Energy Return on Investment (EROI) for Distributed Power Generation from Low-Temperature Heat Sources Using the Organic Rankine Cycle

Abstract

Energy Return on (Energy) Investment, EROI, is a measure of the future energy benefit from energy expenditure. EROI can be used in addition to price signals to determine how an energy technology should inform energy policy. Organic Rankine Cycle (ORC) technologies are employed in a wide variety of plant sizes, designs and locations. The relationship between the capital cost of an energy generation technology and its EROI is non-linear, which suggests ORC technology has a wide range of possible EROI values depending on its design and size. This paper investigates the EROI of two ORC electricity generation plants and evaluates this against other technologies. The first part of the paper investigates two ORC power plants as case studies. This investigation is to produce an estimate of the energy input required to build the plants and the resulting EROI. The second part of the paper briefly evaluates the calculated EROI compared to other technologies, and how this comparative energy cost might inform energy policy.