A wealth of different backgrounds and experience are some of the strengths of the staff at the Combined Cycle Gas Turbine (CCGT) at Poolbeg Power Station, according to Martin McConnon, Production Manager, at the plant. “We have an informal, but focussed, working relationship and there is a real commitment to keeping the plant in top class condition and continuing the excellent performance figures since the plant was commissioned. There is a great sense of pride and ownership in what we do and this creates a good working atmosphere for all the staff.”
The CCGT generating plant has a total maximum output of 494 MW consisting of two 157 MW Siemens V94.2 gas turbines fired on natural gas or distillate, two Austrian Energy heat recovery boilers (HRBs) and one Siemens 180 MW steam turbine in a 2-2-1 layout with a high level of automation. Diverter dampers are installed between the gas turbines and the heat recovery boilers and this improves the generating flexibility of the plant as, for example, both gas turbines can produce electricity in the event of a steam turbine shutdown or both gas turbines and the steam turbine can produce electricity in the event of a boiler shutdown. Other ancillary plant installed includes CW pump house, Water Treatment Plant, Electrochlorination plant and Auxiliary (or start-up) Boiler. The first gas turbine went into service in 1995, the second in 1999 followed by the steam turbine and ancillary plant in 2000.
While the CCGT plant is staffed by a core group of 21, they avail of a broad range of services from Poolbeg Thermal plant including safety, engineering, technical, chemical and administrative support. The Poolbeg Shift Manager has responsibility for the operation of both the Thermal and CCGT plants. In particular, maintenance staff from the Thermal plant are called on at critical times like an overhaul or when various other maintenance tasks are being carried out. As well as paying tribute to the staff at the Thermal plant for their co-operation and support at these vital times, Martin McConnon also acknowledges the tremendous back up received from various plant specialists in Generation Technology based in Head Office.
Safety has to be the major priority in the CCGT. A lot of effort has been put into improving the access to different parts of the plant from a maintenance and operations aspect over the past two years and into ensuring that maintenance and operational activities are carried out safely. "Some people may feel that there are fewer safety (and technical) challenges due to the fact that the CCGT is relatively new but this would be the wrong attitude". A Lost Time Accident at the plant in August 2004 underlines this and Martin McConnon emphasises that there is no room for complacency where safety is concerned.
“We are critically aware of our environmental responsibilities. The gas turbines for example, are equipped with modern dry low NOx burners and continuous emissions monitoring systems. We must operate within the terms of our EPA Integrated Pollution Prevention and Control License (IPPCL) and keep an eye out for improvement opportunities”.
The plant performance has been very good with the average availability of the gas turbines since the last major overhaul in 2002 running at 96.1 % for CG14 and 97.05% for CG15. The forced outage rate or FOR for the two gas turbines is 0.6 % and 0.15% respectively for the same period.
“I suppose that good performance does not happen by accident. A lot of effort was put in at the design stage and exhaustive testing took place during the commissioning phases to ensure/prove plant reliability. While it is important to install reliable, proven plant technologies it is also critical that maintenance is carried out effectively at the appropriate time. It is also important that plant and design faults are investigated fully and modifications proposed and made where appropriate and the CCGT staff certainly contribute hugely in this area.”
Martin McConnon readily admits that one of the major contributors to the performance of the Combined Cycle plant over the years is in having the right mix of skills and competencies required to run a modern gas turbine plant. “While it is vital to have staff from a variety of backgrounds, it is only through effective teamwork that you can realise the benefit. Having been involved with the CCGT from the commissioning phase I was aware that teamworking would be essential for the effective operation and performance of the plant. However, I have seen it evolve in a way that was not deliberate or contrived. People genuinely want to be able to contribute on the basis of their skills and experiences. You are certainly never short of advice or positive challenges from experienced staff with strong personalities.”
“An important feature of the CCGT is relationships and a positive working atmosphere. The staff in the CCGT Production Team are all from Poolbeg and are from varying backgrounds -- electrical, mechanical, instrumentation and operations. The 494MW plant has shift manning levels of 4 per shift with a minimum of 3 which can decrease if different portions of the plant are out of service – for example during overhauls. For staff who had been on shift previously in the Thermal Plant the main challenge was getting to grips with the technologies of the new plant whereas staff from a maintenance background had also to get used to the shift aspect.” However, Martin McConnon believes that the appeal of trying something new and flexible attracted many staff.
Staff who have retired in recent times from the CCGT or moved on to different locations, contributed a huge amount to the plant and have certainly left their mark. Four of the Production Team; John Loughlin, Dermot O’Neill, Paddy Murray and Tony Swan availed of the VS scheme and left the company in Autumn 2004. The previous Maintenance Team Leader, Padraig Dooley, is currently on a course as part of the Scholarship Scheme. Nicholas Tarrant, Production Manager CCGT until October 2004, is on assignment as Production the Thermal Plant. “This meant a large change in a small group of people and we keenly felt the loss of those people when they left,” says Martin.
“We are currently in the planning phases for our Gas Turbine Major Overhauls in 2006 and a lot of effort is being dedicated to this important project. It is the opportunity to carry out prescribed maintenance, to address problems and to ensure that good performance continues into the future.”
“The Poolbeg Combined Cycle has performed so consistently that it can sometimes seem to be taken for granted. So this is a welcome opportunity to acknowledge the tremendous performance of the plant and to recognise and thank all those that have made it happen. The consistently excellent results are a credit to all that have been involved over the past ten years and more: those who were involved in the design, construction and commissioning of the units, those who provide back-up and advice from Generation Services, those that provide support from within Poolbeg and particularly those staff, both past and present, that work directly in the Combined Cycle.”
Station Manager, Dublin Stations.
Philip Wafer started work in Ringsend in 1977 and after an initial period on day work he joined the shift staff as an Auxiliary Plant Attendant. When he moved to Poolbeg Thermal Station as a Unit Assistant he accepted that shift work was going to be very much a part of the job and so he has organised himself around the cycles he works. Philip joined the staff at the CCGT as a Production Team Member and then Team Leader and told EM he has seen it grow from one gas turbine to the state it is now. "This has kept me busy and we very much work together here, someone will always volunteer to help if a colleague needs assistance or a different perspective. Technology has always attracted me and I am something of a gadget freak. What appealed to me here was that it offered a new way of doing things. The difference here is I get to do a bit of front line maintenance and a bit of office work as well as operating the plant." The actual shift is a regular 9 day cycle and while night shifts probably do take their toll, Philip says he has been working on shift since he was about 22 so he basically accepts it as part of the job and works around it.
Myles Meagher joined ESB in 1974 as an electrical apprentice. He moved to the CCGT in 1994 working initially on a 2-shift cycle prior to the full commissioning of the plant. He is now a Production Team Leader at the station and he says that the new plant has opened up a broader range of duties to him. "Previously I would just have been involved in purely electrical duties but I am now able to carry out front line maintenance and operations work. It is much more satisfying and fulfilling with a greater range of tasks available," he told EM. As with most of the staff at the CCGT, Myles has been able to pursue a number of training courses, including a recent course with Siemens. "From my point of view the figures speak for themselves on the great teamwork we have here. If you look at our availability and reliability figures you will find it points to how well the team operates together. Staff here would say they much prefer the new system of working – with such a wide range of skills and backgrounds there is always someone on the team available to assist or to come forward with alternative view," says Myles.