Poland’s high voltage transmission network could witness investments worth PLN14 billion in the coming decade. This is to be viewed in the context of around 17 per cent growth in electricity demand expected by the country in 2030. Besides the essential capacity augmentation, the investment outlook for the sector emphasises renewable energy and energy exchanges, both of which hinge on grid connectivity.

Polskie Sieci Elektroenergetyczne (PSE) Operator controls and operates the high voltage transmission network of Poland through five branches in Warsaw, Bydgoszcz, Katowice, Radom and Poznan. Established in 2004, the transmission system operator (TSO) is responsible for ensuring the grid’s synchronous operation with interconnected European power systems, planning and providing for power transfer capacity for cross-border energy exchange, and creating infrastructure for the domestic bulk power market. It is wholly owned by the Polish government through the Ministry of Economy.

Growth in transmission network

As of December 31, 2020, Poland’s high voltage transmission grid comprised 281 lines,  totalling a length of 15,518 km, a transformer capacity of 57,533 MVA, and 109 substations. Of the total transmission lines, one 114-km line operates at 750 kV; 111 lines, totalling a length of 7,822 km, operate at 400 kV; 169 lines, totalling a length of 7,380 km, operate at 220 kV; and the remaining are at the 110 kV and 450 kV levels.

There are 12 major transmission lines connecting Poland’s power system with the networks of neighbouring countries including Sweden, the Czech Republic, Slovakia, Belarus, Ukraine and Germany. This includes the 254-km, 450 kV direct current (DC) underground connection with Sweden. Half of this line length is owned by Poland’s TSO.

 2015201620172018 2019 2020 
Line length (km) 14,268 14,325 14,393 14,897 15,024 15,518
450 kV HVDC USC127127127127127127
750 kV AC OHL114114114114114114
400 kV AC OHL5,9846,1396,3266,8267,1357,822
220 kV AC OHL7,9717,8737,7557,7557,5737,380
110 kV AC OHL727271757575
Transformer capacity (MVA) 51,776 54,27856,77956,320 57,510 57,533
No. of substations 105 106106106 107 109
Table 1: Growth in transmission network
Note: HVDC – high voltage direct current; USC – undersea cable; OHL – overhead line
Source: Polskie Sieci Elektroenergetyczne S.A. (PSE); Global Transmission Report

Financial and operational indicators

The financial performance of the TSO has been fairly sustainable and profitable. The company’s net sales grew at a compound annual growth rate (CAGR) of 4.54 per cent, from PLN7,624 million in 2015 to PLN9,106 million in 2019.

PSE’s net profit has shown an unsteady pattern in the past few years, and it declined marginally from PLN755 million in 2015 to PLN729 million in 2019. Correspondingly, an unsteady trend was also witnessed in operating expenditure throughout the period between 2015 and 2019, and it increased considerably from PLN6,812 million in 2015 to PLN8,266 million in 2019, registering a CAGR of 4.96 per cent.

There was a sudden rise in the capex in 2018 as the TSO allocated funds to implement several projects worth PLN2 billion in the Mazowsze region. The company started construction of a 51-km-long line to link three other high voltage (400 kV) lines, namely, the Kozienice–Siedlce, Siedlce–Stanislawow and Stanislawow–Narew lines. As part of the next stage, PSE also plans to upgrade the Kozienice–Milosna line and replace 30-metre poles with modern, 60-metre poles. In 2019, PSE incurred PLN1,513.3 million on the construction, expansion and upgrade of electrical substations and power lines.

Net sales7,624  8,144  8,887  10,097  9,106   NA  
Net profit755  531  568  490  729   NA  
Operating expenditure6,812  7,366  8,169  9,478  8,266   NA  
Capital expenditure1,536  1,217  1,460  1,810  1,510  1,400F 
Table 2: Key financial indicators (PLN million)
Note: F-forecasted
Source: Polskie Sieci Elektroenergetyczne S.A. (PSE); Global Transmission Report

Over the past few years, the TSO’s operational performance has improved on some fronts while on some parameters, performance has deteriorated. For instance, low ratios such as 1.38 per cent of transmission losses (as compared to 1.77 per cent in 2015) along with 99.77 per cent of availability factor in 2019 testify to a high level of operational reliability of the transmission system and the certainty of supply to consumers connected to PSE’s network.

However, the utility is expected to be watchful with regard to some operational parameters such as energy not supplied (ENS) and average duration of interruptions in the transmission system (AIT). In 2019, ENS increased to 601 MWh from 390 MWh in 2015. Similarly, AIT in 2019 stood at 112 minutes as compared to 87 minutes in 2015.

 2015 2016 2017 2018 2019 2020 
Transmission losses (GWh) 1,833  1,685     1,669  1,611  1,476   NA  
Transmission losses (%) 1.77  1.62       1.601.481.38 NA
Availability factor (at reference value ≥97 per cent) (%)99.4499.7499.7799.9099.77 NA
Energy not supplied or ENS (MWh)390       425672264601 NA
Average duration of interruptions in transmission system (minutes)878411146112 NA
Table 3: Key operational indicators
Source: Polskie Sieci Elektroenergetyczne S.A. (PSE); Global Transmission Report

Future plans

In Poland, power demand is forecast to grow from around 155 TWh in 2019 to 181 TWh in 2030 and 204 TWh in 2040. In view of this, future investment in Poland’s transmission sector is driven by expansion of the national transmission system to provide reliable electricity supply.

