Monthly Archives: March 2014

Museum of Science

Intro

Hello classmates, I would like to begin my blog by thanking Professor Sonek for taking class time to allow us to visit the museum of science.  Although I was raised in Boston, I had not been to the museum of science since childhood.  It was a great time and extremely interesting.  My blog will continue to follow the following outline.  I will begin by describing what I learned and my overall experience in the following four exhibits: Catching the Wind, Conserve @ Home, Energized and Innovation engineers.  I will then finish by stating my opinion on the overall museum field trip.

Catching the wind

 The exhibit explained how turbines transform wind into green energy.  It was extremely interesting to track energy production in the museums own energy lab.  In the picture below you can see the turbines on the roof of the museum.  The exhibit actually allowed us to track the museums wind energy production.

Interactive games allowed me to learn about the decision making involved in deciding where to place a turbine, and what type of turbine should we use.  The exhibit also provided great explanations on how electricity is generated.  The game “Wind Power Challenge”, allowed me to visualize and decide how I would power my community, business, or home.

Conserve @ Home

 “You can make a difference!” That quote summarizes what the exhibit was actually about.  The entire exhibit was a display that expressed how everyone could save energy and make a difference in the environment.

The exhibit presents data on how we can save money while saving our natural resources.  It gave us examples on how to make the greatest savings in our households.  The “What’s a Watt?” display was interesting because it showed which appliances use more energy than others.

One of the images displayed in the exhibit really stood out in my opinion.  It stated “Reduce Reuse Recycle”.

Each one had a meaning:

Reduce the amount of waste you generate

Reuse materials by finding another use for them

Recycle all you can from what is left

The three RRR’s are a hierarchy that describes how we can go about decreasing the overall waste.

Energized

Energized is an exhibit that concentrates on sunlight, wind, water in motion, and other forms of energy.  The exhibit was filled with videos and hand-on activities.  The exhibit displayed rooftop-like solar panels that displayed how a solar panel could power a house.

The introduction or beginning of the exhibit was extremely interesting; it began by defining what role energy plays in our everyday activities.  It then continued by describing what we currently depend on for energy.  Resources such as oil, gas, and coal resource that eventually will run out.  The exhibit then continues by explaining the necessity of developing alternative forms of energy

“Renewable energy is an important part of balancing our needs for energy and a clean environment.  There is energy all around us – in the motion of the wind and water, in the light and heat of the sun, and in heat underground.  New technologies are making these energy sources more useable”.

Innovative Engineers

“Innovative Engineers” was my favorite exhibit out of the 4 exhibits required to visit by Professor Sonek.  The exhibit not only displayed amaizing products created by engineers, but it also added emotion and personal goals to the display.  We had the opportunity to read quotes that displayed what engineers are thinking, what drives them to continue and develop new products.

The display showed products designed by engineers and the purpose of the product.

For example, a product that I found to be fascinating was a robot designed by iRobot that was used by our soldiers to “detect, and dispose of bombs, perform reconnaissance, and carry out high risk tasks that people might otherwise have to do”.

This robot is essentially saving human lives.  Imagine the satisfaction an engineer receives in knowing his invention has saved the lives of American soldiers.

Conclusion

Overall I enjoy the fieldtrip, I spent a significant amount of time enjoying the exhibits.  It was great to tie in our learning’s in class with the works of engineers and scientist who are really trying to overcome modern day challenges.

FUKUSHIMA DISASTER

On March 11, 2011, both an earthquake and a tsunami struck Japan.  The combination of both natural disasters caused an additional tragic event.  The natural disasters knocked out the backup power systems that were essential to keep the nuclear reactors cool.  The image posted below depicts how a nuclear reactor works.

Because the reactors were not kept cool, it caused three of the reactors to undergo “fuel melting, hydrogen explosions, and radioactive releases”.  The unfortunate event led to an evacuation of residents whose world was flipped upside down.  Not only did Japanese families, lose their homes, they lost loved ones, and on top of that they were being evacuated and not allowed the search for the diseased or missing bodies of their loved ones.  The heart-brake of survivors, must have been unbearable, one cannot even imagine the thoughts and emotions undergone by those affected.

