REA: resource exergy analysis - Calculation guide for energy systems, including district heating and cooling

The REA calculation guide is the documentation and extension of the resource exergy analysis (REA), which has already been successfully applied in various research and practical projects since 2010.

The REA makes it possible to determine resource consumption in energy systems in a simple and physically sound manner. This helps to minimize resource waste and indirect greenhouse gas emissions.

If REA is combined with greenhouse gas emission analyses, climate-friendly combinations of supply systems and consumers can be reliably identified. In particular, district heating and district cooling, which can often only be assessed with insufficient accuracy due to their complexity, often show their best side when assessed with the REA.

The calculation guide contains an introduction to REA, as well as explanations of various methodological aspects and concrete calculation instructions for the analysis of electricity, heating and cooling supply systems in the context of the connected consumers.

In addition, a collection of life cycle analysis data is provided in the calculation guide, which enables an easy application of the presented calculation rules. Complementary to resource energy factors, greenhouse gas emission factors for an observation period of 100 years (assessment of long-term effects) and 20 years (avoidance of tipping points) are listed from the same source database. This should enable the REA to be used as a supplement to well-founded greenhouse gas emissions analysis using a consistent database.

The calculation guide is concluded by comprehensive examples illustrating how different district heating and cooling energy systems can be evaluated and compared using the REA.

The REA calculation guide in English and the REA Berechnungsleitfaden in German are available for download.

The life cycle data, which can be used for the REA and a complementary greenhouse gas emissions analysis, are also available in the English original as an Excel spreadsheet.

A presentation on the genesis of the REA in German provides a brief overview of some application examples of the analysis methodology.

Questions about the REA calculation guide can be sent by e-mail to