For this blog, I decided to reference the Silicon valley based company, Tesla. Since they have some of the most innovative approaches to this topic, and they’re company is starting to take off.

For all the energy required to propel a vehicle, not all of it makes it to the wheels. Some of it is lost to friction and heat. Vehicle inefficiency can be classified into two categories of losses: road-load and energy conversion. Road-load includes wind resistance, mechanical friction (bearings, hubs, driveshaft, etc.), and tire rolling resistance and affects affects all kinds of vehicles.  As a car speeds up, wind resistance increases. Therefore, road-load is greater at higher speeds and is dependent on the aerodynamics of the vehicle. Road-load can be minimized by designing brakes, bearings and other rotating components with less friction. It is also important to use tires that have low rolling resistance and make the vehicle as light as possible. Energy saved by decreasing road-load can have a significantly positive impact on range.

In an electric vehicle, chemical energy is stored in a battery. Tesla uses Lithium-ion batteries because of high energy density. Converting the chemical energy to free electrons (electrical energy) can be greater than 90% efficient – some energy is lost to heat in cells and other battery pack components such as current conductors and fuses. The remaining components of the Tesla powertrain – the drive inverter and motor – are also extremely efficient. Overall, drive efficiency of the Tesla Roadster is 88% – almost three times more efficient than an internal combustion powered vehicle.

Tesla leverages efficiency and an effective powertrain to create the most efficient sports car on the market today. Other companies should consider Tesla as a model of innovation and sustainability, by focusing on alternative sources of energy. I am curious to see how this company performs in the future and how others will follow.

http://www.teslamotors.com/

The exhibit on renewables had some great insight, and it was mostly about solar panels. We need energy for our everyday lives, and the sources we mainly rely on today are polluting the planet and will eventually run out. Our planet enjoys resources that replenish constanstly, like wind, solar, geothermal heat, and moving water. What I found very interesting was CSP. Concentrated solar power (CSP) focuses sunlight onto a small area and uses the resulting heat to make electricity. Mirrors or lenses concentrate the scattered light from the Sun into a focal point, heating up a fluid by hundreds of degrees. The heat is used to make steam, which moves a turbine and generates electrical power. Sunlight is so abundant, but dispersed, a CSP structure focuses the light using troughs, dishes, towers, and sunlight is used most effectively. These structures can take up a lot of space; however, if you place it in an open desert for example, you can collect a lot of light for a relatively low cost. Since light is intermittent, energy can only be retrieved at certain hours of the day. Some plants utilize molten salt to store heat for hours.

The exhibit on photovoltaics was pretty useful as well, however, it contained a bunch of information I could have found on the internet. I learned about the different ways you can implement solar panels on existing structures like building rooftops, walls, curtains,  or to make new ones like parking structure canopies. Currently, it is still pretty expensive to implement. I am curious to see how companies try to make this a cheaper source of energy, either by using new cheaper  materials or making the panel more efficient.

Tom Vales, a professor at Suffolk University, kindly came in and talked to us about several devices that use different types of energy.

The first example was a Stirling engine, named after Robert Stirling in 1816.

It was invented as a substitute for steam engine. Steam engines were used for running water/mills, however, it wasn’t the best quality or most efficient. The machine would even fracture and blow up! High pressure steam could severely injure people.

The engine is a hot air engine that moves hot and cold air to generate heat. So, it works on differential in temperature and a difference of 4 degrees makes the engine run. It is comprised of a displacer and a power piston and is about 80% efficient. It is used for pumping water and many other applications.

The second example was the Peltier engine. This engine uses two dissimilar metals, bismuth and copper, joined together. Once you apply heat to one side and cold to another, it generates electricity. However this device is not very efficient, it is actually under 40%. The most popular use is for computers, used to cool down internal components.

The next example is a Mendocino motor, named after the place where it was invented Mendocino California. This engine has 4 solar cells and 2 coils of wire. As light hits the solar cell it generates current, which then reacts with field magnet and turns the cell 90 degrees. It keeps turning and starts the process over, keeping the cell in perpetual motion. It floats due to electric levitation.

