Gas turbine power plant

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The Hamburg-Moorburg gas turbine power plant (demolished in 2009)

A gas turbine power plant is a power plant for generating electricity that is operated with petroleum products or with fuel gases such as natural gas . These fuels are used to operate gas turbines which in turn drive coupled generators .

Properties of gas turbines that make their use for power generation interesting are their high power density and their ability to start quickly. For the latter reason, it is used to cover short-term peak loads . Gas turbine power plants that have been built have an output of up to 340  MW per unit . Such a turbine, roughly the size of a truck trailer, can supply a city with around 380,000 inhabitants with electricity.

With conventionally produced natural gas, the greenhouse gas emissions from gas turbine power plants are between 570 and 750 g CO 2 -eq / kWh; the median is 670 g CO 2 -eq / kWh.

description

Gas turbine for natural gas operation ( heavy duty )

Gas power plants are characterized by relatively low investments . However, they have higher operating costs compared to coal-fired power plants . These result from a somewhat lower efficiency of around 39% and, above all, higher specific energy prices of the natural gas commonly used compared to those of coal. The exhaust gases of the turbine still possess a high when leaving the turbine temperature , they can therefore be used to heat a steam boiler in the combined cycle (CCGT) are used; this enables efficiencies of around 60% to be achieved. In addition, the exhaust gases can also be used to operate thermal seawater desalination plants. This is often used in the Middle East, such as in Saudi Arabia, the United Arab Emirates or Kuwait. Very small units can be used in combined heat and power plants (CHP).

Advantages of a gas turbine power plant are the ability to black start and the quick start-up within about seven minutes. Such systems are therefore mainly used to cover load peaks in the power grid . For example, the West Berlin gas turbine power plants in Charlottenburg and Wilmersdorf played an important role until 1989 (when the Wall came down). In the event of a total failure of the brown or hard coal power plants, BEWAG had an emergency plan according to which the gas turbine power plants had to provide the required output during this time.

It is not uncommon for there to be several gas turbines at one power plant location. One example is the Thyrow gas turbine power plant, which originally had eight gas turbines.

Types

A distinction is made between heavy (Heavy Duty) and light construction (Aeroderivate).

Heavy construction

These turbines have an output from approx. 50 MW to over 340 MW and are particularly suitable for stationary continuous operation in large power plants. The longest possible service life is an important design criterion for this type of gas turbine.

Light construction

These turbines with an output of 100 kW to 40 MW are mostly derived from jet engines for aircraft ( aeroderivatives ) and are preferably used in industrial power plants. Here, these turbines are often part of a combined heat and power system or a combined cycle plant. As their starting time is only a few minutes, they are also suitable for emergency power generators.

safety

Gas turbine power plants are considered to be relatively reliable. However, on February 7, 2010, a serious accident occurred at a gas -fired power plant in Middletown, Connecticut, which was in trial operation . A gas-air mixture was accidentally ignited when cleaning a pipe. The subsequent huge explosion was still clearly noticeable at a distance of over 20 km.

Individual evidence

  1. ↑ Patrick R. O'Donoughue et al .: Life Cycle Greenhouse Gas Emissions of Electricity Generated from Conventionally Produced Natural Gas. Systematic Review and Harmonization . In: Journal of Industrial Ecology . tape 18 , no. 1 , 2014, p. 125-144 , doi : 10.1111 / jiec.12084 .
  2. ↑ rwe.com brochure "Kraftwerke Lingen", page 10 (PDF file; 1.26 MB)
  3. ↑ wikinews of February 7, 2010

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