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Solar Energy

From an environmental perspective, solar power is the best thing going. A 1.5 kilowatt PV system will keep more than 110,000 pounds of carbon dioxide, the chief greenhouse gas, out of the atmosphere over the next 25 years. The same solar system will also prevent the need to burn 60,000 pounds of coal. With solar, there’s no acid rain, no urban smog, no pollution of any kind.
Mankind has been crazy to have not bothered to harness the sun’s energy until now. Think about this. Go outside on a sunny day. The light falling on your face left the Sun just 8 minutes go. In that 8 minutes it traveled 93 million miles. Those photons are hauling and when they strike your PV module you can convert that motion to electricity. As technology, photovoltaics are not as glitzy as that new sport utility vehicle the television tells us to crave. But in many ways PV is a much more elegant and sophisticated technology.

Whether it be for your business or for your home, why not invest in Solar Panels.Today’s solar panels are bombproof and often come with a 25 year warranty or more. Your solar panels may outlive you. They are also modular—you can start with a small system and expand it over time. Solar panels are light (weighing about 20 pounds), so if you move you can take the system with you.

Grid interactive systems and net metering

Some utilities object to net metering. Usually the issue isn’t money, but control. They don’t want your juice on their wires or they don’t want to set a precedent that could come back to haunt them. There are some distributed generation technologies coming down the pike that utilities definitely won’t want to net meter, including fuel cells and 50 kw microturbines the size of beer kegs. However in the USA and Australia electricity suppliers are becomg more supportive of solar enegy buy back schemes.Also busineses can now take advantage of different suppliers of both gas and electricity and shop for the most economical.

Solar advocates delight in bashing utilities. But for all its faults, the industry has strung an amazing amount of wire. Rarely is an American or an Australian, or a European more than 50 feet from an electrical outlet. It’s an everyday miracle we take for granted. From an engineering perspective, the grid is a tremendous resource. A grid-tied PV system will be more efficient, arguably greener, and certainly cheaper than a backwoods one. More efficient because the inverter can track the modules “maximum power curve” rather than the lower voltage needed to recharge batteries. Arguably greener because you don’t need batteries, which contain caustic chemicals, emit sulfurous gases, and eventually wear out. And much cheaper because, with the grid as backup, you don’t have to buy batteries, charge controller, control panel or generator.Right there, you’ve knocked up to $5,000 off a typical stand-alone system. Getting the price down is critical, because no one on the grid needs PV, at least not in the same way an off-grid homeowner needs it. We’ve already got juice. It may be from a nuke, it may be from a coal plant, it may be hydro (or “embodied salmon”), but it’s there. To sell grid-connected PV systems you’ve got to get the price down and then help prospective customers understand that solar is to coal as a croissant is to a Twinkie. On a gut level, many people already grasp the key difference between fossil fuels and renewable energy. One is stealing from our kids, the other isn’t.

The current cost of solar panels means that grid-interactive systems do not pay for themselves in terms of the cost saving when compared with electricity from the grid. In spite of this, many people with grid connected houses are choosing to install grid-interactive solar systems, as they do not create any greenhouse gases when generating electricity, unlike coal-fired power plants. Numerous studies have demonstrated that the equivalent amount of electricity used to make a solar panel is generated by the panel within the first two years of operation, hence a solar panel will repay its greenhouse gas “debt” within this time.

Wind Power

Societies have taken advantage of wind power for thousands of years. The first known use was in 5000 BC when people used sails to navigate the Nile River. Persians had already been using windmills for 400 years by 900 AD in order to pump water and grind grain. Windmills may have even been developed in China before 1 AD, but the earliest written documentation comes from 1219. Cretans were using “literally hundreds of sail-rotor windmills [to] pump water for crops and livestock.”

Today, people are realizing that wind power “is one of the most promising new energy sources” that can serve as an alternative to fossil fuel-generated electricity. The cost of wind has dropped by 15% with each doubling of installed capacity worldwide, and capacity has doubled three times during the 1990s and 2000’s.As of 1999, global wind energy capacity topped 10,000 megawatts, which is approximately 16 billion kilowatt-hours of electricity. That’s enough to serve over 5 cities the size of Miami, according to the American Wind Energy Association. Five Miamis may not seem significant, but if we make the predicted strides in the near future, wind power could be one of our main sources of electricity.

Though wind energy is now more affordable, more available, and pollution-free, it does have some drawbacks. Wind power suffers from the same lack of energy density as direct solar radiation. The fact that it is a “very diffuse source” means that “large numbers of wind generators (and thus large land areas) are required to produce useful amounts of heat or electricity.” But wind turbines cannot be erected everywhere simply because many places are not windy enough for suitable power generation. When an appropriate place is found, building and maintaining a wind farm can be costly. It “is a highly capital-intensive technology.” If the interest rates charged for manufacturing equipment and constructing a plant are high, then a consumer will have to pay more for that energy. “One study found that if wind plants were financed on the same terms as gas plants, their cost would drop by nearly 40%.” Fortunately, the more facilities built, the cheaper wind energy is.

But there is increasing energy being put in finding many other alternative sources of power and making them viable, such as geothermal and wave energy and biomass!

