Energy derived from fossil fuels will unavoidably become more expensive. Future developments in the price of wood are manageable by comparison.
The price of fossil fuels has jumped in unpredictable leaps, yet constantly increased (something that was considered unlikely ten years ago). This situation will probably not improve in the medium term. The demand, particularly for crude oil, will continue to increase due to the growth of countries such as China and India, and the price inexorably along with it.