Opportunities for the Transformation and Development of Power Plants Under Water Stress Conditions: Example of Adamów Power Plant

Abstract

In the vicinity of the Adamów power plant, which operates in the catchment area of the Kiełbaska river, there is a significant shortage of water resources caused by the intensive use of water by the energy industry and agriculture. The development of the plant by replacing the outdated coal-fired (lignite-fired) units with modern gas and steam units may contribute significantly to reducing the negative impact on the environment and reduce the demand for water resources relative to coal technology. Gas and steam units are a much more energy-efficient technology. This implies a lower demand for water, a reduction in pollutant emissions, and greater operational flexibility, which enables the units to adapt to changing hydrological and environmental conditions. The high efficiency of these units limits the need for frequent water-refilling, while allowing for a more sustainable and stable production of energy. Based on an analysis of hydrological data for the years 2019–2023, it was estimated that water stress is observed in this catchment area on 198 days per year, which accounts for c.a. 54% of the hydrological year. Therefore, it is assumed that inter-catchment pumping stations with a flow of 0.347 m³∙s⁻¹ will be required. This sets the demand for water at 5.95 million m³ per year. The planned water transfer will be carried out from Jeziorsko reservoir on the Warta river through the catchment area of Teleszyna river. Moreover, there are plans for the reconstruction of the layout of Kiełbaska Duża and Teleszyna rivers, which would involve the restoration of natural run-offs, following the discontinuation of open-pit lignite mining. This will additionally be supported by the reduced demand for water in the water use system when using the modernised power plant. The analysed data made it possible to develop hydrological scenarios that take the future reduction in water stress into account by implementing plans to restore the former hydrographic system in the region. These investments would also foresee the creation of new retention reservoirs (in former mining pits) with a capacity of nearly 900 million m³, which will significantly increase the region’s water resources and retention potential, supporting hydrological and energy security for the years to come.

1. Introduction

As emphasised in reports by the Intergovernmental Panel on Climate Change (IPCC) [1,2], in recent years, due to climate change and the growing demand for water [3], measures related to the sustainable use of water resources have been posing significant challenges [4,5]. It is expected that the problem of water shortages will become more acute, strongly influenced by climate change as well as socio-economic processes related to the increased demand for water resources [6]. Moreover, socio-economic changes such as changes in land use and weir construction have a direct impact on the hydrological cycle, altering the timing and volume of water uptake and discharge [7]. Population and economic growth are the main factors causing the increased demand for food, the higher standard of living, the changes in food and energy consumption patterns, and the development of agriculture [8]. These changes are related to the constantly growing global demand for water [9,10].

Past research has focused on water footprint analyses, which use various approaches to determine the amount of water required for the production of energy at the level of individual plants, as well as at the regional level [11,12]. As the impact of power plants is usually local and applies at the catchment area level, a higher spatial resolution that allows for greater spatial heterogeneity should be considered in water stress analyses [13,14]. This approach can be found in the papers by Koch and Vögele [15] and by Van Vliet et al. [5], who analysed the impact of potential climate change and changes in water resources on the existing local power plants and other enterprises using the water resources of the catchment area. The research did not predict a reduction in water use in other sectors, which may contribute to the greater water stress and potential water restrictions predicted in the energy sector when water resources are limited [16,17]. This would also have a significant impact on the environment, agriculture, and economy [18,19].

Research by Kubiak-Wójcicka and Machula [2] analysing the Water Stress Index in Poland in the years 1999–2018 showed that the average WSI value was 1566 m³ per citizen. This means that Poland was classified among the countries with low water resources that are vulnerable to water shortages. The seasonal variability of water resources and their unequal distribution across the country are highly significant in Poland. This is due to issues such as variability in precipitation and air temperature. Considering the pressure related to water shortages, it is necessary to take measures to limit water shortages. Moreover, it is important to look for solutions to alleviate water shortages and to look for ways to reuse water. These measures should have a regional character so that they can be best adapted to the conditions in a given area [20].

Conventional power plants are highly dependent on access to water, which plays a crucial role in cooling processes. Under conditions of water shortages and predicted water deficits caused by climate change, the operation of these plants is becoming increasingly challenging. Electricity production and distribution are among the industries with the highest water consumption [21]. The electricity industry is responsible for at least 45% of the total water uptake in most EU (European Union) member states [22]. Water consumption for the energy sector is a serious challenge in the face of climate change, which alters the distribution of precipitation and raises the average temperature in the environment [23]. In recent years, the whole of the EU has faced serious water shortages, limiting the capacity of conventional power plants [15]. Due to climate change, it is expected that periods of water shortage in the EU may become longer; therefore, it is important to understand the impact of water stress on the energy system in Europe [24]. This problem is becoming an essential part of studies on climate change adaptation and alleviation [25]. Studies on the use of water for energy production are highly significant because researchers and policymakers have realised the growing sensitivity of the energy system to water availability [26,27].

Of the conventional sources of power generation, gas-fired power generation is currently the best option in terms of the trade-off between energy security and environmental protection, offering a significant environmental advantage. Analysing the data summarised in

Table 1. Comparison of the performance of a coal and gas-fired power plant.

Parameters		Coal-Fired Power Plant	Gas and Steam Block
Investment costs [28]		larger	smaller
Construction time [28]		longer	shorter
Operating time [28]		longer	shorter
Emissivity of substances g·kWh−1 [29]	SO2	3.2	0.08
	CO2	420	202
	dust	16.4	-
Calorific value [28]	MJ·kg−1	21–29	50
	GJ·m−3	24	35
Combustion process [28]	time	longer	shorter
	Flame temp. °C	2200	2100
Water consumption -median m3·MWh−1 [30]	Tower (cold storage)	2.6	0.75
	Single-pass system	0.95	0.38
	Cooling lake	2.06	0.91

, it is clear that technologies for generating electricity should move towards minimising water consumption. The coal technologies that are currently in use have a high level of water consumption, so gas systems designed in a combined cycle (gas–steam) deserve attention. When making changes to national energy policy, water management cannot be disregarded, especially when considering the progression of climate change and the need to increase restrictions on the emission of harmful substances, such as CO₂, whose elimination would decisively increase water use. As such systems have low SO₂ emissions and virtually no dust emissions, they avoid the need for the use of advanced flue gas cleaning technologies [28,29,30].

