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Why don't we just swich to all nuclear power? What are the negatives? (Besides it is dangerous)
Do any scientists disagree that humans are in fact the cause of Global Warming, and that global warming is due to high CO2 levels?
Answer 1:

Actually, nuclear power plants these days are not that dangerous to operate, or even live near! The worst part (regarding danger) is what to do with the waste! The used up radioactive material is dangerous for thousands of years, so it is important to keep it away from living beings (you, me, animals, and plants). We already have a lot of nuclear waste, and switching to all nuclear would build up waste much more rapidly!

Another reason we can't just switch to nuclear power is that we need a PORTABLE FUEL, like gasoline for cars and airplanes. If we use nuclear energy to generate electrical energy (in power lines) we cannot directly use that in our cars, for example, like we do with gasoline. We COULD use the electrical energy from a nuclear power plant to charge batteries, but currently batteries are not very efficient and not long lasting enough to replace something like gasoline. There are other options to electrically charging automobiles, but they are still under development.

I think all ALMOST ALL scientists agree that we are increasing the amount of CO2, this is undeniable.

Now, what the CO2 is actually doing to our environment can be debated. MOST scientists agree that the higher levels of CO2 we are creating are increasing the global average temperature. But, the heating cycle of the earth is VERY complex (try to predict the weather this day in 10 years!), but scientists do try to model (or calculate) what the CO2 will do to our planet and the changes predicted are basically an increase in temperature and bad news for much of the life on our planet.

Any change brought on by increasing CO2 is likely not something we want to deal with as people. Any drastic climate change will likely put millions or more of peoples lives in danger.


Answer 2:

You have some great questions.One of the big negatives about nuclear power is concerns over safety. Nuclear power plants are very expensive to build and if enough people are scared of them, it's very difficult to get enough money to build one or find a location that people won't mind. The main reason we don't use nuclear power plants for more of our energy needs is that the technology is not advanced enough yet. Nuclear power plants don't use up all the radioactive material in their fuel rods, so there's a big problem of figuring out what to do with the nuclear waste. Sometimes they're stored deep inside mountains, but there's only so much space to do that. Until nuclear engineers can figure out a better way to store the waste or a way to make nuclear power plants more efficient so there's not as much waste, we can't just all switch over to nuclear power.

As far as global warming goes, while most scientists do believe that it's caused by increased CO2 levels resulting from human activities (I included), there are a few scientists who disagree. Here's a link to an article on wikipedia that talks about some scientists who disagree, and why they disagree.

click here
Scientists_opposing_the_mainstream_scientific_assessment_of_global_warming

Answer 3:

He, good one. This is a politically loaded subject, and unfortunately when politics and money get into the equation, the science has an unfortunate tendency to get swept under the carpet. However...

First question: nuclear power has two major drawbacks.These are (1) the nuclear waste products that it generates, and (2) the risk of a nuclear meltdown. (2)is minor; it used to be a problem, but better technology and modern design of nuclear reactors and better training of the engineers who operate nuclear reactors has basically eliminated this threat. Nuclear meltdowns can still happen, but unlike Chernobyl the reactor core itself would not be exposed to the environment, so all of the radioactive debris that would result from such an event would be contained within the reactor and easily cleaned up. The cleanup would still be a messy business and an expensive slip-up, since you would need to replace the entire reactor and until then you're one power plant short of electricity, but environmentally at least it's not really a problem anymore. The nuclear waste products of normal reactor function, the spent fuel rods, are more of an issue. You have to put them somewhere they will not contaminate the environment. There are several strategies for doing this, either bury them where they will not get out (difficult), or holding them where we can keep an eye on them (although this stuff won't decay down to safe levels for longer than the lifespan of any human civilization...). This is more of a sticky issue. Personally, I like the "let's keep an eye on them" strategy - radioactive waste causes mutations and cancer and whatnot, which is bad for individual humans and thus bad for civilizations but not bad for the species as a whole, so if civilization goes down and we can't keep watch anymore, then it's our own fault.

