Survey of Emissions Models for Distributed Combined Heat and Power Systems

Will Gans, Anna Monis Shipley, and R. Neal Elliott

January 2007

Abstract

Despite the multitude of benefits, relatively few tools exist for estimating the regional emissions implications of a combined heat and power (CHP) installation (the displaced emissions), or for predicting how CHP will affect constrained transmission systems or distributed emissions implications. Specifically, the impact of a CHP system on regional, utility-generated emissions needs to be quantified and better understood. In general, energy models seek to understand, model, and predict the behavior of energy markets and their effects on the economy.  As proffered in ACEEE’s Statement on Energy Information for the 21st Century, “There is a need for an improved characterization of both technology and behavior in the understanding of the role of energy in a changing world.” That characterization and understanding, in essence, are the purposes of energy models.

The models surveyed in this study vary in design, scope, and detail, but they all seek to capture the functions of an energy economy and use knowledge of economic interactions to simulate the effects of economic and policy changes. In this document, Integrated Planning Model (IPM), Average Displaced Emissions Rate (ADER), Market Allocation (MARKAL), All Modular Industry Growth Assessment (AMIGA), Oak Ridge Competitive Electric Dispatch (ORCED), and National Energy Modeling System (NEMS) models are addressed. The U.S. Environmental Protection Agency’s (EPA) CHP emissions calculator is also investigated. While the approximate operation of each model is discussed, this survey seeks specifically to explain how these models handle emissions and how CHP and thermal energy are considered within the models. Through a better understanding of the existing economic, energy market, and emissions models and their treatment of CHP, it is hoped that a simple, useful tool for the estimation of net avoided utility emissions can be designed.

View full report as a PDF or click to order hard copy.

22 pp., 2007, $16.00, IE071