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Clean Energy 101: Are solar and wind clean energy?
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This is the third part of the Clean Energy 101 series. This article is focused on whether solar and wind are truly clean energy. Energy costs are projected to continue to increase. Additional information found here: http://www.eia.doe.gov/oiaf/forecasting.html
Do you wonder why renewable resources are not yet widely utilized in our country? Countries like Germany, Sweden, and Italy are embracing these resources to a much greater degree. Yet the U.S. still relies heavily on fossil fuels. You will decide which are the clean energy resources.
Solar Energy:
The United States invented much of the modern solar technology, while the rest of the world (even developing countries) is creating much more power from it than we are. If you care to learn more about what happened to the solar revolution in the U.S., check out this site to learn about the history: http://www.theatlantic.com/doc/200907/carter-obama-energy
Colorado has over 300 days of sunshine a year, so there is a great deal of an untapped resource shining from the sky daily. This resource doesn’t need to be mined and transported daily (although many of the materials that go into the production of solar technology do); nor is it extracted from turbulent countries in the Middle East. Most photo voltaics (solar electric panels) are made primarily from silica, which is not considered hazardous and does not emit GHG (green house gases). However, other ingredients in their manufacture do have hazard levels much as painting vehicles or building furniture with resins and stains do. The big question is whether they become a small part or a large part over the life (over 30 years) of the solar collectors and systems.
In its powder form (silica dust), it is hazardous to breathe over long-term daily exposure without appropriate filtration masks. However, it doesn’t require disposal in a gigantic hole in the desert, (unlike spent nuclear fuel rods), at a high long term financial cost, and terrorists, as far as we know, are not planning to use solar energy to wipe out their enemies. It doesn’t require a massive infrastructure in order to the produce the energy or any high costs to transport it. In addition, P.V. panels can produce energy for over 30 years or more and can be placed right on top of your home or business. It will produce energy without the dangers of contracting cancers from it or even increasing asthma rates in your community. If your home is off grid, you don’t pay any power bills. However, off grid systems require a battery storage unit, so choose wisely on the type of batteries used. You can still find rebates and tax credits for using these solar alternatives and they are likely to increase with the demand of alternative energy sources.
In fact the raw materials are abundant throughout the world and you need only go as far as the beach or look through a glass window to find silica. However, it does take a specific type of silica and process to convert solar radiation into electricity. P.V. requires one of the following: crystalline silicon (x-Si), amorphous silicon (a-Si), copper selenium (CIGS), and cadmium telluride (CdTe). These require a fabrication process, which does not emit radon gases like U238 (most abundant type of uranium used for nuclear power).
Types of Solar:
There are four common types of solar energy collection: Photovoltaic, concentrated solar, solar thermal electric, solar thermal water heaters, and many combinations and variations. Solar energy can be stored easily for about 6 hours in a concentrating solar plant using eutectic salts that change phase to store high temperature thermal energy.
Sunlight is converted into electricity from solar cells made from layers of silica crystals (listed above). Concentrated solar or solar thermal electric (STE) uses either large reflective parabolic dishes (much like a satellite dish) to power Stirling engines or highly reflective troughs to reflect sunlight to a power tower or to a tube containing a high-temperature fluid to create steam to run a generator.
One reason that solar has not been a major energy resource in the U.S. is because fossil fuels are a cheaper resource currently. Remember that fossil fuels are not a renewable resource and will soon be depleted to the point that they are too expensive to mine, drill, and “protect.”
A perceived disadvantage to solar is its collection/conversion efficiency. P.V. currently has an efficiency level of about 30% with triple junction solar cells (more expensive). However R&D (research and development) continues to work to improve efficiency levels.
