International comparisons show that the refinery at Slagentangen is on the list of refineries having the world's most efficient energy use. Since the start of the 1990's, the refinery has implemented internal measures to save energy, and the use of energy today is 25% more effective than in 1990. The fact that emissions of CO2 still has increased over this period, is mainly due to new environmental demands to products, i.a. increased desulfurization. Furthermore, the refinery has increased its crude oil treatment capacity.