Project Summary and Analysis

Abstract

The book “DER Energy Retrofit—Case Studies” contains 26 well-documented case studies from Europe (Austria, Denmark, Estonia, Germany, Ireland, Latvia, Montenegro, The Netherlands, United Kingdom) and the United States. After data were collected, the case studies were analyzed with respect to energy use (before and after renovation), reasons for undertaking the renovation, co-benefits achieved, project cost-effectiveness, and the business models used in project implementation. Finally, “lessons learned” were compiled and compared. Based on an extensive literature review and lessons learned from these case studies, the IEA-EBC Annex 61 team has proposed the following definition of the DER:

Deep Energy Retrofit (DER) is a major building renovation project in which site energy use intensity (including plug loads) has been reduced by at least 50% from the pre-renovation baseline with a corresponding improvement in indoor environmental quality and comfort.

Lessons learned from the case studies and experiences of the project team clearly indicate that DER can be achieved with the application of “bundles” of a limited number of core technologies readily available on the market. Specific characteristics of some of these core technology bundles generally depend on the technologies available in an individual nation’s market, on the minimum requirements of national standards, and on economics (as determined by a life cycle cost [LCC] analysis). Also, requirements for building envelope-related technologies (e.g., insulation levels, windows, vapor and water barriers, and requirements for building airtightness) will depend on specific climate conditions. Case studies documented in this book were combined with original research conducted under Annex 61 and information collected from literature research and expert discussions conducted at Annex 61 Industry Forums to develop several guidelines that were published by Springer: “Deep Energy Retrofit—A Guide to Achieving Significant Energy Use Reduction with Major Renovation Projects”, Deep Energy Retrofit Guide for Public Buildings—Business and Financial Models”, which describes business models for DER, project structuring and project financing options, direct cost savings benefits and monetizing of indirect benefits, and macro- and microeconomic barriers for implementation of DER projects in the public building sector and “Deep Energy Retrofit—a Guide for Decision Makers”.