Comment: People of Virginia, turn to True Green Power, Nuke Power is not green or an alternative energy, Uranium is not green or renewable!!! No Nuke Power, No Uranium Mining!
Radhika ReddyGo to Radhika's Home Page
Portland DIY Environmentalism Examiner
May 24, 2:57 PM
Earth wind and fire: the state of renewable energy and how to bring it home.
In case you haven’t heard, fossil fuels are dirty, dangerous, dwindling, and frankly, kind of uncool. Although the door to traditional carbon-based energy sources is far from closed, the door to green technologies has blown wide open in recent years. Seven percent of US power came from renewable sources in 2007—mainly biomass (biofuels) and hydroelectric. But solar, wind, geothermal, and wave energy are moving up and shaking up the business-as-usual mind set of the energy sector. Here’s a peeping tom’s glance at the power and potential of naked energy.
Here Comes the Sun…
Solar energy has been in use since before the first sea creature sprouted legs and walked on land. Plants use the sun to turn carbon dioxide into food. Your grandparents probably used it turn wet clothes into dry ones. But beyond its conventional function as a direct heat and light source, the potential for solar energy is enormous. One hour of sunlight hitting the earth is commonly estimated to contain enough energy to meet global demand for an entire year.
As interest in alternative energy grows, so do methods for harnessing and delivering it. Once thought too expensive to be practical, solar energy gets cheaper with each passing year of technology development. McKinsey & Company, an international management consulting firm dealing in energy, projects the unsubsidized cost of solar energy is a scant three to seven years away from “grid parity”—that is to rival the affordability of traditional energy sources.
Sunlight is energy in the form of electromagnetic radiation. Much like a beach can be broken down into individual particles of sand, the basic unit of electromagnetic radiation is the photon. A photovoltaic (PV) cell, or solar cell, is a sheet of light-absorbing material which converts photons into electricity through a process called the photovoltaic effect. When photons from sunlight are absorbed into a solar cell, they displace a stream of electrons and generate direct current (DC) electricity which can be stored or funneled into the power grid.
Although the first solar cell was created in the late 1800s from selenium and gold, it was the accidental discovery of silicon’s light absorbing properties in the 1950s which inspired solar power technology as we know it. Solar cell efficiency is determined by its ability to collect photons and by how much electricity can be harnessed from each of those photons. Science fictionesque inventions, ranging from solar cell balloons to grids of solar panels in space which beam energy back to earth in the form of microwaves, are promising but years away from making a practical contribution to the grid.
More immediate technologies, such as higher efficiency light absorbing materials, cells which adjust their position according to the changing angle of the sun, and sun concentrating cell designs, are bringing costs down. Despite these advancements, the US Department of Energy (DOE) reports that photovoltaic power plants made up less than one percent of renewable contributions to the total energy supply in 2007.
While its commercial impact has been modest, solar energy has great potential for a motivated consumer. Solar powered calculators or solar kits to charge cell phones, MP3 players, and other portable devices already enjoy widespread use. On a grander scale, hardwiring a new home with a 2.5 kilowatt solar power system would add $13,000 to $15,000 to the cost of a California home, according to online technology forum, cnet.com. This translates to $105 per month on a 30-year mortgage at 6.75 percent and would meet 30–60 percent of the average household’s energy needs. The increased housing payment would be offset by reduced utility payments.
Retrofitting an existing home with solar power is also possible. A three-part series on the PBS television program Nova documented the conversion of a 1960s southern California house into a zero energy home (excluding cooking gas). After incentive and tax rebates, the total cost of going solar was $43,000. The homeowners estimate that they will make their money back in seven years of saved energy bills and auto fuel. Furthermore, their unused energy is funneled back into the southern California power grid, earning the owners $200–$300 a year in credit.
Blowin’ in the Wind …
Man has been using wind as his workhorse for over a millennium. As early as the ninth century, vertical-axle windmills were used to grind grains and siphon water in Persia. Modern versions of these were seen in Europe toward the end of the twelfth century. The latest descendent of the windmill, the wind turbine, is popping up all over the world as a legitimate source of renewable energy.
Airplane-wing technology has made modern turbine propeller blades more efficient than their predecessors. Additionally, the turbines are mechanized to turn to face the wind, further improving energy collection. Current models are able to harness about 50 percent of the energy in wind, rapidly approaching the 59 percent theoretical limit. Most appealingly, wind farms require no fuel and have zero emissions. Wind’s major drawback, like solar, is its dependency on the weather. Power cannot be generated when wind is not blowing. In addition, stronger winds are generally found far from cities where it is needed the most.
