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Combined cycle

Combined cycle

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The most technologically advanced thermal power stations work in combined-cycle; natural gas is used as a fuel for generating electricity, replacing other more pollutant fossil fuels such as coal or diesel. Combined-cycle plants have many advantages in environmental and efficiency terms: for example, they produce more electricity from a given amount of fuel.


More and more energy is being consumed all the time by new domestic appliances, computers, microwaves, air-conditioning, etc. Our changing lifestyle means that every year the demand for electricity increases and we want to see those energy needs met.

Combined-cycle offers a real solution, since it allows sustainable development for our society by producing that essential electricity at a lower ecological cost, considerably reducing emissions of the gases that cause the greenhouse effect as compared with the fuels used up till now, such as coal or diesel.

Reduction in emissions:

  • 50% of CO2 emissions
  • 100% of SO2 emissions
  • 80of NOx emissions


A combined-cycle power station using natural gas needs less space than a conventional thermal power station, and therefore the visual impact is reduced.

  • Power station housing the gas and steam turbines used to produce electricity.
  • Electricity substation for grid connection.
  • The power station requires water for cooling. A water inlet takes in as much as is necessary and after use it is returned intact to the sea at a different point. For more information on this subject, go to:


The station takes only 30 months to build. It is built like a Meccano set: the plant is made up of different modules, which are assembled one after another.


Inside the plant, the combined-cycle produces electricity twice over: first by burning natural gas in the gas turbine and then using steam, in the steam turbine. This is the reason why this sort of plant has such high efficiency rates.

  • Natural Gas

    In the natural gas cycle, combustion of the gas produces gases at high temperatures that turn the blades of the gas turbine. Because this turbine is connected to the power generator, the rotation produces electricity.

  • Steam

    The gases generated in the gas cycle are expelled at 600º C and are used to heat water in the recovery boiler and produce steam. This is channelled to the turbine so that it moves the blades, again generating electricity.

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