For Day 4, we will be in Mott 8.
Agenda for the day:
- Rachel Johnson from Cherryland Electric will meet with the class 930-1030am to discuss living off the grid power sources and alternative energy
- Deb Smith from IT will talk with us about off the grid living experience at 1045am
- Discuss wind power techniques and pros/cons
- Discuss solar power techniques and pros/cons
- Discuss controversy over wind power turbines
Alternative energy sources are becoming more popular. Living "off the grid" requires people to be able to sustain a healthy lifestyle without depending on the power companies to provide your electricity. Many people have begun to consider what these alternative energy sources may be, how to use them best, install them, and weigh the pros and cons.
Wind Power
When we think of wind power, we generally think of those large, high tech towers with slowly spinning blades that have sprung up in the past decade on hilltops in many areas of the country. But the fact is, wind is one of the oldest sources of power used by man. Our ancient ancestors used the wind to propel boats, grind grain and pump water.
While all of these applications still exist today, wind power is now primarily used to generate electricity at both the large and the small scale. Our discussion today will focus on large utility scale installations. In all cases, it is the kinetic energy, or movement of the air, that provides the mechanical power to perform the various forms of work.
According to a recent report posted by the DOE’s National Renewable Energy Lab (NREL), renewables can contribute 80% of American electricity by the year 2050. Much of it will be provided by wind power installations of this type.
Wind power has some obvious advantages: it’s clean and renewable and relatively cheap. While these advantages are largely global in nature (e.g. reduced greenhouse gas emissions and fossil fuel depletion), the disadvantages are primarily local (e.g. land use, noise and visual pollution). Of course, the main disadvantage of wind power is that the wind does not blow consistently or steadily.
Other issues have been raised, which have often been misconceptions. For example, one criticism is that windmills kill lots of wild birds. This was true of the early windmills, especially in the case of the wind farm located near Altamont Pass in California. Those turbines spun at high speeds and were located near a major avian thoroughfare. Today’s high efficiency turbines spin at lower speeds and use smooth poles to support the turbine instead of the lattice-style structures used earlier – which actually made nice bird nesting grounds.
Today, even the Audubon Society supports wind power, recognizing that global warming causing a far greater threat to the long term viability of bird populations than the occasional collision of a bird with a tower. The number of annual bird fatalities (around 20,000) is tiny when compared to transmission lines or cats.
Another controversy that has been brewing recently is the idea that windmills can cause global warming. This is another misconception.
Based on a study produced at the State University of NY (SUNY) at Albany, the ground around the turbines can warm up at night. This is due to the mixing, by the turbines, of the cool night air at ground level with the warmer air above. While the effect is real, the concern is not, since this phenomenon does not introduce new heat into the planet’s atmosphere, as the carbon dioxide layer does by trapping heat that would otherwise escape into space. Rather, this small, localized effect is simply mixing heat that is already there, with cooler air below it. If you think of it as a pot of soup on a stove, the sun provides the heat, the greenhouse gases form the lid, and the action of the windmills would be like you stirring the soup, albeit with a very small spoon. Life on Earth, as we know it today, evolved at temperatures that were present before the lid was on.
It is true that this mixing of air could impact local weather in the vicinity of the windmills, but experts believe that this effect can be reduced with enhanced turbine blade designs that minimize mixing and by siting the turbines in areas that are naturally more turbulent.
Here then are the wind power pros and cons.
Pros
In summary, wind power, is not a perfect solution, but it is far better than just about anything else we have available at the moment. I would consider it a good long term transitional energy source over the next fifty to a hundred years.
The other good thing about wind: unlike nuclear power, or tar sands oil, which will each leave a long term toxic legacy, when we are finally done with wind, we can simply take down the towers and allow nature to grow back in.
When we think of wind power, we generally think of those large, high tech towers with slowly spinning blades that have sprung up in the past decade on hilltops in many areas of the country. But the fact is, wind is one of the oldest sources of power used by man. Our ancient ancestors used the wind to propel boats, grind grain and pump water.
While all of these applications still exist today, wind power is now primarily used to generate electricity at both the large and the small scale. Our discussion today will focus on large utility scale installations. In all cases, it is the kinetic energy, or movement of the air, that provides the mechanical power to perform the various forms of work.
According to a recent report posted by the DOE’s National Renewable Energy Lab (NREL), renewables can contribute 80% of American electricity by the year 2050. Much of it will be provided by wind power installations of this type.
Wind power has some obvious advantages: it’s clean and renewable and relatively cheap. While these advantages are largely global in nature (e.g. reduced greenhouse gas emissions and fossil fuel depletion), the disadvantages are primarily local (e.g. land use, noise and visual pollution). Of course, the main disadvantage of wind power is that the wind does not blow consistently or steadily.
Other issues have been raised, which have often been misconceptions. For example, one criticism is that windmills kill lots of wild birds. This was true of the early windmills, especially in the case of the wind farm located near Altamont Pass in California. Those turbines spun at high speeds and were located near a major avian thoroughfare. Today’s high efficiency turbines spin at lower speeds and use smooth poles to support the turbine instead of the lattice-style structures used earlier – which actually made nice bird nesting grounds.
Today, even the Audubon Society supports wind power, recognizing that global warming causing a far greater threat to the long term viability of bird populations than the occasional collision of a bird with a tower. The number of annual bird fatalities (around 20,000) is tiny when compared to transmission lines or cats.
