DER CONCEPTS

Introduction to DER

Massachusetts gas and electric utilities are sponsoring a limited Deep Energy Retrofit (DER) program to provide support to customers who wish to incorporate a deep energy retrofit as part of regular maintenance or remodeling activities. This guide is intended to provide the technical framework for this program.

The guide is composed of two parts. Part 1 explains fundamental DER concepts and outlines prerequisite measures for DER projects participating in the DER program. Part 2 provides specific technical guidance for the high performance retrofit of residential building enclosures. This technical guidance is presented in the form of illustrated schematic details accompanied by explanatory text and notes.