This paper studies linear cost-efficiency and quality incentives that are increasingly being used to regulate electricity and gas network utilities. The analysis shows that cost and quality incentives have asymmetric impacts on firms’ choices of efficiency and quality, and that the incentive powers should be equal and less than maximal when there is information asymmetry about firm costs and a dislike for network utility surplus. As in most existing regulations quality incentives have a higher power than cost-efficiency incentives, the model predicts that supplied quality is too high. Finally, the paper discusses examples of linear sliding-scale incentive regulation in Norway and Great Britain. The findings of this study provide guidance for regulators and policymakers looking to optimally use linear incentives to regulate energy network utilities.