A change in landuse from agricultural production to energy forest plantations has various environmental impacts. This paper deals with changes in the soil water balance (precipitation excess) and the requirements, uptake and leaching of nitrogen. Results are presented for both agricultural crops and forest plantations in the Netherlands based on simple modelling approaches. Comparisons for calculated and measured leaching data are given for different forest plantations. The change in landuse leads to a reduced recharge of groundwater aquifers and a decrease in nitrogen leaching. Despite lower N leaching, additional fertilizer supply in highly productive energy forest plantations is required with a future reduction in atmospheric N deposition in the Netherlands.