Tilting We Will Go?
Windmills are not an energy policy
T. Boone Pickens wants to solve the energy crisis by building windmill farms. With characteristic reticence, he is announcing his intentions with a series of slick, glossy TV and newspaper ads, a website (PickensPlan.org), and a forthcoming book. As often happens with autodidacts proclaiming a world vision, Pickens is about half right and half wrong.
As one of the most experienced and successful oilmen in the world, he is certainly on target about the threat diminishing oil supplies present to America: “We now import almost 70 percent of our oil. . . . Importing that oil is costing us $700 billion a year, $7 trillion over the next ten years. . . . World oil production has peaked at 85 million barrels a day while demand is still growing. Output may never go up again.” This is an important point, but Pickens’s solution is dangerously simplistic and naďve: “We now produce 22 percent of our electricity with natural gas. [Actually, it’s 20 percent.] I want to replace that 22 percent with wind energy and move the natural gas over to the transport sector, where compressed natural gas can replace oil. That will lower our oil imports by 38 percent. The federal government says it’s possible. It’s right here in this study, ‘20% Wind Energy by 2030,’ put out by the Department of Energy.”
DOE’s Office of Energy Efficiency and Renewable Energy did indeed put out such a report earlier this year. But the department, like any other federal bureaucracy, is a collection of fiefdoms pursuing their own particular passions. DOE has also put out studies supporting clean coal, geothermal energy, biofuels, and just about anything else you can name. Take your pick.
So why isn’t Pickens backing nuclear power, which seems like a much more promising way to generate large amounts of new electricity? Pickens told The American Spectator that he worries about costs and uranium supplies. Still, he is spending $10 billion on his 4,000-megawatt (MW) wind farm, about the same as what it would cost to build 4,000 MW of nuclear capacity. So what’s going on?
What Pickens is really saying is that nuclear investment right now is too risky. Although proposals for nine new reactors are currently before the Nuclear Regulatory Commission, no one knows exactly what will happen when these applications enter the approval process. As Greenpeace beats the tambourines about “more Chernobyls,” as mainstream environmental groups hem and haw about how they support nuclear in principle but not in this particular instance, as the public remains confused about whether a reactor really can blow up or become the target of a terrorist attack, completion of a single reactor could easily stretch out 15 years or more, as it did in the 1970s and 1980s, leaving a trail of ruined investors in its wake.
A windmill, however, can be put up in three months and, most important for investors, start collecting its production credit on federal taxes immediately. In half the states, utilities are mandated to fill “renewable portfolios” with things like wind energy, whether it is useful or not. Pickens told Fast Company he expects to make a 15 percent — perhaps 25 percent — profit on his West Texas wind farm. You can’t guarantee that to a nuclear investor. Windmills will reap plenty of profits from all the subsidies and mandates — yet their contribution to the nation’s energy budget is likely to be marginal at best.
In the absence of any real market signals that haven’t been drowned out by politics, the best way to compare different energy strategies is a simple concept called “energy density.” As the term implies, energy density is a measure of how much energy can be produced from a specified unit of weight, volume, or area. In essence, it shows how concentrated a pool of energy is as we find it in nature.
Nearly all the energy on earth originated as radiation from the sun. Somewhere around 750,000 years ago, early humans discovered the vast quantities of solar energy stored in dried plant material, and fire became a source of supplementary heat and light. Then, as forests began to disappear in the 17th century, Europeans discovered another source of stored sunlight in fossil fuels. These represent the accumulation of solar energy over millions of years. Coal is the most abundant — we will probably never run out of it — and the octane molecules in gasoline are probably the densest storehouse of solar energy we will ever encounter. Pound for pound, coal contains twice as much energy as wood, and gasoline and natural gas contain four times as much. The Industrial Revolution became possible only when these denser forms of solar energy were developed.
Now, as we begin to run up against the natural limits of fossil fuels, it is important to consider the energy density of anything we might use in their place. Wind, water, biofuels, and the direct use of sunlight are anywhere from 5 to 50 times more dilute than fossil fuels. There is only one way to compensate for their low density, and that is to consume huge amounts of land in gathering them.
This is the Achilles heel of every form of “alternative energy.” When first introduced in the 1970s, alternative energy came with the slogan “Small is beautiful.” Prophets such as Amory Lovins, David Brower, and Lester Brown pictured a post-industrial world of backyard windmills, rooftop solar collects, and organic gardens where small plots would be set aside for biofuels that would run hyper-efficient cars. Self-sufficiency was the theme. It all sounded charming and romantic.
