What is a Solar Power Tower? – Types, Operation, Cost, and Applications

Mounting challenges of climate change and worldwide energy shortage has made solar power one of the world’s most dynamic and reliable sources of energy. 

With this global trend towards renewable solar energy, it is no surprise that solar tower power plants are becoming more widespread. Solar-powered towers harness the Sun’s heat to produce electricity via a solar radiation technology called solar concentrators. 

We are sure you are curious to know more about solar towers and how they work. So, let’s dive in!

What is a Solar Tower Power Plant?

Solar tower power plants are large-scale solar energy generation setups that use mirrors called heliostats to capture sunlight. Since solar towers rely entirely on sunlight, they are one of the most sustainable and greenest options for energy generation. 

However, you may be thinking, can they work in the absence of sunlight? The answer is yes! Since solar towers contain a heat-storing medium (water or molten salts), they can continue working without sunlight.

Now, let’s look at how solar towers work!

How Do Solar Tower Power Plants Operate?

Firstly, you should know that solar towers are a part of solar power plants. These solar towers are basically central towers that receive the captured sunlight from the surrounding mirrors. 

A solar tower stands in the middle of a sizable arrangement of mirrors. These mirrors can be curved or flat. However, most solar tower power plants use flat mirrors due to their cost efficiency. These mirrors catch the directly falling sunlight as they follow the sun’s rays. 

Afterward, the captured sunlight is reflected or redirected to the solar tower. Many of these mirrors concentrate a significant quantity of solar radiation onto the receiver, a small area of the tower where water is heated. 

Older solar towers used water as a direct heat-transferring medium. However, newer and more advanced solar towers use molten salts with significantly higher efficiency to heat water. Water plays a significant role in energy generation; once heated, it generates steam which turns the turbine. Consequently, this process generates electricity.

Does that sound quite technical? Well, to put it simply, here is how solar tower plants work in a nutshell!

• Mirrors capture sunlight.
• The sunlight is directed to the solar tower.
• The sunlight is used to heat the stored fluid (water or liquid sodium).
• Steam is generated from heating the fluid.
• The steam moves the turbine.
• The rotation of the turbine produces electricity.

Installing a solar tower is undoubtedly a wise decision. But how much does it cost? Let us find out!

Cost of Solar Tower Power Plants

There is no definite cost for solar tower power plants as the overall cost of the setup greatly depends on its components.

• Type of Mirror used: Solar tower power plants may use flat mirrors or curved mirrors. Although both mirrors have equal efficiency, most systems use flat mirrors. This is because the flat mirror is comparatively cheaper than curved mirrors.

• Type of Heating Fluid: As we mentioned earlier, older solar towers use water as the heating fluid. However, it is not cost-efficient as a stable flow of a considerable amount of water is required to operate the tower. In comparison, modern solar towers use liquid sodium, which has higher efficiency. 

• Installation Cost: Mounting structures and other necessities for installing the solar tower can affect the overall cost of the system.

What are the Benefits of Solar Tower Power Plants?

The primary benefit of solar towers is that they do not use fossil fuels for operation. The entire process of energy generation is reliant on sunlight. Therefore, it produces no emissions. 

Moreover, newer solar towers that use molten salts for energy storage can continue producing electricity even without sunlight. Hence, solar towers can work 24/7 without any interruptions due to the weather, making them a very reliable energy source.

What are the Drawbacks of Solar Towers?

Solar tower power plants are indeed highly beneficial and a green source of energy generation. However, they still have certain drawbacks as well.

• Solar towers need a constant water supply to generate steam that can turn the turbine to produce electricity.
• The overall temperature around the solar tower can reach up to 550 °C, which is harmful to wildlife.
• The components of the solar tower, such as heliostats, can produce harmful byproducts during manufacturing.

Solar towers are still reasonably new, and researchers and manufacturers are constantly working to improve them to reduce their drawbacks. Therefore, they are certainly worthwhile for the future.

Applications of Solar Tower Power Plants

Solar tower power plants are large-scale setups, making them perfectly suitable for commercial applications. Among the most notable solar tower plants, one of the biggest solar towers produces 650 GWh of energy per year. 

In addition to commercial applications, there have been numerous attempts to use them for other innovative applications as well. 

Using solar energy in both domestic and commercial spaces can significantly reduce yearly carbon emissions. 

In addition, systems generating solar energy, like the solar tower power plant, are sustainable and comparatively cheaper than conventional Photovoltaic systems. 

Conclusion

Solar power towers are highly reliable. Comparatively, PV systems fall slightly behind in this regard as they rely highly on direct sunlight. 

On the other hand, solar towers can generate electricity regardless of the presence of sunlight. Therefore, they are highly beneficial and something to look forward to for a better future.

FAQs

Q. Can solar tower power plants work without sunlight?

Solar towers generally require a certain amount of sunlight for heat generation. However, unlike Photovoltaic systems, they do not require constant sunlight exposure. 

Instead, the captured heat from the sunlight is stored in the solar tower. Therefore, when there is a lack of sunlight, the solar tower can still continue operating and generating electricity.

Q. What is the cost of solar towers?

The price of a solar tower varies according to the type of components used and how it has been installed. Therefore, it has no fixed price. 

Q. How much space is necessary for installing a solar tower?

Generally, you will need an open space of around 150 to 320 hectares to install a solar tower and the mirrors necessary for the operation.