As part of the water conservation measures, we would need to review opportunities related to limiting water use in the industrial sector, including limiting the demand for huge amounts of cooling water in the energy industry. In 2023, 72.65% of the energy produced in Poland was produced from fossil fuels and only 27.35% was produced from renewable sources (Figure 1). The ongoing energy transition, aiming to move away from fossil fuels in an economy dominated so strongly by coal, is difficult and requires intermediate measures [31]. The replacement of coal-fired units with gas-fired and gas and steam units, which would initially be fuelled with natural gas and eventually, after modernisation, with hydrogen, would make it possible to complete the process of energy sector modernisation in Poland. In addition to that, each year in Poland, we can observe an annual trend of an increase in the amount of energy produced from Renewable Energy Sources (RES), which accelerates this transition. Owing to the production of energy by prosumers in Poland, the share of RES in 2023 exceeded the output of energy produced from lignite.

After hard coal from the Upper and Lower Silesia Coal Basins, lignite is the second most extracted fossil fuel in Poland. Poland’s total lignite reserves are estimated to be approx. 49 billion tons, of which 14 billion tons were deemed profitable to exploit [32]. In Poland, lignite is used chiefly for energy production. The largest power plants, such as the Turów and Bełchatów power plants, are located in the vicinity of large open-pit mines in Poland’s chief lignite basins: Bełchatów Lignite Basin, Konin Lignite Basin and Turów Lignite Basin [32]. In Wielkopolska, most of the exploited lignite deposits are located in the Eastern part of the region. Some of these deposits have already been fully exploited by Konin and Adamów mines, while coal is still being mined in others. The remaining deposits have small resources. In Konin Basin, lignite is mostly obtained in open-pit mines. The Konin mining and power basin is operated by Konin Mine and two power plants that are owned by Zespół Elektrowni Pątnów Adamów Konin S.A. (ZE PAK S.A.).

The open-pit mining of lignite deposits in the Konin–Turek basin, combined with the extensive mining drains, entails additional external costs that result from the growing threats to various land-use and environmental components in groundwater table depression funnels. In order to prevent these phenomena, measures were proposed to inhibit the further quantitative degradation of water resources in the area. These are expected to contribute to the restoration of the hydrographic network of water courses that have dried out or were moved outside of the area of mining activity, as well as to the flooding of post-mining pits. In post-mining areas, anthropogenic reservoirs are being created. They are filled with water from active drained pits [33] and with water transferred from other catchment areas. It is estimated that these measures will enable the restoration of more than 60 km of rivers and the total surface of water in the flooded reservoirs will cover 3500 ha. The total volume of water in reservoirs will amount to nearly 900 million m³ [34,35,36]. Moreover, it will be possible to create and restore swamps in the area covering 813 ha, which will increase the region’s retention potential [37].

The catchment area of Kiełbaska Duża river, situated in the exploitation area of Adamów lignite mine, is especially exposed to water stress-related problems due to its specific hydrological conditions and the impact of climate change. The reduction in water availability in the catchment area of Kiełbaska Duża river is especially problematic due to the high intensity of water use in the region for industrial as well as agricultural purposes. Forecasts point to a further drop in water level in the region, which may call into question the continued operation of local power plants [38]. Moreover, Eastern Poland is one of the most water-deficient areas in Poland and in Europe.

The energy transition, aimed at reducing the dependency on fossil fuels and minimising environmental impacts, is reshaping energy systems globally [39]. This process involves adopting cleaner, more efficient technologies and integrating renewable energy sources, which often necessitate changes in resource management, particularly water. In regions like Wielkopolska, where water resources are limited, the energy transition is not only an environmental imperative but also a socio-economic challenge, requiring solutions that address both energy and water scarcity. These dual concerns are especially evident in areas with extensive lignite mining and coal-fired power generation, where transitioning to modern technologies has the potential to reduce water demand and environmental degradation [40].

The research in this paper aimed to analyse the impact of the restoration of the natural hydrographic system of the catchment area of Kiełbaska Duża river on the water reserves in the catchment area and on water management in the region, taking the planned investment in power infrastructure into account. The paper presents the prospects and measures to improve the rationality of the use of water resources for energy production in the catchment area, where significant water deficits have been observed and mining operations have been subject to transformation due to lignite reserves running out. The case of moving away from the exploitation of lignite resources, the closure of a former coal-fired power plant, and the implementation of the construction of gas and steam units presented in the article is a model example of energy transition; it provides a change in the approach to water resources and in the search for new solutions to improve the hydrological situation in the basin, which has been subjected to significant anthropogenic transformations, on the one hand, and would take measures to ensure energy security on the other (Figure 2). The research presented here includes an analysis of previous hydrological data, which show that ending lignite mining and gradually restoring natural run-off will have a positive impact, stabilising the hydrological situation in the catchment area. The collected data made it possible to develop hydrological scenarios that take the future reduction in water stress into account when implementing plans to restore the former hydrographic system in the region. The conclusions of the research suggest that implementing new technologies and improving water management in the catchment area would make it possible to limit the negative impact of industrial activity, including that of the energy industry, on water reserves, which is crucial for environmental security in the catchment area.

The challenges in water and energy management are profound and interconnected, with climate change, industrial activities, and socio-economic development exacerbating water scarcity and environmental degradation. This particularly applies to water stress conditions comprising water deficits and increases in water temperature. This situation exemplifies the broader global issue of the need to balance water resource availability with industrial and agricultural demands.

This study provides critical insights into the synergistic effects of energy transitions and sustainable water management. By demonstrating the potential to reduce industrial water demand and restore natural ecosystems, it serves as a model for addressing the du-al challenges of energy modernization and water resource preservation, ensuring long-term environmental and energy security.