The reality has been anything but. We now use one-quarter of America’s corn crop for biofuels in order to replace less than 4 percent of our oil. GreenFuel Technologies, a Massachusetts startup, has a plan to grow photosynthesizing algae that will consume the carbon emissions from coal plants, and can be turned into biodiesel to run cars. It sounds like a great idea, except that the pools required for gathering sunlight to convert 40 percent of the exhausts from a single power plant will occupy 15 square miles.
T. Boone Pickens will soon be running up against a similar density problem with his wind farms. A standard wind farm built to generate 1,000 MW — the capacity of an average coal or nuclear plant — would occupy about 125 square miles. Pickens wants to space his windmills a little wider — five to the square mile instead of eight — so for his 4,000 MW he will need 800 square miles.
But that 4,000 MW is only the “nameplate capacity.” Because wind blows so irregularly, even the best wind farms now generate electricity at only 30 percent of their theoretical capacity. (By contrast, nuclear reactors run at 92 percent capacity.) That means he will need 1,200 square miles of windmills to equal the output of three or four coal or nuclear plants, each of which occupies only a square mile. Factoring in the land required for mining adds several square miles for coal, and much less for uranium.
Even then, the electricity generated by windmills is not what the industry calls “dispatchable,” meaning able to be produced and delivered when and where needed. As the authors of “20% Wind Energy by 2030” write:
Incorporating wind energy into power system planning and operation, then, will require new ways of thinking about energy resources. . . . Thinking in terms of “backing up” the wind is not appropriate because the wind capacity was installed to generate low-emissions energy but not to meet load growth requirements. Wind power cannot replace the need for many “capacity resources,” which are generators and dispatchable load that are available to be used when needed to meet peak load.
In other words, don’t count on its being there — backup from other resources will always be necessary. Building and maintaining a wind-power infrastructure is a supplement, not a replacement, for fossil-fuel plants.
Part of the mistaken belief that wind can be a reliable source of electricity comes from a misapprehension of what the “grid” is. The national grid is not a machine for churning out electricity. It is more like a high-wire act — the Flying Wallendas balancing six people on a bicycle 50 feet above the ground.
Electricity must be consumed the moment it is generated; there are no methods for storage on an industrial scale. This means that supply and demand must constantly match within about 5 percent. Otherwise there will be power “dips” or “surges,” which can cause brownouts, ruin electrical equipment, or even bring the whole system crashing down.
Traditionally, maintaining voltage balance has involved two things: (1) matching supply with demand through the normal daytime/nighttime fluctuations, with demand usually peaking around mid-afternoon, and (2) maintaining a “spinning reserve” against sudden losses of power, in case an overloaded transmission line brushes against a tree and shorts out, or a generator unexpectedly shuts down. Utilities generally build “peaking plants” to handle high daytime demand, then carry a “spinning reserve” of 20 percent of output to guard against shutdowns.
GONE WITH THE WIND
Now imagine introducing a power source that is constantly fluctuating. The output of a windmill varies with the cube of wind speed, so it can change greatly from minute to minute. Putting windmills on the grid is a little like the Flying Wallendas’ hiring a new crew member to shake the wire while they are doing their balancing act. Engineers who work on electrical grids have been quietly complaining for years, and over the last decade, grid operators in Denmark, Japan, and Ireland have all refused to accept more wind energy. In fact, Denmark — the world leader in wind generation — stopped building windmills altogether in 2007. After long discussions at numerous symposiums and in professional energy journals, a consensus has emerged that, even with very accurate weather forecasts and other improvements, a grid can at best tolerate a maximum of 20 percent wind energy. Above that, the fluctuations become too difficult to mask. That’s why DOE chose the 20 percent–by–2030 goal.
Even reaching that magical 20 percent, however, won’t mean replacing the 20 percent of electricity that is produced with natural gas. That’s because not all generating capacity is interchangeable. Different power sources play different roles on the grid, so while some gas generators may see less use if wind power is added, the role of others will actually increase.
Natural-gas electric plants come in two types. The first type consists of “combined cycle” plants, almost all of which are large-scale installations. They produce electricity by burning natural gas and using the resulting ultra-hot exhausts to drive a generator, then extracting leftover heat to make steam, which drives another turbine. These highly efficient plants convert 60 percent of the fuel’s energy into electricity, as opposed to 30 percent in ordinary steam boilers.
