At the heart of our manufacturing processes are the power plants in Kozienice and Połaniec, as well as thermal power plants located in Bialystok, Piła and Oborniki.

It is here that the main processes of generating electricity and heat are implemented. Production processes taking place within the supply chain are complicated and burdened with many procedures. The coordination of these works enables us to provide Clients with products of the expected quality.

In the production processes we use hard coal, biomass, gas and fuel oils. Coal, which is necessary for production is transported by rail. Our demand for coal is largely fulfilled by LW Bogdanka, and we buy the remaining raw material from external suppliers. We use biomass for thermal energy production in Białystok Heat and Power Plant, and gas for electricity and heat production in Przedsiębiorstwo Energetyki Cieplnej Oborniki (PEC Oborniki) and Miejska Energetyka Cieplna Piła (MEC Piła).

Purchase of raw material
Raw material supply
Quality control
Purchase of raw material


Purchases of the raw material are made on the basis of internal regulations of Enea Wytwarzanie, Enea Elektrownia Połaniec and Enea Trading. Contracts are concluded for: one year, several years or for an indefinite period.


When dealing with raw materials, we require suppliers to confirm the quality of deliveries. We check, among others, the test report, certificates or quality certificates and carry out sieve analysis on the products delivered.


The Purchase of Fuels Office and the Biomass Purchase Office in the Enea Trading Department of Fuel and Logistics supervise the purchasing process.

Raw material supply


Coal to Enea Wytwarzanie in Świerże Górne and Enea Elektrownia Połaniec is delivered by external rail transport based on a monthly delivery schedule. The raw materials are transported within 5 days from the date of payment for the goods. Delivery of a single shipment of coal is on average from 1 to 2 working days and is conditioned by the traffic on railway routes. In the manufacturing processes carried out at Enea, the Połaniec Power Plant biomass is also used. Up to 50% of the raw material is supplied to the Power Plant by road and rail transport. The volume of deliveries in a given month results from transactions concluded by Enea Trading and is based on the agreed daily delivery schedule.

Deliveries of coal to the Bialystok Heat and Power Plant are also carried out via rail transport. Coal is supplied directly from the mine to the Combined Heat and Power Plant based on a separate agreement. After loading coal in the mine, the raw material reaches the Białystok Heat and Power Plant within 2-3 days. In order to complete the order on time, we are obliged to provide the mine with the demand for a given month, by the 25th day of the month preceding the delivery date.  

Białystok Heat and Power Plant uses also biomass and light oil in the manufacturing processes. Up to 71% of biomass supplies are carried out by road transport and 29% by rail. The volume of deliveries for the next week is agreed in the preceding week - until Wednesday for rail deliveries, and by Friday for automotive deliveries. Deliveries of light oil are carried out only by tankers at the expense of the supplier.


The Fuel Purchase Office in Enea Trading is responsible for the delivery of the raw material. The daily biomass supply schedules to the Połaniec Power Plant are updated by the Biomass Clearing Team at Enea Bioenergia.

Quality control


Laboratory tests are performed to check the quality of the raw materials delivered. The quality of hard coal in Enea Wytwarzanie is inspected by its own unit – the Faculty of Chemical Laboratories of Enea Wytwarzanie. On the other hand, tests of the quality of fuels supplied, which include hard coal, mazut and biomass in the Power Plant of Połaniec are carried out by external Laboratories - the Contractor. The process of assessing the quality of raw materials in Enea Wytwarzanie and Enea Elektrownia Połaniec is conducted in a similar way. In the Power Plants during the unloading process, samples of the raw materials are taken from each supply using automatic samplers. In the Enea Wytwarzanie Laboratory and at the Contractor, there is a 4 brigade system, which is why the quality control of deliveries is carried out 24 hours a day. The Employees of the external Laboratory prepare a sample for testing for each delivery. The contractor's Laboratories working in the 1-shift system perform tests in the field of parameters recorded in the current research schedule. During the sampling by an authorized Laboratory worker a visual check is performed. In each of the Power Plants, coal samples from each batch are prepared for elemental analysis of coal. The following coal parameters are analyzed: total moisture content, moisture content in the analytical sample, ash content, sulphur content, heat of combustion and calorific value. The total inspection time of a single sample is about 5 hours with simultaneous determination of the afore-mentioned parameters. In the case of mazut quality control, the following parameters are examined as follows: density at 15 ° C, kinematic viscosity at 100 ° C, ignition temperature, sulphur content, water content, calorific value. When examining forest and non-forest biomass, the following parameters are taken into account: total moisture content, ash content, sulphur content, heat of combustion, calorific value, sieve analysis.

