Articles in this series will periodically examine the ways in which the world is, and is not, moving toward a more energy efficient, environmentally benign future.
The installment on wind power from back in December: “It’s Free, Plentiful and Fickle”.
Wind power — promoted by many — is it marginal or a central part of a move toward a better energy future?
Wind, almost everybody’s best hope for big supplies of clean, affordable electricity, is turning out to have complications.
And, as you will see below, those “complications” are absolutely nothing new in terms of conceiving of wind power.
Engineers have cut the price of electricity derived from wind by about 80 percent in the last 20 years, setting up this renewable technology for a major share of the electricity market.
Yes, wind is now the cheapest new major electrical power with the exception of coal, as long as one doesn’t count ‘minor’ externalities like Global Warming implications.
But for all its promise, wind also generates a big problem: because it is unpredictable and often fails to blow when electricity is most needed, wind is not reliable enough to assure supplies for an electric grid that must be prepared to deliver power to everybody who wants it — even when it is in greatest demand.
This is it … the stumbling block … periodicity. Actually, this is both absolutely true and, perhaps, exaggerated.
In Texas, as in many other parts of the country, power companies are scrambling to build generating stations to meet growing peak demands, generally driven by air-conditioning for new homes and businesses. But power plants that run on coal or gas must “be built along with every megawatt of wind capacity,” said William Bojorquez, director of system planning at the Electric Reliability Council of Texas.
The reason is that in Texas, and most of the United States, the hottest days are the least windy. As a result, wind turns out to be a good way to save fuel, but not a good way to avoid building plants that burn coal.
Actually, from what I understand, coal plants would be abad choice for balancing wind — it is gas turbine plants that can be quickly turned on/off to deal with interruptions in the fuel system.
A wind machine is a bit like a bicycle that a commuter keeps in the garage for sunny days. It saves gasoline, but the commuter has to own a car anyway.
This is a cute line. Really is. But, isn’t it demeaning to wind power as, after all, how many commuter readers of the NYTimes ever get out of their cars to ride a bike to work?And, this isn’t just saving gasoline, but also saving money and reducing pollution — something beyond this article, it seems.
Xcel Energy, which serves eight states from North Dakota to Texas and says it is the nation’s largest retailer of wind energy, is eager to have more. Wind is “abundant and popular,” said Richard C. Kelly, the chairman, president and chief executive, speaking at a recent conference on renewable energy.
But Frank P. Prager, managing director of environmental policy at the company, said that the higher the reliance on wind, the more an electricity transmission grid would need to keep conventional generators on standby — generally low-efficiency plants that run on natural gas and can be started and stopped quickly.
He said that in one of the states the company serves, Colorado, planners calculate that if wind machines reach 20 percent of total generating capacity, the cost of standby generators will reach $8 a megawatt-hour of wind. That is on top of a generating cost of $50 or $60 a megawatt-hour, after including a federal tax credit of $18 a megawatt-hour.
To be honest, information from XCel is something that I take seriously. Without other information, I will accept at face value the $8 mwh figure.But the $50-60 cost per megawatt-hour might be high … again, I don’t have internal industry data, but I might have placed the bottom number a good 10-20 percent lower.
As for that tax credit … it is great, truly, a ‘subsidy’ for clean power. Might there be a value to mentioning that other energy systems have subsidies, from tax benefits, to minimized royalty payments, to …
By contrast, electricity from a new coal plant currently costs in the range of $33 to $41 a megawatt-hour, according to experts. That price, however, would rise if the carbon dioxide produced in burning coal were taxed, a distinct possibility over the life of a new coal plant. (A megawatt-hour is the amount of power that a large hospital or a Super Wal-Mart would use in an hour.)
This also assumes that coal does not go up in price … which could be a dangerous assumption.
This is also a good point to mention that the NYTimes speaks in terms that have little meaning to most Americans. Your electricity bill comes in kilowatts, not megawatts. Yup, that’s right, divide by 1000. In other words, without a carbon tax, coal plants generate power at 3.3 to 4.1 cents per kwh (although most utility bills don’t reflect that number — average delivered electricity in the US is about 9 cents/kwh, there is delivery costs and profits that are not included in the cited price here).
Without major advances in ways to store large quantities of electricity or big changes in the way regional power grids are organized, wind may run up against its practical limits sooner than expected.
At a recent discussion of clean energy technologies held at General Electric’s research center in Niskayuna, N.Y, Dan W. Reicher, a former assistant secretary of energy for conservation and renewable energy, predicted that renewables, led by wind, could reach 20 percent of demand in the next decade or two. President Bush has also said that wind could supply 20 percent of the nation’s electricity.
