Steam Turbine efficiency increase as part of decarbonization initiative in power plants

In the course of global efforts to reduce decarbonization and expand renewable energies, the gradual reduction and increase in efficiency of existing fossil-fired plants will also be necessary over the next few years and decades. These CO2 reduction measures can be very diverse, from the capture of CO2 in the CCS process or the combustibility of hydrogen in gas turbines, to the consistent construction of combined cycle power plants with the highest levels of efficiency.

Here are some thoughts on optimizing the steam content in CCPP power plants.

To maintain a steam turbine, you ought to keep the organs of the machine. These are components of the generator which play a very important role in generating electricity. Should the parts work properly, only then will the device generate enough power to provide electricity? Therefore, to understand how to increase the efficiency of a generator, you should understand why the components are important first:?

Condensers?

A condenser is a place where real action happens. It looks like a tube shell that has a heat exchanger and an exhaust that generate steam. The steam inside the condenser changes the gaseous form into liquid form. This is brought down below the atmospheric pressure level, after which there is a short jest of cold water.

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Feedwater heating?

Feedwater is an important part of steam turbine generator efficiency. A major part of this component is to preheat the feedwater which makes irreversible changes to it which helps with steam generation. This improves the thermodynamic efficiency of the power plant generator. This also reduces the cost of operation and reduces the risk of thermal shock from the boiler.?

How to improve the efficiency of steam turbine power generation??

Feedwater temperature?

The temperature of the feedwater heater is something to take note of. Should the temperature be less than the amicable, there can be some damage to the machines, thus decreasing efficiency. This is because the heat transfer is compromised and thus is not functioning at its optimum.?

Exhaust pressure?

The exhaust system can help you immensely if you use it the right way. But it constitutes insertion losses if they are not placed in a way that maximizes the cross-sectional area allowing more steam to pass. The radius and the difference between the bends should be broad; otherwise, there would not be enough space for steam to pass, reducing the efficiency.

Condensate subcooling

The point of a condenser is to change the steam’s gaseous form into liquid form. The steam passes through the condenser to cool down. One way to increase the efficiency is to reuse the water in the plant again. If the temperature is below the saturation level, then the output of the turbine will decrease. Hence you can also increase the temperature to increase efficiency by generating more steam. The duty of the feedwater heater is increased by the sub-cooling process, which increases the extraction flow to the heater, thus increasing the heart rate.?

Superheat?

The superheating area of the steam turbine functions on the Ranke cycle, which is increased by making the temperature is at its peak. The beauty of it is you can do this without increasing the temperature of the boiler pressure. Introducing a superheater system can significantly help the efficiency of a power plant generator.?

Reheating?

This is another way of generating more power. Ideally, the efficiency of a steam turbine is around 80%-90%. But if you manage to introduce a reheater, then the steam temperature will increase and thus increase the output.

For further details on the Siemens Energy Portfolio and specifically the portfolio and modernization potential of steam turbines check out the homepage:

https://www.siemens-energy.com/global/en/home/products-services/product/utility-steam-turbines.html

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