Solar radiation is an amazing, endless energy source for use through a variety of technologies. Believe it or not, the sun produces enough energy each and every hour to power the world for one year! Even though we are accustomed to smaller applications of this energy, such as a solar-powered calculator, a solar power panel to heat water for a home, or perhaps even a solar power vehicle; it's also possible to provide solar energy on a large scale, such as the energy generated by a solar power plant. In this situation, the solar power plant could behave like any other electricity utility and supply energy to consumers within a sensible distance from the plant. There are two fundamental forms of utility scale solar power technology:
Concentrating Solar Power (CSP) Technologies
Concentrating solar power technology works about the way its name sounds - it yields power through the concentration of the sun's rays, usually with small mirrors. These mirrors are then utilized to heat fluids (and occasionally solids) that aid in the production of steam to power turbines and other such power-producers. Several subtypes of this sort of technology are available. In a trough system, U-shaped focusing mirrors include oil pipes in which the sunlight heats the oil, which is utilized to boil the water that creates the steam that powers the machinery. In a power tower system, flat mirrors are utilized to follow the sun's position through the sky and concentrate rays on the receiver on top of a large tower. The sun heats up a fluid (typically molten salt) that then produces the steam required to produce power. Molten salt stores heat and thus, can be used on cloudy days and well after the sun has set. And lastly, in a dish or engine system, mirrored dishes follow the sun throughout the day, capturing the light and concentrating it on to a receiver that is part of a combustion engine. The combustion engine contains tubes of hydrogen gas or helium that is heated by the sun's rays, causing the gas to expand and power pistons that power an electric generator.
Photovoltaic (PV) Technologies
PV systems are one of the most commonly encountered solar power technologies. As opposed to converting sunlight into heat that then yields power, these systems transform the sunlight directly to energy. Solar cells, only one type of Photovoltaic technology, are made from semiconductor materials that cause electrons to flow through the material and generate electrical energy when heated by the sun's rays. Unfortunately, these cells are far too small for utility purposes. However, a solar array brings together modules of around 40 cells into arrays which may be meters long on each side. Hundreds of arrays can be put together to form one large system that will generate adequate power for a utility. In a concentrated PV system, sunlight is targeted on cells using a lens or mirror. These provide a low-cost and high efficiency choice that can be scaled up rapidly, all factors which make them a great candidate for use on a utility scale.
Concentrating Solar Power (CSP) Technologies
Concentrating solar power technology works about the way its name sounds - it yields power through the concentration of the sun's rays, usually with small mirrors. These mirrors are then utilized to heat fluids (and occasionally solids) that aid in the production of steam to power turbines and other such power-producers. Several subtypes of this sort of technology are available. In a trough system, U-shaped focusing mirrors include oil pipes in which the sunlight heats the oil, which is utilized to boil the water that creates the steam that powers the machinery. In a power tower system, flat mirrors are utilized to follow the sun's position through the sky and concentrate rays on the receiver on top of a large tower. The sun heats up a fluid (typically molten salt) that then produces the steam required to produce power. Molten salt stores heat and thus, can be used on cloudy days and well after the sun has set. And lastly, in a dish or engine system, mirrored dishes follow the sun throughout the day, capturing the light and concentrating it on to a receiver that is part of a combustion engine. The combustion engine contains tubes of hydrogen gas or helium that is heated by the sun's rays, causing the gas to expand and power pistons that power an electric generator.
Photovoltaic (PV) Technologies
PV systems are one of the most commonly encountered solar power technologies. As opposed to converting sunlight into heat that then yields power, these systems transform the sunlight directly to energy. Solar cells, only one type of Photovoltaic technology, are made from semiconductor materials that cause electrons to flow through the material and generate electrical energy when heated by the sun's rays. Unfortunately, these cells are far too small for utility purposes. However, a solar array brings together modules of around 40 cells into arrays which may be meters long on each side. Hundreds of arrays can be put together to form one large system that will generate adequate power for a utility. In a concentrated PV system, sunlight is targeted on cells using a lens or mirror. These provide a low-cost and high efficiency choice that can be scaled up rapidly, all factors which make them a great candidate for use on a utility scale.