But Mr. Reicher drew a quick response from James E. Rogers, chief executive of Cinergy, one of the nation’s largest utilities, and chairman of the Edison Electric Institute, the industry’s trade association. “I love his optimism,” Mr. Rogers said. “But unfortunately, I have to deliver electricity every day.”
Mr. Rogers said that wind and another big renewable source that is available only when nature cooperates, solar power, will be necessary because the government would eventually regulate carbon emissions from coal-fired power plants. He later said that his reply to Mr. Reicher had been a “cheap shot,” but he and others are still wondering how much wind the nation can absorb.
This really is the meat of the challenge. How much wind power can the system absorb without major change. The rough rule of thumb has been 20% of the total capacity. A recent study suggests in Minnesota suggests 25 percent. Well, Rogers’ challenge should not be taken lightly. On the other hand, has the EEI or Cinergy been at the forefront of renewable energy advances? Warmly embraced change toward a less polluting electricity future?
General Electric, a major maker of wind machines, says that along with lowering the price for a megawatt-hour, engineers have made other improvements in wind machines. With better electronic controls, many of them now help stabilize voltage on the grid, and have been cured of their tendency to shut off when detecting a voltage fluctuation, a problem that can escalate into a blackout.
Juan de Bedout, manager of the electric power and propulsion systems lab at G.E., said this was more important now because wind machines had grown from a few hundred kilowatts to 1.5 gigawatts, and his company was exploring machines four times bigger than that. “That’s ginormous,” he said.
‘Ginormous’ — that’s so cute. Have to say that I really don’t understand the placement of these paragraphs, this is filler that simply doesn’t flow. … But, it does increase one’s nervousness about ‘ginormous’ wind mills that can ‘escalate into a blackout’ … Believe I place this complaint at the editor’s desk …
In many places, wind tends to blow best on winter nights, when demand is low. When it is available, power from wind always displaces the most expensive power plant in use at that moment. If wind blew in summer, it would displace expensive natural gas. But in periods of low demand, it is displacing cheap coal.
And in places where suppliers enter bids each day to supply power on the next day, on an hour-by-hour basis, wind is at a disadvantage. Wider use of wind requires the invention of a new kind of weather forecasting, according to the Electric Power Research Institute, a nonprofit consortium based in Palo Alto, Calif., sponsored by the utility industry and its suppliers. Rather than forecasting from temperature or rainfall, what is needed is a focus on almost minute-by-minute predictions of wind in small areas where the turbines are.
This is raising several interesting issues. Again, this is basically saying that wind doesn’t blow when you need electricity. That doesn’t seem to be Europe’s experience but … okay. The comment about new weather forecasting is quite interesting … and, to display my ignorance, is a challenge that I hadn’t heard before. Thank you NYT.
The economics of wind would change radically if the carbon dioxide emitted by coal were assigned a cash value, but in the United States it has none. Coal plants produce about a ton of carbon dioxide each megawatt hour, on average, so a price of $10 a ton would have a major impact on utility economics.
This $10 per ton would equate to roughly one cent per kilowatt hour, still leaving coal cheaper than wind. A Global Warming Impact Fee of $10 the first year, and going up by that amount (with coordination with other countries) every year. That would quickly favor options less damaging to the environment.
Another possibility is energy storage, although this presents other difficulties.
In May, Xcel and the Energy Department announced a research program to use surplus, off-peak electricity from wind to split water molecules into hydrogen and oxygen. The hydrogen could be burned or run through a fuel cell to make electricity when it was needed most. Xcel plans to invest $1.25 million, and the government $750,000. But storage imposes a high cost: about half the energy put into the system is lost.
The Electric Power Research Institute said that existing hydroelectric dams could be used as storage; they can increase and decrease their generation quickly, and each watt generated in a wind machine means water need not be run through the dam’s turbines; it can be kept in storage, ready for use later, when it is most needed.
Storage is a challenge —
The institute listed another possibility, still in the exploratory stage: using surplus electricity made from wind to pump air, under pressure, into underground caverns. At peak hours, the compressed air could be withdrawn and injected into generators fired by natural gas. Natural-gas turbines usually compress their own air; compression from wind would cut gas consumption by 40 percent, the institute said.
Note that there are already projects to useair pressure storage underground for dealing with the periodicity challenge.
That would help with an important goal, reducing consumption of natural gas, which is increasingly scarce and costly in North America. But not everyone is so sanguine that wind will do that.
