Fuelwood S4 as a Forest Bioenergy Resource in Poland: Price and Sales Volume Dynamics

This study aims to examine fuelwood S4 as a forest bioenergy resource in Poland by analysing real price dynamics, sales-volume changes and short-term price–volume relationships in 2005–2024. This study contributes to the literature by linking the S4 fuelwood assortment with local biomass-energy availability and by analysing its monthly price–volume dynamics in an institutionally managed primary timber market. Monthly data from the State Forests National Forest Holding for five species groups—pine, spruce, oak, beech and birch—were used. The analysis combined descriptive statistics, seasonal indices, stationarity and cointegration diagnostics, Granger-type predictive tests and autoregressive distributed lag (ARDL)-type fixed-effects dynamic panel models. The results show that sales volume was more volatile than real prices and displayed strong seasonality, with the highest average sales in March and the lowest in January. Pine accounted for the largest share of sales volume, while oak and beech represented higher-priced segments. Between 2005 and 2024, total timber sales increased by 27.1%, whereas S4 fuelwood sales increased by 77.0%. The diagnostics did not provide consistent evidence of a stable long-term equilibrium between real prices and sales volume; therefore, the main econometric analysis focused on short-term dynamics. Lagged real price changes were positively and significantly associated with subsequent sales-volume dynamics, and this relationship remained robust across alternative lag specifications. The sum of lagged real-price coefficients was positive and statistically significant in all ARDL-type specifications, ranging from 1.053 to 2.162, with Wald-test p-values from <0.001 to 0.018. The findings indicate that fuelwood S4 should be interpreted not only as a timber assortment, but also as a limited forest bioenergy resource whose market behaviour is shaped by species structure, seasonal patterns and short-term adjustment within an institutionally managed timber sales system.