Last week in class we conducted an experiment using a solar cell.  Solar energy works by taking direct sunlight and converting it into energy.  Solar cells, which are what was used in this experiment, generate an electric current when struck by sunlight.  The solar cells, also called photovoltaic cells, generate an electric current by collecting particles of sunlight called photons and converting them into electrons of direct current.  These electrons then move into an inverter that converts the direct current into alternating current. (http://www.gosolarcalifornia.ca.gov/solar_basics/how.php)

To start the experiment, we put the solar cell face down so that no light was striking it and recorded the voltage output in Excel.  We then measured the voltage output when our light source was at different lengths to see the relationship between light intensity and voltage output and wavelength of light and voltage output.

 After we recorded our results, we set our light source at 10 cm and placed different colored filters in front of the solar cell.  This was to see if colored filters affected the voltage output.  According to the data collected, the different colored filters didn’t have a major effect on the voltage output of the solar panel.  The colors that seems to affect it the most are gold and blue.

Here are the graphs showing the relationship between distance and voltage and voltage as a function of filter color.

The data results I am showing in this post are not our results.  After we completed the experiment all of our data was lost, so I am showing you someone else’s data from the same experiment.

Last week, Professor Tom Vales gave our class a brief, but very informative, presentation.  Professor Vales began the presentation by telling us about alternating currents.  Alternating current is when charges periodically change directions.  Alternating current is what is used in the Tesla coil, invented by Nikola Tesla.  The Tesla coil increases frequency and voltage.  Professor Vales then gave us a demonstration using the Tesla coil and different kinds of lights.

He first showed us what the spark looked like on its own.  Its hard to see in the photo, but the spark is about seven inches tall.

Next, he showed us what happens when a light comes within close proximity of the spark.  As you can see, the lights light up.  This amazed me because the lights were not attached to anything, they lit up because they were close to the spark.

Professor Vales completed his presentation by showing us how you can make the spark spin in a circular motion. It’s difficult to see in this photo, but that is what is happening here.

Although brief, the presentation was very informative and fun to watch.

Nuclear power has been a controversial topic since its start.  Nuclear power was originally used for the production and manufacturing of weapons, leading many to believe it would have a harmful impact on our society.  Anti-nuclear activists argue that continuing the support for nuclear power will have major negative effects on our health and the environment.  The pro-nuclear documentary Pandora’s Promise, directed by Robert Stone, argues that nuclear power is not what anti-nuclear activists make it out to be.  The documentary starts out by showing anti-nuclear protests and explaining misconceptions about nuclear power.  These protests included songs against nuclear power and chanting things like “No more nukes!”

Misconceptions about nuclear power, such as it causes cancer, give it a bad name.  At the beginning of the film Michael Shellenberger, who is now pro-nuclear, stated he always believed nuclear power was “something sinister” and a “lurking danger”.  Mark Lynas also stated, “I was against nuclear power because I am an environmentalist.”  The film attributes these views to “scare tactics” used to stop the nuclear power industry.  Scare tactics included reports of millions of deaths dues to exposure to radiation, shortened life spans due to exposure to radiation and genetic consequences that will last for many years to come.  After research conducted by respected health organizations, these were proven to be false.  The Chernobyl accident is the perfect example of this. The Chernobyl accident happened when a nuclear reactor, that was later deemed unsafe due to a design flaw and serious mistakes made by workers, exploded.  The explosion killed many workers and sent radiation into the atmosphere. Anti- nuclear activist made claims of millions of deaths and illnesses caused by this accident.  When researched by respected health experts, a direct link between exposure to radiation and deaths could not be found in most cases.  Also, the accident did not result in millions of deaths.

Later in the film, the benefits of nuclear power are discussed. Nuclear power would provide us with a clean, unlimited source of energy.  Nuclear energy produces steam and no carbon dioxide, meaning it is better for the environment.  Coal, which is where most of energy comes from, is the most dangerous out of all the sources of energy.  When coal is burned it releases carbon dioxide along with sulfur dioxide, nitrogen oxides and mercury compounds (epa.gov).  These are harmful to our environment and our health.  The film also states that coal usage has the highest mortality rate and nuclear has one of the lowest.  Some might say waste produced by nuclear power is the most harmful, however, nuclear power produces has significantly lower amount of wastes.  Also, technological advances are ensuring nuclear accidents do not happen in the future.

