Capabilities

ERI Capabilities

The following ERI Standards are supported:

  • ANSI/RESNET/ICC 301-2014© Standard for the Calculation and Labeling of the Energy Performance of Low-Rise Residential Buildings using an Energy Rating Index

  • ANSI/RESNET/ICC 301-2019 Standard for the Calculation and Labeling of the Energy Performance of Dwelling and Sleeping Units using an Energy Rating Index

The following ENERGY STAR programs/versions are supported:

  • Single Family, National, v3.2, v3.1, v3.0

  • Single Family, Pacific, v3.0

  • Single Family, Florida, v3.1

  • Single Family, Oregon and Washington, v3.2

  • Multifamily, National, v1.2, v1.1, v1.0

  • Multifamily, Oregon and Washington, v1.2

The following IECC ERI versions are supported:

  • 2015

  • 2018

  • 2021

The following DOE ZERH versions are supported:

  • 1.0

  • Single Family, 2.0

  • Multifamily, 2.0

Accuracy vs Speed

The EnergyPlus simulation engine is like a Swiss army knife. There are often multiple models available for the same building technology with varying trade-offs between accuracy and speed. This workflow standardizes the use of EnergyPlus (e.g., the choice of models appropriate for residential buildings) to provide a fast and easy to use solution.

The workflow is continuously being evaluated for ways to reduce runtime without significant impact on accuracy. A number of such enhancements have been made to date.

There are additional ways that software developers using this workflow can reduce runtime:

  • Run on Linux/Mac platform, which is significantly faster by taking advantage of the POSIX fork call.

  • Do not use the --hourly flag unless hourly output is required. If required, limit requests to hourly variables of interest.

  • Run on computing environments with 1) fast CPUs, 2) sufficient memory, and 3) enough processors to allow all simulations to run in parallel.

  • Avoid using the --add-component-loads argument if heating/cooling component loads are not of interest.