The other reason why nuclear power isn't used extensively in the United States is political: due to the threat of nuclear annihilation during the Cold War, a lot of Americans are regarding anything nuclear as suspect or evil. What they don't realize is that the Sun is nuclear, and actually is the source of far more radioactivity in our lives than nuclear power plants, even in countries where nuclear power is the norm, e.g. France.

Second question: yes, scientists do disagree on whether we humans are causing global warming. The scientists who are of the opinion that humans probably are not the cause of global warming are in the minority, but they're there, and science is not a democracy. The simple fact is that the Earth's climate is an immensely complicated system with a whole lot of feed backs that we humans at this time simply do not understand. CO2 is a greenhouse gas, and nobody argues that the elevated levels of CO2 in the present day are our doing, but the fact is that CO2 is a very weak greenhouse gas, much weaker than water vapor, which is not only far more powerful than CO2molecule-for-molecule but is also far more common.Water vapor and CO2 together affect the world's climate as a result of a positive feedback loop, but the greenhouse effect isn't the only thing affecting climate. Most climatologists rely on computer models to predict weather at different levels of CO2, and most of them assume an approximate 4-foldamplification of any change in climate caused by changing CO2 levels as a result of a corresponding change in the level of water vapor.

Unfortunately, these models are inadequately tested; we have not been altering the levels of CO2 in our atmosphere ourselves for long enough to be able to really observe the effects and control for all of the other factors influencing the Earth's climate, such as changes in the brightness of the Sun or subtle changes in the flow of currents in the oceans. The geologic record does show that climate in the past has a very close association with CO2 levels, but that in itself does not prove anything because CO2 becomes less soluble in water with higher temperature, so if climate warms, more CO2 will come out into the atmosphere anyway. The vast majority of climates cientists I would say are of the opinion that increased levels of CO2 due to human activity are warming the planet, but the question is how much.There is disagreement even on the extent to which the Earth is warming up, and even then, there are other possible causes of warming such as the aforementioned and also very difficult to measure change in the brightness of the Sun.

The money problem also enters into this, sadly: lobbying groups, both pro-fossil fuels and pro-left wing environmentalism, are funding scientists to do research on the question, and they know what results they want the scientists they fund to come up with. Asa re

Answer 4:

These are the great questions that many scientists and lawmakers ask too! There are no simple answers, but here hopefully is some helpful information.

The earth warms and cools in cycles over long periods. For the last 8,000 years or so, the earth has been relatively warm and stable. The earth retains much of its heat by having "green house gases" in the atmosphere. These gases, including carbon dioxide, methane, and even water vapor, can have natural sources. However, humans, especially since the beginning of the Industrial Revolution (when many factories starting burning fossil fuels) have been added huge amounts of greenhouse gases into the atmosphere, and have caused the loss of forests,which also increases carbon dioxide.

It is known that green house gases cause warming, that humans have increased that atmospheric carbon dioxide to levels greater than they have been for over 400,000 years!, and the global temperature is climbing faster and higher than can be explained just by natural cycles. Scientists agree that human production of green house gases is having a massive effect on the global climate. Scientists do have different theories about the ultimate outcome of the climate change caused by humans, but none of the scenarios are very positive.

There are some possible ways to reduce the use of fossil fuels (coal, gasoline) are to get energy in "alternative" ways. Energy can be harnessed from the wind, or from the solar energy of the sun. Another way to create energy is by harnessing the energy released by the combination of two atoms of heavy elements, or "nuclear fission". This energy can be used to heat water to generate electricity. This process is done in nuclear power plants. The United States gets 20% of its power from these kinds of plants, and countries like France get 80% of their power this way.

The problems with nuclear power include finding a way to get rid of the radioactive waste that is produced and the possibility of a power plant accident. If we can develop a safe way to dispose of the waste, and can make sure that nuclear power plants will not release their material into the environment, nuclear power could be a good way to reduce greenhouse gas emissions. The earth needs the young minds of science coming up with more and better ways of making energy; maybe that will be you!


