Good Day Sunshine: Oregon Country Fair’s Solar Pinwheel

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The hippies ambled into the enormous grove during a hot and muggy July.

They passed through the crowd disguised as singing daises and honeybees, or squeaking orca whales on stilts. They dressed as caterpillars and blew bubbles. Some recited original poetry; others played a violin with an invisible bow. They played accordion, juggled clubs, and put on puppet shows about anarchy.

The rich and endlessly entertaining human-tapestry that hangs out in Veneta, Ore. every year is pretty run-of-the-mill for regular attendees of the idiosyncratic craft festival known as the Oregon Country Fair.

Some visitors wandered into the educational area Energy Park, where guests are regaled with the virtues of alternative energy, recycling, composting, and organic agriculture.

Since summer of 2011, students and faculty from the University of Oregon physics department have hosted a booth in Energy Park where they show off simple machines that demonstrate the principles of clean and renewable energy.

The UO physics booth is sandwiched between companies selling solar heating and power systems. Everything in Energy Park is free – the point is education rather than turning a profit.

The booth workers showed how to produce electricity from sources like the sun, or by employing gravity or taking advantage of differences in temperature, all of which could generate the power to light a room or run a fan.

“These demonstrations have reframed our discussion,” says physics graduate student Andrea Yocom. “We now have the opportunity to discuss how our energy demands are actually produced, and about many different ideas about alternative ways. Plus, since all of our demonstrations are hands-on, we are lucky to witness many exciting moments of discovery.”

Yocom has helped with the booth since its beginning. This year, she entertained and educated fairgoers with other UO physics professors.

“I’m particularly interested in renewable sources taking advantage of what’s available,” says UO Physics Professor Jim Remington. “Often it’s more expensive to do that than burn oil or wood or something, but that’s the way of the future, and I think that the only way we’re going to survive as a species is to adapt to more expensive forms of energy.”

Stan Micklavzina, also a UO physics professor, is host and creator of Mr. Stan’s Science Circus, a traveling exhibition designed to fascinate children and adults with the “antics of the physical universe.”

Micklavzina has noticed a dichotomy between his audience at the Country Fair versus those at the Eugene Public Library or a high school campus: “It’s a very relaxed environment [conducive] to that kind of conversation,” he says. “My gut feeling would be that people who go to the country fair are a more open audience and more inquisitive.”

The booth is especially attractive to children, some of whom are known to work with the hand-cranked generators for hours on end. “It’s just physics principles and science principles,” says Micklavzina. “And the kids can play with that and they’re getting psyched up with science.”

Seeing young children delighted with the booth’s devices encourages Remington.

“That is just positive reinforcement for the basic idea that we need to reduce our expectations of our energy use and think more long-term,” he says.

The Bicycle Wheel Gyroscope

Upon wandering over to the booth, the first spectacle a fairgoer would find is someone standing on a free-rotating platform, holding a bike wheel. This is the bicycle wheel gyroscope, which demonstrates angular momentum and the law of conservation of energy. Rotate the spinning bike wheel in your hand, and you’ll begin to turn around on the lazy Susan beneath your feet.

This law states that an amount of energy within a system remains constant, although it can be transferred from one object to another. Conservation of energy makes concepts like perpetual motion machines – a theoretical mechanism that would run indefinitely without any attention or energy source – impossible.

“We always get people that come up to us with ideas about how you can get a motor that generates energy and gives you free energy, and that’s impossible,” says Remington.

One of the earliest ideas of perpetual motion, which Remington says dates back to ancient Greece, is demonstrated through a waterfall-powered water wheel. A water wheel at the base of a waterfall could pump water back up to the top, which could hypothetically supply the machine with eternal energy. However, friction and loss of energy prevents this.

“Conservation of energy says that’s absolutely impossible, so we can very confidently say, we’re sorry, but there’s a trickster in your life somewhere that’s misleading you,” Remington says.

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The melting ice motor is one of the demonstrations presented at the UO physics booth in Energy Park at the Oregon Country Fair. Power is generated from the transference of temperature from the melting ice cube that sits on a metal platform.

 

The Solar Pinwheel 

The solar pinwheel – a toy that is self-powered by a solar cell placed on the back of a tongue depressor – has pink blades that twirl independently, without help from a breeze when the sun is shining. Solar material and solar-electric material capture sunlight and force electrons to flow in a single direction through a one-way barrier.

“The basic idea is very simple,” says Remington. “It’s just like a battery, but it takes light instead of chemical energy. Both of them cause electricity to move through a circuit to make a motor spin or make a cell phone run.

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The solar pinwheel is powered by a solar cell on the back that generates energy to turn the blades.

The Melting Ice Motor

On a metal platform, a melting ice cube powers a small fan.  Remington says in the 1800s, it was discovered that electricity would flow if any two dissimilar metals were heated on one end and cooled on the other.