We also used a piezo igniter, similar to gas grill ignitor. Inside is small piece of quartz crystal with wires attached. The button (igniter) pushes on the face of the crystal. If you squueze it in one direction, the crystal generates voltage on the other side. It is used on radio transmitters. The piezoelectric effect is understood as the linear electromechanical interaction between the mechanical and the electrical state in crystalline materials with no inversion symmetry. Piezoelectricity is found in useful applications such as the production and detection of sound, or generation of high voltages.

We proceeded to talk about Nikola Tesla, which was an inventor, engineer, physicist, and futurist with over 700 patents, but is best known for his contributions to the design of the modern alternating current (AC) electrical supply system. Professor Vales preached about how Tesla was an unsung heroe and much greater than Edison. He could have made millions but only cared about inventing. Vales brought in a Tesla Coil, which was primarily built to conduct wireless energy. At high frequencies, the skin effect is created, which sends signals right over your skin, so you dont even feel it. The coil also turns a light bulb into plasma globe. Early doctors believed it had medicinal powers so it was used on patients for various reasons, however, it did absolutely nothing.

The nuclear disaster was a series of unfortunate events that occured at the Fukushima I Nuclear power plant propelled by the Tohoku earthquake and tsunami in March of 2011. It was the largest nuclear disaster since Chernobyl and the second to measure a level 7 on the International Nuclear Event Scale. Such an event should have been predicted and planned for, although officials found gaps in the plants safety procedures. Even though there was a natural disaster that fueled this unfortunate situation, this event was ruled as a man-made disaster since it could have been prevented.

Chairman Kiyoshi Kurokawa stated, “Its fundamental causes are to be found in the ingrained conventions of Japanese culture: our reflexive obedience; our reluctance to question authority; our devotion to ‘sticking with the program’; our groupism; and our insularity.”

The Tepco Fukushima Nuclear Power Plant accident was the result of collusion between the government, the regulators and Tepco. They effectively betrayed the nation’s right to be safe from nuclear accidents. The main problems were deficiencies in their regulatory and organizational systems and the lack of developing basic safety requirements. This was not caused by the incompetency of any one individual, but rather, the whole organization, “Had there been a higher level of knowledge, training, and equipment inspection related to severe accidents, and had there been specific instructions given to the on-site workers concerning the state of emergency within the necessary time frame, a more effective accident response would have been possible…Sections in the diagrams of the severe accident instruction manual were missing.”

Safety procedures that could have been taken to prevent a disaster in case of an emergency, like the tsunami:

• Protecting emergency power supplies, including diesel generators and batteries, by moving them to higher ground or by placing them in watertight bunkers
• Establishing watertight connections between emergency power supplies and key safety systems
• Enhancing the protection of seawater pumps and/or constructing a backup means to dissipate heat

The total release from the entire Fukushima disaster, in terms of Cesium-137(which along with strontium-90 are the two primary substances preventing Chernobyl being inhabited), is approximately 1.5 × 10¹⁶ becquerels (Bq) of Cesium-137 released.

Becquerel (Bq)

• One disintegration per second of a radioactive material, also defined as “The activity of a quantity of a radioactive material in which one nucleus decays per second.”

The cleanup operation will take decades and may cost hundreds of billions of dollars.

http://www.bbc.co.uk/news/world-asia-18718486

http://carnegieendowment.org/files/fukushima.pdf

The Severity of the Fukushima Daiichi Nuclear Disaster: Comparing Chernobyl and Fukushima

