(Editor’s Note: This article was originally published on October 30, 2012.)
One week. In one week we shall wake up, go to school or work, and carve out fifteen minutes to participate in what has perhaps become the ultimate symbol of modernity: free elections. For months now we have been inundated with commercials, speeches, and debates all telling us what to do on this one day: the day we choose our next president.
This year’s campaigns have emphasized vital areas of interest like economic recovery, the national debt, and healthcare. However, many other important issues have fallen through the cracks. Among these is science policy.
The reason why is clear. We value science, but it just does not seem as pressing as other issues. In a recent poll conducted by the Yale Scientific Magazine, a majority of Yale undergraduates deemed science policy important (x = 3.43, on a ten-point scale) in determining their vote for president. Yet, when asked to rank science policy against other topics, science policy was consistently ranked as less important (x=6.23) than almost every other election topic. Moreover, a majority of Yale undergraduates replied that they believed themselves to be either “not very well informed” or only “somewhat well informed” about the current science issues facing America. This needs to change. Presented here are the underlying science, the current facts, and each candidate’s stance on the two science issues that surveyed Yale students regarded most important: alternative energy and climate change.
At the heart of every power plant is a spinning wheel, known as a turbine. In slightly more technical terms, every power plant produces electric current the same way: by rotating a loop of wire through a magnetic field. This technique is ubiquitous for all power plants, including coal, natural gas, petroleum, nuclear, hydro, wind, geothermal, and solar plants. It is only in how they spin this turbine that they differ.
Windmills let gusts of wind spin their massive blades, while hydropower plants (dams) use the force of flowing water to rotate turbines. All other types of common power plants — coal, natural gas, petroleum, nuclear, solar, geothermal — use the same technique to rotate their turbines: they boil water.
Each power plant boils water either by generating heat via an exothermal process (combustion for coal, petroleum, and natural gas; nuclear fission for nuclear) or collecting it from the environment (solar, geothermal). The heat from these processes is used to convert water into highly pressurized steam. This superheated steam, which can reach temperatures of 1,000 °F and pressures of 3,500 pounds per square foot, is then fed through pipes to a turbine, thereby spinning it. This flow of pressurized gas generates electric current for routine functions.
Despite their shared mechanism, not all power plants affect the environment equally. Fossil-fuel-burning plants (those that combust coal, petroleum, and natural gas) are environmentally harmful, producing vast amounts of carbon dioxide and significant quantities of other pollutants. Moreover, fossil fuels take millions of years to form and exist in limited quantities. Nuclear plants, on the other hand, produce only small quantities of waste (millions of times less by weight than coal combustion), but the radioactive waste they produce is highly toxic and persists almost indefinitely in waste dumps (it can take millions of years for even half of the waste to decay).
By greater contrast, hydro, wind, solar, and geothermal power plants have renewable sources and do not emit significant amounts of pollutants. These environmental considerations are important not only to maintain clean air, ensure sanitary water, and preserve nature but also to address and ideally resist the dawning realities of global warming.
A Look At The Numbers
Last year, the U.S. consumed 97.30 quadrillion kJ of energy. Assuming you consume 2,000 calories per day, that’s enough energy to ‘power’ you for the next 30,100,000,000,000 years.
The vast majority (82 percent) of this energy comes from burning fossil fuels. Petroleum (36 percent), natural gas (26 percent), and coal (20 percent) make up nearly all of this.
In the U.S., only 16.6% of the total energy used comes from “clean” energy sources. Of this, 63.6% comes from nuclear power plants, 24.4% is from hydropower plants, 9.0% is from windmills, and the rest (3.0%) is a combination of solar and geothermal.
The U.S. lags internationally in the use of alternative energy. In 2010, for instance, over 45% of German electricity came from either nuclear or renewable sources.
While both Mitt Romney and Barack Obama center their energy policies on achieving energy independence by increasing domestic production, they differ in how they want to achieve this goal.
