Race against the onset of winter

20 December 1999

After the war in Serbia, and the return of the Kosovar refugees, ensuring a reliable supply of power became a matter of life and death. How was power provided?

The world watched as Kosovo was torn apart this summer. When the bombing stopped, and the refugees returned home, there was a race against time. The race was to install power before winter.

The problems facing the reconstruction team were not merely the result of bomb damage. Other problems came about as a result of a decade or more of neglect and poor operation and maintenance, and the loss of the vast majority of removable equipment when the Serbian forces pulled out of Kosovo.

All mobile equipment had been removed from the mines and power stations. All useful items and spare parts that could be moved were taken, all information was either removed, destroyed or made difficult to obtain.

Problems in Kosovo

The main challenges in repairing the Kosovan power system are:

Lack of supplies and equipment. When the Serbian forces pulled out of Kosovo, they removed as much equipment as possible. This included tools, electrical plant and mining equipment. The removal of the large bulldozers was a particular problem. The open-cast lignite mines provide the coal for the power plants, and six such bulldozers are needed to strip the overlying soil from the coal seams. Only recently have the first two been made available. This took place when Richard Caborn, UK Trade Minister, made a trip to Kosovo. On hearing of the bulldozer problem, he made money immediately available from the UK to hire two bulldozers.

Mines and unexploded ordinance. The problems posed by these are obvious.

Lack of trained personnel. Most of the senior plant operators were Serbian, and have left Kosovo. There is a shortage of trained operators. It is crucial to ensure that the workforce receives technical and managerial training. Many of the Kosovar technical engineers and staff have returned after an enforced absence of 10 years.

Poor maintenance and management. There has been little investment in the power system, which deteriorated over the years. Kosovo A was in such a poor state of repair that operating it poses dangers to both personnel and the environment. The only reason it is being operated is because there is no alternative to meet the expected power demand this winter.

Lack of arrival of promised funding. Mott MacDonald estimates that £90 million is required to see Kosovo through the winter. There has been no shortage of promises of funding; far more than the required amount has been promised. But the funding has been slow to materialise. Part of the reason for this delay has been the bureaucracy among the controlling agencies.

The two main power plants, Kosovo A and Kosovo B, were in a poor state of repair. Kosovo A was first commissioned in 1965, and consists of 5 units (see Table 1).

Kosovo B was built in the 1980s, and is in better condition than Kosovo A (see Table 2).

Key to the issue of getting reliable power supplies in Kosovo is getting the coal mines operable. Coal conveyors and additional earth-moving plant are needed for the mines.

Kosovo A

The plant was found to be in very poor condition. Mott MacDonald recommended that a risk assessment be carried out to see whether or not it should be kept operating. A four unit availability for the winter gives the most options, allowing for inevitable breakdowns.

Interbus transformers IT2 and IT3 are not available. IT3 has faulted and IT2 is missing. Either of these transformers is crucial for system security and to assist in achieving the voltage levels to synchronise the A station units.

All the boilers are in a poor state, with the tubing worn and corroded. Boiler pressure is limited to 110 bar to extend tube life and reduce the number of forced outages. Although this reduces the units' capacity, it is the preferred option to get through the winter.

There are large dust, pulverised fuel, and ash build-ups on the boiler and pipework, and around the walkways and gantries. This is a serious safety hazard. A1 boiler is in danger of collapse if the dust is not removed.

The transmission system is very insecure, creating a potential risk of serious plant damage and can create a safety hazard for staff attempting a restart during hours of darkness.

Kosovo B

Units B1 and 2 turbine low pressure blades have cracks, and Unit B2 high pressure steam chest has cracks developing. ABB Alstom estimates a necessary downtime of 6-8 weeks to carry out inspections and refurbishment.

Unit B1 and 2 standby boiler feed water circulating pumps were not available. One is at KSB Austria works, already repaired and awaiting final payment. The other, like so much else, was removed to Serbia, location unknown. These need returning to site to give security in case the duty pumps should fail.

Unit B1 standby boiler feed pump is not available, having been removed to Serbia.

The boilers were not preserved with chemicals when shutdown and drained of water. Corrosion will probably cause problems with water and steam purity on pressure raising.

Mott MacDonald believes it will be possible to 'nurse' the units through the winter.

Common to both plants

A procurement and funding mechanism must be quickly established by UNMIK (United Nations Mission in Kosovo). Spares, tools and services are urgently required.

