The oil crisis in the middle of the seventies meant that the Danish power stations had to change from oil to coal. This meant that the harbours near the power stations had to be expanded and in the mid-eighties, Aarsleff was involved in significant harbour projects in Copenhagen, Fredericia and Aalborg.

Strategy plan to create focus
At the same time, there was a need for fresh initiatives – to concentrate on creating new markets. The first strategy plan in the history of the company focused on electrification of railways, establishment of natural gas and wastewater pipes and trenchless pipe renewal. In all three areas, new or refined techniques were vital to Aarsleff's competitive impact.