The balance principle is the term used in Scandinavia for optimum use of resources in energy supply and use to the lowest cost possible; i.e. much like IRM/LCP in the US. In this report the theoretical basis and possible applications in Sweden of BP are discussed, especially cost and income conepts and the time perspective. Energy markets are described in US, where IRP was initiated, and in Sweden today and in future, after deregulation. Application of BP in Sweden will differ from IRM in US due to different market structure especially in the future when/if the utilities will compete on the market. Technical aspects on IRM/LCP in US are given in an appendix. (44 refs., 6 figs.).