Month: February 2016

 Solar Leaf

Daniel Nocera and his research team at MIT have developed the first “artificial leaf.”  Made from a thin silicon solar cell, the leaf is dropped into water where it separates hydrogen and oxygen molecules that are collected and connected to fuel cells that produce electricity. The leaves can’t collect energy as efficiently as traditional solar PVs, but are incredibly cheap to make.

The leaf could bring electricity cost effectively, especially in developing countries, to households that aren’t connected to energy grids.

 Eliodomestico Solar Still

"New Solar Innovations That Could Change The World." Mosaic. N.p., n.d. Web. 24 Feb. 2016.

"Ingenious Solar Projects Impacting the Developing World." Mashable. N.p., n.d. Web. 24 Feb. 2016

"Concentrated Solar Power." World Bank. N.p., n.d. Web. 24 Feb. 2016.

The goal of solar experiment was to see how lights on different distances and with different colors affects voltage on a solar cell.

For this experiment we have been given the solar cell, which we plagued in to the battery and to the computer, five filters of different colors and a flashlight. By clicking start on the computer, our experiment began and we were supposed to light the solar cell. First five trials were without any filters, but the distances of lighting were changed every time. We used the ruler to measure it. For the next five trials, we used five different colors, but the distance stayed the same.

After every trial the computer implemented calculations of the voltage. All we had to do is to sum the last ten and then we had an actual number for the specific trial.

1.                      

2.                      

When all the trials have been finished, by using excel, we were able to make diagrams based on our results.

1.

2.

That leads us to the conclusion that the bigger the distance, the lower the voltage. Also, colors have an impact on lights intensity, because there is diverse voltage for every color.

Nikola Tesla wanted to create the way to supply power without stringing wires. He almost accomplished his goal when his experiment led him to creation of the Tesla coil. It was the first system that could wirelessly transmit electricity. From 1891 to 1898 he experimented with the transmission of electrical energy using a radio frequency resonant transformer of the Tesla coil, which produces high voltage, high frequency alternating currents. With that he was able to transfer power over short distances without connecting wires. However, the Tesla coil does not have much practical application anymore, Tesla’s invention completely transformed the way electricity was comprehended and used. Radios and televisions still use variations of the Tesla coil today.

In 1901 Tesla began his work of a large high-voltage wireless energy transmission station called the Wardenclyffe Tower. Small-scale wireless power transfer as a prototype transmitter for a “World Wireless System” that was to broadcast both information and power worldwide was demonstrated to investors, nut they had pulled out and the facility was never completed. Although Tesla stated his ideas were proven, he had a history of failing to confirm his ideas by experiment, but it seems like he had no evidence that he ever transmitted meaningful power beyond the short-range demonstrations above. In the 110 years since his experiments, efforts using similar equipment have failed to achieve long distance power transmission. The scientists agreed that his World Wireless system would not have worked.

Here is the video that explains the Concept of Wireless Power Transfer:

The transfer of power to a device without wires. Although the wireless transfer of electromagnetic energy in the form of audio, video and data signals is general, the wireless transfer of electrical power is relatively new. Some devices already employ wireless energy transfer without the use of metal contacts. The power is transferred through the plastic cases using magnetic induction. By using magnetic fields, at some point in the future, electric vehicles are expected to be refueled within three feet of the charging station.

“Wireless energy transfer” Encyclopedia of terms. PC Magazine Ziff-Davis. 2014. Retrieved December 15, 2014.

“Wireless Electricity? How the Tesla Coil Works.” Live Science. N.p., n.d. Web. 17 Feb. 2016

“Wireless Energy Transfer.” PC. N.p., n.d. Web. 17 Feb. 2016.

Last Friday we had Generator Lab experiment in our science class. The idea was to observe how Faraday’s law works in real life example. Faraday’s law is about changing magnetic flux in a coil produces electricity.

For this experiment we have been given a generator (magnet that moves back and forth inside a coil of wire), a voltage probe, NXT adaptor and NXT. To make it work we had to shake the generator for thirty seconds and count amount of shakes that we had to write down in Excel sheet. The generator was connected to the computer, which was measuring the voltage for us. Its thirty numbers went to separate column in Excel as well. When all five trials were done we had to count the sum of the squares of the voltages and with our result make a linear curve.

