Bouchain is not any site. This is EDF’s flagship gas plant, but also the world’s first to operate GE’s 9HA Gas Turbine since 2016. The outage itself is a sign of the engine’s accomplishments. GE’s HA-fleet’s cumulative operating hours are now approaching 800k hours. The fleet-leader for the 9HA had accumulated over 24,000 operating hours of successful operation prior to the planned inspection.
The scheduled maintenance work was essential in a site that powers 680,000 homes. When it was commissioned, the 9HA Gas Turbine installation at Bouchain was recognized for a world record as the world’s most efficient combined cycle power plant because of its impressive ability to convert more than 62% of fuel energy into electricity. In addition to record-setting efficiency levels, the 9HA gas turbine delivers enhanced flexibility, and can reach full power in less than 30 minutes. This allows EDF to respond quickly to grid demand fluctuations, integrating renewables as necessary, supporting the COP21 agreement and its goal to reduce greenhouse gas emissions.
After operating for 4 years, the time had come for the giant’s first major inspection. Nearly 400 GE and FieldCore experts, EDF technicians and sub-contractors rose to that challenge, totaling about 20,000 work hours this past summer. The GE team was responsible for the gas turbine hot gas path inspection and the checkups of the steam turbine and generator. By checking core components’ health and performance, the Bouchain site is set to operate further and generate power within the region for years to come.
“We are very pleased with the GE teams” Said Philippe Lambin, Head of Maintenance at EDF. “Safety was the priority to make the outage a success and GE engineering and operational teams were very committed to point out and fix all technical issues. Their work and dedication ensured that the gas turbine, steam turbine and generator, have reached the highest level of reliability and efficiency for the next run and the forthcoming winter.”
Opening a turbine that weighs as much as a fully loaded Boeing 747 would be a challenge in any circumstance, with EHS a top priority. But with the COVID-19 pandemic raging globally in the summer of 2020, many additional protocols had to be followed.
For instance, to deliver the outage on time while following social distancing requirements, the originally planned team shifts were changed by a few hours to avoid any contact between the teams. Further procedures were applied across the GE areas, but also throughout the plant site, enforcing social distancing and mask wearing at all times.
With restrictions on international travel, the expert team from abroad could not travel to the site to introduce the brand-new tools developed to help the teams execute the plant outage. The teams relied on virtual meetings to brief the crew on site. These tools, specifically developed for the 9HA Gas Turbine, were a core component of the outage, helping the team to open and access the Hot Gas Path but also turn the gas turbine shaft for alignment checks.
“The teams were extremely excited to open the first 9HA Gas Turbine ever”, said Olivier Schmitt, GE Technical Contract Manager. “We were able to see how the engine was running and, by replacing components that had run for thousands of hours, we were able to help EDF get the most from their investment. Plus, the learnings here will aid GE in our continuous quest for technology and plant performance improvement.”