To the average consumer this means a commercial turbine producing two megawatts (MW) costs $3.5 million. Its smaller 10 kilowatt (kW) cousin is strong enough to power an average household and will set you back $40,000 to $70,000. But even the residential variety turbine is not something an urban dweller could simply plant in their postage-stamp-sized backyard. The 10 kW model sold by the Oklahoma-based Bergey Windpower Company is 23 feet in diameter and installed on an 80–100 foot tower. Such a behemoth structure would be restricted by most urban zoning laws. Other cons include noise pollution and a questionable aesthetic. However if you have a lot of space and an agreeable neighborhood association, it’s an option worth considering. Over its estimated life span of 30 years, a residential turbine will save Mother Earth from 1.2 tons of air pollutants and 200 tons of greenhouse gases. To seriously consider this option, look into your local zoning regulations.
US wind use pales in comparison to that of Denmark and Spain, whose wind power respectively accounts for 20 percent and 10 percent of their energy consumption.
The American Wind Energy Association reports wind accounting for 1 percent of US energy in 2008, serving the equivalent of 4.5 million American households. The market hasn’t even skimmed the surface of its potential according to a recent Stanford University report claiming that wind contains enough energy to meet global demand 35 times over. And to these kinds of numbers governments are starting to listen. The European Union hopes wind power will meet 20 percent of its energy needs by 2020—a benchmark the US Department of Energy (DOE) wants to meet by 2030.
And it burns, burns, burns, burns…
The burning core of our planet is the root of geothermal power, which uses heat stored beneath the earth’s surface. The deeper you go, the hotter it gets, peaking at a scorching 9932° F at the core. Archeologists suspect that geothermal heat has been used by humans for a many as 10,000 years. Indigenous populations used North American hot springs for bathing and therapeutic purposes.
In 1904 a modern incarnation of this technology took the form of a generator built on a dry steam field by the Italian Prince Conti. Although his invention illuminated only four light bulbs, the concept evolved into the first industrial geothermal power plant. In 1922 American John Grant powered his famous Californian resort, The Geysers, with a geothermal plant. The plant became defunct but was later redeveloped and is now home to 21 geothermal plants. Although The Geysers pumps out 750 MW of energy, geothermal accounts for less than 1 percent of American energy. More impressive international success stories include the Philippines, whose government reports 27 percent of its energy coming from geothermal.
Geothermal plants are diverse in their specific technologies. The most common binary-cycle type uses hot geothermal water to vaporize a second fluid with a lower boiling point. The resulting steam drives an energy-harvesting turbine. Because water is depleted, this is not technically a renewable resource. However water loss can be managed with methods like reinjection into the ground. The Geysers uses treated sewage water from nearby Santa Rosa, simultaneously creating renewability and providing a solution for city waste. A 2007 Wall Street Journal article reports geothermal plants leave smaller footprints than even solar or wind plants. Carbon emissions weigh in around 10 percent of those produced by typical coal-burning plant, according to one EPA report. Perhaps most attractive, geothermal energy is available irrespective of weather the wind blows or the sun shines.
Given the offset of the water consumption by the other green features, the technology is included in the green category, getting favorable nods from environmental advocacy groups such as Sierra Club and Greenpeace. Like wind and solar, geothermal offers consumers a residential option in the form of heat pumps, specifically ground-source heat pumps (GHPs). They capitalize on the constant and moderate temperature of the Earth’s surface. Regardless of sweltering or frigid weather forecasts, the majority of the planet maintains a constant 50–60° F in its first three meters underground.
GHPs work via water-filled pipes running below the frost line which transfer the Earth’s heat to a pump. This pump extracts heat and delivers it to the home through air ducts. Some GHPs use this technology in reverse to cool in the summertime and still others can also provide residential hot water.
The efficiency of the system relative to air source systems comes first from the use of water, which gains and loses heat more efficiently than air. The second point of efficiency comes from the nature of ground water temperatures, which tend to be more moderate than air temperatures during the hot summer or cold winter.