In total the Fukushima plant forced the evacuation of 100,000 resident and affected communities up to 25 miles away.  The image below is a great visual example of the areas affected as well as an idea of the population affected.

The red, yellow and green areas on the map are an indication of the level of Caesium found in the area.  Or in other words the level/type of contamination found.

A total of four reactors were written off due to damage in the accident.  Thus far there has been no deaths or cases of radiation sickness.  But the entire disaster is estimated to have been the cause of at least 1,000 deaths.  I’m publishing the quotation stated below simply because I found it fascinating, that as humans we have an actual way of scaling the severity and seriousness of disasters.

“Japan’s Nuclear & Industrial Safety Agency originally declared the Fukushima Daiichi 1-3 accident as Level 5 on the International Nuclear Events Scale (INES) – an accident with wider consequences, the same level as Three Mile Island in 1979. The sequence of events relating to the fuel pond at unit 4 was rated INES Level 3 – a serious incident. However, a month after the tsunami the NSC raised the rating to 7 for units 1-3 together, ‘a major accident’, saying that a re-evaluation of early radioactive releases suggested that some 630 PBq of I-131 equivalent had been discharged, mostly in the first week. This then matched the criterion for level 7. In early June NISA increased its estimate of releases to 770 PBq, from about half that, though in August the NSC lowered this estimate to 570 PBqFor Fukushima Daini, NISA declared INES Level 3 for units 1, 2, 4 – each a serious incident”.

 To summarize the quotation, the NISA declared the Fukushima incident to be a serious incident.

Both of the images below demonstrate how the levels of radiation have dwindled over the period of time since the incident.  But it also lays out how serious, and what a vast amount of area one nuclear power plant damaged.

A serious aftermath regarding the matter had to due with the contamination of the water, specifically the amount irresponsibly released by Tepco.  Although the water was “Slightly contaminated”, the Japanese government and Tepco, were strongly criticized for allowing such actions to take place.  The need for filtering led to a teamwork effort to help decontaminate the water used to cool down the reactor, and the water, which was already in the plant.

“Tepco built a new wastewater treatment facility to treat contaminated water. The company used both US proprietary adsorbtion and French conventional technologies in the new 1200 m³/day treatment plant. A supplementary and simpler SARRY plant to remove caesium using Japanese technology and made by Toshiba and Shaw Group was installed and commissioned in August 2011. These plants reduce caesium from about 55 MBq/L to 5.5 kBq/L – about ten times better than designed. Desalination is necessary on account of the seawater earlier used for cooling, and the 1200 m³/day desalination plant produces 480 m³ of clean water while 720 m³ goes to storage. By mid-March 2012, over 250,000 m³ of water had been treated”.

The link below is an absolutely amazing documentary, please take 45 minutes out of your day and watch it.  There is so much information to learn from the documentary.

https://www.youtube.com/watch?v=fyIBlygNlcc

The video gives you a great perspective of the intensity of the disaster, both from a scientific point of view but also from a human’s perspective.  I gathered a majority of my information from this video.

References:

http://www.fas.org/sgp/crs/nuke/R41694.pdf

http://www.pnas.org/content/108/49/19530.abstract

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

This blog will contain information regarding geothermal energy, how it can be applied for generating heat and electricity, and Iceland’s use of geothermal energy.

What is geothermal energy?  Geothermal energy is Heat from the earth that can be used as an energy source in many ways, from large and complex power stations to small and relatively simple pumping systems. This heat energy, known as geothermal energy, can be found almost anywhere—as far away as remote deep wells in Indonesia and as close as the dirt in our backyards.  Many regions/countries in the world are already beginning to use geothermal energy as an affordable solution to reduce their dependency in fossil fuels.

The image above is a beautiful example of the energy provided by geothermal energy, the natural boiling water in Iceland is a sight to be seen.