The second kind of natural-gas electrical generators are “gas turbines,” which are essentially jet engines bolted to the ground. Since they do not boil water for steam, they can be started in an instant, making them excellent for following peak loads. But they do not have the efficiency of combined-cycle and are very expensive to operate.
Combined-cycle natural-gas plants have been the most commonly built type of power plant since 1990, mainly because they produce less air pollution than coal. But now that natural gas has become expensive, many of these plants are sitting idle. Although gas constitutes 39 percent of our generating capacity, it generates only 20 percent of our electricity. (Nuclear, on the other hand, constitutes 10 percent of capacity but produces 19 percent of our electricity because reactors are running all the time.) So natural-gas generation is, indeed, sensitive to competition, and as far as these large-scale installations are concerned, Pickens is right: Bringing windmills online will probably mean cutting down production from some coal and combined-cycle natural-gas plants.
Gas turbines, on the other hand, will become more important as wind is incorporated onto the grid. They will have to be on constant standby to raise and lower voltage with the wind’s fluctuation. So wind power will reduce some uses of natural gas in electrical generation, but require more of it in others. As a generally pro-wind study by the National Renewable Energy Laboratory concluded: “The 20% Wind Scenario would . . . supply enough energy to displace about 50% of electric utility natural gas consumption and 18% of coal consumption by 2030.” There goes half of Pickens’s projected saving, which depended on displacing 100 percent of electric-utility natural-gas consumption.
If Pickens’s dream is realized, you will probably be able to drive from Texas to North Dakota without ever being out of sight of a windmill — just as they are visible everywhere in western Denmark. The one oasis may be Pickens’s own 68,000-acre property in the Texas panhandle. “I’m not going to have the windmills on my ranch,” he told Fast Company. “They’re ugly.”
Oh, there’s one more rub. Bringing windmills online will require building a whole new cross-country transmission system. While wind energy is concentrated in the Midwest, consumer demand is mostly on the East and West Coasts. Normal transmission lines — of 138 kilovolts (kV) and 345 kV — lose about 10 to 15 percent of their wattage every 1,000 miles, which is not a problem when the power is generated close to the consumer. But transmitting electricity halfway across the country will require a completely new infrastructure of 765 kV lines that cover long distances without losing power. This could be an enormous problem, because utility executives now say the only thing more difficult than siting a power plant is building new transmission lines, since every property owner and municipal jurisdiction in the path gets to have a say. Ranchers who are as just as picky as Pickens about what they permit on their land could pose huge obstacles.
IF NOT WIND, WHAT?
Is there a way out of this conundrum? There certainly is. The greatest scientific discovery of the 20th century was the vast store of energy concentrated in the nucleus of the atom. The energy released from splitting a uranium atom is 2 million times greater than the energy released by breaking a carbon-hydrogen bond in coal.
The tremendous energy density in uranium produces an extraordinarily smaller environmental footprint. It explains why uranium can be mined at a few isolated sites, while coal must be extracted by digging whole cities underground or ripping the tops off mountains, as is being done in West Virginia. It explains why a 1,000 MW coal plant must be fed by a 110-car coal train arriving every day, while a nuclear reactor is refueled by a single tractor-trailer delivering a batch of new fuel rods once every 18 months. It explains why France can take all the waste from 25 years of producing 75 percent of its electricity with nuclear reactors and store it beneath the floor of one room at La Hague. The incredible energy density in the nucleus of the atom is the greatest environmental benefaction ever bestowed upon humanity.
Even so, we will probably continue littering the American landscape with marginally productive windmills. With a 1.5-cent-per-kilowatt-hour tax credit permanently in place, and with utilities mandated to buy “renewable” electricity, investors can hardly lose. Meanwhile, anyone who elects to put money into nuclear reactors faces much greater risks — even though, in the long run, their contribution to our energy budget will be vastly more valuable.
With the overwhelming advantages that nuclear power offers, it is hard to imagine it will not be part of the solution to the world’s energy problems — as its success in France already illustrates. Yet economic advantage means little when politicians and interest groups have usurped the power of choice. And so the battle will be in large part political. It’s time for the public to awaken to the enormous, unparalleled benefits of nuclear energy.