Stories tagged nuclear energy

Jul
15
2010

“…Welcome back, class. Please hand in your essays on the scientific fundamentals of phosphorus-driven eutrophication in the Gulf of Mexico, and note that our exam covering chapter eight, the Biogeochemistry of Acid Mine Drainage, will take place next Tuesday. Today we will be covering fluid bed catalytic oxidation, hazardous waste landfill leachates, and NIMBY. But, first, let’s take attendance: Bueller?... Bueller?... Bueller??”

Say what? “Nimby?” Girl, puh-lease! He just made that up… didn’t he??

It wasn’t long into my undergraduate stint as an Environmental Science major that I came across the word, “nimby.” Actually, it’s not a word at all. It’s an acronym, N.I.M.B.Y., standing for “Not In My BackYard,” that captures an important public attitude that affects environmental policymaking.

NIMBY explains many people’s attitude towards environmental policies, capturing sentiments like,

“That’s such a cool and important idea! As long as it’s not actually happening in my community, that is.”

“Whatever. I don’t care so long as I don’t have to see it everyday.”

NIMBY: Yuck.  Who wants to look out their bedroom window and see a mountain of trash?  Not these guys.
NIMBY: Yuck. Who wants to look out their bedroom window and see a mountain of trash? Not these guys.Courtesy The Voice of Eye

Think About It

Do you like having your trash removed from your home? Most everyone does. But, would you like having a landfill in your backyard? Almost nobody does. This is the classic example of NIMBY. Nearly everyone likes having their trash collected from their property and transported out of sight and smell, yet someone, somewhere has to live beside a mountain of trash. As long as we’re not the ones living across the street from the landfill, most of us are satisfied with this method of garbage disposal. The same idea goes for wastewater treatment facilities as well.

Another classic example is nuclear power. Some people support nuclear power as an inexpensive and “clean” alternative to fossil fuels like oil and natural gas. However, the construction, maintenance, and decommissioning of a nuclear power plant poses risks and creates radioactive waste. Whether or not you think the risks and waste production are acceptable consequences depends largely on your proximity to the plant and/or ultimate disposal site for the nuclear waste.

A recent example of NIMBY is occurring in California this summer as covered in Green, a New York Times blog. In a valley near Santa Clara, Martifer Renewables canceled their plan to build a hybrid solar power plant. Set on 640 acres of agricultural land, the plant was supposed to produce electricity by solar power during the day and biomass burning by night. How sweet is that?? A 24-hour source of renewable energy! The California utility PG&E thought it was a great idea too and signed a 20-year power purchase agreement for 106.8 megawatts, which became part of their energy portfolio. PG&E must obtain 20% of its electricity from renewable resources by December of this year and another 13% (for 33% total) by 2020, as mandated by California state energy goals. Now that the project is canceled, PG&E will have to look elsewhere for sources of renewable electricity or risk missing their mandated targets.

Regarding the canceled project, Martifer executive, Miguel Lobo, wrote in a June 17th letter that,

“We were not able at this time to resolve some of our issues regarding project economics and biomass supply amongst other things.”

What Lobo was likely referring to are the complaints of local residents and regulators who contested several aspects of the project. Chief amongst the complaints was the around-the-clock operation made possible by burning biomass. What exactly were they so excited about? Noise, waste, and air pollution – all realities of energy production, yet things we’d rather not experience ourselves. In short, NIMBY.

Alright, so what?

Now that I’ve opened your eyes to the existence of NIMBY, you might be wondering how it influences environmental policymaking. The easiest answer is that environmental policymakers seek to find a balance between the conflicting desires for new technology like this power plant and local opposition and the NIMBY attitude. Often both sides make compromises and projects move forward on a slightly different path than previously proposed. However, as in the California case of Martifer Renewables, occasionally a project is completely scrapped. Other times, the project proceeds as originally planned. Which of the outcomes occurs depends largely on the organization and influence of the local opposition. In turn, this often raises issues of environmental or eco-justice.