Paul Wilkinson, vice president for policy analysis at the American Gas Association, the trade group for the utilities that deliver natural gas, said that wind, while helpful in making more gas available for home heating and industrial use, would still need a gas generator to back it up. And the units used as backup are generally chosen for low purchase price, not efficient use of fuel.
Note the use of industry spokesman for supporting arguments — the AGA isn’t enthusiastic about wind, which is its largest competitor for new installation at this time. And, which successfully implemented, could drastically cut future demand for natural gas for electrical generation. And, AGA isn’t enthusiastic?
But, if the backup system is required to produce far less electricity, one can calculate the cost/benefit issues of efficiency — these backup units, even if less efficient, would likely burn less fuel total partnered with wind than a more efficient system that was not associated with wind energy.
At the American Wind Energy Association, Robert E. Gramlich, the policy director, said that one solution would be to organize control of the electric grid into bigger geographic areas, so that a drop-off in wind in one place would be balanced by an increase somewhere else, reducing the need for conventional backup. That is among several changes the wind industry would like in the electric system; another is easier construction of new power lines, because many of the best wind sites are in prairies or mountain ranges far from where the electricity is needed.
A problem for new power lines is that they would be fully loaded for only some of the year, since the amount of energy that the average wind turbine produces over 12 months is equal to just 30 to 40 percent of the amount that would result from year-round operation at capacity. That number runs closer to 90 percent at a nuclear or coal plant.
Actually, I believe that Gramlich’s point is somewhat different. That with a smarter, more efficient national grid, energy could be moving between different regions — balancing wind blowing in one location with another. And, re the capacity numbers, without a fuller explanation, one might ask, SO WHAT? This is factored into the pricing structure per kwh for wind — their load factor will be lower than that for nuclear or coal or an ocean-wave system.
Thus a 1,000-megawatt nuclear plant will produce nearly three times as much electricity as 1,000 megawatts of wind turbines. But operating costs at the wind farm are lower, and the fuel is, of course, free.
So, again, we must ask why in the world this matters in this article which does not have a complete explanation of how energy output is measured and how energy production systems are balanced.So what is missing in this article? Here are just a few things …
1. Any indication as to the fast pace of growth in the wind industry, which is solidly double-digit worldwide for years now. Some statistics from the American Wind Energy Association
In the United States, the first megawatt of wind power was achieved in 1985, the second in 1999, the 10 megawatt level came in August 2006 … exponential growth! Wind was the second-largest source of new power generation in the country in 2005 after natural gas, and is likely be so again in 2006, according to the Energy Information Administration.
Predicted figure for 2007: 26%, 2006 was a 27% growth rate.
- Wind’s current penetration of the US electrical system — just passed 1 percent, if I recall correctly …
- Statistics about environmental benefit. Again, from AWEA, “today’s 10,000 MW of wind power are keeping 16 million tons of carbon dioxide (CO 2), the leading greenhouse gas associated with global warming, out of the air EVERY YEAR.”
- Semi-esoteric storage concepts, such as fly wheels or, much more massively, associating wind power and its periodicity with using Plug-in Hybrids (PHEVs)/Electric Vehicles (EVs) connected to a smarter grid as storage devices. This could be the major break through, with a smart grid, that could utterly change the role of renewable power systems and enable a much more stable electrical system. (Note, for a good paper about storage options, see Energy storage options for improving wind power quality (warning, PDF) from May 2006.)
- Small-scale wind, such as roof-top wind. (For example, no endorsement, although I am intrigued, the newly put on the market Mag-Wind 1100. There are MANY other options out there — for a good discussion, see : Rooftop Wind: Where we are at. )
- Not discussion of NIMBY, which is surprising considering the battle over Cape Wind.
- Any serious discussion of critical financial issues. For example, the #1 issue is that wind power is principally a major upfront construction cost with relatively low operating costs compared to the reverse for coal/gas plants. And, that wind power provides a more distributed revenue stream, with more jobs per kwh and money being paid as rent to, for example, farmers who can still farm their land beneath wind turbines.
- Any sort of balanced discussion, pointing toward energy efficiency and changed usage patterns as part of the solution path. This is far from holistic thinking about energy issues and challenges. But, to give credit, I have not read the entire series and efficiency/conservation options might be covered elsewhere.
I plan to go back and read all the series. And, go through the comments. With the issues that I have with this article, I wonder what serious reading of the others might reveal. And, if this is what a key newspaper of record, with ‘top-notch’ journalists, is providing to its readership, we should all be concerned about what is appearing elsewhere.