Solyndra’s promise: “Solyndra’s solar power solutions offer strong return on investment and make great business sense. Our cylindrical technology was designed for the rooftop and offers the benefit of light weight, low cost and the fastest, easiest installation of any solar technology. In more than 1000 installations around the world our customers are converting underutilized rooftop space into clean energy from the sun.” Solyndra was a manufacturer of cylindrical panels of copper indium gallium selenide (CIGS) thin-film solar cells. On 1 September 2011, the company ceased all business activity, filed forChapter 11 bankruptcy, and laid off all employees. The company is also being sued by employees who were abruptly laid off. Their efficient and innovative technology looked extremely promising, and a chance to create jobs in America. That was the reason the White House, along with Obama, approved a $535 million dollar loan to back the start-up from Silicon Valley. The FBI is currently investigating what role in political fundraising helped make this scandal possible. Th einitiative was called “Technology for Obama”. The intention was great, create clean, efficient energy and create jobs for thousands of Americans. However, it resulted to be a political effort to satisfy the appetite of politicians, and now Republicans are retaliating, despite the fact that they have been in similar situations. The intention of the investment was great, but government officials need to be more cautious in analyzing a company’s operations as well as the honesty of its employees, especially the board, when making such a large investment in this economy. “The Obama Administration betrayed American taxpayers when it dumped hundreds of millions of public dollars into Solyndra while ignoring clear warnings about the company’s dire financial situation,” Romney campaign spokesman Ryan Williams said in a statement.

References:

http://abcnews.go.com/blogs/politics/2012/07/obama-fundraises-with-players-in-solyndra-scandal/

http://articles.chicagotribune.com/2011-09-18/news/ct-met-kass-0918-20110918_1_solyndra-loan-guarantee-obama-fundraisers-obama-white-house

This week, we attempted the previous experiment again. These are the results we attained:

As you increase the mass, acceleration decreases. 

F=ma, as force increases, acceleration increases

As you increase the power level, the power discharge increases and more power is exerted. 

The smaller the mass, the smaller the battery discharge. This is a function of battery to mass with the same power level.

In this week’s lab, we used a generator to create electricity and store it in the battery. We recorded  The changing currents occuring from the shakes are transferred into power and provides light for the battery. The first trial was with 0 shakes and came to be 0.84. Second trial was 24 shakes which equaled 0.101 and 70 shakes equaled 150.

In this week’s lab we explored Newton’s Laws.

1.      Newton’s 2nd Law i.e.,

2.      The law of conservation of energy

3.      Velocity and acceleration

4.      Power

We used the Lego Mindstorm motor to lift weights with a pulley.

Setting the power level of the motor will set the toque on the motor wheel which will result in a particular force used to lift the masses.  The higher the power level, the greater the force

1.      Explore Newton’s 2nd Law i.e. by

a.       Keeping the power level fixed and changing the mass.  Does the acceleration vary withmass?

We found that by decreasing the mass (kg) while keeping the same power level, the time (s) and battery discharge (mV) decreases. However, the speed (RPM) and acceleration (RPM/s) increase.

b.      Keep the mass fixed and change the power level.  Does the acceleration vary with power level?

We found that decreasing the power level decreases the power level (mV), speed (RPM), and acceleration (RPM/s). However, the time (s) increases.

We measured the distance travelled with a ruler : 30 cm

Results from experiment:

NXT Robotics Lab

The purpose of this lab was to understand how the VI measures the distance the wheels travel, and the speed at which the car travels. We also recorded the distance travelled with a ruler and calculated the percentage of error.

With a ruler measure the diameter of the wheel and compute the circumference of the wheel in meters.

Circumference = p*diameter

= .175

How are the degrees that the wheel rotated related to the number of turns of the wheel?           Each wheel rotation in turns is equal to 360 degrees.

How are seconds related to milliseconds? 1 second equals .0001 milliseconds.

How is the distance related to the number of turns? Distance = circumference * # of wheel turns

We ran three tests with the same time for the wheels to turn. The first test we ran at 75% power level, the second test we ran at 50% power level, and 25% for the third test. The discrepancy can be attributed to the fact that our measurements with the ruler were not exact. In contrast, the computer measurements were much more accurate, and the comparison between these two measurements accounts for the percentage of error.

To calculate % error:

| distance of ruler – distance computer | / Average (distance computer and distance ruler)

Tests 1,2, and 3