Serbia: The status report of power generation facilities of EPS power utility company, interview with EPS Production directorate manager Vera Stanojevic

18. December 2013. / News Serbia Energy

Serbia: The status report of power generation facilities of EPS power utility company, interview with EPS Production directorate manager Vera Stanojevic

Thermal units withstood with the minimum overhauls. –For the nine months it was achieved the highest production from 1990th  and the largest surplus from 1995th . –  Minimum planned and unplanned interruptions.  – Public procurements complicate the preparations for the winter.

After the maximum realization of nine-month electricity production since 1990th, the similar results for the nine months this year were achieved in the EPS power plants. Vera Stanojevic, Director of the Department for the electricity and heat production in the PE EPS Directorate for the energy production, said that one of the largest ten- month production in the last 12 years was achieved in the period from January-October 2013th and that this was a period marked by a large surplus, the most one during the time when EPS power plants headed upward in every respect – both by operational readiness and production increase. With Vera Stanojevic, however, the story of production results does not end here. On the contrary, just starts out. Her work analysis of EPS power plants contain a lot of information about the work of each plant, each thermal unit and hydro aggregate. Especially shows the weighted unit for each power plant (taking into account the strength of each unit), and for the thermal and hydro sector, and then also for the EPS weighted unit. Thus, the whole book of numerical data and graphs, that our interlocutor discloses in general, but also with a lot of detail, is always presented in front of the participants on the regular meetings of the EPS Directorate for the production with the directors of EPS subsidiary companies in production for each analyzed period, month, trimester, quarter, or a long time period. It is not easy to follow her, especially to the layman journalist. We talked about what did reflect the maximum production and how much it was a guarantee for a serene winter.

Is the production coefficient the most important indicator of power plants’ work?

Production cannot be assessed on the basis of only one parameter. That is why there is not the most important one. The amount of produced energy is a starting point, but it has to be taken into account, for example in the case of TPP, whether it is a base or peak unit, how long the unit was in cold or warm reserve, how long did last the planned or unplanned downtime. For ten months of this year we had both minimum planned and unplanned downtime, but therefore the thermal units were in the longest hot and cold reserve since 2001th. All that influenced on the TPPs’ highest ten- month production since 1990th, but the question is whether these are the maximum TPPs capability. The production coefficient represents the average produced power during the units’ operation. For the ten months 2013th it is 90.5 percent lower than in the same time 2012th and it is the only parameter that is not the best in the last 20 years. Let’s remember, last year was extremely difficult in terms of electro energetics. We had an extremely cold winter, low inflows, hot summer and great electricity import during the winter. This year, there is not all that. Unfortunately, the production coefficient, which began to grow in 2008th, had not reached the maximum realized value of 95 percent from the 2011th. This year it was reduced due to system limitations: large warm reserves and units involvement in the secondary control during the high flows of the Danube and Drina.

This year in October, for example, in the thermal sector, was realized the longest working hours but not the highest production. The reason for this is the long period that units spent in the warm reserves, what TENT A units show the best. Among the involved units, the unit A2 was the longest “suppressed”, which spent 599.7 hours in a warm reserves. Two units A1 and A3, had similar time in a warm reserves, so TENT A in October, achieved its lowest production coefficient of only 80.4 percent.

Did the cold reserve have the same effect?

In the ten-month period, thermal units ready to operate spent in a cold reserve most of the time since 1995. They were not engaged for 4.6 percent of calendar time. Since then, the weighted TENT units were stopped 5.7 percent of the time. Because there is not enough detected coal reserves from MB “Kolubara” and because the calorific value of mined coal is determined by the quality of available fields. This is a problem we are facing for a long time. It was not invested on time, among other things, in the mining capacities, which results in such current state of coal production. Unlike equipment at “Kolubara” mines and delays in new fields opening, TENT plants are largely revitalized and can realize higher production. As coal is their limiting factor, we tried to extract maximum utility from those quantity and quality, so the producing mainstays were more efficient and reliable thermal units in SC TENT. Such a problem does not exist in a “Kostolac “. Units in Thermal power plants “Kostolac “were only 1.1 percent of time in cold reserve. The coal quality and quantity were not limiting factor, as mine “Drmno“is qualified to settle the production of both plants. It should be also said that the cold reserves time affected that we had a very favorable hydrological situation in the first half of the year, when HPPs exercised the maximum production, which determined the TPP engagement.

In what way did the planned and unplanned delays affect the overall score?
Planned delays were really minimal, with the least amount of time for repairs since 1995th. No one can plan unplanned delays, but can prevent them by well plant maintaining. What did help us this year was the maximum number of the units’ revitalization in the last ten years and the operations to remedy the equipment shortcomings during the cold reserve time, according to the possibilities. As a result, we weathered well most of this year and it may be so in just one year. It would not be good to continue with restrictive planning delays. In this case, we would face with the problems that we had in the late nineties, especially the 2000th. As time for planned delays was shorter, the time for unplanned failures quickly grew. Admittedly, we have not finished yet this year. A warm October and mid-November disguised the winter entering, so that we expect challenges of increased spending. Therefore it is important to adopt the Plan Rebalance for this year and, though it is already late, to prepare resources for the proper maintenance in the coming winter months. When I say that, I have in mind difficulties in procurement, which greatly slowed the spare parts procurement and service operations contracting from this summer. 

On what basis do you assess well operational readiness of units?

Thermal units in the EPS system showed excellent operational readiness by being online 80.8 percent of calendar time. With such a maximum engagement, units had the smallest number of unscheduled delays, and while troubleshooting time was minimal, observed since 1995th. Although these TPPs operated with average lower forces, they produced 10 percent more power than last year, because they were operating for longer time. As a result, TPPs ten-month production is higher this year than the annual productions of the same units in the period since 1992nd the 2004th. I do not mention generators in hydro power plants in this context, because they are always ready to take advantage of all the available potential inflows, although, until recently, two important aggregates were revitalizing. The fact of their higher production of nearly 900 million kWh compared to the same period in 2012th is enough proof of the good HPP work.

How did it affect the overall business results?

On the whole, the results are excellent. EPS power plants produced a total of 30.676 billion kilowatt – hours and achieved a cumulative surplus of 3.323 billion kWh for ten months 2013th, the highest since 1995th. In addition, it is important to say that planned delays were reduced by ten percent in this year, and that the total financial resources for maintenance were reduced by 25 percent, all in accordance with the financial capabilities considered at the end of last year. However, due to the high surplus and a very good production with reduced operating costs, a significant portion of energy was sold on the open market, allowing the improvement of the company financial situation.

Save the achieved         

Why there are fears of the winter consummation?

The main reason is that we in EPS have painful experience with unfinished repairs in nineties. The other thing is that it has to do with complex installations, for which have been prescribed maintenance cycles according to the technical standards, and all developed companies in the world respect and apply them, in order to maintain the equipment and operational readiness of the plant. It is a multi-year cycle, which defines the time intervals for capital and standard repairs and revitalization, but also what this works volumes include. The operational readiness was good this year, and the production was excellent, because we organized it in order to primarily use the available water and the most efficient thermal units. Besides, once again, the funds for equipment maintenance were reduced. Therefore, it is important now to use as much as possible the upcoming time and prepare for the winter, in order not to degrade all these excellent results – said Vera Stanojevic.

Source; EPS

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