Due to technical problems during the class my partners and me were not able to get those results so here are the results that were given us before the experiment has started:

Here we can observe that with more shakes, the voltage is higher. It proves the Faraday’s law. “The greater is the change in magnetic flux, the greater are the currents and voltages.”

“SpaceX designs, manufactures and launches advanced rockets and spacecraft. The company was founded in 2002 to revolutionize space technology, with the ultimate goal of enabling people to live on other planets.”

Goals:

One of the goals is to improve the cost and reliability of access to space.

In a 2011 interview Elon Musk, one of the formers of SpaceX, said that he hopes to send humans to Mars’ surface within 10–20 years. Musk’s long term vision for the company is the development of technology and resources suitable for human colonization on Mars.

In 2015, SpaceX is developing their own computational fluid dynamics software to improve the simulation capability of evaluating rocket engine combustion design.

Velocity

The reason the astronauts are floating around is that they have no net acceleration. The outward acceleration of circular motion, which wants to sling them out into deep space, exactly balances the inward acceleration of gravity that wants to pull them down to Earth.

Kinetic Energy

In the Falcon 9 rocket, the boost stage is able to accelerate a payload mass of 125 metric tons to 8000 km/h and land on an ocean platform or to 5000 km/h and land back at the launch site.

For a sea platform landing, the Falcon 9 figure of merit is therefore roughly 300 gigajoules (GJ) of kinetic energy and for a return to launch site landing, the number is about 120 GJ.

When trying to understand the value of a reusable rocket booster, the kinetic energy transfer at a 100 km reference altitude is what matters. That altitude is the equivalent of the starting line of a race. The race itself is the kinetic energy.

SpaceX Reusability Progress to Date

SpaceX done several take-off and landing flights with the Falcon 9. These were important to ensure that the final velocity attenuation algorithms worked properly. In particular, it was needed to prove out a hard slew maneuver and a high acceleration landing. The first is important because the rocket is still moving sideways before landing, so it’s necessary to zero out lateral velocity, and the second because landing slowly takes a lot more propellant than landing fast.

TECHNICAL OVERVIEW OF FALCON 9:

HEIGHT                       MASS                                        PAYLOAD TO LEO

70m229.6 ft          541,300kg1,194,000 lb                13,150kg28,991 lb

TECHNICAL OVERVIEW OF FALCON HEAVY:

HEIGHT           PAYLOAD TO MARS     TOTAL WIDTH

70m229.6 ft     13,200kg29,101 lb          12.2m39.9 ft

MASS

1,394,000kg3,075,000 lb

TECHNICAL OVERVIEW OF DRAGON:

HEIGHT WITH TRUNK              TOTAL LAUNCH PAYLOAD MASS

7.2m23.6 ft                                                  6,000kg13,228 lbs

Works Cited:

Nasa. “SpaceX.” SpaceX CRS-6 Mission Press Kit: n. pag. Print.

“About SpaceX.” SpaceX. N.p., n.d. Web. 10 Feb. 2016

“SpaceX.” National Aeronautics and Space Administration. N.p., n.d. Web. 10 Feb. 2016.

The goal of this experiment was to learn about Newton’s Second Law of motion. “ The relationship between an object’s mass m, its acceleration a, and the applied force F is F = ma. Acceleration and force are vectors (as indicated by their symbols being displayed in slant bold font); in this law the direction of the force vector is the same as the direction of the acceleration vector.”

For the experiment we have been given a pulley and the weights. First of all for the controls section me and my partner had to measure the height of the pulley with in our case was 0.24m. The mass of one weight equaled 0.02 kg and we had 9 of them. It means that the total was 0.18kg. We set the power 75 and started our experiment.

For the first set of our experiment we kept the power the same, but kept changing the mass every time. Mass= 0.02, 0.06, 0.1, 0.14, 0.18kg.

The second set was with the same mass, but with different powers. Power=60,50,40,30,20.

