Increased output, greater efficiency and enhanced operational flexibility are among the expected benefits of an upgrade to be carried out at the Thisvi combined cycle power plant, in Greece, in operation since 2010. Ansaldo Energia has been awarded the contract by plant owner Enerwave SA, part of HELLENiQ ENERGY, to implement a “comprehensive enhancement” of the plant’s AE94.3A gas turbine, with completion scheduled for March 2027. Renewal of a previous long-term service agreement (LTSA) with Ansaldo Energia will provide technical support for the next 14 years.
The upgrade will also see the plant’s ramp rate increased, ensuring rapid response to grid fluctuations linked to the growing penetration of renewable energy. Overall, the project once again demonstrates how upgrades can enhance the value of existing assets.
Reliability package for Damhead Creek
Meanwhile, in the UK, Mitsubishi Power has announced the successful completion of an upgraded reliability package at the 812 MW natural-gas-fired Damhead Creek gas turbine combined cycle (GTCC) power plant, located on the Hoo Peninsula, Kent, UK, and owned and operated by VPI. Implementation of the package aims to achieve better start up response, increased performance and improved reliability. It also includes an upgrade of the turbine control system.
Efficiency and reliability upgrades are vital for gas turbines, says Mitsubishi Power, given that gas-fired power plants are increasingly being used as flexible power generation assets to support intermittent renewable energy. This is the case in the UK, which has a high degree of renewable penetration, requiring gas fired power plants to frequently start and stop according to system needs.
“In today’s power grid, GTCCs are crucial – not only for keeping the lights on for homes and businesses – but also for the scale-up of renewable energy, by delivering flexible and reliable power generation,” said Javier Cavada, president and CEO for Europe, Middle East and Africa at Mitsubishi Power. “There is no renewable energy without thermal generation providing the reliability, flexibility and security of supply. This evolved role for gas fired generation is critical – but it is also one that places significant stress on GTCC plants generally and on the gas turbines specifically. The completion of the upgraded reliability package at Damhead Creek will ensure that the plant is able to deliver power…in a more efficient and more reliable way for years to come, and in doing so, will ensure a more sustainable grid by supporting the integration of more renewable energy sources.”
The gas turbines were originally supplied to Damhead Creek by Mitsubishi Power in 2000. After purchasing the plant in 2021, VPI signed a service agreement with Mitsubishi Power to deliver a major programme of investment in the site to improve efficiency and reliability. This included maintenance, management, parts supply and remote monitoring services for the gas turbines and delivery of the upgraded reliability package.
VPI, owned by energy trader Vitol, operates in Ireland and Germany, as well as the UK. It has more than 4 GW of operating assets, including two projects under construction, and is the largest operator of battery storage in Ireland. Its development pipeline includes more than 1 GW of battery storage in Germany, and it is also working on a proposed carbon capture retrofit project at its 1240 MW Immingham CHP plant in the UK.
HE upgrade at Coryton
Elsewhere in the UK, GE Vernova has completed a major outage and installation of two of its High Efficiency (HE) upgrades at InterGen’s 800 MW Coryton combined cycle power plant, located 30 miles east of London on the River Thames.
The HE upgrade consists of a package of improvements installed across the two GT26 gas turbines, compressors and combustors. These enable Coryton to deliver up to additional 85 MW, surpassing the expected 77 MW, and improve unit efficiency by 2.46%. The upgrades aim to also extend maintenance intervals. Vernova says its Coryton project team, comprising over 300 experts from across the globe, collaborated closely with InterGen to form a unified team, which completed more than 122 000 man-hours of work with zero recordable EHS incidents.
With Coryton, eleven GT26 units having the HE upgrade are now in operation. GE Vernova says it has invested significantly in the development of the upgrade, which was introduced in 2019. It aims to combine the best from both GE Vernova’s F- and H-Class fleets, with additive manufactured parts and innovations in aerodynamics, material science, and combustion dynamics — and achieves “a leap forward in efficiency, output, and maintenance interval extensions.”
