Planning cogeneration systems

Cogeneration is a proven technique for the simultaneous production of power and heat. Formally, it is defined as the sequential use of a primary energy source to produce two forms of energy, namely heat and power. Cogeneration is widely used in Europe because of its energy efficiency. It was used in this country until the 1950s when its decline was brought on by improved transmission systems, cheap coal and nuclear-generated power. Because the production, transport and sale of electricity is a highly regulated industry, the Carter Administration passed the Public Utilities Regulatory Act (PURA) to foster the development of cogeneration by removing some of the regulatory barriers and providing some benefits to qualified (cogeneration) facilities (QFs). The objective of this article is to discuss an important topic that has been largely overlooked by the engineering community, namely, analysis methods for appropriately sizing cogeneration systems and for estimating annual performance from which reasonably accurate economic projections can be made.