Broadly speaking, the Republican platform aims to decrease oil imports by letting the private sector develop the U.S.’s own natural reserves. There are undeniably ample quantities of fossil fuel within the U.S. (237 trillion tons of coal, 219 billion barrels of oil, and just under 2 trillion cubic feet of natural gas), although these supplies are not unlimited. Overly aggressive exploitation of these reserves could cause environmental damage, and a continued dependence on coal and natural gas power plants would exacerbate global warming.
By comparison, the Democratic platform is to actively encourage the development of alternative energies while moving the emphasis away from fossil fuels. This approach is costly; nuclear power plants are five-to-ten times more expensive to build than coal plants, though their long-term operating costs are comparable.
For each party, more detailed plans, available online (see Further Reading), are both more nuanced and more convergent than is commonly acknowledged. The most important questions we face do not ask “which one,” but “to what degree.”
By this point, we’ve all heard of climate change. There is a lot of carbon dioxide in the atmosphere (390 ppm). There used to be way less before industrialization (<300ppm). We keep producing it (4.76 metric tons per person globally). Fossil fuels are to blame (29 additional gigatons of CO2 per year). The earth gets hotter (0.014°F per year). Oceans rise, polar bears drown, and Norwegians go to the beach. These facts are understood, but the underlying science is far more interesting and rarely discussed.
The greenhouse effect underlies most of the science behind global warming. Gases in the atmosphere absorb the sun’s rays to varying degrees, causing the amount of heat retained (and therefore the temperature) to vary based on gas concentrations.
Imagine two planets: one without an atmosphere (like Mars) and one with an atmosphere (like Earth). On the Mars-like planet, the sun’s rays travel directly to the rocky surface, where they are absorbed and then reflected directly back into space. On the Earth-like planet, the rays cannot travel directly to the surface because they must pass through the atmosphere first. Atmospheric gases absorb radiation and emit it in all directions, so some of the radiation is ‘trapped’ within the atmosphere. This effect simultaneously slows the rate of cooling of the planet and increases the amount of heat absorbed. Both of these raise the average temperature. This effect is not subtle; if Earth lacked an atmosphere, it would be around 60°F colder than it is today.
To fully understand global warming, we must also acknowledge that not all gases are equal; some gases absorb the sun’s rays readily, while others don’t. Those gases that easily absorb solar energy are known as greenhouse gases. The more greenhouse gases there are in the atmosphere, the more heat the earth retains and the warmer the planet will be. This, in short, is global warming.
Each year, the U.S. produces 5,500,000 tons of carbon dioxide. Nearly all of this comes from burning fossil fuels: 32 percent comes from coal plants alone, 30 percent comes from transportation, 17 percent comes from heavy industry, and 7 percent comes from non-coal combustion power plants. The remaining 14 percent comes from various sources.
Compared to other modernized countries, the U.S. does poorly. We are the second largest producer of carbon dioxide, trailing only China. And while U.S. emissions are decreasing, we remain behind the curve.
Let’s clarify one aspect right away: both candidates acknowledge global warming as real and influenced by man. They differ, however, in the degree to which they believe man has caused global warming and how they wish to address it.
As previously discussed, the same principles that applied to alternative energy also apply to global warming. Republicans tend to prefer a more economical, less environmental approach, while Democrats prefer a more environmental, less economical approach. While Barack Obama favors an active approach to reducing carbon emissions, Mitt Romney views such a stance as a hindrance to the economy and instead prefers loosening environmental regulations.
One Week, One Click
On Tuesday, November 6, 2012, we will elect our next president. With alternative energy policy and the global warming just small pieces of the increasingly complicated and scientifically involved challenges facing us, Thomas Jefferson’s words have never been more true: “Democracy demands an educated and informed electorate.” Today more than ever, it is vital to be aware, to know the issues, the facts, and the science behind the choices facing our nation, and to voice your opinion accordingly. The information is out there. In fact it is more accessible now than ever before, waiting just a click away.
About the Author
John Urwin is a junior Molecular Biophysics and Biochemistry major in Jonathan Edwards College. He is a Layout Editor for Yale Scientific Magazine and has worked in Professor Colón-Ramos’ lab studying nervous system development in C. elegans.
“Energy, Climate Change, and Our Environment,” The White House–President Barack Obama, March 2012. https://www.whitehouse.gov/energy