2. Methodology and Research Material

2.1. Area of Research

2.1.1. Catchment Area of Kiełbaska Duża and Teleszyna Rivers

The area of research included the catchment areas of Kiełbaska Duża (A = 324 km²) and Teleszyna (A = 317 km²) rivers. Kiełbaska Duża river, labelled with the code PL18334, is located in the central part of Poland, in the east of Wielkopolskie province (source 51°56′19″ N 18°25′27″ E, estuary 51°56′19″ N 18°25′27″ E). The river is 45 km long and is the left-bank tributary of the Warta river (the third largest river in Poland). There is one hydrological station on Kiełbaska Duża river; this is called “Kościelec” and is located 6.95 km along its course. It is controlled by the Institute of Meteorology and Water Management (IMGW–PIB), as shown in Figure 3. The catchment area of Teleszyna river (source 51°44′51″ N 18°39′53″ E, estuary 52°11′51″ N 18°34′18″ E) is an uncontrolled estuary for which the IMGW–PIB does not conduct hydrological measurements. Teleszyna river, which is 30 km long, is also a left-bank tributary of the Warta River.

In geomorphological terms, the analysed catchment areas are located in the Wielkopolsko–Kujawska Lowland, in the mesoregion of the Turek Upland [41]. This is an area of ground moraine and Central Polish glaciation, at a stage of the Warta River with a dense cover of Quaternary formations [42]. The terrain of the catchment area is slightly undulating, sloping to the East towards Kiełbaska Duża river. To the north of Turek, there are hills of the end moraine called the Szadowskie Hills, where the height differences reach 30 m, with absolute heights ranging from 100 to 130 m above sea level. In the region of the planned investment, terrain elevations range between 107 m above sea level in the area of the Kiełbaska Duża river to about 112 m in the area of Adamów Power Plant [43].

The catchment area of Kiełbaska Duża river, along with that of Teleszyna river, is a typically agricultural catchment area (Figure 4), as agricultural lands account for 64.75% of the area (including 42.58% of non-irrigated arable land, 13.49% of grassland, and 8.67% of pasture and other areas associated with cultivation). Moreover, forests account for 23.15% of the catchment area (broadleaf forest 2.89%, coniferous forest 16.24%, and mixed forest and shrub vegetation 4.02%). Built-up areas (5.46%), industrial areas (0.48%), and roads (0.33%) make up a total of 6.27% of the use of the catchment area. Mining-related open-pit areas, accounting for 4.50%, as well as dumping areas and heaps that occupy 0.19% of the catchment area, are also important parts of the area.

As a result of mining operations, new hydrographic elements, including water reservoirs, have emerged in the existing landscape (Figure 3). At the open pit mines in Adamów, Władysławów, and Koźmin, rehabilitation is being carried out in the direction of the water, which results in the emergence of new water reservoirs at the sites of former open pits. For example, once coal mining ceases at the Adamów open pit mine, approximately 607.9 ha of land will be left for rehabilitation. As the mining operations cease and the lignite mine is closed down, the Głowy, Koźmin, Koźmin Final, and Władysławów reservoirs will be added to the existing Janiszew, Przykona, and Bogdałów reservoirs. The mine is designing two final reservoirs, which will be the largest: Adamów Centralny, Adamów Pośredni, and Adamów Końcowy. The latter will have a surface area of more than 300 ha and depth of up to 40 m. It will take several years to fill. The remaining reservoirs should fill up in a few years. Altogether, the reservoirs established on the territory of Adamów lignite mine will hold nearly 200 million m³ of water, which is in high demand in the region [44]. The cost of this rehabilitation will reach several hundred million zlotys.

The Koźmin and Głowy reservoirs, like the Przykona and Janiszew reservoirs, will be shallow reservoirs of a few meters deep. Their basin will be built during the process of internal dumping. The final reservoirs will be created once the mining of coal has ceased, following the final excavation of the open pit, which will be unfilled with caprock (due to the absence of earth masses for its liquidation). The bottom of the reservoir will consist of the thill of the open pit, while the slopes of the basin will consist of the slopes of the pit [45].

Figure 4. Map of the catchment area of Kiełbaska Duża river with catchment area borders and forms of use–land cover, according to CORINE Land Cover [46].

Figure 4. Map of the catchment area of Kiełbaska Duża river with catchment area borders and forms of use–land cover, according to CORINE Land Cover [46].

The analysis of annual precipitation totals showed that in the years 1960–2021, average precipitation amounted to 503 mm (Figure 5). In the period 1960–2021, there were 20 dry years (including 7 very dry years) with the total precipitation accounting for 50 to 75% of the average precipitation for the period; 20 wet years (including 4 very wet years) where total precipitation accounted for from 111 to 150% of the average; and 22 years with the annual precipitation approximating the average for the period.

2.1.2. Adamów Power Plant and the Planned Gas and Steam Unit

Adamów Power Plant was built in the years 1960–1967 in the vicinity of the town of Turek, on the left bank of Kiełbaska Duża river. It consists of five turbine sets (120 MW each) with a total capacity of 600 MW. It was fuelled with lignite obtained in the nearby open-pit lignite mines and, as well as generating power, it also supplied heat to the town of Turek and the nearby manufacturing plants, as well as providing steam to the Zakłady Przemysłu Jedwabniczego “Miranda” (“Miranda” Silk Plant) in Turek. The power plant was one of the four power plants comprising ZE PAK S.A. In 2010, it was decided that the power plant had to be closed down due to the high cost of adapting to the pollutant emission standards, which coincided with the depletion of coal deposits in Adamów Mine [48]. The liquidation of the coal-fired power plant started in January 2018 when the final unit was eventually switched off and preparations for the dismantling of the plant began. The final part of the power plant was dismantled on 9 September 2022. The area was tidied up, cleared, and prepared for a future investment project [34].

The proposed location for a new gas and steam unit with a capacity of 600 MWe is the site previously occupied by the coal-fired power plant Adamów, which has since been decommissioned and dismantled (Figure 6). The plant belonged to ZE PAK S.A. The facilities of the gas and steam unit will be located in the central part of the closed-down power plant [49]. Due to its location and the fact that the area was recently used for industrial purposes, the planned investment project will have a relatively small impact on the environment. The existing infrastructure, including, for example, water intake from Kiełbaska Duża river, an industrial wastewater discharge site, and the extensive infrastructure required for receiving electricity, significantly limits the amount of work and the costs required, as well as the time needed to launch the facility. Taking into account the absence of equipment associated with coal-fired units, such as a coal depot, a sidetrack for the unloading of coal, or electrofilters, as well as the decisively smaller size of the heat recovery boiler, the planned investment will be located in a significantly limited area. This will make it possible to expand the facility on a plot of land of the same size as the coal-fired power plant without having to reconvert the land adjacent to the planned investment.

