Most people agree that excessive greenhouse gases are a problem that must be addressed. Industries that rely on fossil fuels are especially highlighted as needing to reduce emissions and businesses are looking for methods to meet government targets without compromising their own agendas.
One option in the battle to decarbonise is the replacement of open cycle gas turbines to a combined cycle. Although not totally solving the issue, this technology has the ability to reduce greenhouse gas emissions while providing the same or higher power output.
Let’s find out more…
Why is decarbonisation important?
Greenhouse gases, such as CO2, trap heat in the Earth’s atmosphere, gradually raising the temperature of the planet. Global warming and climate change are becoming ever more concerning issues and so governments around the world are taking steps to reduce greenhouse gas emissions.
In 2020, the Energy White Paper3 (EWP) set the goal to reduce the UK’s greenhouse gas emissions to net zero by 2050. The burning of fossil fuels is especially highlighted as a practice that releases vast quantities of greenhouse gases. Consequently, businesses that rely on gas and coal are asked to find ways to reduce their emissions or potentially face penalties.
Gas turbine power plants must play their part in the global effort to reduce greenhouse gas emissions and combined cycle power plants could be a good place to start.
What is a combined cycle power plant?
A combined cycle power plant utilises a gas powered turbine but ‘combines’ it with a secondary steam turbine. The waste heat from the gas turbine is used to produce steam which drives the second turbine, generating up to 50% more electricity from the same amount of fuel.
The electricity generated from the second turbine is essentially emissions-free, helping power plants and the world as a whole meet emissions targets.
Combined cycle power plants: real world applications
While open cycle power plants are currently more common, more and more companies are considering combined cycle as they pledge to reduce emissions.
In the Gulf of Mexico, Shell’s Appomattox production platform is one of the world’s first offshore sites to incorporate a combined cycle power plant. It features:
• four 27MW aeroderivative gas turbine-driven generator sets
• a 40MW steam turbine generator
and its total output is ~150 MW.
Each of the gas turbines has an OTSG (once through a heat recovery steam generator) which recovers heat from the exhaust steam. In addition to this, supplementary firing uses the hot exhaust gas as an oxygen source, firing it directly into the pressurised superheater to increase heat flow by up to 600°F. In this way, steam production is extremely efficient.
Since it began operations, the power plant has kept its NOx emissions well below target while also reducing
carbon emissions and fuel consumption. The site is deemed a huge success and shows the potential combined cycle power plants have to make an enormous difference as we strive to meet emissions targets without compromising productivity.
Get in touch
At Rochem, we’ve been working with gas turbine power plants for over 40 years. Recent advancements in the sector are extremely exciting and we believe combined cycle power plants could make a real, valuable difference to our customers and the planet.
However, while the possibilities of combined cycle technology are promising, you may not be ready to make such drastic changes at your site just yet. Our speciality is equipment and
chemicals for gas turbine compressor cleaning, which already helps thousands of power plants reduce greenhouse gas emissions while improving productivity and reliability.
If you’re interested in how our products could help you meet emissions targets without the significant commitment and expense of changing your site to a combined cycle,
get in touch. Our friendly, expert team will be happy to answer all your questions.