The most cost effective way to make solar more efficient is by conserving electricity by improving insulation, using energy efficient appliances, cutting down on usage, (including phantom loads), and using energy efficient lighting fixtures and/or systems in buildings. Once the needs of the building are reduced then a smaller array will be required. In order to acquire sufficient energy for remaining energy needs, PV arrays must be placed on or within proximity of homes and businesses. Even with rebates and tax credits, as a general rule, only those with lots of money or those receiving tax subsidies or grant money from the government (low income housing) can afford P.V. There are alternative solutions being developed, like long-term lease arrangements which can make P.V. competitive. Another reason that costs for P.V. are high in the U.S. compared to other countries is because places like Germany have a high demand for this resource. Additionally, their government provides feed-in tariffs to their citizens, unlike the U.S. These feed-in tariff programs offer low interest loans to purchase the panels, which provide power to the building and the grid. The payback is a few years with a high return on the investment.
Plus, there may be promise in thin film technologies in P.V. They are less expensive than x-Si, but require a great deal of space in order to be efficient for homes and businesses. One example is thin film solar electric roof tiles to provide electricity for homes. Most thin film is used in small electrical appliances like calculators, watches, flashlights, etc. While this technology is less efficient, they are also less expensive. They are being used in many developing countries in place of kerosene or wood for lighting at night (See article on the Green Tech MeetUp to learn more). This is a growing industry and there are many companies coming to Colorado to manufacture thin film solar.
Solar proponents would like to see more P.V. manufacturing plants in the U.S., like Evergreen Solar. These plants will provide many more jobs than jobs from coal. However, currently China can make the panels for less because of their unregulated environmental standards (results in lack of clean drinking water) and labor laws. In addition, the governments of China and the U.S. signed a trade agreement during the Clinton administration, which increased Chinese imports and severely cut American exports and manufacturing jobs. The Chinese were not interested in our products and could make electronics, textiles, and more for much less. Will it be the cost of fossil fuels, cheap labor, lack of clean drinking water, or the changes in trade agreements that will affect P.V. panel manufacturers’ location?
Large STE arrays are spreading across the desert southwest and one of the largest in the country is being proposed in the San Luis Valley. The planned facility will produce at least 200-megawatts of power. Many regions of the San Luis Valley are tax revenue poor and believe that the solar project will bring more jobs and revenue to the region. However, like all large scale electrical grid projects, the project may require overhead high transmission wires, which are less expensive than buried lines, to carry the power to Pueblo. The side effects of any electrical grid project are the costs (no matter what energy resource) of transmission lines, which could have possible negative health effects from electromagnetic radiation.
Solar thermal water heaters are used in small scale projects for residences and businesses. Solar thermal is used to heat either water or another liquid to heat buildings or to provide domestic hot water.
While solar may have limitations on its efficiency, it is by far the energy resource that uses fewer resources than many of the other energy sources we now use. Its impact on the environment is far less. Do the benefits of solar far outweigh the costs? Is this clean energy?
Wind
Recently T. Boone Pickens called off the largest wind farm project in the world in Texas, due to technical problems and financing. This may still become a wind farm that would provide 4,000 megawatts of power for 1.3 million homes. Wind is still a strong supplement to the grid. However, much like all large scale electrical grid-tied projects, it too will require high voltage transmission lines traveling long distances. Wind technology works best close to its end use.
Colorado has its share of wind and Xcel uses electricity produced from wind and sells it to customers through the Windsource program as well as using wind in the mix of the other energy resources to all its customers. There are plans by Duke Energy to build a wind farm near Burlington to produce an estimated 51 megawatt plant on approximately 6,000 acres. This electricity will be supplied to Tri-State Generation and is expected to be in operation by the end of 2010. However this is a drop in the bucket in comparison to the state’s thirst for electricity.
There are two common types of wind turbines: Horizontal axis and vertical axis. The large turbines are used specifically for large scale grid power, but some residences and businesses are using smaller turbines to supplement power. The typical grid tied turbines are made of carbon, wood, and fiberglass materials for the blades, a steel tower, and a concrete base. These stand alone towers need to be in areas with few obstacles and receive a consistent wind. The plains are a perfect setting for wind turbines.