Apart from the most important power generation installation, which relies on gas and steam technology, based on a gas turbine with a recovery boiler and a condensing tank-cooled steam turbine, the concept of the gas and steam unit assumes that the other elements of the system will include, for example, natural gas preparation, preheating, a compression station, and a wet mechanical draft cooling tower (Figure 7). For the proper operation of the power plant, a water source and a water treatment plant with a water demineralisation station are important to ensure the necessary water parameters are present for processing purposes. Its location, along with the water storage, is planned to be in the water treatment station building (Figure 8, no. 3). The water will be drawn from the Kiełbaska Duża river and will be supplied to the plant via an existing pipeline (Figure 8, no. 4 and 6). The equalising tanks located next to the pipeline will ensure access to the needed resource in times of increased demand or water shortages.

The overall efficiency of the planned unit exceeds 85% compared to the 45–47% efficiency of the coal-fired unit. This is possible due to the technical measures applied, which include electricity production (61%) and heat recovery (24%) at the cooling stage. The combusted fuel mixture, consisting of natural gas and highly enriched in oxygen, enters the combustion chamber via compressors. At the first stage of decompression, the resulting exhausts are used to power the gas turbine. Later, thermal energy is successively converted into mechanical energy and electricity. Unconverted thermal energy will be recovered in the recovery water boiler, where it will be used to generate overheated steam that powers a steam turbine to produce electricity.

As mentioned before, raw water for use by the gas and steam unit will be supplied from Kiełbaska Duża river. Raw water will be drawn by an upgraded system for the uptake (pumping station on Kiełbaska Duża river) and will be subsequently distributed via newly designed systems to individual facilities/installations in the gas and steam unit. The replenishment of low water flows in Kiełbaska Duża and Teleszyna rivers will be accomplished, as before, by pumping water from the Jeziorsko reservoir on the Warta river. With the above-mentioned measures in mind, on 12 December 2011, the Marshal of Łódzkie province issued the permit required under the Water Management Act to authorise ZE PAK S.A. to make specific use of this water by transferring water from Warta river, through the Jeziorsko reservoir, to the Kiełbaska Duża river, and to dam the waters of Teleszyna river in the Żeronice reservoir. Within the scope of the granted permit, the specific uses of water consist of the following: the transfer of water from Warta river and the Jeziorsko reservoir, through the Miłkowice II pumping station (located in Ostrów Warcki, 0 + 603 km of the side dam on the Teleszyna river), via a covered canal to Wilczków node, via Teleszyna river to Przykona Node, and via an open canal to Kiełbaska Duża river, in an amount ranging from 0.4 m³ s⁻¹ to max 0.8 m³ s⁻¹; the damming and retention of the waters of Teleszyna river in the Żeronice reservoir with a discharge weir located 41 + 150 km of Teleszyna Górna river (19 + 500 km of the transfer route), provided that the inviolable flow of Teleszyna river (below Żeronice reservoir)—Qn = 0.120 m³ s⁻¹—remains intact.

2.2. Methodology

The boundaries of the catchment area of Kiełbaska Duża and Teleszyna rivers were drawn using the Map of the Hydrographic Division of Poland (scale 1:10,000). The hydrographic location was determined using the geodatabase of the second update of the River Basin Management Plans (II aRBMPs), obtained from the National Water Holding Polish Waters, National Water Management Authority [52]. The catchment area structure was analysed using the CORINE Land Cover [46] inventory from the Chief Inspectorate of Environmental Protection (GIOŚ). The meteorological conditions were described using annual precipitation totals from 1960 to 2021, obtained from the precipitation station in Kalisz, IMGW–PIB. Humidity characteristics were prepared according to Kaczorowska’s (1962) [53] methodology.

Hydrological characteristics were derived using data on the daily flows of the Kiełbaska Duża river in the Kościelec profile from 1956 to 2023, obtained from the IMGW–PIB. Water stress calculations were based on daily average flows. Water stress was defined as the daily flow of the Kiełbaska Duża below the maximum water demand of the Adamów Power Plant. The water stress criterion was set at 0.347 m³ s⁻¹. The technical characteristics of the gas and steam unit were prepared using Kaleta and Śluzar [54].

The open-pit lignite mining operations were carried out until 2018, and the power plant in operation continues to affect the hydrological characteristics of the Kiełbaska Duża and Teleszyna catchment area. Deep mining dewatering has triggered the formation of a cone of depression, which has decreased surface and groundwater levels in the affected areas [42]. The water derived from the pumping out of the open pits was fed into the Kiełbaska Duża. In 2021, the last tonne of coal was extracted from the last operating Adamów open pit. The discontinuation of lignite mining operations and the commencement of intensive land rehabilitation contributed to a change in the hydrographic conditions. The groundwater level is gradually rising, while the pumping and injection of mine water into the catchment area of the Kiełbaska Duża has ceased. Accordingly, Reference [55] presented scenarios describing the current and projected conditions in the Teleszyna and Kiełbaska Duża catchment areas from the perspective of restoring the original groundwater resources. These scenarios were used to conduct detailed analyses of the recreation of the hydrographic network and the hydrological changes in the catchment.

2.3. Hydrological Scenarios

Hydrological analyses were used to forecast changes in the Teleszyna and Kiełbaska Duża catchment areas. Data were compiled for three calculation scenarios covering the current situation (Scenario 0—S0) and the projected situation [55]. The scenarios covering the projected situation attempt to estimate the hydrological characteristics over the period immediately following the planned changes to the hydrographic network and water management (Scenario 1—S1) and over a further time horizon (Scenario 2—S2). This scenario predicts a stabilisation of hydrological conditions, the disappearance of the impact of the current water management associated with the open-pit operations, and a gradual return to natural run-off conditions in both catchments. Detailed descriptions of the selected scenarios read as follows:

2.3.1. Scenario 0—Current Situation

This covers the current hydrographic system and water management. The main objectives include diverting water from the upper Teleszyna to the Kiełbaska Duża via the Teleszyna—Kiełbaska canal, pumping water from the open pits into various watercourses, with gravity feeding the Adamów Pośredni and Adamów Końcowy reservoirs from the Przykona reservoir.