In spite of the electricity required to operate the pump, the Environmental Protection Agency (EPA) estimates that GHPs can reduce energy consumption by up to 70 percent of traditional residential heating methods. The US DOE reports a typical GHP installation will pay for itself in five to ten years via energy-bill savings. Although GHPs can be installed in both new and existing houses, retrofitting may not be possible in homes whose ductwork is incompatible with the system. Tips for installation are available at the Energy Efficiency and Renewable Energy agency’s website:
Catch a Wave and You’re Sitting on Top of the World …
Lagging behind the renewable energy pack is wave power. Like geothermal, wind, and solar, the ocean’s waves have enough power to meet global energy demands and then some. Nonetheless, commercial wave farms didn’t appear until late 2007 off the coast of Portugal.
Steven Salter, a Scottish engineer, developed the first wave generator in the mid 1970s. The invention was a string of large canisters, called Salter’s Duck, tethered to the ocean floor. A generator and hydraulics extracted electricity from the wave-powered rocking motion of these canisters.
Though technological refinements made wave power price-competitive with nuclear power, by the early 1980s the British government shut down the project without ever testing the Salter’s Duck in the open ocean. Some believe this decision was influenced by nuclear industry lobbyists.
Building off Salter’s ideas, the current Portuguese installment makes use of wave-powered undulations with flexible horizontal pipe. The resulting displacement of hydraulic fluid at the pipes’ hinges drives an energy-collecting turbine. Another technology, called the AquabuOY, is in development off the coast of California. The AquabuOY is a vertical tube whose wave powered bouncing pressurizes water and drives a turbine.
Major obstacles in wave technology development include designing hardware that can withstand the physical assault of ocean storms, transporting equipment to the open sea, and transporting power from the wave farms back to the grid. Environmental concerns include possible hydraulic fluid leaks and disturbance of marine life—neither of which are insurmountable barriers. Wave power is a relatively young technology and like any child, its potential for growth is still untapped.
So whether it comes on a wave, from the ground, through the air, or from the sun, it’s clear that the benefits of getting naked (with energy that is) are many. A future with renewable, sustainable energy foretells an economy without dependence on foreign oil and with the potential to actually export energy. Add to the mix the creation of new and better quality jobs (maybe it’s time to hang up the dangerous coal miner hats?) and a cleaner, safer environment and the potential is as clear as the air that we might someday breathe.
http://www.examiner.com/x-8364-Portland-DIY-Environmentalism-Examiner~y2009m5d24-Renewable-energy-at-home
Portland DIY Environmentalism Examiner
May 24, 2:57 PM
Earth wind and fire: the state of renewable energy and how to bring it home.
In case you haven’t heard, fossil fuels are dirty, dangerous, dwindling, and frankly, kind of uncool. Although the door to traditional carbon-based energy sources is far from closed, the door to green technologies has blown wide open in recent years. Seven percent of US power came from renewable sources in 2007—mainly biomass (biofuels) and hydroelectric. But solar, wind, geothermal, and wave energy are moving up and shaking up the business-as-usual mind set of the energy sector. Here’s a peeping tom’s glance at the power and potential of naked energy.
Here Comes the Sun…
Solar energy has been in use since before the first sea creature sprouted legs and walked on land. Plants use the sun to turn carbon dioxide into food. Your grandparents probably used it turn wet clothes into dry ones. But beyond its conventional function as a direct heat and light source, the potential for solar energy is enormous. One hour of sunlight hitting the earth is commonly estimated to contain enough energy to meet global demand for an entire year.
As interest in alternative energy grows, so do methods for harnessing and delivering it. Once thought too expensive to be practical, solar energy gets cheaper with each passing year of technology development. McKinsey & Company, an international management consulting firm dealing in energy, projects the unsubsidized cost of solar energy is a scant three to seven years away from “grid parity”—that is to rival the affordability of traditional energy sources.
Sunlight is energy in the form of electromagnetic radiation. Much like a beach can be broken down into individual particles of sand, the basic unit of electromagnetic radiation is the photon. A photovoltaic (PV) cell, or solar cell, is a sheet of light-absorbing material which converts photons into electricity through a process called the photovoltaic effect. When photons from sunlight are absorbed into a solar cell, they displace a stream of electrons and generate direct current (DC) electricity which can be stored or funneled into the power grid.
Although the first solar cell was created in the late 1800s from selenium and gold, it was the accidental discovery of silicon’s light absorbing properties in the 1950s which inspired solar power technology as we know it. Solar cell efficiency is determined by its ability to collect photons and by how much electricity can be harnessed from each of those photons. Science fictionesque inventions, ranging from solar cell balloons to grids of solar panels in space which beam energy back to earth in the form of microwaves, are promising but years away from making a practical contribution to the grid.
