About Renewable Energy

Almost all forms of terrestrial energy, such as fossil fuels, solar, wind, ocean thermal, and hydropower, can be traced back to energy received from the sun's fusion reactions. The only exceptions are tidal, nuclear, and geothermal power. Tidal energy comes from the gravitational potential energy of the Earth/Moon system. Geothermal energy is believed to be generated primarily by radioactive decay inside the Earth.

Most human energy sources today use energy from sunlight, in the form of fossil fuels (coal, oil and gas). Once the stored forms are used up then the long-term energy usage of humanity is limited to that from the sunlight falling on Earth. The total energy consumption of humanity today is equivalent to about 0.1-0.01 percent of that. Every hour of every day, more solar energy reaches the earth than the entire world's population consumes in a year by all energy sources.

The term renewable energy encompasses a broad spectrum of technologies based on self-renewing energy sources, such as sunlight, wind, flowing water, the earth's internal heat, and biomass (energy crops, agricultural, forest and industrial waste, and municipal waste). These resources can be used to produce electricity for all economic sectors, transportation fuels, and heat for buildings and industrial processes.

Renewable energy offers important benefits compared to conventional energy sources, such as fossil fuels or nuclear power. Renewable-energy resources are abundant; worldwide, one-thousand-times more energy reaches the surface of the earth from the sun than is released today by all fossil fuels consumed. Like fossil fuels, renewable-energy resources are unevenly distributed throughout the world. However, every region has some renewable-energy resource. And, because different kinds of renewable-energy resources complement each other, taken together they can contribute appreciably to development and energy security in every nation--without dependence on foreign energy sources subject to political instability and manipulation. (Wikipedia)

Renewable-energy systems generate little, if any, waste or pollutants that contribute to acid rain, urban smog, and health problems, nor do they spawn environmental cleanup costs and waste-disposal fees. Systems using solar, wind, or geothermal sources do not contribute any carbon dioxide to the atmosphere.

Three methods by which solar energy can be employed to lower utility bills and reduce the consumption of fossil fuels: passive solar, solar electric, and solar thermal. Since solar energy is relatively expensive, it is imperative to first reduce all loads through energy efficiency measures.

Passive Solar

Passive solar systems use non-mechanical techniques of capturing, converting and distributing sunlight into useable forms of energy such as heating, lighting or ventillation. These techniques include selecting materials with favorable thermal properties, designing spaces that naturally circulate air and referencing the position of a building to the sun. Building elements are designed with reference to the location of the sun in the sky throughout the daily and seasonal cycles. For example, south facing windows allow the low winter sun to shine into the building, heating the surfaces and warming the air. Overhangs over these windows serve to block the high summer sun, keeping the building cooler in the summer.

Solar Electric (Photovoltaics)

Photovoltaic devices use semiconductor materials, such as silicon, to convert sunlight to electricity. They contain no moving parts and produce no emissions. They can be used in small cells, panels, and arrays. Photovoltaic systems require little servicing or maintenance and have typical lifetimes of about twenty years. Solar panels that are mounted on the roof or ground and can also be incorporated into building elements such as walls, roof, or awnings. The electricity produced is DC and must be converted to AC with an inverter for use by most appliances. The inverter may be connected to the electric grid and, if your utility offers net metering, feed any excess solar electricity into the grid during the day and draw electricity from the grid at night. Alternatively, batteries are used to store enough electricity during the day for use at night and during cloudy periods.

Solar Thermal

Solar thermal systems use the sun's heat to meet a variety of needs that include heating water for industrial processes, domestic water supplies, and community swimming pools; generating electricity; preheating building ventilation air; and directly heating building interiors. One of the most widespread uses of solar thermal technology is solar water heating. Significant progress has been made in improving the reliability and durability of these systems in recent decades. According to the Solar Energy Industries Association, more than 200,000 businesses and 100,000 pools in the United States now use solar thermal systems to reduce utility bills. Most commonly, a solar thermal system is comprised of collectors, storage tanks, piping, pumps, and controls. The collectors (or panels) are mounted on the roof, ground, or attached to a wall.

Wind

Wind-power systems convert the kinetic energy of the wind into other forms of energy, such as electricity. Although wind-energy conversion is relatively simple in concept, design of the turbines required can be quite complex. Rapid progress in wind-energy technology has reduced costs until they are almost competitive with the costs of conventional power. Wind resources are abundant throughout the world. In the United States, a good quantity of wind resources can be found in 34 states. For example, the wind in North Dakota alone could supply as much as 36 percent of all the electricity consumed by the lower 48 states.

Geothermal

Geothermal resources include dry steam, hot water, hot dry rock, magma, and ambient ground heat. Steam and water resources are used for commercial power generation and ambient ground heat is used commercially in geothermal heat pumps. The Geysers steam-power plant in California is the world's oldest and largest geothermal power plant, with a capacity of 2,000 MW. Hot water plants are now the major source of geothermal power in the world.

Why Renewable Energy

Save Money

Investing in a renewable energy system for your home or business will allow you to lower your energy cost and save money over time. Protect yourself from future utility rate increases and significantly reduce your monthly utility costs indefinitely. As costs go up, however, so do your renewable energy s avings. Increase the value of your property. Based on a recent study by ICF consulting, energy saving measures such as solar can add up to $20 of home value for every $1 of yearly energy cost savings. The increase in your home value can go up by 20%.

Power Reliability

One of the trends we are seeing in today's word is frequent black-outs and brown-outs. The first solar systems built and designed in the 1950's are not only still functional but produce significant power even now! When NASA needed trouble free, durable power for the space race, satellites and for the exploration of other planets they turned to solar.

Protect the Environment

Scientists have been collecting data for decades on the effects of burning carbon-based fuel and how that impacts our atmosphere and environment. Carbon-based fuels are petroleum, gasoline, natural gas, coal, wood, and household trash. When we think about lighting our homes, we usually just think about flipping the light switch. Unfortunately, without even realizing it, we are more than just lighting our homes; we are changing the climate of the entire planet. The more all of us invest in a renewable energy future, the better chance we all have of continuing to enjoy life on our beautiful planet and protect our children's future as well.

National Security

Some of the world's largest oil deposits exist in the Middle East and Northern Africa. The U.S. is dependent upon energy resources that are located in a region where war and political instability have become common place. More U.S. soldiers have been lost in the war in Iraq than those lives lost on September 11, 2001. When we know that we can provide for ourselves, with the resources availabe to us within our own homeland, we can put some of our fears to rest.