Month: November 2015

Stirling Heat Engine, Peltier Device, and Iceland

The Stirling engine, which is known for its high efficiency, is a machine that uses heat energy to generate power. Rev. Robert Stirling invented it in 1816 because he was looking for an alternative energy source that was safer than steam. A Stirling engine works in a four-step process, compressing cold gas, heating the gas, expanding the hot gas, and cooling the gas. This process is repeated over and over again. One of the positive effects of this type of engine is that it doesn’t generate any emissions. One of the unique features of this type of engine is the fact that it is a closed cycle, external combustion engine. This means that it uses a fixed amount of fluid to run and other gases can also be used. This feature allows the engine to run on any kind of fuel such as solar, nuclear, or biological waste. There are many different types and versions of Stirling engines and they mostly differ in the number of cylinders they use to generate power. One of the downsides of this type of energy is the fact that it is large for the power that it produces which limits the range of uses to low power application. However, specific power can be improved by use of higher gas pressures.

Peltier devices, also known as thermoelectric coolers, use the Peltier effect to move heat. These devices typically produce heat from 40C to 70C. Some of the more developed versions of these devices can also transfer heat from one place to another. The concept of Peltier effect goes back to 1834. All electric current is supplemented by heat current based on the Joule heating theory, Peltier realized that when electric current passes across the junction of two dissimilar conductors, there is a heating effect that is not based solely on Joule hearting.

When two conductors come to electric contact, electrons move from the one where electrons are less bound to the one with more electrons. The reason behind this difference is the Fermi level between the two conductors. When two conductors with different Fermi levels make contact, electrons flow from the conductor with the higher level of electrons until the two conductors stabilize in value. In other words, it brings heat from one side to the other side while one side gets cooler and the other side gets hotter with the consumption of electric energy. The current passing across the junction can result in a temperature incline. This type of device can be used for both heating and cooling and can also be used as a temperature controller. This device has the same disadvantage of the previous device in a way that it has high costs with low energy production.

  

 

 

References:

 

Active Cool. “Understanding Thermoelectric Cooling.”  N.p., n.d. Web. Nov. 2015.

 

http://www.activecool.com/technotes/thermoelectric.html.

 

“Battery and Energy Technologies.” The Stirling Engine. N.p., n.d. Web. 02 Nov. 2015.

 

http://www.mpoweruk.com/stirling_engine.htm.

 

Japan Steel Buys Stake in Icelandic Geothermal Power Venture — Alexander’s Gas and

 

Oil Connections. N.p., n.d. Nov. 2015.

 

http://www.gasandoil.com/news/europe/e447f4815fede2edb36a05b568762078

 

“Peltier – Thermoelectric Cooler Modules – TE Tech Products.” TE Tech Products. N.p., n.d. Web. Nov. 2015. http://tetech.com/peltier-thermoelectric-cooler-modules/.

Renvall, Matts. “Six Stirling Powered Cleantech Solutions from Scandinavia.”Six Stirling    Powered Cleantech Solutions from Scandinavia. N.p., 07 May 2011. Web. 01             Nov. 2015.

 

 

 

 

 

 

Fukushima Daiichi Nuclear Disaster and Japan’s New Energy Strategies

In March 2011, Japan suffered an earthquake with the magnitude 9.0 that led to several tsunamis that disabled the power supply and cooling of three reactors at the Fukushima Daiichi nuclear site. The earthquake was centered 130 kilometers offshore the city of Sendai in the eastern coast of Honshu Island which consists a major part of Japan. 11 reactors were working at the time of the earthquake and they all shut down once the earthquake hit. However, three reactors were not able to handle the tsunami that followed the earthquake. All three reactors melted in the first days of the incident and four other ones were declared to have been damages. The accident was rated as a 7 on the INES scale, mainly due to high radioactive discharges. More than 80,000 residents had to evacuate their houses for the fear of radiation. Unfortunately, it was recently confirmed that the Fukushima Nuclear Site contains radiation-related cancer. Through the two weeks following the incident, the three reactors became stable with water additions and by the summer were being cooled by a new treatment plant. In addition to cooling, the major concern of the nuclear site was to stop the contamination and spread of radioactive water into other parts of the area. There have been no sicknesses or deaths reported that were direct results of radiation. However, over 1000 deaths could have been prevented in the evacuation process if the government allowed early return.

This catastrophe created major hazardous environmental and life threatening problems for the area of the nuclear site. It also forced the country to come up with alternative energy solutions because nuclear energy provided one third of the country’s electricity. Japan does not have many natural resources such as oil, coal, or natural gas and has to import them with high costs from other countries. One of these new strategies is wind energy. Being an island nation, Japan seems to be conveniently located in the route of strong wind currents during the typhoon season. In fact, after the Fukushima disaster, the government approved a massive budget plan for developing and improving wind power energy in Japan. In addition to wind power energy, Japan is investing in other forms of renewable energy such as solar, biomass, small hydro, and geothermal. The government is trying to create incentives by subsiding the renewable energy and conservation industries. The government has also set a tentative 40-year closing out deadline for many of the nuclear reactors. This plan is tentative because the government cannot afford to close down the reactors permanently which will could result in a $55.9 billion loss of power companies just this year. Since the industry is highly regulated, the government cannot afford to have the power companies go bankrupt.

