Zukünftige Potenziale der nachhaltigen Waldenergieholzversorgung in der Schweiz

A conceptual framework was developed to quantify the effects of ecological and economic constraints on the spatio-temporal availabilities of forest energy wood in Switzerland. Forest energy wood availabilities were simulated over a 40-year period for three forest management scenarios and two timber market situations and with and without subsidies for managing protection forests. Ecological and economic constraints greatly limited forest energy wood availabilities, reducing the theoretical potential equal to the annual wood production of 9–16 million m³/y or 67–118 PJ/y to about one half to one third due to ecological constraints, to one third to one fifth due to additional economic constraints (14–41 PJ/y), and to one tenth or less if subtracting current use. Compared to the current forest management approach, growing stock reduction scenarios increased available amounts of energy wood three to four time over 40 years, particularly in the short term. Favorable energy wood markets increased availabilities by 20%–25%, which subsidies increased by another 30%, particularly in the alpine regions. Under current market prices, the Central Plateau and Jura are promising regions for expanding energy wood mobilization, with greatest untapped potentials and lowest dependence on subsidies. To increase Switzerland’s limited potentials, reducing growing stocks is a reasonable strategy to mobilize more wood fuel from forests during the early energy transition period to make up for possible provisioning gaps of other renewables.