Another controversy that has been brewing recently is the idea that windmills can cause global warming. This is another misconception.
Based on a study produced at the State University of NY (SUNY) at Albany, the ground around the turbines can warm up at night. This is due to the mixing, by the turbines, of the cool night air at ground level with the warmer air above. While the effect is real, the concern is not, since this phenomenon does not introduce new heat into the planet’s atmosphere, as the carbon dioxide layer does by trapping heat that would otherwise escape into space. Rather, this small, localized effect is simply mixing heat that is already there, with cooler air below it. If you think of it as a pot of soup on a stove, the sun provides the heat, the greenhouse gases form the lid, and the action of the windmills would be like you stirring the soup, albeit with a very small spoon. Life on Earth, as we know it today, evolved at temperatures that were present before the lid was on.
It is true that this mixing of air could impact local weather in the vicinity of the windmills, but experts believe that this effect can be reduced with enhanced turbine blade designs that minimize mixing and by siting the turbines in areas that are naturally more turbulent.
Here then are the wind power pros and cons.
Pros
- Clean energy, no fuel to drill, frack, mine, transport or burn
- Renewable and sustainable
- Costs are relatively low and continue to decrease
- Abundant domestic supply (16X current electric demand!)
- The power is essentially free once the infrastructure is paid for.
- Low life cycle carbon footprint. Breakeven in eight months.
- Can be used almost anywhere.
- As mentioned earlier, the wind is inconsistent, unsteady and unpredictable
- Wind power is not cheap and like many energy sources, rely on government subsidies to remain competitive.
- Wind farms are generally located in rural areas that might be otherwise picturesque. They are considered by some people to be an eyesore.
- Some people complain of noise from the turbines.
- Wildlife impact. Not only birds, but bats have experienced fatalities.
- Localized impact on night-time temperatures and weather
In summary, wind power, is not a perfect solution, but it is far better than just about anything else we have available at the moment. I would consider it a good long term transitional energy source over the next fifty to a hundred years.
The other good thing about wind: unlike nuclear power, or tar sands oil, which will each leave a long term toxic legacy, when we are finally done with wind, we can simply take down the towers and allow nature to grow back in.
Solar Energy
The sun has been used for drying clothes and growing food for thousands of years, but only recently has the sun been used for solar power.
Concerns over pollution, environmental degradation, and resource depletion have led to an increasing awareness of the importance of developing solar energy.
Just the tiny fraction of the sun's energy that hits the Earth (around a hundredth of a millionth of a percent) is enough to meet all our power needs many times over.
In fact, every minute, enough energy arrives at the Earth to meet our demands for a whole year - if only we could harness it properly.
HOW IT WORKS The sun provides the Earth with two major forms of energy: heat and light. There are some solar powered systems that utilize heat energy while others transform the light energy into electricity.
There are three ways to harness the sun's energy for use in our homes: solar cells, solar water heating, and solar furnaces.
ADVANTAGES
DISADVANTAGES
The sun has been used for drying clothes and growing food for thousands of years, but only recently has the sun been used for solar power.
Concerns over pollution, environmental degradation, and resource depletion have led to an increasing awareness of the importance of developing solar energy.
Just the tiny fraction of the sun's energy that hits the Earth (around a hundredth of a millionth of a percent) is enough to meet all our power needs many times over.
In fact, every minute, enough energy arrives at the Earth to meet our demands for a whole year - if only we could harness it properly.
HOW IT WORKS The sun provides the Earth with two major forms of energy: heat and light. There are some solar powered systems that utilize heat energy while others transform the light energy into electricity.
There are three ways to harness the sun's energy for use in our homes: solar cells, solar water heating, and solar furnaces.
ADVANTAGES
- Once solar panels are installed, they produce energy without generating waste or pollution. They operate with little maintenance or intervention.
- Solar electric generation is economically competitive where grid connection or fuel transport is difficult, costly or impossible. For example: satellites, island communities, remote locations and ocean vessels.
- Once the initial capital cost of building a solar power plant has been met, operating costs are low when compared to existing power technologies.
- They are applicable for low-power uses such as solar powered garden lights and battery chargers.
- A solar panel saves approximately 0.7 pounds of coal per kWh, or 2 pounds of carbon dioxide per kWh.
DISADVANTAGES
- Solar energy systems do not work at night.
- Solar cells are currently costly and require a large initial capital investment.
- For larger applications, many photovoltaic cells are needed, corresponding to high investment costs and large land requirements.
- The cost effectiveness of a solar energy system is dependent upon the location and climate.
Here's resources for students (from Deb):
1. Humanure Project Online: http://humanurehandbook.com/
* Free book download by chapter.
* Free instructions on how to build a composting toilet.
* Free instructions on how to compost.
* Manuals, books, videos, message board.
2. Joe Jenkins on Youtube: https://www.youtube.com/user/jcjenkins01
3. "Poop in a Bucket" song: https://www.youtube.com/watch?v=uGsmKY_RrmI
1. Humanure Project Online: http://humanurehandbook.com/
* Free book download by chapter.
* Free instructions on how to build a composting toilet.
* Free instructions on how to compost.
* Manuals, books, videos, message board.
2. Joe Jenkins on Youtube: https://www.youtube.com/user/jcjenkins01
3. "Poop in a Bucket" song: https://www.youtube.com/watch?v=uGsmKY_RrmI
