Ecosizer

Electrifying water heating is a major decarbonization strategy

The Ecosizer is a free online tool for sizing central heat pump water heating systems (CHPWHs) for multifamily and commercial buildings. The tool is designed to support the adoption of CHPWHs to improve energy efficiency and reduce greenhouse gas emissions. The Ecosizer is also intended to provide educational information on CHPWH system designs to support designers, installers, utility program implementors, building science researchers, manufacturers, and policy makers.

The sizing method used by the Ecosizer was developed in 2020 by Ecotope, Inc. This method provides a significant improvement to the ASHRAE sizing method for water heating systems, allowing the system to be sized more accurately and smaller than the ASHRAE method.

Water heating system sizing includes heating capacity and hot water storage volume needed to meet peak hot water demand on the design day. This method provides the minimum heating capacity and storage volume needed to meet this anticipated peak hot water demand.

The Ecosizer tool provides a primary sizing curve to determine required HPWH heating capacity and storage volume according to equipment characteristics. Users need to select HPWHs according to their heating capacity under the design day weather conditions (usually the coldest day).
The Ecosizer can use a custom hot water load shape to allow sizing for any specific hot water demand or can use preset multifamily or ASHRAE commercial building load shapes. It can also provide a means to size systems to allow for different periods of load shifting to time operation of the system with demands of the grid.