More immediate technologies, such as higher efficiency light absorbing materials, cells which adjust their position according to the changing angle of the sun, and sun concentrating cell designs, are bringing costs down. Despite these advancements, the US Department of Energy (DOE) reports that photovoltaic power plants made up less than one percent of renewable contributions to the total energy supply in 2007.
While its commercial impact has been modest, solar energy has great potential for a motivated consumer. Solar powered calculators or solar kits to charge cell phones, MP3 players, and other portable devices already enjoy widespread use. On a grander scale, hardwiring a new home with a 2.5 kilowatt solar power system would add $13,000 to $15,000 to the cost of a California home, according to online technology forum, cnet.com. This translates to $105 per month on a 30-year mortgage at 6.75 percent and would meet 30–60 percent of the average household’s energy needs. The increased housing payment would be offset by reduced utility payments.
Retrofitting an existing home with solar power is also possible. A three-part series on the PBS television program Nova documented the conversion of a 1960s southern California house into a zero energy home (excluding cooking gas). After incentive and tax rebates, the total cost of going solar was $43,000. The homeowners estimate that they will make their money back in seven years of saved energy bills and auto fuel. Furthermore, their unused energy is funneled back into the southern California power grid, earning the owners $200–$300 a year in credit.
Blowin’ in the Wind …
Man has been using wind as his workhorse for over a millennium. As early as the ninth century, vertical-axle windmills were used to grind grains and siphon water in Persia. Modern versions of these were seen in Europe toward the end of the twelfth century. The latest descendent of the windmill, the wind turbine, is popping up all over the world as a legitimate source of renewable energy.
Airplane-wing technology has made modern turbine propeller blades more efficient than their predecessors. Additionally, the turbines are mechanized to turn to face the wind, further improving energy collection. Current models are able to harness about 50 percent of the energy in wind, rapidly approaching the 59 percent theoretical limit. Most appealingly, wind farms require no fuel and have zero emissions. Wind’s major drawback, like solar, is its dependency on the weather. Power cannot be generated when wind is not blowing. In addition, stronger winds are generally found far from cities where it is needed the most.
To the average consumer this means a commercial turbine producing two megawatts (MW) costs $3.5 million. Its smaller 10 kilowatt (kW) cousin is strong enough to power an average household and will set you back $40,000 to $70,000. But even the residential variety turbine is not something an urban dweller could simply plant in their postage-stamp-sized backyard. The 10 kW model sold by the Oklahoma-based Bergey Windpower Company is 23 feet in diameter and installed on an 80–100 foot tower. Such a behemoth structure would be restricted by most urban zoning laws. Other cons include noise pollution and a questionable aesthetic. However if you have a lot of space and an agreeable neighborhood association, it’s an option worth considering. Over its estimated life span of 30 years, a residential turbine will save Mother Earth from 1.2 tons of air pollutants and 200 tons of greenhouse gases. To seriously consider this option, look into your local zoning regulations.
US wind use pales in comparison to that of Denmark and Spain, whose wind power respectively accounts for 20 percent and 10 percent of their energy consumption.
The American Wind Energy Association reports wind accounting for 1 percent of US energy in 2008, serving the equivalent of 4.5 million American households. The market hasn’t even skimmed the surface of its potential according to a recent Stanford University report claiming that wind contains enough energy to meet global demand 35 times over. And to these kinds of numbers governments are starting to listen. The European Union hopes wind power will meet 20 percent of its energy needs by 2020—a benchmark the US Department of Energy (DOE) wants to meet by 2030.
And it burns, burns, burns, burns…
The burning core of our planet is the root of geothermal power, which uses heat stored beneath the earth’s surface. The deeper you go, the hotter it gets, peaking at a scorching 9932° F at the core. Archeologists suspect that geothermal heat has been used by humans for a many as 10,000 years. Indigenous populations used North American hot springs for bathing and therapeutic purposes.
In 1904 a modern incarnation of this technology took the form of a generator built on a dry steam field by the Italian Prince Conti. Although his invention illuminated only four light bulbs, the concept evolved into the first industrial geothermal power plant. In 1922 American John Grant powered his famous Californian resort, The Geysers, with a geothermal plant. The plant became defunct but was later redeveloped and is now home to 21 geothermal plants. Although The Geysers pumps out 750 MW of energy, geothermal accounts for less than 1 percent of American energy. More impressive international success stories include the Philippines, whose government reports 27 percent of its energy coming from geothermal.
