1314 6. METHANE EMISSIONS FROM COAL MINES The downward trend in hard coal mining in Poland has persisted for almost 30 years and has been particularly pronounced in recent years, driven by significantly lower demand for coal energy and increased competition in world markets. In 2024, hard coal mining in Poland amounted to 43.7 million tonnes, 3.8 million tonnes (i.e., 8%) lower than in 2023, when it amounted to 47.5 million tonnes. Over the last 10 years, hard coal production has fallen by 54.4 million tonnes (i.e. by 55.4%) and over the last 20 years it has fallen by 91.5 million tonnes (i.e. by 67.7%). In the Polish mining industry, as production decreases, the depth of exploitation increases, which is associated with higher methane emissions per ton of extracted coal. In 2024, the highest methane emission intensity per tonne of coal recorded so far was 16.5 m3 CH4/t, an increase of 0.7 m3 CH4/t (i.e., 4.4%) compared with 2023. Over the last 10 years, methane emission intensity has almost doubled, and over the last 20 years, it has tripled (Fig. No. 4). Figure 4 - Methane emission intensity in Poland in 1993 ÷ 2024 The release of methane into mine workings creates a methane hazard. It is a fundamental source of danger to the safety of the mining crew and the continuity of mine traffic because the mixture of air and methane, depending on its concentration, can be flammable or highly explosive, and at high concentrations it displaces oxygen, creating an atmosphere unsuitable for respiration. Absolute methane content is often used as a measure of the methane hazard status of a mine, i.e., the sum of the methane released into the excavation and the methane in the used air discharged by the current (ventilation methane content, VAM) and captured by the methane removal system. However, the amount of methane flowing into mine workings is determined by the current location of the mining workings. Changing patterns of exploitation fronts mean that the methane content in mines can vary widely throughout the year. To ensure safety and prevent explosive atmospheres, ventilation (dilution of methane with air and its discharge to the surface by air currents), rock mass methane drainage (drainage wells and discharge of methane through pipelines to methane drainage stations), or a combination of both is used. In the Polish hard coal mining industry, the downward trend in absolute methane content has been maintained for years. In 2024, it amounted to 722.1 million m3/year and was the lowest value recorded to date. Compared to 2023, it has decreased by 30.0 million m3/year (i.e., 4.0%), and compared to 2017, it has decreased by 266.4 million m3/year (i.e., 23.9%). The mines with the highest absolute methane content are: KWK „Knurów-Szczygłowice” (145.8 million m3/year), KWK „Borynia-Zofiówka” (87.6 million m3/year) and KWK „Pniówek” (79.6 million m3/year). Similar trends are observed in the development of the amount of ventilation methane. In 2024, it amounted to 446.3 million m3/year (the lowest value so far) and decreased compared to 2023 by 22.6 million m3/year (i.e. by 4.08%), and compared to 2017, it decreased by 165.2 million m3/year (i.e., by 27.0%). The size of methane drainage in 2024 amounted to 275.8 million m3/year and was
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