Interesting Fact:

“More than 8,900 megawatts (MW) of large, utility-scale geothermal capacity in 24 countries now produce enough electricity to meet the annual needs of nearly 12 million typical U.S. households (GEA 2008a). Geothermal plants produce 25 percent or more of electricity in the Philippines, Iceland, and El Salvador”.

Luckily, the United States has more geothermal capacity than any other country in the world.  Geothermal energy comes from a layer of hot and molten rock called magma below the Earth’s crust.  “The amount of heat within 10,000 meters (about 33,000 feet) of Earth’s surface contains 50,000 times more energy than all the oil and natural gas resources in the world”.

Above is also a very informative link to a YouTube video of a geothermal homeowner who does a great job explaining the process.

http://www.youtube.com/watch?v=kjpp2MQffnw

This link gives a better perspective of how an actual geothermal plant works.

Know lets get more into depth on how Iceland in specific is using geothermal energy.  There are five major geothermal plants that currently exist in Iceland; in In total the plants produce approximately 26.2% of the nations energy.  The geothermal heat is mostly used to heat fresh water which, when hot, can be utilized directly for central heating. 89% of all the houses in Iceland are heated this way.  But the geothermal water is also used in many other ways. It is used in swimming pools, for soil warming, fish farming, drying of timber and wool, animal husbandry etc.

Current researchers from the Iceland Deep Drilling Project are using magma to generate high-pressure steam at temperatures over 450 degrees Celsius, beating the world record for hottest geothermal heat. According to the measured output, the magma generated about 36 megawatts of electricity.  Iceland is without a doubt a front-runner regarding geothermal energy.

The image below will help you visualize the great depths involved in taping into geothermal resources.

“Iceland is named the land of fire and ice for a good reason. It is certainly icy: temperatures hover around 10-20°F (-12 to -6°C) in the winter. But underneath that frozen earth lies fiery hot rock and water — so much of it that 87 percent of the country’s heat and hot water demand is met with geothermal energy and 25 percent of its electricity demand is supplied by geothermal power. Hydropower supplies the other 75 percent of electricity demand, which means that the country is powered 100 percent with renewables”.

With such a surplus in renewable energy Iceland is under pressure to export some of its energy.  Iceland in general prefers to sustain its energy “in house”, with the hope that the energy their land provides them will help future generations in Iceland.

“But the country is weighing a difficult choice right now as it considers what to do with that abundant geothermal energy it is so lucky to have. In 2010, there was a countrywide backlash when Canadian company Magma Energy of Icelandic geothermal energy company HS Orka. Icelanders were uncomfortable with an outsider owning one of its companies. Alterra sold back 25 percent of HS Orka to a consortium of 14 Icelandic pension funds in May 2011”.

Icelanders are in a very interesting predicament, will they keep their energy to themselves or will they continue and allow foreign companies to tap into their resources?

“ High-profile Icelandic blogger Lára Hanna Einarsdóttir says that everyone in Iceland “will pay” if the electricity is exported.  Instead she wants to keep the resource within the country’s borders for future generations.  On the flip side is, of course, money.  Geothermal power is cheap in Iceland and the country could get a nice price for it, if it could sell the power to nations that need clean energy to meet their goals”.

Personally I believe Iceland will fail into temptation, eventually the money will overwhelm the sustainable aspect of holding off for “future generations” and accept the offers.

What do you guys think Iceland will do in the near future? Will they accept the cash or hold off for future generations?

The image below is a beautiful example of geothermal power plants.

References:

http://www.renewableenergyworld.com/rea/blog/post/2013/03/geothermal-energy-in-iceland-too-much-of-a-good-thing

http://www.ucsusa.org/clean_energy/our-energy-choices/renewable-energy/how-geothermal-energy-works.html

http://environment.nationalgeographic.com/environment/global-warming/geothermal-profile/http://iceland.ednet.ns.ca/schedule.htm

http://interestingenergyfacts.blogspot.com/2008/03/geothermal-energy-facts.html

STIRLING HEAT ENGINE & PELTIER DEVICE

Hello class, I am actually looking forward to learning about the Stirling heat engine and the peltier device.  I blog will be outlined in the following manner, first I will describe what a stirling heat engine is and what purpose it serves.  I will continue by doing the same for the peltier device.  I will then conclude my blog by stating interesting facts or links that will benefit you.