Modern thermoelectric materials are more efficient and can cause electricity to flow based on temperature difference. The transference of temperature from hot to cold causes electrons to move away from the atom and down the barrier; this generates useful power.

The Future of Clean Energy

Yocom says it is her responsibility as a physicist to show people the benefits of energy that doesn’t destabilize our habitat or sabotage the environment.

“Part of that mission is finding creative ways to produce electricity without burning fossil fuels, or to produce electricity from ‘waste’ energy like heat,” she says. “Another part of it is about making sure that people are aware of what energy is, how electricity is produced, and what their relationship to that process is. Our relationship to electricity in our daily lives is usually a little one-sided. Most people plug things in, and pay the electric company.”

We have known that free energy from the Sun can be harnessed and converted into usable forms of power for more than a century, such as when Augustin Mouchot demonstrated this in Paris, 1878, by converting energy from sunlight into mechanical motion, or when Frank Shuman built solar energy arrays in the Egyptian desert in 1913.

However, when people realized that abundant oil was cheaper (and more lucrative) than solar energy, it was deprioritized, and we live today with a universal dependency upon fossil fuels like coal, oil, and natural gas.

Although the earth naturally emits carbon dioxide (CO2), it also absorbs the CO2 in the forests and oceans in a practical balance. Humans have released too much CO2 into the atmosphere and oceans as a byproduct of fossil fuel combustion.

The unprecedented rise in CO2 levels in the atmosphere directly corresponds with the start of the Industrial Revolution in 1750. The Earth is unable to absorb the surfeit of CO2 as fast as our civilization produces it.

So the atmosphere traps heat, which can cause dramatic swings in weather patterns, with effects that range from heat waves and rising sea levels to the three-year record drought affecting Californians today.

The strongest force accelerating climate change is the burning of fossil fuels to power our cars and heat our homes. What will it take to bring human independence from fossil fuel combustion and a greater focus on passive energy?

“I think it really involves changing the attitudes of a very large number of people who like the convenience of driving a car everywhere, of taking advantage of clean energy and really ignoring the future consequences of that,” says Professor Remington. “And that’s a pretty deeply ingrained attitude in our society – that we have the right to do whatever we want, and we can do whatever we want to the environment.”

Micklavzina believes that the general public will switch to a new, environmentally friendly form of energy when it becomes economically feasible.

“Everything relies so heavily on the economy that the economy is going to dictate whatever,” he says. “No matter what people keep proving, the economy is going to keep proving which ways things go [because] we’re a capitalist country. … I’m still driving, because damn, it’s convenient.”

Professor Remington points out that we’re failing to exploit a clear and sustainable energy source that could power our modern lives: the sun. Almost all life on Earth, from the plants to humans, is solar-powered. The Sun provides the Earth with a massive and virtually boundless supply of energy. Remington says on an ordinary sunny day, the Sun provides an average of 1000 watts of solar energy for every square yard of the Earth’s surface.

“It’s an absolutely enormous amount of energy,” he says. “[However] it seems to be more expensive to tap that than it is to burn oil or natural gas, so it hasn’t been practical.”

Physics professor Greg Bothun confirmed this; the Earth receives more solar energy in one hour than our civilization uses in a year.¹

Convincing others to reduce demand or switch to different forms of energy is an uphill battle; this involves re-configuring an instinctive and well-established routine for most humans.

Clean alternatives are available, even though they may be relatively expensive. Photovoltaic valves, which generate electricity from sunlight, have become much more efficient and much cheaper to make, and they can last roughly 20 to 30 years.

Remington says a solar panel installed at home will not only pay for itself in a few years, but will produce useful energy for the rest of the life of the house.

“That should just be standard operating practices, and I don’t know why it isn’t,” he says.

Remington has installed photovoltaic panels at his home. When the sun is shining, a solarium uses passive solar energy to heat the water in the house. The initial investment for solar installation cost him roughly $2,000, but he has saved on his electric bill ever since. “So I’m saving quite a bit,” he says, “several hundred dollars a year.”

That scientific research into clean and renewable energy should always be endorsed and sponsored is the most dramatic lesson from the booth workers in Energy Park.

“Education for the public is important, stimulating people to want to study science is important,” says Micklavzina. “[We’re] stimulating the public to understand why we do research and who we are and why we keep on pursuing these things and what’s important with it.”

The lessons in physics and science taught at the booth, explained in sensible, jargon-free language, stand out among the rest of Energy Park. The entire fair is not only an exhibition to showcase crafts, skills, and talents, but it’s also an important education in being a good neighbor in the community of Earth. Everyone shares a camaraderie of sorts, being suspended under the same Sun.

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¹Greg Bothun, professor of physics and astronomy, says that the sun’s intrinsic energy is 10^26 watts. On the Earth, we receive 175,000 terawatts (TW), compared to our electrical use of 10 TW.

 

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