2009 Bay Area Science Fair Awards
Congratulations to Carly Christensen, Jenna Fiorello and Benjamin Levy!
Each year the Pacific Energy Center Staff looks forward to visiting the San Francisco Bay Area Science Fair to view all the student entries and select a few that represent creative work and whose subject matter relates to energy and energy conservation. We congratulate our 2009 Winners. They will be honored at an Awards Dinner at the PEC in May, 2009.
Carly Christensen -- Chill Out: Which Insulator Works Best?
In my project, I wanted to see what materials are the best insulators. I tested wood, housing insulation, down feathers, shredded jeans, plastic, crunched paper, and gravel. I will use equal amounts and put one type of insulation into six different plastic bags. I will leave the seventh bag empty to serve as a control. Then I will heat water to 37 degrees Celsius and fill the seven jars with equal amounts of water. I will put one jar of heated water in each insulation bad and record their temperatures once every fifteen minutes for two hours. At the end of the two hours I will compare the temperatures relative to each other and the control.
After the experiment I found that housing insulation did the best at an average ending temperature of 28.1 degrees Celsius, and the worst, besides the control (13.6 degrees Celsius) was gravel at an average ending temperature of 13.43 degrees Celsius. It seems to me that the lighter, fluffier materials with numerous small pockets of air were the most effective insulators. In my research I found that air was one of the best insulators, so I believe this is why my results came out the way they did.
Jenna Fiorello -- Saving Energy One Kernel at a Time
Living in the 21st Century, I’ve been more aware of the energy my family consumes every day. After thinking about our lifestyle, I decided to compare our two microwave ovens and their energy-efficiency. I wondered if our small microwave was more energy-efficient than our larger one. I hypothesized that if the large microwave can cook faster, then it probably uses less energy than the small one cooking the same thing.
To test this, I monitored the watts (the amount of energy at any given moment) that were emitted from our house by viewing our electric meter. I recorded the watts released when the large 1110-watt microwave was on HIGH to the smaller, 700 watt microwave on HIGH. As they were running, I used popping corn in order to control how long each microwave spent time turned on.
According to my calculations, I proved my hypothesis incorrect. The 700-watt microwave actually used 0.009 less kilowatt-hours to cook the same bag of popcorn. That’s around the same amount of energy used to power two 45-watt light bulbs for six minutes! After performing this experiment, I realized that by using our small microwave alone, my family could easily save more money and energy.
Benjamin Levy -- Putting the Squeeze on Energy Harvesting: Piezoelectric Power Scavengers
Technological advances are flooding our world with data networks of wireless computing, monitoring and collection devices, creating a growing demand for clean, efficient, low-cost powering systems. Batteries become impractical when maintenance issues are factored across extensive, remote arrays. Self-sustaining equipment can be developed using energy scavenging technologies, such as y exploiting ordinary human motion that dissipates constantly into our environment. This study considers power that can be harness by capturing and converting ambient mechanical motion into electricity, by means of piezoelectric materials.
Piezoelectric ceramics, such a lead zirconate titanate (PZT), are manufactured to exhibit permanent polarization. Squeezing, pressing or bending the PZT then changes it dipole moment, creating a voltage. For this experiment, piezoelectric disks taken from dismantled buzzers were subjected to compression and tension forces in several configurations, to evaluate which type of strain produced relatively high energy outputs.
The electricity obtained pulsed with extremely variable voltages and currents, and would need to be smoothed and stored via transducer/capacitor circuitry for practical use. However, the data was sufficient to show greater relative piezoelectric efficiency with bending deformation than with direct compression, which could aid in designing mechanical energy harvesting elements, such as PZT-equipped flooring in busy public spaces.