2.3.2. Scenario 1—Planned Changes

Scenario I defines the water abstraction operation for the planned gas and steam units and water allocation at the Teleszyna–Kiełbaska Duża node for the replenishment of water resources in the middle Teleszyna in a way that supports the filling of water reservoirs after the Adamów Pośredni and Adamów Końcowy excavations.

It assumes the reintroduction of a natural hydrographic system after the cessation of mining operations and the closure of the Turek power plant. The main objectives include diverting water from the upper Teleszyna to the middle Teleszyna and completing all pumping from the open pits. The scenario defines the situation that is to be expected in the near-term after completing the filling process. This includes water abstraction for the planned gas-fired power plant’s operation through pumping water into the upper Teleszyna channel via the Miłkowice II pumping station and water distribution at the Teleszyna–Kiełbaska node. It is assumed that the pumping into the upper Teleszyna channel will be carried out during periods of a shortage of run-off from the Kiełbaska Duża river catchment. A pumping rate of 0.800 m³ s⁻¹ was assumed for both flow options: AALF (Average of the Annual Low Flow) and AMAF (Average of the Mean Annual Flow). It is also assumed that a gradual normalisation of surface water conditions within both catchments will be noticeable. The scenario assumes that the middle Teleszyna and Struga Janiszewska sections will not experience flow loss due to infiltration. At the same time, it is assumed that the supply of the lower Teleszyna section from the Koźmin reservoir will not be pursued.

2.3.3. Scenario 2—Long-Term Projections

This concerns the further stabilisation of hydrological conditions after the restoration of natural run-off and the cessation of lignite mining. The main objectives are similar to Scenario 1 but involve the complete stabilisation of natural run-off. It should be noted that the time horizon for the implementation of S2 is impossible to determine due to the variability of hydrometeorological conditions.

A simulation using rainfall-to-run-off transformation models determined hypothetical hydrographs with a specific culminating flow value. For the calculations, the Soil Conservation Service—Curve Number (SCS-CN) method for sub-catchments was applied. The calculations were performed using the HECGeo-HMS add-on of ArcGIS. A modified model version was used to determine the maximum flows. Calculations were performed for each characteristic flow and three scenarios were presented for the conditions of the hydrographic network and the water management of the catchment. The results were related to the basic computational profiles of the Kiełbaska Duża and Teleszyna catchment areas (Figure 9).

3. Results

3.1. Water Stress Analysis in the Catchment Area of the Kiełbaska Duża

Between 1956 and 2023, the Kiełbaska Duża catchment underwent a number of changes in the hydrography of the river network, open-pit mining, and water management related to the operation of the Adamów coal-fired power plant and the Przykona Reservoir. These changes could have significantly influenced the flow pattern (Figure 10), indicating genetic heterogeneity in the measurement sequence recorded at the Kościelec gauging station. A statistical test of the homogeneity of a sequence of flows for hydrological years 1956–2023 was carried out, among other things. Calculations were performed using the Mann–Kendall test to check for the non-existence of a monotonic trend. The lowest annual flow values were analysed, and the test value obtained, 0.0001, confirms the sequence’s statistical heterogeneity.

Between 1955 and 1966, before the start of the Adamów Power Plant operation, the AMAF for the Kościelec profile was 1.205 m³ s⁻¹. After the construction of the Adamów Power Plant, much of the water from the dewatering of the open pits was channelled through ditch channels draining into the Struga Janiszewska, which is the right tributary of the Kiełbaska Duża. Therefore, the average flow in the Kiełbaska Duża between 1966 and 2018 was 2.635 m³ s⁻¹. Thus, the dewatering of the open pits had a significant impact on the formation of flows in the downstream section of the Kiełbaska Duża. In January 2018, the operation of the Adamów Power Plant’s coal units was terminated. In the following years, ending in 2021, the operation of the open pits was also terminated, reducing the discharge of water from the pit drain. The average flow discharged into the Kiełbaska Duża from lignite open pits, according to ZE PAK S.A. Konin data, should be estimated at between 0.500 and 0.940 m³ s⁻¹. An analysis of the results of water resources monitoring in the Kiełbaska Duża river basin (including reports commissioned by ZE PAK S.A. Konin) showed that, between 2019 and 2023, the water resources in the basin were reduced; in such cases, resources should be supplemented by water transfer from the Jeziorsko reservoir to ensure optimum conditions for the operation of the gas and steam unit.

An analysis of the daily mean flows between 2019 and 2023 highlights 992 days with water stress (Figure 11). This amounts to an average of 198 days, or 54% of the average hydrological year. Assuming that water stress involves water pumping from the Jeziorsko reservoir in an amount corresponding to the demand of the gas and steam unit (0.347 m³ s⁻¹), the total volume of pumped water in an average hydrological year should amount to 5.95 million m³. Converting the determined volume into the mean annual flow, the result is 0.189 m³ s⁻¹ to be abstracted from the Jeziorsko reservoir.

It is anticipated that the estimated periods of water stress resulting from low flows in the Kiełbaska Duża are not a fixed characteristic over time and may change due to, among other things, planned water management aimed at normalising water conditions in the Kiełbaska Duża and Teleszyna catchments. Due to the completion of the open pit dewatering and rehabilitation tasks, including filling the pits, the impact of the groundwater cone of depression is forecast to disappear in the long term and gradually return to natural run-off in the Kiełbaska Duża and Teleszyna catchment areas.

3.2. Analysis of Hydrological Scenario Results

Hydrological analyses have shown that the cessation of lignite mining and the restoration of the natural hydrographic system will significantly impact the hydrological characteristics of the Kiełbaska Duża and Teleszyna catchments; notably, the end of pumping and the restoration of natural run-off will stabilise hydrological conditions. These results are important for planning future water management and environmental activities in the region.

Comparing the flow values from the model computations for Scenario 0 for AALF and AMAF (

Table 2. Comparison of characteristic flows of the Kiełbaska Duża in the Kościelec profile and those computed by the simulation model.

Scenario	Flow	Time Period	Measurements	Model	Absolute Difference	Relative Difference
			[m3 s−1]	[m3 s−1]	[m3 s−1]	[%]
Scenario 0	AALF	2019–2023	0.180	0.187	0.007	3.9
	AMAF		0.980	0.970	−0.010	−1.1

), it should be stated that the results coincide with the characteristics determined for the hydrological station in Kościelce, which confirms the correctness of the adopted methodology and computational assumptions [56].