Geothermal plants are diverse in their specific technologies. The most common binary-cycle type uses hot geothermal water to vaporize a second fluid with a lower boiling point. The resulting steam drives an energy-harvesting turbine. Because water is depleted, this is not technically a renewable resource. However water loss can be managed with methods like reinjection into the ground. The Geysers uses treated sewage water from nearby Santa Rosa, simultaneously creating renewability and providing a solution for city waste. A 2007 Wall Street Journal article reports geothermal plants leave smaller footprints than even solar or wind plants. Carbon emissions weigh in around 10 percent of those produced by typical coal-burning plant, according to one EPA report. Perhaps most attractive, geothermal energy is available irrespective of weather the wind blows or the sun shines.
Given the offset of the water consumption by the other green features, the technology is included in the green category, getting favorable nods from environmental advocacy groups such as Sierra Club and Greenpeace. Like wind and solar, geothermal offers consumers a residential option in the form of heat pumps, specifically ground-source heat pumps (GHPs). They capitalize on the constant and moderate temperature of the Earth’s surface. Regardless of sweltering or frigid weather forecasts, the majority of the planet maintains a constant 50–60° F in its first three meters underground.
GHPs work via water-filled pipes running below the frost line which transfer the Earth’s heat to a pump. This pump extracts heat and delivers it to the home through air ducts. Some GHPs use this technology in reverse to cool in the summertime and still others can also provide residential hot water.
The efficiency of the system relative to air source systems comes first from the use of water, which gains and loses heat more efficiently than air. The second point of efficiency comes from the nature of ground water temperatures, which tend to be more moderate than air temperatures during the hot summer or cold winter.
In spite of the electricity required to operate the pump, the Environmental Protection Agency (EPA) estimates that GHPs can reduce energy consumption by up to 70 percent of traditional residential heating methods. The US DOE reports a typical GHP installation will pay for itself in five to ten years via energy-bill savings. Although GHPs can be installed in both new and existing houses, retrofitting may not be possible in homes whose ductwork is incompatible with the system. Tips for installation are available at the Energy Efficiency and Renewable Energy agency’s website:
Catch a Wave and You’re Sitting on Top of the World …
Lagging behind the renewable energy pack is wave power. Like geothermal, wind, and solar, the ocean’s waves have enough power to meet global energy demands and then some. Nonetheless, commercial wave farms didn’t appear until late 2007 off the coast of Portugal.
Steven Salter, a Scottish engineer, developed the first wave generator in the mid 1970s. The invention was a string of large canisters, called Salter’s Duck, tethered to the ocean floor. A generator and hydraulics extracted electricity from the wave-powered rocking motion of these canisters.
Though technological refinements made wave power price-competitive with nuclear power, by the early 1980s the British government shut down the project without ever testing the Salter’s Duck in the open ocean. Some believe this decision was influenced by nuclear industry lobbyists.
Building off Salter’s ideas, the current Portuguese installment makes use of wave-powered undulations with flexible horizontal pipe. The resulting displacement of hydraulic fluid at the pipes’ hinges drives an energy-collecting turbine. Another technology, called the AquabuOY, is in development off the coast of California. The AquabuOY is a vertical tube whose wave powered bouncing pressurizes water and drives a turbine.
Major obstacles in wave technology development include designing hardware that can withstand the physical assault of ocean storms, transporting equipment to the open sea, and transporting power from the wave farms back to the grid. Environmental concerns include possible hydraulic fluid leaks and disturbance of marine life—neither of which are insurmountable barriers. Wave power is a relatively young technology and like any child, its potential for growth is still untapped.
So whether it comes on a wave, from the ground, through the air, or from the sun, it’s clear that the benefits of getting naked (with energy that is) are many. A future with renewable, sustainable energy foretells an economy without dependence on foreign oil and with the potential to actually export energy. Add to the mix the creation of new and better quality jobs (maybe it’s time to hang up the dangerous coal miner hats?) and a cleaner, safer environment and the potential is as clear as the air that we might someday breathe.
http://www.examiner.com/x-8364-Portland-DIY-Environmentalism-Examiner~y2009m5d24-Renewable-energy-at-home
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