By Michael Thaler
The sun gives off an unimaginable amount of energy, yet it gives off no emissions and requires no combustion. The earths being positioned 93 million miles away, receives only an infinitesimal fraction of the sun's energy. Our planet enjoys 1,372 watts of sunlight per square meter, though only some of it is available for use, (30 percent is immediately reflected from clouds and ice) the remainder is driving weather by heating the atmosphere and oceans as well as fueling life throughout the biosphere.
According to US NREL (National Renewable Energy Lab), the energy from the sun that hits the earth everyday is enough to meet the energy needs of the earth's 6.6 billion inhabitants for 27 years. The amount of energy reaching the surface of earth is so vast that in one year it is about twice as much as will ever be obtained from all the earth's non-renewable resources of Coal, Oil, Natural Gas, and Uranium mines combined. It is estimated to be 35,000 times the amount of total energy used by humans.
Solar Energy is the cleanest, most abundant, renewable energy source available. Fortunately the U.S. has some of the richest solar resources available in the world.
Although early development of the Solar industry was overtaken by the development of more efficient oil and natural gas sources and technologies, the technologies that provide the sun's power go back to the classical Chinese, Greek, Romans, and pre Columbian American civilizations. By the 1st century A.D. the Romans were growing vegetal in greenhouses and storing solar heat using ceramic material. The Romans were the first to legislate solar rights. By the 1950s inexpensive fuels relegated solar energy to a hobbyist and experimental niche. Upon the oil embargo of 1973 solar energy gained relevance as the U.S. embarked on a future of vulnerability.
It has only been the last 10 years that Solar Energy has become efficient enough to account for a noticeable percentage of consumption in many developed countries. The increase in efficiency is due to technological advances and large scale deployment in both utility scale development and adoption by households. Much of the popularity has been driven by tax, finance, and procurement policies. Tax credits, Renewable Portfolio Standards and feed in tariffs make it an attractive investment. As the net cost of solar energy approaches the cost of general electricity, market intervention will be expected to decline.
The goal of solar energy technologies is to capture the energy (photons) and convert it into electricity at a reasonable cost. The most fundamental use of solar power is photosynthesis whereby plants use the sun's energy to convert carbon dioxide and water into vegetal matter. There are 2 main ways we convert solar energy to electricity (A) thermal solar power, which heats fluids and (B) solar photovoltaic power, which uses semiconductor materials to convert the suns energy into electrical current.
(A) Solar Thermal Power consists of Solar Hot Water Heat that uses hot water or air generated by the sun to provide hot water to a building. The process is made up of a series of thick panels containing water tubes or air baffles, under a blackened heat absorbing material. The heated water or air is piped to where it is to be used. Also Concentrating Solar Power, which is a utility scale system that concentrates the sun's rays to create high temperature water or other liquid which in turn runs turbines to generate electricity. There are three types of mirror configurations: Trough systems which are the most common using long parabolic shaped mirrors to concentrate the suns rays on a tube that runs down the center of the mirror, the tube is filled with a liquid that is heated to temperatures high enough to create steam, the trough rotates to the sun's direction. Dish-Engine systems use mirrors mounted on a large parabolic dish, creating a high concentration of rays which permit higher temperatures to be reached. Power Tower systems are fields of mirrors that direct the sun’s energy to a receiver which heats the molten salt to produce heat energy. Concentrating Solar Power has gained momentum due to comparatively low power generation costs and the advantage that large scale electricity can be generated in remote areas.
The utility bill for customers with solar water heaters is 50 to 80 percent lower than for consumers who have traditional electric water heaters (U.S. Dept. of Energy). Researchers have set a goal of cutting the cost of solar water heaters in half by using more advanced materials and collectors. Most of the solar hot water capacity is in China with 63.1% of installed world capacity (Europe 12.7%, the U.S. 1.8%-mostly swimming pools).
