Concentrated solar power (CSP) systems use focal material, such as lenses or mirrors, and a tracking system to focus sunlight onto a small area to produce intense heat. The concentrated light is then used to create heat as a source for conventional power.
CSP is not a new technology. In the 1860s, French inventor Augustin Mouchot created a solar-powered engine that converting solar energy into mechanical work via steam power. Mouchot believed that coal, the fuel of the industrial revolution, was in limited supply and would eventually be unavailable. Mouchot and his engine were victims of the same tribulations of today, however. More efficient delivery and use of coal in the 1870s allowed prices to drop, and Mouchot engines became economically unviable.
CSP is again being explored as a reasonable option for clean energy, with CSP photovoltaic (PV) panels installed in both home and industrial applications.
The interest in CSP is a result of the high cost of PV panels. Concentrating solar is simplicity in design. It employs reflective material, such as mirrors, polished metals, or even fabrics such as Mylar, deployed in a radius around a central tower. The reflective materials are remotely controlled to track the sun during the day.
The central tower on which the reflective materials are mounted is filled with the material to be heated, which could be water, oil, salt, or other substances that can store light energy as heat. As the sun rises, it heats the water to more than 1000°F. The heated material creates steam and turns a turbine to power a generator, which produces electricity. The heated material will be at relative low temperature during the beginning of the day and near its hottest temperature by the end of the day. The system should theoretically store enough heat energy to continue to produce steam, and therefore, electricity day and night.
Concentrating solar power of this type is not a 24-hour-a-day solution, however. Although CSP plants are usually constructed in sunny areas of the world, even the great deserts sometimes have more than a day of cloud cover. Sandstorms, dust, birds, inclement weather, and intermittent sunlight all contribute to inefficiencies in this type of system. Some of these power stations are used to produce intermittent energy when the sun is available. When a constant power solution is required, natural gas or oil is usually substituted to maintain a constant temperature.
With many variations of concentrated solar power available, you will see more CSP solutions in the future.
CSP is not a new technology. In the 1860s, French inventor Augustin Mouchot created a solar-powered engine that converting solar energy into mechanical work via steam power. Mouchot believed that coal, the fuel of the industrial revolution, was in limited supply and would eventually be unavailable. Mouchot and his engine were victims of the same tribulations of today, however. More efficient delivery and use of coal in the 1870s allowed prices to drop, and Mouchot engines became economically unviable.
CSP is again being explored as a reasonable option for clean energy, with CSP photovoltaic (PV) panels installed in both home and industrial applications.
CSP with Parabolic Mirrors
Concentrating solar power with parabolic mirrors is used for industrial, commercial, and home applications.
The interest in CSP is a result of the high cost of PV panels. Concentrating solar is simplicity in design. It employs reflective material, such as mirrors, polished metals, or even fabrics such as Mylar, deployed in a radius around a central tower. The reflective materials are remotely controlled to track the sun during the day.
The central tower on which the reflective materials are mounted is filled with the material to be heated, which could be water, oil, salt, or other substances that can store light energy as heat. As the sun rises, it heats the water to more than 1000°F. The heated material creates steam and turns a turbine to power a generator, which produces electricity. The heated material will be at relative low temperature during the beginning of the day and near its hottest temperature by the end of the day. The system should theoretically store enough heat energy to continue to produce steam, and therefore, electricity day and night.
Concentrating solar power of this type is not a 24-hour-a-day solution, however. Although CSP plants are usually constructed in sunny areas of the world, even the great deserts sometimes have more than a day of cloud cover. Sandstorms, dust, birds, inclement weather, and intermittent sunlight all contribute to inefficiencies in this type of system. Some of these power stations are used to produce intermittent energy when the sun is available. When a constant power solution is required, natural gas or oil is usually substituted to maintain a constant temperature.
With many variations of concentrated solar power available, you will see more CSP solutions in the future.
Stirling Engine
A variation on concentrated solar power is the Stirling engine. Like CSP with parabolic, this is concentrated solar power; however, instead of focusing the sunlight on a central tower, the sunlight is focused on an “engine” to create mechanical work and then electricity. This type of energy production has many benefits but one challenge that separates it from other forms of concentrated solar energy: The Stirling engine produces a loud sound similar to that of an internal combustion engine, which prohibits its use inside the home.
The Stirling engine functions on the principle of a differentiation in temperature. You may be familiar with the Stirling engine from a small engine used in high school science class. A teacher may have held this engine on his or her hand, or over a cup of hot water, and the temperature variation would turn the wheel on top. This is similar to what occurs with the larger solar version of the engine. The concentrator focuses the sunlight on the receiver, or the Stirling engine, and produces usable energy. This system is then tied into the grid for some type of immediate power usage.