Weather shapes the energy sector, Mr. Jovica Vranić, Director of Energy Planning and Management in the EPS Electricity Trade Department18. April 2013. / News Serbia Energy
In February last year, the consumption of electricity in Serbia, excluding Kosovo, was about half a billion kilowatt-hours more than the consumption in the same month this year. – The long drought affected the energy balance last year, and this year the days warmer than average with the large inflows have done the same.
In order to estimate how much costs were borne by everyone during winter time last year, especially the coldest month of January and February, it is necessary to have the information on how much coal, wood, gas or electricity have the citizens spent more than normal to get more or less warm; at what prices they paid for the firing and whether they had to take out the money out of their pockets during the frost or they could pay the bills when the sun warms up well. In the countries with developed statistical analysis all this is being recorded, calculated, analyzed and systematized so that for the future similar situations the measures would be undertaken in advance to endure with less difficulty the cold and drought that joined together last winter in Serbia.
In Serbia, there is no more profound analysis, but it is quite clear that the electricity situation is a synthesis of the overall energy portfolio and energy production and consumption. Most people use electric heating. So, this attempt to show comparative figures for February of the last and this year, primarily aims to construe and explain what happens when the outside temperatures are significantly below average, the inflows less than in a hundred year period, i.e. how much easier it is to endure winter when the mercury in the thermometer is above the average level in certain days, and water level rises to the threat of flooding.
Synthesis of all energy
We have spoken with Mr.Jovica Vranić, the Director for energy planning and management of the EPS Energy Trading Department, about the February indicators and experience. For starters, he told us that the difference between last year and this year February can be expressed in about half a billion kilowatt-hours consumed more when the mean daily temperature was minus three degrees Celsius.
– In February this year, the mean daily temperature was 4,4 degrees Celsius, so it was 2,5 degrees warmer than the 120-year average temperature for this month. Owing to the warm weather and not forgetting the reduced industrial activity, the sale of electricity to the end customers (full supply) reached “only” circa 3,2 billion kilowatt-hours, which is 8,1 percent less than planned. In same month last year, sales amounted to 3,6 billion kWh, taking into account that warmer days in the second half of February mitigated a very difficult energy situation. Thus, the mean daily temperature was stopped at only three degrees below zero, and in fact, in the first half of February we had the extreme cold weather, even minus 9,3 degree of Celsius. Under such outside conditions, on 7th February, a record consumption of 141,4 million kWh was recorded in Serbia without Kosovo and Metohija – explained Mr. Vranić.
He also reminded on the fact that the balancing of balance obligations and needs was much helped by the Serbian Government’s Decision to reduce the power consumption in the industry, which most manufacturers dutifully obeyed, Mr. Vranić said that even with such a reduction, the needs of consumers could not be met from EPS power plants, especially because the performance of run-of-river hydropower plants would decrease significantly due to drought, and “Kolubara” was in difficulty to provide a continuous excavation and transportation of coal to TPPNT for days, because of the frozen machinery, railway tracks and cars.
Both supply and security
– In this situation, the EPS power plants managed to produce about 3,2 billion kWh in February 2012, which could be enough for the consumption, but not for other electricity needs in Serbia. In order to meet all these needs and to ensure the safety of the power system operation, 500 million kilowatt-hours has been bought on the open market, not counting the regular supply pursuant to long-term and annual contracts, which amounted to about 96 million – said Mr. Vranić.
Our interviewee explained that in the first two months of the last year, a very small reserve in the system was held, which means that the coal-fired power plants operated at maximum power, that TPP-HPs were additionally engaged and supplied by fuel oil purchased specially on the market, and that the situation was especially complicated because of low inflow, which decimated the run-of-river hydropower plants production. Specifically, in February 2012, the run-of-river hydropower plants produced only 536 million with the inflows of the Danube amounting to 3150 cubic meters per second and the Drina inflows of only 230 cubic meters per second.
This year’s February was the complete opposite of the last year February. We have already stated what the difference in electricity production and mean daily temperature is between these two months. As regards the inflow, the February inflows this year surpassed not only last year inflows, but also the planned level. Average daily inflows of the Danube river were approximately 7,200 cubic meters per second, which is 3,000 cubic meters more than planned. The Drina river had the inflow of five hundred cubic meters per second, which is 200 cubic meters more than planned. Thanks to these inflows, the run-of-river hydropower plants production was close to a billion kWh, which is 52% more than the planned amounts.
In connection with the dependence of hydropower plants operation on the hydrological conditions, Mr. Vranić pointed out that reservoir HPPs this February provided the system with 23% less energy than planned (207 million kWh), because there was no need to engage more, and that in the same month last year they produced 331 million kWh, i.e. as much as was needed to assist thermal power sector and to maintain the stability of production in the total power system of EPS.
– Overall, in February last year, we had a power consumption of exactly 457 million kWh higher than the one in February this year, and the production by 270 million lower than in February this year. In the structure of production, it is particularly important that last February the production of run-of-river HPPs was 440 million kWh less than this February and reservoir HPPs production was by 124 million kWh higher. Also, the TPP-HP produced 97 million kWh more last February than in the same month this year. These are the reasons why EPS had to purchase additional power on the open market last winter, and in February as well – said Mr. Vranić
In 2013, the total hydropower production was planned at 70 percent probability of non-regulated inflow at the hydroelectric plant profile. These were the plans of EPS until 2004, and then they shifted to 50 percent, which increased the risk in business operations. To reduce these risks, in the portfolio of electricity, the production from hydropower in 2013 is no longer involved with 30%, as in the past decade, but with only 24%. Still, the weather is favorable, so that the share of hydropower plants in the total production went over 30 percent just in the first two months. Owing to this, in February this year, EPS has sold about 308 million kWh on the open market, and if we take into account that EPS did not have to buy the total projected amount for this winter, then the positive effect of warm weather and good hydrology conditions are obvious – Mr. Vranić said.
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