 

Resources:

DeWit, Andrew. “Japan’s Remarkable Renewable Energy Drive-After Fukushima. 05        Nov. 2015. http://japanfocus.org/-Andrew-DeWit/3721/article.html

“Post-Fukushima Japan Turns To Wind As Solution For Energy Crisis |     OilPrice.com.” OilPrice.com. N.p., n.d. Web. 05 Nov. 2015.             http://oilprice.com/Alternative-Energy/Wind-Power/Post-Fukushima-Japan-          Turns-To-Wind-As-Solution-For-Energy-Crisis.html

Tabuchi, Hiroko. “Japan Sets Policy to Phase out Nuclear Power Plants by 2040.”The     New York Times. N.p., 14 Sept. 2012. 27 Oct. 2012.             <http://www.nytimes.com/2012/09/15/world/asia/japan-will-try-to-halt-nuclear-   power-by-the-end-of-the-2030s.html?pagewanted=all&_r=0>.

“World Nuclear Association.” Fukushima Accident. N.p., n.d. Web. Nov. 2015.

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

 

Museum blog

For one of our classes, we headed off to the Museum of Science to explore different exhibitions and get a better understanding of contemporary science. As a group, we explored a variety of scientific displays such as catching the wind, energy innovations, mechanical energy, and renewable and nonrenewable energy. While all of the exhibits were fascinating, one particular one stood out to me.

The tradeoff exhibit was an interesting one because it explained where our main source of everyday energy comes from. It demonstrated how there are seven sources of energy: wind, solar, hydropower, biomass, coal, nuclear power, and natural gas. Personally, I was not familiar with the specifics of renewable and nonrenewable energy. However, this exhibition gave me a clear understanding of different sources. For instance, the Catching the Wind exhibit demonstrated the mechanics of wind turbines and how they generate electricity. Wind turbines work in a different way than the other devices that generate energy. The reason why wind turbines are in the shape of high towers is to generate the most energy and take advantage of faster and less turbulent wind. Wind turbines generate energy using the wind. The wind turns the blades that are located on top of the device and connected to a generator. This process is repeated and electricity in generated. It also explained what trade-off we make in choosing a specific energy resource. It was interesting to see that the Museum itself has conducted its own case study regarding the wind turbines that are used in Massachusetts. Furthermore, the Museum had many different interactive exercises to get a closer glimpse of the inner workings of different devices where you could choose a location for a wind turbine and see whether it would be able to generate enough electricity for everyday use.

More importantly, the exhibit put our everyday lives in context by showing which sources of energy produce the most household electricity, which is about 920 kWh. Also, wind turbines can bring electricity to a single dwelling or be connected to a distribution system such as the ones on the wind farms. Overall, the different information offered by the Museum was very encouraging because it showed that we have many different options to satisfy our energy needs in the future.

 

 

 

 

 

Resources:

 

http://energy.gov/eere/wind/how-does-wind-turbine-work

 

Solar Energy

Researchers are always looking for new methods to raise the quality and efficiency of solar cell energy while keeping the cost low. This means finding ways to use as much sunlight as possible that can be turned into electricity. One of the new ways that could lead to solar efficiency is the use of light-sensitive nanoparticles in solar panels. Scientists discovered that this new material has the ability to function outdoors and could raise energy conversion from sunlight to electricity by eight percent. Another recent material called prevoskites, a class of salt-like minerals, are being used in increasing the efficiency of solar panels. One of perovskite’s biggest advantages is that it is produced from low-temperature liquid solution, as opposed to the energy-intensive, high-heat devices in ordinary solar panels. In addition, different international companies are trying to get involved with the fight against climate change by investing on solar energy. For instance, Apple recently announced that it will partner up with China, world’s largest greenhouse producer, to create novel methods of solar energy for its expanding market.

 

 

Resources:

http://www.altenergy.org/renewables/solar/latest-solar-technology.html

https://www.washingtonpost.com/news/energy-environment/wp/2015/10/21/apple-just-announced-dramatic-new-solar-plans-in-china/

http://e360.yale.edu/feature/will_new_technologies_give_critical_boost_to_solar_power/2832/

 

 

 

Fukushima Daiichi Nuclear Disaster and Japan’s New Energy Strategies

In March 2011, Japan suffered a major earthquake that led to a tsunami that disabled the power supply and cooling reactors at the Fukushima Daiichi nuclear site. This catastrophe created major hazardous environmental and life threatening problems for the area of the nuclear site. It also forced the country to come up with alternative energy solutions because nuclear energy provided one third of the country’s electricity. Also, Japan does not have many natural resources such as coal or gas and has to import them with high costs from other countries. One of these new strategies is wind energy. Being an island nation, Japan seems to be conveniently located in the route of strong wind during the typhoon season. In fact, after the Fukushima disaster, the government approved a massive budget plan for developing and improving wind power energy in Japan. In addition to wind power energy, Japan is investing in other forms of renewable energy such as solar, biomass, small hydro, and geothermal. The government is trying to create incentives by subsiding the renewable energy and conservation industries.

 

 

Resources:

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

http://oilprice.com/Alternative-Energy/Wind-Power/Post-Fukushima-Japan-Turns-To-Wind-As-Solution-For-Energy-Crisis.html

http://japanfocus.org/-Andrew-DeWit/3721/article.html

For one of our classes, we headed off to the Museum of Science to explore different exhibitions and get a better understanding of contemporary science. As a group, we explored a variety of scientific displays such as catching the wind, energy innovations, mechanical energy, and renewable and nonrenewable energy. While all of the exhibits were fascinating, one particular one stood out to me.

The tradeoff exhibit was an interesting one because it explained where our main source of everyday energy comes from. It demonstrated how there are seven sources of energy: wind, solar, hydropower, biomass, coal, nuclear power, and natural gas. Personally, I was not familiar with the specifics of renewable and nonrenewable energy. However, this exhibition gave me a clear understanding of different sources. More importantly, the exhibit put our everyday lives in context by showing which sources of energy produce the most household electricity, which is about 920 kWh. Overall, the different information offered by the Museum was very encouraging because it showed that we have many different options to satisfy our energy needs in the future.