Museum of Science

On March 11,  we took a field trip to the Museum of Science in order to see four exhibits that show information related to what we are learning in class. These exhibits were “Catching the Wind”, “Conserve @ Home”, “Energized!” and “Investigate!”.

The first exhibit I visited was “Catching the Wind”, and it was all about wind and wind turbines. We have been using wind power for thousands of years, for examples, we used windmills to grind grain around the year 500 A.D., we used wind power to sail, and in the modern day, we used wind power to generate electricity.

the picture above shows all of the components inside a wind turbine, which is exactly what we learnt from the class. As the wind turns the blades, the mechanical energy goes to the electric generator, which generate electricity for us to use. There are five wind turbines on the Museum’s roof, and one of them generates 2,218 kWh and saves 2,706 lbs. CO2 emissions annually.

The second exhibit I went was “Energized”, and this exhibit showed us where energy came from. Unfortunately, As we were promoting renewable energies, only 8% of energy came from them, and 83% of our energy use was still account to fossil fuels. The exhibit also summarized pros and cons of some major forms of energy, such as fossil fuels, hydropower, nuclear, solar and wind. There were also some hand-on activities available to visitors, and on of them was that the visitors should power the city using combination of difference kind of energy without putting too much emission to our environment.

Next, I went to the “Conserve @ Home”, and this exhibit was all about what we could do to conserve energy, save money and protect our environment in our daily life. One of the fact that shocked me was that using rechargeable battery can save about 800 disposable batteries. And I though from now on, I should use rechargeable battery instead disposable batteries. Because it helped save energy and material to make disposable batteries.

Then I saw a family was in front of a hand-on activity called “Turn Your Energy Into Light”, and as the boy turning the wheel around, the LED bulb lighted. But after the father switch to incandescent bulb, the boy could barely light the light bulb. After they gone, I examined the site, and found that incandescent light bulb actually required 40 watts of energy to light up, where LED bulb only need 8 watts of energy.

The last exhibit I went was “Investigate!”, and there were full of kids because stuffs there were actually very fun. I was drawn into a toilet, which would told people how the toilet worked after activity. But the kids were flushing the toilet on and on, so I had to go to other place. The second thing that got my attention was “Experiment with Drains”. It was about what affect the direction of the water spiral down a drain. And like some of people believed, I though it depended on the hemisphere and the spinning of the Earth. But after doing the experiment, I found that the water did not spiral if I did not flick the water with a stick. And I was always wrong about this. Then I began to think about why did it happen, and I though it was probably about the direction of force applied to the water, and the force may still be there even if the water was calm.

I left the Museum at one p.m. after visiting some other exhibits because I had class later that day. Overall, it was a very nice field trip to visit the Museum of Science, and I also learned a lot during this visiting. From the things that connected to our course, to conserving energy and protecting environment in our daily life. And also to discover the fact that I was always wrong about.

Nuclear Disasters

The first thing that comes to my mind about Nuclear Disaster is the Chernobyl nuclear reactor disaster. The Chernobyl disaster was a catastrophic nuclear accident that occurred at the Chernobyl Nuclear Power Plant in the town of Pripyat, in Ukraine, which was under the direct jurisdiction of the central authorities of the Soviet Union. On 26 April 1986, a power surge during a test procedure resulted in a criticality accident, leading to a powerful steam explosion and fire that released a significant fraction of core material into the environment, resulting in a death toll of 56 as well as estimated 4,000 additional cancer fatalities among people exposed to elevated doses of radiation. As a result, the city of Chernobyl was largely abandoned, the larger city of Pripyat was completely abandoned, and a permanent 30 kilometers exclusion zone around the reactor was established. The main cause of the disaster was the poorly design of the plant, and also the disqualification of the control rods.

The other nuclear disaster is the Fukushima Daiichi nuclear disaster, it was an event that happened in Japan in March of 2011. A major earthquake triggered a 15 meter tsunami that disabled the power supply and cooling of three Fukushima Daiichi reactors and caused a nuclear accident. Within the first three days all three cores were largely melted and high radioactive releases occurred over the next three days but after two weeks they were stable with water addition and by July they were being cooled with recycled water from a new treatment plant. In addition to having to cool down the reactors, it was essential to try to prevent the release of radioactive materials, in particular the contaminated water leaked from the three units.

The nuclear disasters have so much negative impacts on both organisms and environment that we should always think about how to make them safe before we build a nuclear power plant. One way that to make sure that is safe is to check the design of the power plant, so have scientists from other countries to work together to see if that design actually works. And then, we should also make the outer cell to be tough enough, so if the reactor explodes we could still be able to minimize the danger.

https://en.wikipedia.org/wiki/International_Nuclear_Event_Scale#Level_7:_Major_accident

http://www.world-nuclear.org/information-library/safety-and-security/safety-of-plants/fukushima-accident.aspx

https://en.wikipedia.org/wiki/Chernobyl_disaster

Pandora’s Promise

The Pandora’s Promise is a movie that talks about whether to use nuclear power. It opened with a scene involving people protesting nuclear power and really works to show that while it continues to be a controversial issue in the world today. Nuclear energy is one of the cleanest way of generating energy, but it has many negative side. Many people feared about nuclear energy, because it connects to nuclear bomb, and also those disasters in the history.

Throughout the movie, there are different nuclear disasters presented that really show the devastation that can occur as a result of not properly handling nuclear power and the importance of constantly working as efficiently, precisely, and safely with nuclear energy as possible. They provided a lot of important information that is very convincing in proving that nuclear energy is a viable option for a better, greener future and that we need to get rid of the stigma of danger and focus on the safe and clean energy source that nuclear can be.

Iceland and Geothermal Energy

During the course of the 20th century, Iceland went from what was one of Europe’s poorest countries, dependent upon peat and imported coal for its energy, to a country with a high standard of living where practically all stationary energy is derived from renewable resources. In 2014, roughly 85% of primary energy use in Iceland came from indigenous renewable resources. Thereof 66% was from geothermal.

From the picture above, we see that among all of the energy from geothermal, 43% of them goes to space heating, and 40% of them goes to generating electricity. In sum, these two sectors distributed over 80% of the nation’s geothermal energy usage, because electricity is the most useful energy for us to use, and space heating is also important for people to live in a cold environment.

This is a geothermal vertical loop system, basically, the liquid or air on the pipe gets heated from our earth, and then goes back to our house by using a heat pump. There are also some other kinds of loop, for examples, horizontal loop, slinky loop, pond loop and well loop. Which are installed depend on the situations.

Generating electricity with geothermal energy has increased significantly in recent years. As a result of a rapid expansion in Iceland’s energy intensive industry, the demand for electricity has increased considerably. From 1970-2013. The installed generation capacity of geothermal power plants  totaled  665 MW_e in 2013 and the production was 5.245 GWh, or 29% of the country’s total electricity production.

The idea of generating electricity from geothermal energy is similar to getting the heat. We just need to install a turbine and generator on the ground. And we can have the turbine spin through the steam on the lope and generate electricity from the generator.

Right now, Iceland is implementing The Iceland deep drilling project, which is a long term project focusing on harness geothermal energy below the several kilometers to reach hydrothermal fluids at temperatures ranging from 450°C to ~600°C. And with the energy, they will be able to generate much more electricity to use in the future.

References：

http://www.nea.is/geothermal/

http://en.wikipedia.org/wiki/Geothermal_power_in_Iceland

http://environment.nationalgeographic.com/environment/global-warming/geothermal-profile/