Clearly our modern society cannot exist without landfills or wastewater treatment facilities as smelly and unsightly as they may be. Whether or not nuclear or other renewable energy power plants are equally necessary today is debatable, but it’s not hard to imagine a future in which they will be. If no one agreed to have these facilities in their community, life as we know it would be very different. This begs the question: how do you think policymakers should balance the needs of society at large against the NIMBY attitude of locals?

Jan
11
2010

Radioactive Peace: With all countries taking from a nuclear fuel bank, no one country will have to enrich its own uranium.
Radioactive Peace: With all countries taking from a nuclear fuel bank, no one country will have to enrich its own uranium.Courtesy kso
Talk of nuclear power has been brought back into the spotlight, especially after the discovery of Iran’s uranium enrichment plant last September. A solution to the debate about whether countries should even have the capability of enriching uranium (the process required for attaining both nuclear energy and nuclear weapons) was posed more than 50 years ago by President Eisenhower. Eisenhower suggested that various countries should allocate uranium from their stockpiles for peaceful pursuits (i.e. nuclear energy). At the time it wasn’t received very well, but a recent BBC article reported that this vision has been renewed. As of November of last year, the United Nation’s International Atomic Energy Agency (IAEA) successfully negotiated with Russia to store 120 tonnes of nuclear fuel in a plant in Angarsk (a city in the south central-ish part of Russia). In 2010, similar arrangements are said to be made with Kazakhstan. The idea is to get developing countries that are thinking about using nuclear energy in the future to join in this program, eliminating their need to enrich their own uranium.

All of this got me thinking about how nuclear energy actually works. It turns out that nuclear power plants are not that different from regular coal-burning power plants. Both plants heat water to produce pressurized steam. This steam then drives a turbine, which spins a generator to produce electricity. The only difference between the plants is how the water is heated. Coal-burning plants…well, burn coal (fossil fuels) to produce the heat, while nuclear plants rely on nuclear fission. This is where nuclear power gets really cool!

So atoms are made up of protons, neutrons, and electrons; protons are positively charged, neutrons carry no charge, and electrons are negatively charged. Atoms have an equal number of protons and electrons (making the atom, itself, electrically neutral), but the number of neutrons can vary. Atoms of the same element with a different number of neutrons are called isotopes. The isotope of uranium that is needed for nuclear fission, and therefore, nuclear energy, is Uranium-235. This isotope is unique because it can undergo induced fission, which means its nucleus can be forced to split. This happens when a free neutron runs into the nucleus of U-235. Nuclear fission
Nuclear fissionCourtesy wondigama
U-235 absorbs the neutron, becomes unstable, and breaks into two new nuclei. In the process, two or three neutrons are also thrown out. All of this happens in a matter of picoseconds (0.000000000001 seconds)! The neutrons that are released in this reaction can then go and collide with other on-looking U-235 atoms, causing a huge chain reaction (much like this). The amount of energy released when this happens is incredible- a pound of highly enriched uranium has about the same energy as a million gallons of gasoline. This energy comes from the fact that the products of the fission (the two resulting nuclei and the neutrons that fly off), together, don’t weigh as much as the original U-235 atom. This weight difference is converted directly into energy. It’s this energy that is used to heat the water that creates the steam, which turns the turbine that spins the generator, that produces power in the nuclear reactor that Jack built.

On the plus side, with nuclear power there wouldn’t be a reliance on fossil fuels. Nuclear power plants are cleaner because they don’t emit as much carbon dioxide as traditional coal-burning and natural gas plants. However, there are some downsides as well. Mining uranium is not a clean process, transporting nuclear fuel creates a risk of radioactive contamination, and then there’s the whole issue with what to do with the still-dangerous nuclear waste once the fuel has been used up.

Whether or not we should increase our nuclear power program is still debatable, but one thing I do know is that the science behind it is fascinating!