In the event of discrepancies in the analysis, both parties exchange arbitrary samples or organize commission sanctions. The results from the tests performed for a given delivery, the Contractor is obliged to register in the relevant electronic register within no longer than 3 business days from the date of sampling.

Biomass suppliers are obliged to apply practices in accordance with the Integrated Quality, Environmental and Work Safety Management System applicable in manufacturing companies. Additionally, as part of the due diligence system, suppliers are audited by an independent external company. In Enea Elektrownia Połaniec, an audit is conducted for each supplier, which is aimed at checking the ethical and business credibility of the contractor.


The Faculty of Chemical Laboratories Enea Wytwarzanie (DHC) in the area of collection, preparation of fuel samples, performs analyses according to the following standards:

  • Collection and preparation of samples PN-G04502: 2014-11, total moisture PN-80 / G-04511.

The DHC Department applies the following standards and procedures:

  • Production fuel management manual ZA-84-2015-1-I;
  • General procedure PO-15 handling of hard coal samples;
  • Analytical moisture content PN-80 / G-04511 or PN-G-04560: 1998;
  • Ash content PN-80 / G-04512 + Az1: 2002 excl. point. 2.4.2 OR PN-G-04560: 1998;
  • Combustion heat and calorific value PN-81 / G-04513;
  • Total sulphur content PN-G-04584: 2001;
  • Total carbon content PB-01 / TECH.

External Laboratories (Contractor) for fuel quality control for Enea Elektrownia Połaniec use the following standards:

  • Hard coal: PN-G-04502, PN-G-04511, PN-G-04512, PN-G-04584, PN-G-04513 , PN-ISO 1928;
  • Mazut: PN-EN ISO 3170, PN-EN ISO 12185, PN-C-04357, PN-EN ISO 2719, PN-EN ISO 14596, PN-ISO 3733, PN-C-04062;
  • Biomass: PN-EN ISO 18135, PN-EN ISO 18134-2, PN-EN ISO 18122, PN-EN ISO 16994, PN-EN ISO 18125, PN-EN ISO 17827-1.


Production of electricity in both power plants starts with the unloading of coal, which is fed to the boiler bunkers using carburizing strings. This goes to the mills and then to the boiler, to the amount depending on the power of the blocks at a given moment. Steam from the boiler is fed to the turbine, which drives the generator producing electricity. The period after which the coal from carburization will be burned is several hours. The production process is continuous, and its magnitude depends on the power signals given by the National Power Order, depending on the sales plans, reported restrictions and the current situation in the power system.


The quality control of the electricity production process is carried out online by the power system operator, via the LFC system, which acts as an exchange of regulatory data for generating units. On each generating unit (power unit), the amount of electricity produced is monitored with relation to the set value at specific time intervals, most frequently in periods of 15 minutes. In addition, on individual units, the system services that can be provided by individual units are monitored at the request of the power system operator. Any deviations of the power system operator shall be reported to the power plant's services in order to verify and eliminate possible reasons for their occurrence.


The quality control of the production process is defined by the internal Process Monitoring Procedure, through which the process of generating electricity and heat in the Kozienice Power Plant is monitored. Internal procedures and instructions are used in Enea Elektrownia Połaniec, according to which the process of generating electricity and heat is carried out. On the external Client's part, the quality control of the electricity production process is regulated by the Transmission Network Code issued by Polskie Sieci Elektroenergetyczne SA. The quality control of the thermal energy production process is regulated by the provisions of the concluded contracts with heat consumers.