The Siren Song of Renewable Energy

Renewable energy from the sun—which includes solar, wind, and water energy— can meet all of our energy needs and will allow us to eliminate our dependence on fossil fuels for electricity production. At least, that is the “Siren song” that seduces many people. Amory Lovins, the head of the Rocky Mountain Institute, has been one of the strongest proponents of getting all of our energy from renewable sources (what he calls “soft energy paths”) (1) and one of the most vociferous opponents of nuclear power. A recent article in Scientific American proposes that the entire world’s needs for power can be supplied by wind, solar, and water (2). Is this truly the nirvana of unlimited and pollution-free energy? Can we have our cake and eat it, too? Let’s take a critical look at the issues surrounding solar and wind power. Let me be clear that I am a proponent of solar energy. I built a mountain cabin a few years ago that is entirely off the grid. All of the electricity comes from solar photovoltaic (PV) panels with battery storage. The 24 volt DC is converted to AC with an inverter and is fed into a conventional electrical panel. It provides enough energy to power the lights, run a 240 volt, three-quarter horsepower water pump 320 feet deep in the well, and electrical appliances such as a coffee pot, toaster, and vacuum cleaner. But I am not implying that all of my energy needs come from solar. The big energy hogs—kitchen range, hot water heater, and a stove in the bedroom—are all powered with propane. Solar is not adequate to power these appliances. In 2010 I also had a 2.5 kW solar PV system installed on my house that ties into the utility grid. When the sun is shining, I use the electricity from the solar panels, and if I use less than I generate, it goes out on the grid to other users. If it does not produce enough for my needs, then I buy electricity from the grid.

The Good, Bad, and Ugly of Coal and Gas

About ten miles north of where I live in northern Colorado, a smokestack rises 500 feet in the air alongside a stair-step series of buildings. On a summer day, nothing appears to be coming from the smokestack, as though it is a ghostly relic; in the winter, a white plume rises. On closer approach, a lake teeming with ducks, geese, pelicans, and other waterfowl sits in the foreground. A herd of American bison roam on over 4,000 acres of grasslands surrounding the smokestack. This apparently benign plant called Rawhide Energy Station is actually a 280 MWe coal-fired power plant that provides about one-quarter of the electricity for four nearby communities—Fort Collins, Loveland, Longmont, and Estes Park. It is a public utility owned by the four communities and is near state-of-the-art for a coal-fired power plant, being one of the most efficient in the western United States and among the top ten in lowest emissions. I drove up to the Rawhide Energy Station and called on an intercom box to the security station to identify myself so the guard could open the security gate for me to enter. After driving across the edge of the lake, the armed guard then directed me to the visitor center. I met Jon Little, the knowledgeable and friendly tour guide, and a group of bicyclists from a local environmentally conscious brewery who were taking the tour also. We put on headphones with a radio set and a hard hat for the tour. The first and largest building houses the boiler and the generators. Th e coal arrives by train in five- to six-inch lumps, which are broken down into one-inch lumps before being fed by conveyor to grinders that convert it into a powder finer than facial powder. This powder is then mixed with air and blown into the 16-story. boiler from four directions, where it burns efficiently at a hellish temperature of 2,800˚F.

Global Climate Change: Real or Myth?

We, the teeming billions of people on earth, are changing the earth’s climate at an unprecedented rate because we are spewing out greenhouse gases and are heading to a disaster, say most climate scientists. Not so, say the skeptics. We are just experiencing normal variations in earth’s climate and we should all take a big breath, settle down, and worry about something else. Which is it? A national debate has raged for the last several decades about whether anthropogenic (man-made) sources of carbon dioxide (CO2 ) and other so-called “greenhouse gases“ (primarily methane and nitrous oxide) are causing the world to heat up. This phenomenon is usually called “global warming,” but it is more appropriate to call it “global climate change,” since it is not simply an increase in global temperatures but rather more complex changes to the overall climate. Al Gore is a prominent spokesman for the theory that humans are causing an increase in greenhouse gases leading to global climate change. His movie and book, An Inconvenient Truth, gave the message widespread awareness and resulted in a Nobel Peace Prize for him in 2008. However, the message also led to widespread criticism. On the one hand are a few scientists and a large segment of the general American public who believe that there is no connection between increased CO2 in the atmosphere and global climate change, or if there is, it is too expensive to do anything about it, anyway. On the other hand is an overwhelming consensus of climate scientists who have produced enormous numbers of research papers demonstrating that increased CO2 is changing the earth’s climate. The scientific consensus is expressed most clearly in the Fourth Assessment Report in 2007 by the United Nations–sponsored Intergovernmental Panel on Climate Change (IPCC), the fourth in a series of reports since 1990. The IPCC began as a group of scientists meeting in Geneva in November 1988 to discuss global climate issues under the auspices of the World Meteorological Organization and the United Nations Environment Program.

