Big energy gleefully provides electricity for trivial pursuits in the overdeveloped world as poor villagers fell their remaining trees for firewood.

Even if perpetual motion machines or Star Trek replicators could increase the production of solar and wind by nine million percent, there would still be a shortage of energy. In a type of perverted Malthusianism, the market creates artificial desires faster than the planet’s ecosystems can sustain them.

The flip side is that just as plenty of food exists right now, there is already an abundance of energy. Humanity can live better, healthier and longer lives by changing habits of producing food, altering methods of transportation, building off-grid homes, limiting the manufacture of unnecessary junk, and halting the killing people to steal their oil. If we do these, there could be a smooth transition away from coal, oil, nukes and gas to solar, wind and other renewables. Without these changes, no quantity of renewable energy is enough.

http://www.zmag.org/content/showarticle.cfm?SectionID=56&ItemID=12654

Energy Under Water

April 2007
By COLLEEN LONG, Associated Press

NEW YORK -- The murky rivers around New York City bring to mind many things - garbage, chemicals, perhaps mobsters' bodies - but clean energy is not one of them.

The state is trying to change that thinking, however.

It is teaming with a Virginia company to use the East River for a unique experiment in renewable energy: Six giant turbines are being placed underwater in a $7 million project to harness the energy of the tides and produce electricity.

One of the 16-foot-diameter, windmill-like turbines is already operating, supplying power to a grocery store and a garage on Roosevelt Island. The other turbines are being installed during the next two weeks.

"We're looking for the most cost-effective way to get the most energy out of moving water while having a positive impact on the environment," Verdant Power President Trey Taylor said.

Hydroelectric and wind power operate on similar principles, with water or air turning turbines. But those projects require dams or windmills, which can be costly, intrusive and objectionable to environmentalists.Project organizers say this is the first time the underwater-turbine concept has been used in the U.S.

"We picked New York on purpose because the regulations are so strict and because the East River is a tidal strait. There is a high current," Taylor said. "You know what they say about New York: If you can make it here ..."The project is entering an 18-month testing phase. Its backers hope to expand use of the technology in New York if it works out.

One downside is that the river sometimes moves too slowly. On average, the turbines rotate enough to generate electricity only about 77 percent of the time. At full capacity, the 10-megawatt project could power 10,000 homes.

That is not much in a city of 8 million people, but it's a step in the right direction, environmentalists say."The biggest source of power is burning oil, coal and all of that," Taylor said. "That contributes to greenhouse gases, and in a city where this many people live, the idea of having a clean energy source is a real appeal.

"Some environmentalists worry that the project may harm fish by stirring up sediment or otherwise altering their habits. The river is not quite the cesspool it was 30 years ago, and it is home to striped bass, herring, smelt and sturgeon, many of which travel between the ocean and the river.

Taylor said the fish near the turbines are being monitored with sonar equipment, and the river bottom is mostly bedrock, so no sediment is being churned up. Commercial vessels do not use that section of the river, so shipping is unaffected.

Environmental groups would like to see a year's worth of data before deciding whether the 8,500-pound, steel-alloy turbines have any significant effects, but so far they are pleased.

"The idea that it is renewable energy is a really good thing," said Robert Goldstein of the environmental group Riverkeeper. "They seem to be acting very careful and moving forward in a responsible way."The New York State Energy Research and Development Authority has provided nearly $2 million toward design and environmental testing.

"We've had some blade failures, but we've already gotten back some great test results," said Ray Hull, a spokesman for the authority. "This could be a significant advance in renewable energy.

"Hull said the economics are hard to ignore, too: "During high tide periods in July and August, when there is such a demand for power, this could be pretty good stuff, financially speaking."Taylor is thinking bigger. He wants to place the technology in U.S. rivers such as the St. Lawrence or the Mississippi, and around the world.

"There are so many people that don't have access to electricity around the world," he said. "But many live near running water."
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