From that we were able to get number of acceleration and when we had that we could easily find potential energy.

  W=(mg)h

Potential Enegry=Mass*Acceleration*Height

On the first diagram we can see the force (Mass*Acceleration). With the bigger mass, acceleration is less.

 On the second diagram Force*Acceleration. With the bigger force, acceleration is bigger as well.

The experiment can be counted as successfull because it proves Newton’s Second Law.

During the class, we had an experiment with Lego robot. Each of us had a partner we worked together with. The experiment was about checking the results of how robot is working with its different settings. We had to plug in battery to the robot itself, and then that battery was plugged into two powers on the top of the robot. First of all, we had to measure the radius of the robot’s wheels, which in our case was 2,5 cm. That means that circumference= 0.0628. Then, we got a chance to play with settings.

Time: 1 sec                                      Power 1: 75                                 Power 2: 75

That let us to the next results:

Rotation= 564

# of wheel turns= 1.56667

Distance= 0.09843

Velocity= 0.09843

We made a few trials with different powers and wrote down distance that was given us by computer and distance that were measured by my partner and me, so later we could count % of error.

Trial #1:                                          1sec, power: 62, 62

d_m                                                                              dc

22 cm                                                    24 cm

% of error= 8.7%

Trial #2:                                          1 sec, power: 70, 70

d_m                                                                              d_c

26 cm                                                  28 cm

% of error= 7.4%

Trial #3:                                          2 sec, power 19, 19

d_m                                                                              dc

10 cm                                                  11.1 cm

% of error= 10.4%              

By these results we can see that the percent of error is pretty high, but still we can observe the work of the robot. The bigger power, the longer distance. In case of different powers, robot will stop moving straight and will move right if the power on left is bigger and it will move left if the right power is bigger. It also can make a circle if the one power is much bigger then the other one.

For decades the grid’s basic structure was pretty much the same. According to the Energy Information Administration, fossil fuel-based power plants—burning coal, oil, or natural gas—create nearly 70 percent of the nation’s power, while nuclear power accounts for about 20 percent. The grid delivers electricity from the power plant to anywhere its needed. It’s what is plugged into light switch or power up of the computer. Current electric grid consists of more than 9,200 electric generating units with more than 1 million megawatts of generating capacity connected to more than 300,000 miles of transmission lines.

The Smart Grid represents an opportunity to move the energy industry into a new era of reliability, availability, and efficiency that will contribute to our economic and environmental health. Advantages of the Smart Grid are:

• More efficient transmission of electricity
• Quicker restoration of electricity after power disturbances
• Reduced operations and management costs for utilities, and ultimately lower power costs for consumers
• Reduced peak demand, which will also help lower electricity rates
• Increased integration of large-scale renewable energy systems
• Better integration of customer-owner power generation systems, including renewable energy systems
• Improved security

However there are disadvantages such as blackouts. That can affect banking, communications, traffic, and security. This is a real threat in the winter, when homeowners can be left without heat. It will also cause the following problems: plant production stopped, perishable food spoiling, traffic lights dark, and credit card transactions rendered inoperable. Such are the effects of even a short regional blackout. A smarter grid will add resiliency to our electric power System and make it better prepared to address emergencies such as severe storms, earthquakes, large solar flares, and terrorist attacks. The new technologies will also help ensure that electricity recovery resumes quickly and strategically after an emergency.

“Modernizing the U.S. Energy Grid.” Council on Foreign Relations. N.p., n.d. Web. 3 Feb. 2016. <http://www.cfr.org/united-states/modernizing-us-energy-grid/p36858>.

“SMART GRID.” Energy.gov. N.p., n.d. Web. 3 Feb. 2016. <http://energy.gov/oe/services/technology-development/smart-grid>.

“What is the Smart Grid?” Smartgrid.gov. N.p., n.d. Web. 3 Feb. 2016. <https://www.smartgrid.gov/the_smart_grid/smart_grid.html>.

“the SMART GRID: an introduction.” Exploring the imperative of revitalizing America’s electric infrastructure.: n. pag. Print.