Nuclear Waste

I gazed over the railing into the crystal clear cooling pool glowing with blue Cherenkov light caused by particulate radiation traveling faster than the speed of light in water. I can see a matrix of square objects through the water, filling more than half of the pool. It looks like you could take a quick dip into the water, like an indoor swimming pool, but that would not be a good idea! It is amazing to think that this pool, about the size of a ranch house, is holding all of the spent fuel from powering the Wolf Creek nuclear reactor in Burlington, Kansas, for 27 years. The reactor was just refueled about a month before my visit, so 80 of the used fuel rod assemblies were removed from the reactor and replaced with new ones. The used fuel rods were moved underwater into the cooling pool, joining the approximately 1,500 already there. There is sufficient space for the next 15 years of reactor operation. There is no danger from standing at the edge of this pool looking in, though the levels of radon tend to be somewhat elevated and may electrostatically attach to my hard hat, as indeed some did. What I am gazing at is what has stirred much of the controversy over nuclear power and is what must ultimately be dealt with if nuclear power is to grow in the future—the spent nuclear fuel waste associated with nuclear power. What is the hidden danger that I am staring at? Am I looking at the unleashed power of Hephaestus, the mythical Greek god of fi re and metallurgy? Or is this a more benign product of energy production that can be managed safely? What exactly is in this waste? And is it really waste, or is it a resource? To answer that question, we have to understand the fuel that reactors burn. The fuel rods that provide the heat from nuclear fission in a nuclear reactor contain fuel pellets of uranium, an element that has an atomic number of 92 (the number of protons and also the number of electrons).

The Quest for Uranium

The name rises as a phantom from the heart of the Congo. The dawn of the nuclear age began there, though no one knew it at the time. King Leopold II of Belgium claimed the Congo as his colony during the surge of European colonization in the 1870s, promising to run the country for the benefit of the native population. Instead, he turned it into a giant slave camp as he raped the country of its riches. Leopold didn’t care much about mineral wealth, preferring the easy riches of rubber, but aft er he died in 1909, the Belgium mining company Union Minière discovered ample resources of copper, bismuth, cobalt, tin, and zinc in southern Congo. The history-changing find, though, was high-grade uranium ore at Shinkolobwe in 1915. The real interest at the time was not in uranium—it had no particular use—but in radium, the element the Curies discovered and made famous. It was being used as a miracle treatment for cancer and was the most valuable substance on earth—30,000 times the price of gold. Radium is produced from the decay of uranium aft er several intermediates (see Figure 8.3 in Chapter 8), so it is inevitable that radium and uranium will be located together. The true value of the uranium would not be apparent until the advent of the Manhattan Project to build the atomic bomb during World War II. Edgar Sangier, the director of Union Miniere, which owned the mine at Shinkolobwe, hated the Nazis and was afraid—correctly, as it turned out—that they would invade Belgium. In 1939, as Europe was sliding into war, Sangier learned that uranium could possibly be used to build a bomb. He secretly arranged to transfer 1,250 tons of the uranium ore out of the Congo to a warehouse in New York City. There it sat until 1942, when General Leslie Groves, the man whom President Roosevelt put in charge of the Manhattan Project, found out about it and arranged to purchase it.

How Dangerous Is Radiation?