(B) The Photovoltaic effect was first observed by Edmund Bequerel in 1839, but not until the 1950s did high efficiency technology develop. Initially the uses were primarily for remote locations, spacecrafts, and satellites. Solar Photovoltaic which works by utilizing the sun's rays to create the flow of electrons between negatively and positively charged layers of semiconductor materials. Electrical contacts are attached to the solar cell generally through screen printing in order to collect and transport the electricity from the cell to an output contact. The elements of solar modules typically involve a backing plate called a substrate, the semi conductor layer, an antireflection coating in order to improve sunlight absorption, an aluminum frame box, and a glass cover to protect the entire module. Solar modules are being manufactured without solar cells; this is done by directly coating a substrate with a thin film of a semiconductor material. The solar modules are combined in a system. The important elements of a Solar Photovoltaic production include:
System Integration and Installation is where the modules are connected together Into an array, installed power is DC, direct current. A power inverter is usually used to convert the DC into the AC alternating current that can be used by the grid and most electronic devices. Photovoltaic power is for residential and commercial applications. Typically power can range from 2-10 KWH systems for residential projects and 10-100 KWH for commercial. Prices have fallen by about 5% per year and are already competitive with retail electricity prices in 10% of the developed world and are expected to grow to 50% by 2050.
The advantages of Solar Photovoltaic power is that:
The disadvantages are:
There has been a fast emergence of Thin Film solar technology changing the sector. Thin Film can be incorporated into the walls of buildings or the sunroof of cars or even paint. Crystalline silicon solar cells are 94% of solar energy production worldwide while Thin Film is 6%, likely to grow to 20% in the coming years. One of the advantages is not being subject to current shortages of silicon, though it does have its own supply issues of indium and telluride. Thin Film has lower production costs but with it comes 6-10% lower efficiency at present technology levels. Thin Film's future lies in its range of uses since it can be applied to different shapes and sizes.
Other experimental solar technologies are Solar Updrift towers, Solar Ponds (pools of salt water) and Solar Chemicals. A 2005 comparison of energy prices calculated for new plants coming on line in 2013 shows that Coal (.04), Natural Gas (.07), Wind, and Nuclear(.06), cost between 5 and 7 cents per kWh, while Solar costs about 22 cents, though costs of solar are expected to fall as technologies improve. At present levels of efficiency it would take about 10,000 square miles of solar panels, an area no bigger than Vermont, to satisfy all of the U.S. electricity needs.
Currently Solar Power provides less than 1% of the world's energy supplies. Total U.S. power generation capacity could increase by 30% per year but still account for only 1% of the total U.S. power generation by 2017, 2.4% by 2020, and 9% by 2025.According to PV News from 2001-2006 the annual rate of growth in the world for solar energy was 45.5%, mostly driven by Germany and Japan. The IEA estimates from 2001-2030 new power generation capacity of 4,700GW will be built worldwide (9,400 medium sized 500 MW power plants); this will be a four trillion dollar investment. IEA reports one third of the new capacity will be built in developing Asia. It must be stressed that over one third of current total electricity capacity in the OECD nations will need to be replaced because of aging facilities. The IEA forecasts that the OECD countries will require more than 2,000 GW of new capacity (4,000 medium sized 500 MW plants). This will require collaboration from government and the public sector, this is reflected by the sums of money venture capital has invested Into clean technology sectors, in 2008 alone:
When you generate solar electricity locally you don't need transmission lines and you save all the associated inefficiency. When you install a 3KWH solar system, you are offsetting the need for that much power from the utility company and about 9 KWH of total power consumption because of inefficiencies, as well as the associated carbon footprint. When one KWH of solar power falls onto a one square meter surface, one can expect to capture about 6 KWH of total energy. 5 square meters is enough to completely replace a typical (U.S.) monthly power bill.
When one considers the diverse applications Solar Power provides, it is sensible to conclude that solar will provide profound affects on the people of impoverished nations and villages. Solar has the potential to impact the world in many positive ways where other initiatives have failed. Solar has the ability to balance the impact of initiatives the developed countries are thrusting upon the developing countries due to climate change. The Solar Power applications may seem obvious such as remote off grid locations, military, microwave stations, Television radio towers, remote sensors as in pipelines, wellheads, bridges, water pumps, buoys, light houses, warning lights, road lights, landscape lighting providing safety, lighting remote dwellings, space heating and cooling, potable water by distillation and disinfection, hot water, thermal energy for cooking, high temperature process heat for industrial purposes, refrigeration, and electrical generation for uses that will behold in the future.
Solar Energy will impact education through out the developing world by providing more time for reading, impacting the world in unknown ways. Solar could provide clean water, power for accessible water pumps which could reduce the number children that die each year from diarrhea now 11 million, or the 1.1 billion who presently lack access to clean water. There are 4 billion cases of diarrhea each year in the world. Solar can provide power for more efficient irrigation leading to healthier diets, reducing the number of children that die each year from hunger now 6 million. Solar can provide refrigeration which could store immunizations for diseases such as Malaria which kill more than 1 million each year, leading to improvements in medical and public health services. Solar can provide lighting in remote areas that will provide safety, as well as provide accessibility. Solar can provide power in remote areas resulting in the ability for people to create goods for trade they once never were able to, possibly creating a more sustainable local economy.
