The construction of the Ptolemaida V steam power plant was decided by PPC in November 2007, under the chairmanship and managing director of Takis Athanassopoulos, when our country's electricity system was facing major power shortage problems.
It is characteristic that the demand for electricity in the period from 2001 until 2006 was growing at an average annual rate 4%, while there were very few private gas plants in the system.
The contract for the assignment of the project was signed under the chairman and managing director Arthouros Zervos in March 2013, while its construction started in December 2015.
It is a modern lignite unit, the largest ever built by PPC, with power 660 MW, which will also produce thermal power 140 MW, to support the district heating of the city of Ptolemaida.
The total development cost of the unit amounts to 1,4 billion. euro, plus 200 million. euros for the accompanying projects. The unit will be put into trial operation in the Fall 2022 and unexpectedly in the tests, the start of commercial operation is expected at the end of 2022 beginning next year.
last ten years, the decisions on Ptolemais V were strongly contested by many, inside and outside PPC, culminating, in the context of the policy of accelerated delignitization, the proposal to convert it into a natural gas unit, power 1000 MW, with the start of the relevant works on 2025. In today's situation, the start of operation of Ptolemais V is considered absolutely necessary for the country's energy sufficiency in the difficult months to come.
Apart from the unit's obvious contribution to the country's energy security, it is also interesting to see the effect it may have on energy market prices, and especially in DAM day-ahead prices (Day Ahead Market), which largely determine energy prices. For this purpose we use the DIEM platform (link), which has been developed at NTUA by the Smart Rue team and its partners in order to collect and organize electricity and natural gas market data published publicly by National and European organizations. For the needs of the article, market operation is simulated over time 1/1-30/6/2022, as if Ptolemais V had joined the system. The study uses the same hourly load and the same RES output, which is included in the system as a matter of priority. The same applies to hydroelectric production. The offers of the existing thermal units remain the same. The variable cost of Ptolemais V, estimated at €100/MWh, cost realistic, if we take into account a cost of purchasing CO2 rights of €80/ton, the high level environmental specifications of the unit (shows 1.05 tons of CO2/MWh) and its supply from the cheap mine of Mavropigi. The simulation is based on cumulative supply and demand curves, to which is added the available power of Ptolemais V, moving the intersection of the two curves accordingly as well as results relative to package order offers (block order). In the current operation of the single European market, special attention needs to be paid to the modeling of power exchanges through interconnections with neighboring countries, mainly Italy and Bulgaria. It is obvious that the operation of a large plant in Greece will also affect the markets of neighboring countries. For the purposes of the study, it is assumed that if the closing price of Italy and/or Bulgaria is higher than the closing price of Greece, energy from our country will be offered to neighboring countries and will obviously affect their prices. We assume that this energy will come from Ptolemais V, as a cheaper unit. For this reason a recursive function is implemented, by which it is removed from the power of Ptolemais V, the strength of the interconnections when some neighboring market price is higher and the closing price of the DAM is recalculated.
In the Figure 1 the evolution of DAM prices is shown, if Ptolemais V's bids were €100/MWh, compared to the prices recorded in the same period of its first half 2022. The average closing price of the next day market is formed from 237.05 €/MWh in 164.77 €/MWh. According to the way the market works, the total output is compensated at the closing price. From the sum of the price reduction per hour over the total hourly load, the energy purchase cost reduction results. From the load of each hour, the production of RES has been subtracted, which are mostly compensated with special prices (feed in, feed in premium tariffs). For the semester 1/1-30/6/2022 the reduction comes out equal to 1.35 about € billion. We note that this reduction is approximate and is a reduction in the cost of purchasing energy from DAM and not necessarily an increase in the System's profitability.
Similar conclusions can be drawn if Ptolemais V's offer was 125 €/MWh (Shape 2). In this case the average of the next day's market closing price is set to 177.22 €/MWh, which implies a reduction in energy purchase costs for the six months by approx 1.13 billion €.
Shape 1. Compare hourly next day market closing prices (DAM) without (recorded) and with the function of Ptolemais V (appreciated) with an offer of €100/MWh
Shape 2. Compare hourly next day market closing prices (DAM) without (recorded) and with the function of Ptolemais V (appreciated) with an offer of €125/MWh
It is obvious that the inclusion of Ptolemais V will contribute significantly to security of supply, since it is based on a domestic and controlled fuel, but that it can also affect the economic operation of the System. Even after the current energy crisis has passed, the role of such a unit in the long-term security of the System should be carefully studied in the context of a long-term energy planning. Of course, this does not mean that the current energy crisis should lead to a reversal of the energy transition policy, which will lead to a new crisis, environmental this time. The fair transition to an energy system based on the full development of RES is still a one-way street.
Nikos Chatziargyriou, NTUA professor, former vice president of PPC
Aris Demeas, Dr.. NTUA, Smart Rue Principal Investigator