Drawing on a correctly defined catchment model, all scenarios were modelled.

Table 3. Summary of AALF and AMAF for Scenarios 0, 1, and 2 in the basic computational profiles [56].

No Cross-Sections	Computational Profile Name	River	AALF [m3 s−1]			AMAF [m3 s−1]
			S0	S1	S2	S0	S1	S2
1	Kiełbaska—locality Cichów—road bridge	Kiełbaska Dolna	0.180	0.164	0.185	0.934	0.898	1.307
2	Kiełbaska weir power plant	Kiełbaska Środkowa	0.086	0.375	0.374	0.395	0.542	0.542
3	Estuary of Struga Janiszewska	Struga Janiszewska	0.000	0.000	0.022	0.014	0.135	0.544
4	Estuary of the Northeastern Ditch	North-Eastern Ditch	0.000	0.000	0.000	0.001	0.001	0.001
5	Teleszyna Sarbice weir	Teleszyna	0.002	0.002	0.036	0.020	0.020	0.180
6	Estuary of Teleszyna	Teleszyna	0.198	0.198	0.052	0.287	0.287	0.267
7	Teleszyna m. Przykona—DK 72 bridge	Teleszyna	0.061	0.861	0.661	0.282	1.082	0.882
8	Teleszyna tributary to reservoir Przykona	Teleszyna	0.003	0.514	–	0.026	0.679	–

shows the analysis results, referring to the basic computational profiles in the Kiełbaska Duża and Teleszyna catchments.

The results obtained in Scenario 1 indicate (Table 3) that, given the assumptions concerning natural flow from the catchment area of Teleszyna and Kiełbaska rivers described above, the water resources are sufficient to simultaneously cover the water demand for the operation of the planned gas-fired power plant and for the planned filling of the Adamów Pośredni and Adamów Końcowy reservoirs. The completed filling of the Adamów Pośredni and Adamów Końcowy reservoirs is the boundary condition for the process of normalising water relations in the central part of the catchment area of the Teleszyna and Kiełbaska rivers. It should be expected that the complete filling of the reservoirs and the permanent stablisation of the groundwater table that remains in hydraulic contact with the reservoirs will translate directly to the normalisation of water relations observed in the network of surface channels. The exact date of the permanent filling of the two reservoirs is difficult to determine with precision due to the considerable uncertainty of the elements that make up their water balance. According to the provisions of Scenario 1, it can be expected that the process of filling the reservoirs will be completed in no more than ten years.

According to Scenario 2, as the filling of the Adamów Pośredni and Adamów Końcowy reservoirs has been completed, water uptake for the purposes of the operation of the planned steam and gas power plant will be carried out by pumping water to the channel of the upper Teleszyna river and by separating water at the Teleszyna—Kiełbaska node. In periods of insufficient natural discharge from the catchment area of the Teleszyna and Kiełbaska rivers, pumping will be carried out at an average level of 0.600 m³ s⁻¹. Due to the discontinuation of the operations of the lignite mine, hydrological conditions will become normalised. The groundwater table will stabilise permanently, which will translate into a gradual normalisation of the water relations observed in the network of surface channels in the area in question. The conditions of discharge in the analysed catchment areas will resemble the conditions that occur naturally in these catchment areas. Taking the results of the modelling into account, we need to indicate, for example, the cross-section of the weir on Kiełbaska Duża river containing the planned power plant, where AALF flows are expected to increase from 0.086 m³ s⁻¹ for S0 to 0.374 m³ s⁻¹ for S2, and from 0.395 m³ s⁻¹ for S0 to 0.542 m³ s⁻¹ for S2 for AMAF. Similarly, in the section of central Teleszyna and Struga Janiszewska, there will be no decline in flow due to infiltration, but rather an increase in AALF flows is expected, from 0.00 m³ s⁻¹ for S0 to 0.022 m³ s⁻¹ for S2 and from 0.014 m³ s⁻¹ for S0 to 0.544 m³ s⁻¹ for S2, in the case of AMAF.

3.3. Comparison of a Conventional Lignite-Fired Power Plant and a Steam and Gas Turbine Power Plant

The gas and steam unit with a capacity of 600 MWe, fired by natural gas, will operate with a gross electrical efficiency of c.a. 61%. This is a technically mature solution with the lowest impact on specific environmental components among the existing fossil fuel technologies. The new power unit will be equipped with a gas turbine. The decision to implement the variant of the project proposed by the Investor is motivated by the following considerations:

• The selected variant complies with the objectives of Poland’s Energy Policy until 2040. One of the main objectives of the Policy is to improve the security of fuel and energy supplies. The energy policy focuses on the rational and efficient management of the fuel reserves available in the country;
• The expected impact of the selected variant on specific components of the environment, especially on air quality, will be smaller than the impact of a conventional lignite-fired unit of the same capacity.

The proposed technology has lower emissions than a similar unit using lignite technology. The smallest difference can be observed for nitrogen oxides (c.a. 9%); at the assumed capacity, this unit produces nearly 76 Mg NO_x less than a coal-fired unit per year. The differences for CO₂ and SO₂ emissions are even more significant and amount to 47% and 68%, respectively. In the case of CO₂, we reduce emissions by nearly 1,500,000 Mg, which corresponds to over 635 m³ of petrol.

The technology that uses gas and steam units for electricity generation has more environmentally friendly parameters than coal-fired units. The total efficiency of the planned unit (electric and thermal) exceeds 85%, compared to 45–47% in the case of the former coal-fired unit. Owing to the greater efficiency, there will be a reduction in pollutants released into the atmosphere. Moreover, the gas and steam unit will have a lower failure rate in comparison to the coal-fired unit, while maintaining high flexibility with regard to the operating conditions and availability.

Due to the type of fuel used in gas-fired units, there are no combustion wastes and no accompanying pollutants associated with the transportation and unloading of coal. The gas and steam unit is also distinguished by the absence of problematic wastewater originating from the wastewater treatment plant and from the extinguishing of the furnace. Wastewater from the gas and steam unit will have the same quality parameters as wastewater from coal-fired units (due to the water demineralisation process); however, their quantity will be significantly smaller (2,147,076 m³∙y⁻¹ from a lignite-fired power plant and 1,352,313 m³∙y⁻¹ from the gas and steam unit). Therefore, the pollutant load discharged from the gas and steam unit will be smaller than the pollutant load discharged from a coal-fired power plant. Given the above, the construction of a gas and steam unit at the site of the former coal-fired power plant could reduce the negative impact on the environment, including water (reducing the load of pollutants discharged into the water).