In order for Solar to progress and succeed in meeting the challenges and expectations, governments, industry, city planners, and policy developers will need to coordinate technologies, policies, and finance. This will be a great task that will require educating people of all ages in order to build momentum to achieve the desired results. The continued growth of Solar is inevitable as fossil fuels become more depleted, and as public and government policies continue to be more fossil fuel averse. The roots of momentum appear to be taking hold, evident by recent reports such as the world's second largest solar plant is being built in Florida. Lauren Engineers& Constructors have contracted with Florida Power and Light for a new 75 MW CSP plant. More locally, Jersey Central Power and Light expects to help support the phase in of 42MW of Solar generating capacity over the next 3 years to meet their renewable portfolio standard thru 2012, enough to power 32,000 homes.
Why Solar Works Where It Snows
I've been hearing objections for years against solar energy in the Northeast.
These objections come on the heels of bad experiences many homeowners had under the Carter years when solar domestic hot water systems were installed at a breakneck pace by companies of varying degrees of reputability, with even more varying degrees of workmanship and integrity. These homeowners instilled the distrust and malaise to their children, who grew up in homes with these sometimes completely broken systems. Many of these homeowners were completely abandoned and in the dark after the installation was complete, with no idea if their system was working or not. It was the Wild, Wild West days of solar.
Solar is back thanks to creative financing options, great rebate and tax credits, and the international support of top-notch manufacturing and material science. In the Northeast, where fuel oil prices are poised to rise significantly again, where electricity rates are some of the highest in the nation and rising rapidly, there is no better time to better examine these objections than now.
1. It's too expensive.
The cost of inaction is even more expensive, but much harder to quantify in a simple way. However, the good news is that due to the rising costs of fuel oil and electricity, the falling costs of solar equipment, and the increased level of employee training and certification for installers are all contributing to making solar much more cost effective.
Even further, financing programs like power purchase agreements (PPAs) and residential solar electricity programs are making solar a low-cost, low-to-no-risk proposition.
2. It's not reliable.
Sure as the sun comes up every morning, solar energy is there working for you. The question of reliability is really a question of "how do I know if it is actually working?" Just think, would you drive a car with no fuel gage or spedometer? The great news is many companies are offering easy-to-use and understand monitoring equipment that can help you see real time data about the performance of either your solar electric or solar hot water system. You'll know immediately if something is wrong. In many cases, systems can automatically notify your installer of a problem before you even know. Monitoring technology has come a long way since the 1970's to help people have a little peace of mind.
3. No one will be around to support it.
Many companies providing solar energy solutions have or are building full support and service centers to help customers understand problems with their systems or just to be there when confusion arises. Installers are improving their websites; taking notes from the successes in the IT industry and providing online databases of frequently asked questions, online support forums, user forums, and much more.
Many companies, too, are at the point where they have a significant history behind them- 10, 20, even 30 years of combined experience in installation, program management, and industry experitise. Do your homework on your installer if you are worried about whether or not they will be there for you in 5 years or 20 years.
4. We get too much snow- it doesn't work in the winter.
Many people in the Northeast don't realize that we have a wonderful solar resource available. In fact, Germany, arguably the world leader in acceptance and deployment of photovoltaics, receives less average solar insolation anually than the Northeast.
So while it snows in the winter, just remember- after the snow falls, the sun comes out and the sky is clearer than on those hazy July days. Soon the snow will be sliding right off your panels and you'll be back to producing clean, renewable power. The average roof pitch of most Northeast homes is quite ideal to solar installation, too, and will encourage snow to shed from panels.
Examine your objections. Make the right choice.
There are many more reasons why people object to solar power, but as the industry and its people supporting it continue to provide better service, offer better financial deals, and continue to exceed the expectations of the doubting public we hope you will join us a become another gleaming solar roof from space and a proud part of our clean energy future.
Carbon Finance, Sonia Labatt and Rodney R. White
Profiting From Clean Energy, Richard Asplund
The Wall Street Journal, Tuesday January 13, 2009
National Geographic April 2009
Solar Power Your Home for Dummies, Rik DeGunther
Solar Power; Lighting up The Future, Juergen-H. Lange
In 2011 TLR Energy begins distributing a solar-powered portable Medi-fridge to remote locations without access to electricity in South Africa... more