Answer 5:

Switching everything to nuclear power is not as easy as it sounds. While it is true that our dependence on fossil fuels is very high, and does not seem to be decreasing, it is wise to invest in alternate energy sources, nuclear power being one of them. First off, it will take a huge governmental budget to begin constructing these facilities, money that the government may wish to allocate otherwise based on its political agenda and its priorities. Furthermore, a very large number of families depend on the oil industry for their livelihood. So to "just switch" to nuclear power is not the right way to make the shift from fossil fuels to alternative energy sources, even though a slow shift away from fossil fuels is in my opinion a very important step that all countries should make.

Global warming is caused by many factors, including the release of greenhouse gases into the atmosphere, carbon dioxide being only one of those greenhouse gases. Scientists do not disagree that increasing levels of carbon dioxide are one of the main causes (and NOT the only one) of global warming, nor do they generally disagree that humans have a hand in it; what scientists disagree on is the extent to which humans are responsible, i.e. their level of contribution to global warming based on the rate that they release carbon dioxide (and other greenhouse gases) into the atmosphere versus the carbon dioxide released by natural earthly occurrences.


Answer 6:

Great questions.

There are two main obstacles for nuclear power in the U.S. First, designs for nuclear reactors that are "cheap and easy" are also the most dangerous designs. Instead, you need to design reactors that withstand the most stupid mistakes people can make, because everybody makes mistakes. The reactor should also survive people "testing" a reactor by turning off all the safety features, which was what happened at Chernobyl. There are modern reactor designs called Pebble Beds which can run just fine even if all the cooling water were to drain out, for example. The radioactive fuel (uranium) is trapped inside ceramic beads, so the rate of fission is controlled: it can't explode and can't melt down. It is also much safer to transport and store the used uranium this way. There is a Canadian design (CANDU) which is similarly safe. Modern reactors are being built in France, Germany, China, Japan, Canada, India, and many other countries.

The second main obstacle is emotional, not technical. Many people don't understand the difference between nuclear power and nuclear weapons, so they're afraid of anything with the word "nuclear." In fact, the largest expense for nuclear power plants is not the building of the power plant, but getting through all the regulations that people impose because they're afraid. Many safety regulations are good, but this process can take up to 20 years. Imagine buying a new car now and being told you couldn't drive it for 20 years! That is why no new reactors have been built in the U.S. for 25 years. Unfortunately, coal-burning power plants dump hundreds or thousands of times more radioactive waste into our air and soil than a nuclear reactor would. There is a little bit of uranium in coal, and that uranium goes into the air when the coal is burned. Some environmentalists have recently begun pushing for more nuclear power just for this reason.

Your second question, about global warming, is tricky. Science works best when there are disagreements and a wide range of ideas and opinions. Everyone looks at the same data from an experiment and tries to come up with a good explanation. They say things like, "Your explanation seems to make sense, but look at it this way instead..." The best explanations are the ones that can predict the results of future experiments.

Unfortunately, with global warming, we can't run the "experiment" multiple times to know for sure who is right. Probably everyone has some mistakes in their ideas. Even so, an overwhelming majority of scientists who study global warming believe that: 1. it is occurring, 2. it is man-made (not merely a natural variation), and 3. CO2 is a major contributor to global warming (although not the only one). The only real debate is *how quickly* the global warming is occurring, and what the effects will be. Unfortunately, there are extremists on both sides of the debate, and they both try to claim "Science proves..." Few scientists believe it will be as bad as recent movies have shown. But most scientists think global warming should be slowed and, if possible, stopped. It might be very expensive and difficult to completely stop global warming (everyone likes to drive!), so there are always some people who want to pretend it doesn't exist at all. Read as much as you can from different perspectives and keep an open mind. The best scientist is one who is ready to believe they may be wrong.

Best wishes...


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