Alstom pulled together a multi-national and multi-disciplined team in double-quick time in order to put a fire-damaged power plant back on line before the Kosovan winter set in.
Kosovo’s recent history is well known, and images from the recent civil war are embedded in the minds of people the world over. But since the journalists and TV cameras have gone home, the region has quietly being rebuilding its infrastructure under the watchful eye of the United Nations Interim Administration Mission in Kosovo (UNMIK).
However, Kosovo suffered a setback on July 19 when its main power plant, Kosovo B, was hit by lightning, causing a fire which damaged both units 1 and 2. At unit 1, much of the electrical distribution system and control system was completely destroyed, but at unit 2, the damage was limited to the destruction of the control desk.
Figure 1. The Kosovo B lignite fired power station is located in Obilic, near Pristina
Figure 2. Extensive damage was caused to both units at the power station
The region suffers from extremely cold winters, and UNMIK’s urgent priority wa.s to get the power supply up and running as soon as possible, otherwise 70 per cent of Kosovo’s population would be left without electricity over winter.
Alstom was the original builder of the 2 x 339 MW lignite-fired power station in Obilic, near Pristina and has been involved in reconstruction work at the plant since the end of the Kosovan war in June 1999.
UNMIK called in a team from Alstom’s Power Sector to assess the damage. Alstom proposed repairing the least damaged unit, unit 2, by December. Alain Feraud, from the Power Service activity within Alstom Power, explained: “We were the only company to propose rest.arting one of the units before winter. We had done this type of work in other power stations before and we had the experience and the range of equipment to be able to confidently propose this solution.”
UNMIK awarded a g10.9 million contract to a consortium comprising Alstom and Innogy to carry out the repair work for Kosovan utility Korporata Energjetike e Kosoves (KEK). Alstom’s Power sector was charged with supplying, installing and commissioning a new soft desk control room. Innogy was responsible for installing the necessary switchgear and cables for the 6.3 kV and 0.4 kV electrical distribution.
Alstom’s Power Service team from Belfort, France, arrived on site in late August and immediately renovated a room to house the new control equipment. The fire had not only destroyed the control equipment for both units but also the control equipment for various systems common to both units, such as water treatment. This common control system was previously housed in unit 1, but would now be rebuilt and housed in the unit 2 control room.
Figure 3. Alstom’s ‘soft-desk’ solution meant replacing a ‘manual’ system with a totally computerised control system
Alstom’s ‘soft-desk’ solution meant replacing a ‘manual’ system with a totally computerised control system. This meant that, within the tight time-schedule, workers at the plant would have to be trained in how to use the new equipment.
Alstom installed screens, and eight programmable logic controller computers that process all the information received from around the plant. The team then customised control software for use at the plant. The new equipment controls the boiler, auxiliary system, steam turbine, generator, power transmission, mechanical balance of the plant and all systems needed to achieve the required output at the plant.
The control room also had to be equipped to control the new power dist-ribution systems being installed at the same time by Alstom’s partner in the consortium, Innogy. Workers at the plant were trained by Innogy at power stations in the UK and then on site by Alstom in how to use the new control room equipment. Innogy provided operational support to KEK during the commissioning phase.
Innogy subcontracted the main components of the electrical work on a project basis to the Transmission and Distribution (T&D) Sector of Alstom, which defined the specifications, and supplied and installed the electrical distribution system equipment.
Jay Mehta, Alstom T&D UK sales, said: “We were excited to get the contract and we knew we could complete the job in the time. At the same time we also knew we had to move quickly.”
Within a week of signing the contract on August 30, an Alstom team from Berlin, Germany had its site manager, Micheal Waldau, at Kosovo B and, within two weeks, deliveries of tools and basic equipment from Germany and supplies of cable had arrived.
Innogy had already cleaned out the fire-damaged room where the electrical distribution equipment was to be installed. Alstom brought in local labour to do the work, overseen by two supervisory engineers flown in from Germany.
Power for the site is supplied at 6.3 kV and engineers installed two medium-voltage switchboards, one with seven circuits for the general auxiliary switchboard and one with three circuits for the interconnecter to coal-handling and ash-handling switchboards. The general auxiliary switchboard supplies power to workshops and office, fire protection equipment, general lighting, water treatment plant and the general auxiliary for temporary power supply.
Alstom also supplied and installed a 1600 kVA transformer, which converts power from 6.3 kV to 400 V. This then feeds 30 low-voltage circuits that supply compressors, a fuel oil pump, hydrogen plant, propane gas heating, emergency lighting, heating, water pump, a lift, ventilation system and a dirty water drainage pump.
When installations were completed, Alstom flew in two more engineers from Germany to carry out commissioning. “Our engineers were working very long hours over the last four weekends in order to get the job done,” said Volker Erfurth, T&D project manager, based in Berlin. “And they made sure everything was completed on time and to the client’s satisfaction,” he added.
“On a fast-track project such as this, it was essential that we worked closely with our partners at Innogy. At Alstom, we were able to bring in the best people from the Power and T&D sectors from all over Europe in order to get the job done and the lights back on in Kosovo for Christmas,” said Féraud.
Beating another winter
Following the success of this em.ergency repair, Alstom recently won a contract to make more extensive repairs at the plant. In February this year, an Alstom-led consortium won a R38 million contract to refurbish both units at the power plant for Kosovan utility KEK. The contract is once again being co-funded by UNMIK.
The contract covers the complete refurbishment of the electrical and control equipment and the restarting of Unit 1.
When this is complete, Unit 2 will be shut down and the electrical and control equipment will be refurbished. Both Units are due to be up and running again before the start of winter, 2003.
Alstom’s Power and Transmission & Distribution (T&D) Sectors are in consortium with the German firm Koch, which is responsible mainly for civil works. Alstom’s Power Sector will supply, install and commis.sion the P320 digital control system in each unit, upgrading the instrumentation and control systems of the boiler and steam turbine. The T&D Sector will provide a complete electrical system including medium-voltage and low-voltage switchgear along with MiCOM protection relays.
Féraud said: “The time schedule for carrying out the project is tight and the refurbishment work is a specialized job. Our consortium has the necessary experience and the proven ability to get the job done, to the satisfaction of the customer.”
Figure 4. The steam turbine units were back in operation in time for the winter