4. Discussion

One of the most serious threats to human societies and an obstacle to sustainable development is water scarcity resulting from population growth and economic growth [57]. Water is estimated to become the most strategic resource in the coming decades [58]. In many countries, the current and future electricity sector is and will continue to be highly dependent on secure access to water resources, which are essential for the proper operation of power plants. This applies to hydropower plants and plants where water is used for cooling, i.e., most thermal power plants, regardless of whether they are powered by coal, oil, gas, biomass, or nuclear power [26,27]. Globally, a disparity can be seen between the demand for freshwater and its available supply [59]. Power plants that produce electricity use the greatest proportion of water in the US [60]. An analysis of the amount of water used in China for cooling power generation plants revealed the total to be 3.5 km³ of water. This accounts for 11% of China’s total industrial water consumption, of which 84% is attributed to closed-cycle cooling power plants. The average water consumption intensity of power plants in China was 1.15 dm³∙kWh⁻¹. Consumption in other countries reaches 1.55 dm³∙kWh⁻¹ in Spain, 1.7–2.00 dm³∙kWh⁻¹ in the EU, 1.8 dm³∙kWh⁻¹ in the USA, and an average of 1.75 dm³∙kWh⁻¹ worldwide [61].

The Konin Basin and the local energy sector are located in the area with the greatest deficits in water resources in Poland. An analysis of Poland’s hydrological and meteorological characteristics indicates that the area in question has the lowest annual precipitation, which, on average, does not exceed 550 mm∙y⁻¹. The average annual air temperature is around 9.2 °C [62]. As a result, water shortages, measured by the difference between precipitation and annual potential evaporation, are around 200 mm. Likewise, successive extreme weather events, such as increasingly frequent, alternating, several-week droughts and subsequent heavy rainfall, contribute to reductions in the infiltration and recharge of groundwater and lakes [63].

Notably, the average specific discharge in Poland is 5.2 dm³∙s⁻¹·km⁻². In the Vistula basin, it reaches 5.1 dm³∙s⁻¹·km⁻²; in the Oder basin, 4.7 dm³∙s⁻¹·km⁻²; and in the Warta basin, only 3.7 dm³∙s⁻¹·km⁻². In comparison, the specific discharge from the study area varies between 2.0 and 3.0 dm³∙s⁻¹·km⁻², with catchments in the eastern part of the region, including the area around Turek in extreme cases, even becoming closed basins [63]. As a result of the overlapping of these impacts, a significant portion of the catchment area of the Kiełbaska Duża and Teleszyna rivers has seen a substantial reduction in surface and groundwater levels, evident in the loss of flow in watercourses, the drying up of wetlands, and the lack of water in wells. These phenomena are particularly pronounced in the area containing the lignite open pits, where the impact of a cone of depression is also observed. It is also worth emphasising that the current hydrological situation results from the rapid occurrence of several adverse weather phenomena in Poland and from the climatic changes that we can also observe in other parts of the world. Hydrological drought, the region’s biggest challenge, reached its maximum extent and intensity in 2015.

Global warming is also causing more frequent heat waves and droughts in Europe, which, in turn, are affecting electricity production. These changes have a more significant impact on southern European countries (including Italy, Spain, and Portugal) than on northern (Scandinavian) countries. From this perspective, EU energy policy decisions should consider such geographical disparities and promote the transition to renewable energy accordingly [64]. The European energy sector is currently unsustainable in terms of water consumption. Power units using river water for cooling are undergoing negative changes in all countries. Hence, it is essential to increase the share of renewable energy production [65,66].

In a situation of disproportionate water resource availability, interbasin transfers are the only solution that allow for adequate water yield guarantees. The creation of appropriate bodies with representatives from multiple institutions, sectors, and mediators to resolve social conflicts is crucial in such water transfer projects [67]. Due to the moderate water resources available in the south and dry north, more than 20 large-scale physical water transfer projects, with a total length of more than 7200 km, have been developed in China, including the largest in the world, the South–North Water Transfer Project (SNWTP) [68,69]. The SNWTP includes three routes that will eventually transfer 44.8 Gm³ of water annually from the Yangtze river basin to the Huang–Huai–Hai river basin. Another example of this solution is the river diversion project in Brazil. This aimed to generate hydroelectric power for the growing city of Rio de Janeiro. It involved constructing a series of 300 m high-hydroelectric power plants on the Atlantic side of the Sierra do Mar, with a capacity of 1407 MW. This project involved diverting 180 m³∙s⁻¹ of water from the catchment of the Paraiba do Sul (about two-thirds of the average river flow) to the Guandu River [70,71]. A similar approach was used for a large-scale Brazilian project, the Sao Francisco river transbasin diversion [67].

Interbasin transfers are also quite common in Poland. One example of a water transfer canal is the Ślesiński Canal, which, together with other hydrotechnical structures, provides cooling for the Pątnów–Konin power plant complex. The power plant’s cooling system, which forms the so-called small cycle, includes the following lakes: Licheńskie, Wąsowskie, and Pątnowskie. The water abstraction used for cooling the power plant equipment averaged 561,000,000 m³ annually between 2010 and 2014. The huge demand for water from the lakes that comprise the canal’s summit level means periodic shortages may occur between May and September. These are supplemented by water diverted from the Warta via the Pątnów and Morzysław pumping stations [72].