The diagram above is a stirling heat engine.

Invented by Robert Stirling in 1816, the Stirling engine does not allow gasses used to leave the engine.  Unlike gasoline or diesel engines, no combustion takes place inside the cylinders of the engine.  Stirling engines are very quiet because of the Stirling cycle.

My curiosity led me to learn more about the Stirling cylinder and how it works.  The key principle of a Stirling engine is that a fixed amount of gas is sealed inside the engine.

There are several properties of gasses that are critical to the operation of Stirling engines:

If you have a fixed amount of gas in a fixed volume of space and you raise the temperature of that gas, the pressure will increase.

If you have a fixed amount of gas and you compress it (decrease the volume of its space), the temperature of that gas will increase.

Let’s go through each part of the Stirling cycle while looking at a simplified Stirling engine. Our simplified engine uses two cylinders. One cylinder is heated by an external heat source (such as fire), and the other is cooled by an external cooling source (such as ice). The gas chambers of the two cylinders are connected, and the pistons are connected to each other mechanically by a linkage that determines how they will move in relation to one another.

The diagram above is a picture illustrating a Stirling cycle.

http://www.youtube.com/watch?v=NvKbPEuMRy4

The link above provides a video explaining how a Stirling engine works.

There are four parts to the Stirling cycle.

1. Heat is added to the gas inside the heated cylinder (left), causing pressure to build. This forces the piston to move down. This is the part of the Stirling cycle that does the work.
2. The left piston moves up while the right piston moves down. This pushes the hot gas into the cooled cylinder, which quickly cools the gas to the temperature of the cooling source, lowering its pressure. This makes it easier to compress the gas in the next part of the cycle.
3. The piston in the cooled cylinder (right) starts to compress the gas. Heat generated by this compression is removed by the cooling source.
4. The right piston moves up while the left piston moves down. This forces the gas into the heated cylinder, where it quickly heats up, building pressure, at which point the cycle repeats.

Now that you have a clear understanding of a Stirling engine let’s move on to explaining a peltier device.

Peltier Device – cooler, heater, or thermoelectric heat pump is a solid-state active heat pump, which transfers heat from one side of the device to the other, with consumption of electrical energy, depending on the direction of the current.

http://www.youtube.com/watch?v=Ipt8xqKbCSw

Please take a look at the link provided above to view how to make a peltier device on your own.

A phenomenon first discovered in the early 19th century. The Peltier effect occurs whenever electrical current flows through two dissimilar conductors. Depending on the direction of current flow, the junction of the two conductors will either absorb or release heat.

Peltier devices are literally heat pumps, which have two sides a hot side, and a cold side. When a voltage is applied (around 12V), heat is ‘magically’ pumped from the cold side to the hot side through the semiconductor junction.

Peltier devices have different power ratings, corresponding to how fast the cold side is able to cool down an object. Another factor is generally specified, the delta-T, which is the maximum thermal difference in temperature between both sides.

Lets now conclude the blog with purposes for each device.  The Stirling engine can be used in each of the following devices:

1. Automotive engines – although unlikely, recently scientist have found a way to mitigate all the difficulties and implement the engine in autos (patent 7,387,093)
2. Electric Vehicles – Stirling engines are part of hybrid vehicles
3. Pump engines
4. Solar power generation

Peltier devices are used for heating, cooling or generating electricity.  They are flexible in that they can be used to do things such as but not limited too, charging batteries, running small electrical devices such as led’s, as well as heating and cooling. Your imagination and the number of peltier elements are the only limitations you have.

References:

http://auto.howstuffworks.com/stirling-engine.htm

http://www.penguinslab.com/peltier.htm

http://www.dansdata.com/peltprac.htm

http://www.survival-manual.com/electricity/peltier-elements.php