[en] With the intention of maintaining healthy environment in our rivers Vattenfall in 1988 initiated a project called 'Environmentally friendly oils'. The goal was to find oils for bearings and hydraulic systems that would cause less negative environmental effects and still maintain a good technical function. Based on the results of the project it is recommended, for both economical and environmental reasons, to change to synthetic oil in bearings and to hydraulic oil made of white oil in regulating systems. The change may be carried out in connection to other work on the system in question. Special care is recommended when cleaning the system from old oil and dirt. In order to maintain the high quality of the oil, also during manufacturing and assembling, one should follow the recommendations outlined in the report. In bearings where used grease leaks into the river, a grease made of white oil should be used. The quality of the rubber sealings must be adapted to the oil used, in order to secure a good function. In order to bring down the number of products and to create an open market some additional changes is necessary in the specifications of oil. Further research regarding oil and sealing is planned. (3 refs.)