Working of CSP - Dish Engine.

Continuing in our CSP series, let’s understand how dish antenna works.

Before going to parabolic trough, let’s understand the principle of CSP.

The receiver receives heat from sun light. This heat is gathered in oil or other heat medium which further converts water into steam. This steam is used to run steam turbine which produces electricity.

Source : solareis.anl.gov

The working of dish engine is slightly different from Parabolic Trough and Power Tower. Parabolic Trough and Power Tower used steam turbine to produce electricity whereas Dish Engine uses external combustion engine to produce electricity. The receiver situated at the focal point of the dish has external combustion engine. It has hydrogen or helium gas filled in piston cylinders. As concentrated sunlight falls on the receiver, it heats the gas in the tubes to very high temperatures, which causes hot gas to expand inside the piston cylinders. The expanding gas drives the pistons. The pistons turn a crankshaft, which drives an electric generator.

Here are some images of Dish Engine CSP. 

Working of CSP - Power Tower

Continuing in our CSP series, we are going to understand how power tower works.

Before going to parabolic trough, let’s understand the principle of CSP.

The receiver receives heat from sun light. This heat is gathered in oil or other heat medium which further converts water into steam. This steam is used to run steam turbine which produces electricity.

Source : solareis.anl.gov

As shown in the figure the reflectors which are known as heliostats reflects and focuses sun light to a tower. This tower is a heat receiver. These heliostats track sun all the day so that they can focus maximum sun light. There is a fluid in this tower such as molten salt. This fluid heats up to 565 °C. The fluid then converts water into steam. This steam is used to run steam turbine to produce electricity.

Molten salt can retain heat for long time. So it can be used to make steam when there is no sunlight or during night. That means this is advantage of CSP over photovoltaic cell which cannot produce electricity when there is no sunlight.

This system is cheaper than photovoltaic cell. And it has low maintenance too!

Here are some images of this system.

Working of CSP - Parabolic Trough

As concentrating solar power technology is developing day by day, here is an explanation how parabolic trough works.

Before going to parabolic trough, let’s understand the principle of CSP.

The receiver receives heat from sun light. This heat is gathered in oil or other heat medium which further converts water into steam. This steam is used to run steam turbine which produces electricity.

As you can see in the image the parabolic concentrator concentrates heat into the pipe which is filled with oil. These concentrators are made of mirrors. Concentrator tracks sun all the day so that they can get maximum solar energy. The oil in pipes heats up to 395°C. This oil converts water into steam. This steam is used to run steam turbine which will produce electricity.

This system is cheaper than conventional solar system which uses photovoltaic cell which is costly. This system has very less working parts so the maintenance cost is very low. 

Here are some images of parabolic trough. 

Desertec - Concentrating Solar Power From Deserts.

Our world is going to face energy crisis. Scientists are trying to find new eco-friendly and affordable energy sources. 70% of our electricity needs are being fulfilled by natural gas, petroleum, coal and nuclear power. But these energies are not renewable and are not eco-friendly too.

Desertec foundation is an organization which wants to generate renewable energy on nonprofit basis. They are focusing on solar energy which is raining in deserts! Deserts gets most amount of solar energy in the world. Deserts cover about 2,98,00,000 square kilometers of earth that means fifth part of earth is desert. If we combine 1 year energy of all the fossil fuels, then it would be equal to only 5.7 hours of solar energy in deserts. Energy in 1 square kilometer for 1 year in desert would be equal to 15,00,000 barrel of petroleum! World’s total energy needs can be fulfilled by utilizing only 1% area of deserts. Keeping this in mind, Desertec foundation is focusing on making energy from this.



They are using Concentrated Solar Power technology to generate electricity. This technology is cheaper than solar cell (photovoltaic cell) and has more efficiency too! This technology uses solar heat to run the steam turbine which ultimately converts it into electricity. Because of this, the technology is also known as Solar Thermal Energy. This technology has efficiency near to 30% which is almost double than photovoltaic cell (efficiency 15% - 20%).

The types of CSP (Concentrated Solar Power) are as under.

1. Parabolic Trough. 
2. Power Tower. 
3. Dish Engine. 
4. Linear Fresnel Reflectors.

All these types are different but they use same principle. Concentrating Solar Power (CSP) is electricity generated from mirrors to focus sunlight onto a receiver that captures the sun’s energy and converts it into heat. This heat can run a standard turbine generator or engine. These systems range from remote power systems which are as small as a few kilowatts and up to grid-connected power plants of 100’s of megawatts (MW). CSP systems work best in bright, sunny locations like the Southwest which has most deserts like areas. Because of the economies of scale and cost of operation and maintenance, CSP technology works best in large power plants.

Here are some images of CSP.

Parabolic Trough.

Power Tower.

Dish Engine.

Linear Fresnel Reflectors