Many people think that radiation is extremely dangerous. Helen Caldicott, a long-time anti-nuclear activist, claims that “a single mutation in a single gene can be fatal,” meaning it could cause a fatal cancer. She is a physician and she ought to know better. Plutonium is frequently stated as the most dangerous element on earth. Helen Caldicott also says: “Plutonium is so carcinogenic that the half ton of plutonium released from the Chernobyl meltdown is theoretically enough to kill everyone on earth with lung cancer 1,100 times if it were to be distributed uniformly in the lung of every human being”. This is sort of like saying that a man theoretically has enough sperm to impregnate every woman on earth. The big problem is distribution! Nobody actually died from plutonium released in the Chernobyl accident, and a man cannot impregnate all the women in the world! These kinds of hypothetical scare-mongering statements get a lot of press, but they are far removed from the reality of the risks of radiation. But what are the actual risks? To understand the risks of radiation, we must begin at the atomic level to see what radiation does, and we have to consider the different kinds of radiation and, most important, the dose. This is going to be a somewhat technical chapter, but I hope you will stick with it. If you do, you will have a much better understanding of what radiation actually does to cells and how different types of radiation have different consequences. Let’s begin with the various kinds of radiation and how they interact with atoms. There are four kinds of radiation associated with nuclear power— α , β , γ and neutrons— as discussed in Chapter 6. X-rays and γ rays are basically the same type of radiation, and they interact with matter in exactly the same way, so I will consider them as one type: electromagnetic radiation. Their interactions with matter depend on their particle nature as photons with energy hf. The rules governing electromagnetic radiation are different from the rules governing charged particle radiation, such as α and β radiation.

About Those Accidents

A nuclear power plant is undergoing an emergency shutdown procedure known as a “scram” when there is an unusual vibration and the coolant level drops precipitously. Subsequent investigation by a shift supervisor reveals that X-rays of welds have been falsified and other problems exist with the plant that could potentially cause a core meltdown that would breach the containment building and cause an explosion. However, the results of the investigation are squelched and the plant is brought up to full power. The shift supervisor takes the control room hostage but is then shot by a SWAT team as the reactor is scrammed. A meltdown does not actually occur. No, this did not really happen, but these events—portrayed in the movie The China Syndrome —evoked a scenario in which a nuclear core meltdown could melt its way to China and contaminate an area the size of Pennsylvania. It also exposed a nuclear power culture that covered up safety issues rather than fixing them. It made for a compelling anti-nuclear story that scared a lot of people. And then a real core meltdown happened, 12 days later. The worst commercial nuclear power reactor accident in US history began on Three Mile Island, an island in the Susquehanna River three miles downstream from Middletown, Pennsylvania (hence its name). Two nuclear reactors were built on this island, but one of them (TMI-1) was shut down for refueling while the other one (TMI-2) was running at full power, rated at 786 MWe. At 4:00 a.m., what should have been a minor glitch in the secondary cooling loop began a series of events that led to a true core meltdown, but no China syndrome occurred and there was little contamination outside the plant. Nevertheless, it caused panic, roused anti-nuclear sentiment in the country, and shut down the construction of new nuclear power plants in the United States for decades. The nuclear reactors at Three Mile Island were pressurized water reactors (PWR), the type of reactor that Admiral Rickover had designed for power plants in US Navy nuclear submarines.

What Comes Naturally and Not So Naturally

“How many of you who moved to Colorado from Texas or Florida took into account that you were nearly tripling your annual dose of natural radiation by studying here?” That is the first question I ask students in my radiation biology class at Colorado State University, and of course none of the students considered that they were increasing their exposure to radiation by a large factor simply by moving here to live. And none of them would have used that as a reason to not study here. In contrast, if they were moving near a nuclear power plant in their state, they might have had second thoughts, even though they would be exposed to far less radiation than by coming to Fort Collins, Colorado. There is no place on earth where you are not exposed to radiation. As I said in the previous chapter, life evolved in a radiation environment. But where does the radiation come from, and why is it higher in Colorado than elsewhere in the United States? Are there other areas in the world where it is even higher? Do we get a lot more cancer in Colorado than in other lower radiation states because we are exposed to more radiation? These are important questions—they help us to understand the risk from a particular dose of radiation and put into perspective the exposure to radiation from the nuclear fuel cycle. We are exposed to radiation that comes from the skies, from the earth, and from our food. These are all natural sources, and there is not much we can do about it except decide where we want to live. But our decisions as to where we want to live almost certainly do not take into account the exposure to background levels of radiation from natural sources. The other main not-so-natural source of radiation exposure comes from medical procedures, a source that is increasing rapidly.