Emissions associated with fossil fuels are not released by nuclear energy.  Nuclear energy is a clean and safe way to produce energy, which is essential because energy usage is expected to increase dramatically by the end of the century.   Not supporting nuclear energy would be a mistake because, as stated in Pandora’s Promise, being anti-nuclear means being in favor of harmful fossil fuels.  With this dramatic increase in energy usage and an increasingly unstable environment, nuclear energy appears to be the most reasonable option.

In class we conducted an experiment exploring Newton’s 2nd Law, the Law of Conservation of Energy, velocity and acceleration, and power.  To do this we used a Lego Mindstorm Motor to lift weights using a pulley.  First, we kept the power level at 75 and took weights off the pulley to change the mass.  By taking off some of the weights on the pulley, we increased the rate of acceleration.  Then we kept the mass at 0.25kg  and changed the power level. By changing the power levels, we changed the rate of acceleration as well.  The higher the power level the faster the rate of acceleration.  All of our data was automatically recorded in Excel.  Then using Excel, we determined Potential Energy and Power.

After we did that we made graphs representing Power Level vs. Power, Battery Discharge vs. Potential Energy, Mass vs. Acceleration (fixed power level), and Power vs. Acceleration.

Newton’s 2nd Law was tested when we kept the power levels fixed and changed the mass and when we kept the mass fixed and changed the power levels.  The Law of Conservation of Energy was explored when we kept the power level fixed and observed battery drainage.

Demand response is defined as changes in electrical usage by demand side resources from their normal consumption patterns in response to changes in the price of electricity overtime, or to incentive payments designed to induce lower electricity use at times of high wholesale market prices or when system reliability is jeopardized.  In other words, it reduces energy consumption to relieve stress on the power grid through higher rates at certain times of the day and financial incentives.  To do this energy users do simple things, such as, turning off lights, the AC, pumps and nonessential equipment for small amounts of time.  This is not too much to ask for because there are financial incentives, grid stability increases and it is beneficial to the environment.  By using less electricity, you are lowering your monthly cost for electricity, decreasing the risk of blackouts and reducing levels of carbon dioxide.

The electricity used to power consumers’ appliances comes from the power grid.  The power grid must support the base load, or the minimum amount of power estimated for daily use, and usage spikes that occur at certain times of the day.  During these peak times of the day energy use rises, increasing the risk of blackouts, or power supply loss.  Blackout are not only annoying and inconvenient, they are also very costly.  Blackouts cost businesses about $50 billion annually and in 2003, one cost New York City about $750 million.

Demand response will also lower the amount of carbon dioxide levels, which are harmful to our environment.  On average, homes in the United States alone release about 150 million tons of CO2 heating and cooling without demand response.

With an estimated 40% increase in energy demand by the year 2030, demand response is a must.  With demand response technology, peak load problems will be detected and power diversion and reduction in areas of concern will automatically take place.  These smart grids will also shift fuel types to balance fossil fuels and renewable energy.

Websites used:

www.enernoc.com

www.science.howstuffworks.com

www.energy.gov

www.ferc.gov

The Mildred F. Sawyer Library at Suffolk University is a beautiful library located at 73 Tremont Street.  The library is open from 8 am-12 am and can be reached at 617-573-8532 (Reference Desk) or 617-573-8535 (Circulation Desk).  With about 200,000 books and ebooks, at least one copy of all textbooks required for undergraduate and graduate courses at the College of Arts and Sciences and the Sawyer Business School and access to an off-campus database, students will always have the resources needed for academic success.  Students who access the off-campus database on the Sawyer Library website have the opportunity to search for articles and eJournals.  Also on the website, students have the option to ask questions under the “Ask a Librarian” tab.

Aside from the academic resources provided, the library offers students a quiet place to work and study.  The Sawyer Library has thirteen Group Study Rooms located on the third and fourth floors.  Study Rooms must be reserved two weeks in advance.  Students are allowed to reserve one room for one day for up to two hours.  There are also many computers, printers and photocopiers for students and loans laptops for in-library use. Inside you will find many lounge chairs, stations, and vending machines ensuring students’ comfort while working.  Located on the ninth floor is the Library Commons which is a student lounge open from 9 am-7 pm.  If you are looking for the perfect place to  study and do homework, the Mildred F. Sawyer Library is the place to go.