Just like many other energy resources, electricity produced by wind often travels long distances to get to its end user (power consumer), which means transmission losses and high costs for transmission lines. However, think about how much coal travels hundreds of miles across Colorado each day (diesel powered trains) to get to the plant, where it’s then turned into electricity and then transmitted over power lines to customers over vast distances. Wind does not produce any GHG or pollution that would poison lakes, forests, water, and the air. While perhaps not quite as constant as the sun’s energy, it is quite abundant on the plains. Turbines do have moving parts that need periodic maintenance and/or replacement. However this fact creates jobs for Americans. That’s exactly what the Danish wind turbine manufacturer Vestas Nacelle has in mind. Right here in Colorado Vestas has a plant in Windsor and plans to open two more manufacturing plants in the following cities: Brighton and Pueblo. Pueblo will be the largest manufacturer of wind turbine towers in the world.
Another big question is whether wind turbines have an impact on the climate and weather patterns. Manmade objects like buildings and asphalt already have a huge impact, at least locally, on temperatures. Cities absorb much more heat than green areas with trees and grass. Where would you rather hang out on a hot summer day on the top of building or in a park with trees and green grass? While scientists do believe that turbines could impact climate, it is small in comparison to fossil fuels, which are playing a much larger negative impact on climate and pollution to the environment. So which energy resource is cleaner?
Learn how wind turbines produce electricity here: http://www1.eere.energy.gov/windandhydro/wind_how.html
The next and final part of the Clean Energy 101 series will be on geothermal and biomass energy sources.
Thanks again to Michael Haughey for his consulting work on this article.
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Upcoming events:
Vestas Job Fair in Brighton:
BRIGHTON - Vestas Nacelles America Inc. is beginning the employee search for its new factory under construction in Brighton, the company's first nacelle factory in the United States.
Vestas is working with SOS Staffing to hire hourly production and warehouse positions. Toward that end, the firms will hold a Career and Information Forum on Sept. 24 at the Adams Count Fairgrounds' Waymire Building, 9755 Henderson Road in Brighton.
Three sessions will be held (8 to 10 a.m.; noon to 2 p.m.; and 6 to 8 p.m.), all focusing on production and warehouse positions. All jobs are full-time, direct hire with benefits. Vestas representatives will be onsite all day to answer questions and provide information.
Interested parties are asked to visit www.sosstaffing.com/vestas and submit a resume or application. More information is available from SOS Staffing at the following branch offices:
• Fort Lupton - 303-857-2358
• Greeley - 970-353-2220
• Longmont - 303-772-7422
• Fort Collins - 970-282-4401
E-mail vestasnac@sosstaffing.com to get updates on current application status.
Earthworks Expo
Transition has a HUGE presence at this year’s Earthworks Expo
at the Denver Merchandise Mart the weekend of August 22 and 23!
Join Transition Denver and Transition Colorado and other local initiatives from around the state at the third annual EarthWorks Expo, Denver's largest authentically local sustainable-living event of the year, a celebration of Colorado's green marketplace and an inspiring showcase of local solution-providers in renewable energy, green building, green transportation, resource conservation and Earth-friendly products and services.
Transition Denver will Join Transition Colorado
in delivering a series of workshops and panels.
Adam Brock and Kenzie Davison will be doing a Permaculture workshop and Dana Miller will be leading a panel on Urban Agriculture and the Grow Local Colorado Campaign. The panel will include Lisa Rogers of Feed Denver, Celia Curtis of Denver Botanic Gardens and James Bertini of Denver Urban Homesteading.
Transition Colorado will have a booth (#503) – come by and see how the movement is unfolding in our state!
Check out http://www.earthworks2009.com/workshops.html for full schedule of Earthworks Expo workshops.
EXPO FEATURES
• 150 Green Exhibitors
• World-class Speakers
• 42 Great Workshops
• Real Solutions for Going Green
• Special Programs for Kids
• Organic & Vegetarian Food
• Zero-waste, Low-carbon Event
• Low Admission Price & Free Parking