Back to the Future: Nuclear Power

Nuclear power is considered by many to be an old technology locked in the past— they say the future is with solar and wind. Commercial nuclear power began in 1951 when Russia built the first civilian nuclear power reactor, followed by the British in 1956 and the Americans in 1957. In the 1960s and 1970s, nuclear power plants blossomed all over the world. There were 42 reactors in the United States in 1973; by 1990 there were 112. Some of these were closed, so by 1998 there were 104 operating nuclear reactors (the same number operating at the end of 2012) providing about 100 GWe (gigawatts electric ) to the grid. Worldwide, there were 432 operating nuclear reactors as of mid-2013. Nuclear reactors have been providing about 20% of the electricity in the United States for over 20 years, with no emissions of carbon dioxide (CO2 ). France gets nearly 75% of its electricity from nuclear power, the highest proportion of any nation. Germany and Japan each got more than 25% of their electricity from nuclear power in 2010; though Germany shut down about half of its reactors, Japan temporarily shut down all of its reactors, and both are considering permanently closing down their reactors after the accident in Fukushima, Japan, in 2011. So nuclear power has been providing electricity for over 50 years and plays a major role in the energy mix for a number of countries. But nuclear power is also critically important for an energy future that will meet our electrical power needs with minimal production of greenhouse gases and benign effects on the environment. We must go back to the future if we want to make serious inroads into reducing greenhouse gases and global warming. To see why nuclear power is critical for the future, let’s begin our journey by touring a nuclear power plant. The Wolf Creek nuclear power plant sits on the flat plains of Kansas about 60 miles south of Topeka and 4 miles from Burlington, about 200 miles east of the wheat fields I farmed as a kid. A 5,090-acre lake filled with crappie, walleye, large and smallmouth bass, and other game fish provides cooling water for the reactor and also provides a fishing mecca for Kansans. The 10,500-acre site, including the reactor complex and the lake, has about 1,500 acres of wildlife habitat, and about one-third is leased to area farmers and ranchers. The plant itself takes up less than half a square mile. The lake provides habitat for waterfowl, as well as for bald eagles and osprey. It is hard to imagine that electricity for 800,000 people is generated in this pristine area of farmland and nature preserve.

Where Our Energy Comes From

Energy and human history go hand in hand. For most of the time that humans have been on earth, energy was used at a very low level, mostly by burning wood for cooking and warmth. This is still the case for large areas of the planet, especially in much of Africa and parts of Asia and South America. As human populations grew, forests were decimated to obtain fuel, resulting in the collapse of several societies (1). Coal was discovered in England in the thirteenth century and began to be used extensively beginning in the 1500s. Between 1570 and 1603, during the reign of Elizabeth I, coal became the main source of fuel for England (2). This was, not coincidentally, also during the time of the Little Ice Age, when there was a great need for fuel to keep warm. Coal transformed England, for better and for worse. The development of the coal-based steam engine by Thomas Newcomen in 1712, with further critical developments by James Watt and Matthew Boulton, led to the Industrial Revolution beginning in about 1780. Coal built England into the world’s most powerful country during the nineteenth century. At the same time, it brought about unbelievable pollution, which drastically shortened lives, and it led to child slave labor in factories and mines. Coal had been discovered even earlier in China and was being used for iron production in the eleventh century (2). Coal was discovered in Appalachia in the United States in the mid-eighteenth century and quickly became its most abundant source of energy. This led to the industrial development of the United States, the building of canals to transport coal, and the construction of railroads to connect the far reaches of the country. Wherever large sources of coal were found, societies were transformed. Coal was fine for running steam engines and cooking or keeping warm, but what people wanted desperately was a better source of light for their homes and businesses.