Solar energy includes multiple technologies, some are known as passive and some are known as active. Passive technologies include technologies for designing a home to take advantage of natural sunlight for heating and lighting and active technologies include adding equipment to your home for producing electricity or hot water. Two common technologies that you can add to your home are a solar hot water that uses the sun to heat water and a solar photovoltaic (PV) that uses the sun to generate electricity. In addition, Concentrated Solar Power or CSP uses focused solar energy to generate heat for the turning of a turbine for generating electricity. This is used on a commercial scale to produce power for utilities. Solar energy is a highly reliable and proven technology for producing clean energy.
In recent years, the solar industry has seen tremendous growth as more individuals, businesses, and utilities are beginning to realize the practicality and affordability of solar energy.
For residential or commercial projects, a good quality professionally installed solar PV system can outlast many components of a building structure with little maintenance. Solar hot water is less expensive than solar PV and often has a quicker return on investment, but has more maintenance involved. Solar can be installed anywhere that you have a south-facing location that is not shaded.
In addition to residential usage, utilities across the country, including in the Southeast, are beginning to propose and develop large-scale or Megawatt (MW) scale projects to provide power to their customers.
Photovoltaic (PV) technology turns sunlight directly into electricity. While the capital cost of installing photovoltaic equipment is high, the fuel (sunlight) is limitless and free. In addition, photovoltaic modules provide an excellent added value to your home. Many financial institutions are even providing the option of including the cost of PV or solar hot water into new home mortgages making it easier to finance. A solar system will provide the biggest benefit and the quickest payback to customers who have already diligently retrofitted their homes with energy efficiency measures.
There are two types of photovoltaic modules: crystalline and thin film. While thin film is cheaper and more flexible, at this time the majority of the solar market installs crystalline PV panels because of the high levels of efficiency and long-term reliability of this technology.
Solar hot water systems use direct heat from the sun to heat water to useful temperatures for the home or business. Currently, solar hot water systems are used for a wide variety of needs from hot water for your kitchen or swimming pool to being used for heating your home. Solar hot water and a solar PV system complement each other when installed together.
If you are thinking about installing a solar PV or solar hot water on your home or building there are a few important steps that you need to take.
First, have you made all possible energy efficiency improvements to your home? Solar systems are an expensive improvement to your home and the less energy your home uses the smaller the system that you will need to purchase. Always invest in energy efficiency improvements first as this is the best use of your money.
Second, figure out what incentives are in your state, visit this website which provides a state by state listing of all renewable energy tax incentives and other associated laws in the nation.
The third and most important step is finding an experienced and qualified solar installer. Hiring the right solar installer is your best bet for making sure you have a high performing system and a good experience. For a list of nationally certified solar installers in your state, please visit the National American Board of Certified Energy Practitioners. This website provides one simple way for individuals interested in residential or commercial solar applications to identify certified installers in their area. Another widely supported resource for finding a solar installer is Find Solar.
Finally, while some systems use a battery back up and are not connected to the power grid, most systems today use the grid to provide power and back up to the solar system. It is possible to use both the grid and a battery back up for outages but this makes systems more expensive. Contact your local utility to interconnect your PV system onto the utility grid. In some instances utilities actively want solar into their system, but some utilities with little experience with solar might not be enthused and will need to be educated on the benefits of solar energy. Typically, a contract agreement is arranged prior to the grid tie that determines how much they are willing to 'pay' for the excess power you generated. Contact your local utility to find out details on this program in your area.
Expanding the use of solar energy has many benefits including cleaner air, economic development, national security and the prevention of emissions that effect climate change.
When faced with energy outages and electricity price increases, homeowners can really benefit from the added economic value and security of installing either a solar thermal or solar PV system to their home or business.
In addition, large-scale solar projects can complement other renewable energy projects already being implemented by utility companies. For example, a hybrid system of wind and solar energy can help reduce some fluctuations that can occur in the energy being produced by either system.
- In the U.S., there are about 400 coal-burning power plants with about 1000 boilers.
- Only one-half the coal plants in the U.S. have scrubbers that limit acid rain effects, air pollution, and regional haze.
- In the U.S. air, coal plants emit 2/3 of the SO2, 1/5 of the NO2, ½ of the mercury, and 8-10% of the particulate matter.
Coal plants have one the largest environmental footprints on this planet of any industrial facility. From the destructive mining practices that extract coal from mountaintops to the burning of coal at the power plant, coal is undoubtedly one of the most risky of energy practices. Coal-fired power plants release mercury pollution that contaminates our lakes and rivers, making recreation and eating fish unhealthy. Airborne mercury emissions eventually find their way into water sources, generally through rainfall. In addition, coal plants are huge water hogs, requiring vast amounts of water to produce electricity. In fact, coal plants are second only to nuclear power plants in terms of water intensity and compete with agriculture and people for valuable water resources.
Coal plants produce soot and smog-forming pollution (sulfur dioxide and nitrogen oxides) that are leading contributing factors to respiratory diseases like asthma and to poor air quality. Coal plants also emit a plethora of hazardous air pollutants (HAPs) - otherwise known as toxics.
In the United States, coal-fired power plants, whose carbon dioxide emissions are uncontrolled, represent the single largest source of carbon dioxide - the main global warming pollution. Proposed new coal plants do not have the technology to capture carbon dioxide.
The price of coal has more than doubled over the past 5 years and is expected to continue increasing, making coal plants highly cost-inefficient. Ratepayers are the ones actually responsible for paying for these coal plants because the utility companies are passing their expenses on to their customers. Investing in coal is also a risky proposition for utility companies due to the likelihood of federal regulations on carbon dioxide pollution.
Finally, you may have heard of the term Clean Coal. There is no such thing as Clean Coal. It is simply a marketing program by the coal industry to convince consumers that they should continue to invest in coal mining. Clean coal does not exist except in the words of advertising slogans.
Bio-fuels are created from agricultural waste and residues, forestry residues, oil-crops, animal fats, and waste oil. They are converted to liquid or gaseous fuels, such as biodiesel, ethanol, and methanol.
Biodiesel and ethanol are used across the country in automobiles, school bus fleets, construction and agriculture equipment, and all branches of the U.S. military. You may have noticed the signs at the gas pumps that tell you that the gas you are putting in your vehicle is approximately 10% ethanol.
The critical issues for bio-fuels are:
- Do they convert valuable cropland that could be used for food and thus drive up the cost of food as the expense of poorer consumers?
Do they have a transportation network that adds to the cost? In other words, bio-fuels may be an acceptable energy choice if their use is close to where they are produced such as a farm, but not if they have to be transported long distances.]