In the Kiełbaska Duża catchment, a system was developed to use the surface water resources of neighbouring catchments (water transfer from the Warta catchment through the Teleszyna to the Kiełbaska catchment). Although the calculations showed that, with the defined assumptions of the S2 scenario, the water resources in the Kiełbaska Duża channel are sufficient to cover the water needs of the planned gas and steam units, taking into account the random variability in the water resources, the project investor assumed the possibility of pumping water from the Jeziorsko reservoir. This solution was previously in place during the operation of the old power station. The entire infrastructure in the catchment areas of the Kiełbaska Duża and Teleszyna rivers (canals, reservoirs, and pumping stations) was prepared in advance. The maximum amount of water pumped between 2006 and 2023 was approximately 6.8 hm³ in 2009 (Figure 12). The annual average between 2006 and 2017 was approximately 4 hm³ of water, representing an average recharge of 0.13 m³∙s⁻¹ (the permit required by the Water Law for maximum water recharge is 0.8 m³∙s⁻¹). With the closure of the power plant, water pumping virtually stopped. Only in 2023 did the pumping of approximately 300,000 m³ of water begin, related to the recharge of the Kiełbaska Duża catchment area and the flooding of the closed open pits. The launch of gas and steam units will also initially be associated with an additional supply acquired through pumping, especially as the flooding of the open pits will be continuous.

Water resources play a key role in the electricity sector. In some regions, such as the Konin Lignite Basin, limited rainfall and an increasing water demand exacerbate the problem of water availability [72]. An additional adverse factor is climate change, which is causing more frequent droughts and heat waves, affecting the energy production capacity of conventional power plants. The adaptation and transformation of the energy sector to better manage water are becoming necessary to ensure the sustainability of production [26]. This often requires special solutions, such as storing water in reservoirs and transferring it to create safe reserves to offset periodic shortages of available water in catchment areas. The best example of this is the power supply system for the Adamów power plant.

In December 2019, a new strategy for the development of Europe was presented, called the European Green Deal (EEO). This is a policy initiative to achieve climate neutrality by the European economy by 2050. Poland is ranked 41st in the world on the 2020 electricity systems ranking list, and 26th (penultimate before Cyprus) among EU Member States [73]. Therefore, the energy transition in our country will be a time- and capital-intensive process. The planned construction of the steam–gas unit fits perfectly into the development strategy of the European Green Deal, C02 emissions and will contribute to the improvement of the electricity systems in Poland.

The transition from coal-fired to gas and steam units, as is occurring at the Adamów power plant, exemplifies the efforts to reduce emissions, minimise water consumption, and improve efficiency. This shift reflects broader energy transition goals: reducing environmental impacts, adapting to changing climatic and hydrological conditions, and fostering more sustainable energy systems [39]. Complementary measures, such as restoring natural hydrographic systems and developing retention reservoirs, address water stress while enhancing regional resilience to climate change. These initiatives illustrate how the energy transition extends beyond technological upgrades, integrating environmental and resource considerations [40].

By stabilising hydrological cycles and reducing industrial pressures on natural resources, energy transition strategies provide a blueprint for fostering environmental and energy security [74]. This holistic approach is particularly significant for regions worldwide that are grappling with the dual challenges of water scarcity and the need for a sustainable energy transformation [75].

5. Conclusions

The catchment area of the Kiełbaska Duża and Teleszyna rivers, located near the Adamów lignite mine operations, is experiencing significant challenges due to water scarcity, caused, among other things, by intensive water consumption by industry and agriculture. Declining groundwater levels could affect the stability of the energy infrastructure, which is vital to the country’s energy security. The research presented here includes an analysis of the hydrological historical data, which show that ending lignite mining and gradually restoring natural run-off will have a positive impact on stabilising the hydrological situation in the catchment area and lowering the risk of water stress. The study provides valuable hydrological and meteorological data, which are crucial for understanding the impact of open-pit lignite mining on the catchment areas of the Kiełbaska Duża and Teleszyna. The adopted calculation methods and detailed calculation scenarios make it possible to forecast hydrological changes and plan appropriate water management measures accurately. The results of hydrometric measurements, environmental monitoring in the Kiełbaska Duża catchment area, other work commissioned by ZE PAK S.A. Konin, and the available compilations of hydrometric measurements for 2019–2023 indicate scarcity of the catchment’s own resources. Water transfer from the Jeziorsko reservoir should supplement these resources to ensure an adequate supply of water to the gas and steam units.

The ongoing modernisation of the Adamów power plant exemplifies the intersection between energy transition and water resource management. By replacing outdated lignite-fired units with gas and steam technologies, this transformation aligns with broader energy transition goals while addressing the pressing issue of water scarcity. The transition highlights the need for a holistic approach, integrating technological advancements with environmental restoration efforts to ensure energy and hydrological security in a region historically impacted by industrial activity.

Introducing more modern solutions, such as gas and steam units with higher efficiency, lower emissions, and a lower water intake compared to coal-fired units, represents an expected transformation of the power plant in a region highly impacted by mining activities. The analyses also indicate the need to continue with water management measures. Studies have shown that the abandonment of lignite mining will reduce the need to pump water from the Jeziorsko reservoir, which will significantly affect the local water balance. Taking into account the modelling results, the situation should improve after the groundwater levels are restored due to the rehabilitation of the Adamów open pit. The conclusions of the research suggest that introducing new technologies and improving water resource management can reduce the negative impact of industrial activities in the catchment, which is crucial for the environmental and energy security of the region. The main results of the work can be summarised in the following points:

• Water stress in the Kiełbaska Duża river basin occurs for about 54% of the hydrological year;
• To reduce the water deficit, it is necessary to use inter-basin water transfers using pumping stations with a flow rate of 0.347 m³/s;
• The annual water demand will be 5.95 million m³ with water being transferred from the Jeziorska reservoir on the Warta river;
• Restoring the natural courses of the Kiełbaska Duża and Teleszyna rivers will contribute to the improvement in the hydrological situation;
• There is potential to build retention reservoirs in former mining excavations with a total capacity of 900 million m³ and an area of 3500 ha was identified;
• The modernisation of power units and their conversion to gas–steam units will reduce water consumption and increase energy efficiency;
• Ending the exploitation of lignite and gradually restoring natural water circulation in the catchment area will have a positive impact on the stabilisation of the hydrological cycle;
• The actions being taken are a model example of the synergy of energy and hydrotechnical transformation.

Studies have shown the need for mutual and close cooperation between the energy sector and water management administration units in catchments. In many cases, hydrotechnical investments are necessary, which will allow for the necessary guarantees regarding water supply in water stress conditions to be obtained. Cooperation with the scientific community is also needed here to allow for in-depth studies and research to be conducted and the most optimal solutions to be found as a result. The situation of climate challenges and challenges related to energy transformation raises serious challenges that require responsible consideration and making decisive and accurate decisions.