Geothermal Energy

Energy from the Earth What could be more natural or plentiful? The source of geothermal power is the heat contained inside the Earth; heat so intense that it creates molten magma. There are a few different types of geothermal energy that can be tapped. “Some geothermal systems are formed when hot magma near the surface (1,500 to 10,000 meters deep) directly heats groundwater.” The heat generated from these hot spots flows outward toward the surface, manifesting as volcanoes, geysers, and hot springs . Naturally-occurring hot water and steam can be tapped by energy conversion technology to generate electricity or to produce hot water for direct use. “Other geothermal systems are formed even when no magma is nearby as magma heats rocks which in turn heat deeply-circulating groundwater.” In order to maximize the energy gleaned from these so-called “hot dry rocks,” geothermal facilities will often fracture the hot rocks and pump water into and from them in order to use the heated water to generate electricity.

The concentration of geothermal energy at any given location must be quite high in order to make heat extraction feasible, and not all geothermal sites are created equally. Regions that have well-developed geothermal systems are located in geologically active areas. These regions have continuous, concentrated heat flow to the surface. The western United States has the best geothermal regions in the country, while Iceland , New Zealand , the Philippines , and South America , are some of the more prominent global “hot spots.” In Iceland , geothermal energy, caused by the constant movement of geologic plates coupled with the volcanic nature of the island, is used to heat 95% of all homes.

Unfortunately even good geothermal areas are a non-renewable renewable. “The Geysers,” the world’s largest geothermal facility, is a working model on how not to approach a so-called “renewable” geothermal resource. Built in the 1950s on a steam field in Northern California , the facility was established on the apparent assumption that geothermal resources were infinite at that locatio. However, by the late 1980s, steam decline became noticeable and sustained. Depletion occurred because steam was being extracted faster than it could be naturally replaced. According to a report by Pacific Gas and Electric, “because of declining geothermal steam supplies, the Company’s geothermal units at The Geysers Power Plant are forecast to operate at reduced capacities.” In response, “plant operators and steam suppliers continually seek new operating strategies to maximize future power generation coupled with daily injection of millions of gallons of reclaimed municipal wastewater.” Even though improvements in efficiency and conservation are being implemented and in 1996 The Geysers was still producing enough electricity to supply the power demand of a city like San Francisco , it is projected that the steam field will be defunct in 50 years or so. To prevent this sort of thing from happening elsewhere, geothermal facilities can use a closed-loop system at all times, or the re-injection of water back into the system for constant steam generation, as PG&E is now implementing at The Geysers.

Despite the fact that geothermal energy is abundant renewable, and able to reduce our dependence on imported fuels, the fact remains that fields of sufficient quality to produce economic electricity are rare. In addition, many of those that are known are located in protected wilderness areas that environmentalists want to preserve. Unless research and technology join forces to “harvest” geothermal power through non-traditional means, such as deep-crustal drilling or the acquisition of heat from magma, the tapping of geothermal energy is limited to a handful of locations.

Environmental concerns also taint the issue of geothermal energy. Although no combustion occurs, some applications produce carbon dioxide and hydrogen sulfide emissions, require the cooling of as much as 100,000 gallons of water per megawatt per day, and dispose of toxic waste and dissolved solids.

Another type of geothermal energy being used commercially is Earth energy, extracted through heat pumps. Heat contained in shallow ground is used to directly heat or cool houses since the temperature inside the ground tends to stay at the yearly average. Therefore, in the winter the ground is warmer than the air and can be used to heat a building, and in the summer the ground is cooler than the air and can act as an air conditioner. Researchers know that “no active technology for home cooling is more efficient than the geothermal heat pump.” This technique reduces the reliance on other resources and can be utilized anywhere, resulting in significant environmental benefits and reduced energy costs.

Hydrothermal Reserves: Geothermal energy is found in many places on the earth. Its use contributes to the development of important third-world countries including the Philippines, Indonesia, Mexico, countries of Central and South America, and countries in eastern Africa and in eastern Europe. Italy, Iceland, New Zealand, Japan and France, along with the United States, are developed countries using geothermal energy.
There is a very large geothermal resource base in the U.S. and in the world, much of which can not yet be economically used. In fact, the resource base for the renewable energies- geothermal, solar, biomass and wind — is much larger than the total resource base in coal, oil, gas, and uranium (nuclear power).
There are also other problems that prevent us from taking full advantage of this form of energy. Even though there are geothermal resources throughout the world, our current technology is not sufficient or economical enough to warrant its widespread use. Funding for energy extraction that involves the penetration of magma is not available because we do not yet know how to prevent a high-temperature, high-pressure blowout. When heat pumps are considered, which tap local sources of heat and can help to reduce a family’s electricity bill by about $1 per day, the system is not economically viable. It “may have a payback period in excess of 5 years,” which will increase with decreased electricity rates “unless equipment and installation costs drop dramatically.” In addition, Earth energy is not “intense” enough to produce power for the electrical distribution grid; it is only sufficient to reduce the draw from the grid.

There are definite obstacles to be overcome before geothermal energy can be easily and economically harnessed for everyday, worldwide use. Case in point: “Construction of new domestic electricity-producing geothermal facilities in the Western United States during 1996 was limited to one site, due to the availability of cheap, plentiful natural-gas-fired electricity in the West.”