Additionally, the National Energy and Climate Plan of Poland (NECP PL) aims to achieve 21 to 23 per cent renewable energy in gross final energy consumption by 2030, and offshore wind will play a significant role in this. Poland forecasts achieving 3.8 GW of offshore wind by 2030 and 8 GW by 2040. Therefore, integration of new generation, especially nuclear units and renewable energy-based plants including offshore wind, will remain a key area of focus for PSE’s future investment plans. Alongside, the TSO will continue to focus on developing and strengthening cross-border interconnections, upgrading and modernising the existing grid and improving the reliability of power supply to consumers.

PSE envisages an investment of over PLN14 billion in its electricity transmission network between 2021 and 2030. The Network Investment Portfolio includes six strategic programmes and three area programmes comprising 164 projects. About PLN9.8 billion will be spent on the portfolio projects comprising network expansion, reconstruction and modernisation. Of this, close to three quarters of the investment will be made on construction of new assets while the remaining is expected to be made on upgrades and modernisation.

Category2021–30 (PLN million)2021–30 (%)
Contracted budget (Network Investment Portfolio)   9,840       70
– Power evacuation and improvement in supply conditions       2,529       19
– Area programmes       4,725       33
– Others       2,586       18
Others (including construction of submarine interconnectors and energy storage facilities)       4,318       30
Total     14,158    100
Table 4: PSE’s planned capital expenditure on transmission network for 2021–30 (PLN million)
Source: Polskie Sieci Elektroenergetyczne S.A. (PSE); Global Transmission Report

PSE’s strategic objective is to build a backbone power network based on 400 kV lines, which will be capable of adapting to the planned development scenario. By 2030, PSE plans to systematically increase the share of 400 kV lines by 3,700 km; reduce the share of 220 kV lines by 378 km; increase transformation capacity by 1,440 MVA at 400/220 kV, by 10,170 MVA at 400/110 kV and by 2,460 MVA at 220/110kV; and increase the reactive power control capacity.

The key future projects include the Harmony Link (Lithuania–Poland link for the synchronisation of Baltic States with the European Union grid); the 400 kV Mikułowa–Czarna line; the 400 kV Ostrołęka–Stanisławów transmission line; the 400 kV Baczyna-Plewiska line; the 400 kV Piła Krzewina–Żydowo line; the 400 kV Kierzkowo–Dunowo line; reconstruction of the 400 kV Gdańsk Błonia–Olsztyn Mątki line; expansion of the 400/110 kV Dobrzeń and 400 kV Stanisławów substations; and construction of a new 400 kV Wyszków substation.

NameVoltageLine length (km)StatusYear of completion
Harmony Link (Poland–Lithuania interconnector)±400 kV HVDC254Under development2025
Mikułowa–Czarna line400 kV AC133Under development2022
Ostrołęka–Stanisławów line400 kV AC106Under development2023
Baczyna-Plewiska transmission project400 kV AC142Under development2024
Piła Krzewina–Żydowo Kierzkowo–Dunowo line400 kV AC163Under development2025
Gdańsk Błonia–Olsztyn Mątki line (reconstruction)400 kV AC135Announced/Planning2029
Table 5: Key planned transmission projects of PSE
Note: HVDC – high voltage direct current; AC – alternating current
Source: Polskie Sieci Elektroenergetyczne S.A. (PSE); Global Transmission Report

In addition, PSE recently announced that it intends to allocate EUR1 billion by 2030 to upgrade its power transmission network in the northern part of the country, so it can transport electricity generated from the planned Baltic offshore wind projects. Poland, which still generates around 70 per cent of its electricity from burning coal, expects to have around 11 GW installed as offshore wind by 2040, which, according to PSE, is equal to 20 per cent of the country’s current power demand.

Other initiatives

Among other key initiatives of PSE is the development of the fundamental market model (FMM), a network model and a remedial action model for the European synchronous area in the region. The aim of the FMM project is to build an electricity market model simulator covering selected European countries. The tool will improve the quality of the Polish Power System (PPS) operation planning and management while meeting security criteria and minimising the costs of energy supply to consumers by implementing planning tools and operational management of the PPS based on the full network model and locational marginal pricing of electricity.

In addition, PSE is also participating in the EU-SysFlex – Pan-European system with an efficient coordinated use of flexibilities for the integration of a large share of renewable energy sources. The project involves 34 organisations from 15 countries across Europe. It aims to provide a road map for Europe in meeting the challenge of integrating at least 50 per cent  renewables by 2030. The project is co-financed by the EU under the Horizon 2020 programme.

Earlier in 2019, PSE joined the OneNet research project, which is also co-financed by EU’s Horizon 2020 programme. Particularly, the TSO is part of the research project titled ‘TSO–DSO–consumer: large-scale demonstrations of innovative grid services through demand response, storage-scale (RES) generation’. The objective of the project is to define, test and demonstrate in the power system environment the functioning of integrated, IT system-based markets and platforms that the TSO and distribution system operators (DSOs) form together for a defined set of ancillary services, where ancillary services can be purchased from system providers, aggregators and end users.

PSE is also undertaking an analysis of the dynamic properties of Power Guardian/SmartValve devices and their interaction with the transmission network. These devices, which can be treated as miniature single-phase shifters, make it possible to regulate the level of load on network assets, including load shedding, which prevents overloads on those assets.


Building the foundations of a resilient, low-emission electricity system in this decade is critical to realising the opportunities for Poland in the coming decades. The utility is determined to build new submarine interconnectors and storage facilities to accommodate renewable energy, especially offshore wind. Meanwhile, it is also expected to focus on reliable power evacuation and improve supply conditions that will provide economic gains and benefit energy consumers.