Suitable communications are required. Chemical and fuel supplies must be consolidated before bad weather sets in. Protective equipment for workers in harsh environments must be provided quickly. A training and development programme is urgently required.

Maintenance and operation strategies have to be reviewed. A comprehensive management and planning system must be put in place to coordinate these activities.

Health and safety standards are inadequate. Staffing levels must be reviewed, but Mott MacDonald recommended leaving this review until after the winter to avoid distractions over this crucial period. Currently, the power sector employs over 9000 people. A balance must be struck between providing employment and income to a region desparately needing it and operating an efficient electricity company based on a Western model.

Transmission system

The Kosovo transmission system consists of 400 and 220 kV grids feeding a 110 kV ring, with interconnecting circuits to Albania, Macedonia, Montenegro and Serbia. Before the war, Kosovo was an exporter of power to these countries. All parties are keen for Kosovo to export power as soon as possible.

The transmission system has been in a very precarious condition. The current position is:

None out of the three 400 kV circuits is in service.

Eight out of eleven 220 kV circuits are in service, although some of the circuits currently in service are damaged.

Twenty-four out of thirty-five 110 kV circuits are in service.

The Kosovo power system is being operated in two sections, with Albania feeding Prizren, and the remainder (including all generation) synchronised with Serbia. This arrangement is to reduce loadings on the interconnecting circuit to Albania, which has severe conductor damage.

Demand has been up to 290 MWe, and total generation from Kosovo A has not exceeded 180 MWe. Power has been imported from Albania and Serbia, although the only formal arrangements for cross-border transfers were set up with the former Federal Republic of Yugoslavia.

The operating condition is insecure. There have been several system collapses, mainly due to failure of the interconnecting circuit with Serbia. Load reduction is applied regularly, particularly when synchronising a generator at Kosovo A.

The facilities at the despatch centre in Pristina are poor.

Facilities for controlling the power system are inadequate. No metering or other indications are relayed back to the despatch centre. This is compounded by the lack of reliable communications to all substations. Decisions on where to carry out load reductions are governed by what communications are available.

A System Control and Data Acquisition (SCADA) system was installed 4-5 years ago, monitoring 4 key substations. Staff are unable to access the system as it has been left immobilised by former Serbian employees.

System restoration

Urgent remedial action is required to give the power system security over the coming winter. Several factors must be borne in mind:

System availability and reliability.

Generation availability and reliability.

Interconnector availability and reliability.

The cost and expected dividend from expenditure in any one of the above areas.

Expected demand levels.

Access to site, which may require mine clearance prior to insepctions. Access will deteriorate with the onset of winter.

Interconnectors

Albania

There is only one interconnecting circuit to Albania. The busbars at Glogovac must be operational it to be effective, but they have been damaged. Although Albania is a net importer of energy, its hydro-based system complements the Kosovan thermal-based system.

Macedonia

There are 4 connections to Macedonia, but only one 110 kV link is in service, feeding a small (2 MWe) section of the Kosovo system. Macedonia wishes to restore the 400 kV and 220 kV links if there are sufficient connections to other utilities.

The Electric Company of Macedonia (ESM) has only 220 MWe of surplus capacity over demand. This includes 210 MWe of mothballed oil-fired generation, which ESM is reluctant to operate, due to the high cost of fuel. ESM will take power from Kosovo.

Montenegro

The Montenegro power system has a capacity of 840 MWe and peak demand of 615 MWe. In 1998, Montenegro was a net importer, and cannot reliably supply power for Kosovo.

Serbia

There are 4 circuits to Serbia. Only the 110 kV and 220 kV connections are currently in service. The 220 kV circuit has had a number of trips, due to unknown problems in Serbia.

Role of the Armed Forces

In June, the departing Serbs shut down everything. The power plants and coal mines are in the British zone, and the British army had to get the plants operating. This was achieved by Royal Engineers and local people working together. The British Army has added power plant operation to its training for engineers. This is increasingly important with the growing number of peacekeeping deployments.

Mine clearance of transmission lines must be carried out in liaison with K-For and UNMIK (United Nation Mission in Kosovo). Mott MacDonald engineers indicate the priority areas that need to be cleared, and K-For and UNMIK allocate resources to clear these areas.

New structure

There is a balance to be struck between establishing a profitable system and getting through the winter. People need work and income now. It is not viable to press for an immediate solution to an overmanning problem.

Local people find it difficult to accept the low levels of temporary pay set by UNMIK, at an average of DM225/month.
Tables

Table 1: Kosovo A plant details
Table 2: Kosovo B plant details

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