Solar power plant
Posted by Solar energy guru | Filed under Solar power systems
A solar power plant is not the best way to harness solar energy for everyday use but as technology increases, they may be the wave of the future. The solar collectors take up too much space in comparison to the amount of electricity generated to make them feasible as a complete replacement for traditional power plants. However, a solar power plant can provide a supplemental source of clean, renewable energy.
There are many more solar power plants in Europe than there are in the United States but that may change in the near future. As more state and federal legislation is passed to mandate decreased reliance on fossil fuels, many areas are studying the possibilities for harnessing solar power efficiently. California is one state that is requiring utilities to produce at least 20% of their power from renewable sources within the next two years.
Pacific Gas and Electric, the main energy supplier in California, has recently teamed up with BrightSource Energy to create the world’s biggest solar power deal. They will be utilizing the blazing sun over the Mojave Desert to build three new solar power plants which will produce 500 megawatts of clean electricity. Additional plants are also a possibility in the deal which may total $3 billion dollars in the end.
BrightSource has developed a more efficient method of using solar thermal energy which they call Distributed Power Tower technology. The plants will use thousands of tiny, movable mirrors known as heliostats to focus the sunlight upon a water boiler. The concentrated solar energy heats the water up to over 1,000 degrees. This results in steam which then drives a turbine, producing electricity.
The new Mojave Desert solar power plants will have clusters of these towers, called solar fields, and each tower can produce 20 megawatts of electricity. BrightSource is predicting that because of the large scale, production costs will be driven down and they will be able to price competitively with fossil fuel energy production. Of course, the added reliability of solar energy will help reduce the cost of production long term.
A solar power plant that produces larger amounts of energy utilize concentrating solar power (CSP) systems of some sort. CSP systems use mirrors or lenses along with tracking systems to gather a large amount of sunlight and concentrate it. The concentrated light is used as a heat source for the power plant. The three most common types of CSPs are the solar trough, parabolic dish and solar power tower. Each type of system use the concentrated light to heat fluid that is then used for power generation or storage.
A solar trough uses a linear parabolic reflector to concentrate and focus the light onto a receiver. The reflector tracks along a single axis to follow the sun during throughout the day. These types of systems are the best ones for ground solar collection systems.
A parabolic dish system uses a stand-alone parabolic reflector that concentrates the light onto a receiver as well but at a different position. This type of reflector tracks the sun along two axes, giving it the highest efficiency level of all the current CSP systems.
A solar power tower uses heliostats to concentrate the light toward a receiver that is set on top of a tower. Solar power towers offer higher efficiency and much better energy storage capabilities than the solar trough technologies.
There is work being done now to create a space solar power plant. The space solar power plant, when out of the concept stage, could deliver usable power close to 100% of the time. The idea is to use a huge solar array in orbit. This energy would be transferred to the earth by microwave radiation and then distributed. This type of solar power plant has the potential to solve most of the world’s energy problems if it can be fully developed.