Combined cycle gas turbine

1. Marek Kras

2. A combined cycle gas turbine power plant,
frequently identified by CCGT shortcut, is
essentially an electrical power plant in
which a gas turbine and a steam turbine
are used in combination to achieve greater
efficiency than would be possible
independently. The gas
turbine drives an electrical generator. The
gas turbine exhaust is then used to
produce steam in a heat exchanger (steam
generator) to supply a steam turbine
whose output provides the means to
generate more electricity. However the
Steam Turbine is not necessarily, in that
case the plant produce electricity and
industrial steam which can be used for
heating or industrial purpose.

3. •Main Gas Turbine Manufactures:
General Electrics, Simens Westinghouse
& Alstom
•Approximately Cost per MW – 0.7mln E
•Efficiency approx 40% for gas turbine
however in the CCGT plant the efficiency
is 50-60% (even higher for cogenerated
plant)
•Low Green Gas Emission C02, NOx &
SOx
•Chepear comparing to other technology
e.g. CCS
•Lifetime 30-40 years

4. 220kV Tabert
Substation
110kV Clahane
Substation

5. Natural Gas. Resources not available in Ireland
Synthetic Gas from coal.
Resources not available in Ireland
Fuel Oil. Resources not available in Ireland
Biogas from forestry, domestic and agricultural waste.
Resources available in Ireland

6. Variable CCGT High Efficiency
Cogeneration
Transmission Network Lower Impact Higher Impact
Power Losses Less power losses Higher Power Losses
Heat Market Required Not Required
Fuel consumption -33% +33%
CO2 Emission -67% +67%
Water Consumption -30% +30%
Capital Cost per kW delivered 630 1200

7. Grid Code contains general conditions and rules for general application.
The specification and conditions for each application are adjust individually.
Those information are included in Grid Connection Offer & Agreement
between developer and Transmission Operator TSO.
•Client (Requires connection) and TSO must implement Grid Code specification
during each stages of the project, for project above 10MW
•TSO may disconnected or terminated the Grid Connection Agreement
if the Grid Code is not implemented by client.
•The Implementation of the Grid Code may have significant impact on the cost of the
Grid Connection
•ESB Networks Electrical Safety Rules must be implemented

8. •Capacity of the transmission lines
• Small Infrastructures of the High Voltage Lines
•Distance from Energy Load Centres (West Coast)
• High Cost of Design and planning permission for
Shallow Connection, significantly for OHL 220kV
•Planning Restrictions regarding OHL Construction

10. Variable Cost
Gas & Steam Turbine
Generator
210’000’000
2 bay 110kV/220kV
Substation
4’420’000
220kV OHL 710’000/km (12km)
110kV OHL 320’000/km (15km)
Buried Cable 500MVA
(optional)
2’150’000/km
Total Cost 227’740’000