Available utilities and fuel sources

Early in the project, the design team must evaluate the site's available utilities and fuel sources. They can then decide whether to design a building that uses multiple fuel sources (e.g., electricity and natural gas) or an all-electric building. Additionally, some locations may have multiple utility provider or rate options. There are numerous websites available to help determine what utilities are available at your project's site. See below in the resources section for some examples.

Utility selection considerations

Many projects will be designed using mixed-fuel systems. This means that some loads (e.g., lighting, plug loads, air-conditioning) are served by electricity while others (e.g., heating, hot water, cooking) are served by natural gas or other fossil fuels.

Some project sites may not have natural gas available. In this case, all-electric systems must be selected for heating, hot water, and cooking. Alternately, other fossil fuels such as propane may be used if appropriate.

Some project sites may have natural gas available, but may opt to design an all-electric building to reduce the carbon impacts associated with the building's energy use. California has adopted many local ordinances that either encourage or mandate all-electric buildings in new construction.

Some sites may have multiple electricity providers serving the site. This may include a "traditional" electricity provider and an alternative provider that offers electricity from renewable sources. In some cases, the electric utility may offer both a standard rate and a rate for clean(er) electricity. Refer to the additional resources section below for links to some websites that can help identify utility providers based on input location.

Understanding emissions associated with electricity generation at a project site

Comparison of emissions associated with electricity generation between New England (red) and the national average (blue) using the EPA Power Profiler tool

If an all-electric design is being pursued, then it is important to understand the carbon and other emissions of the electricity generation in the project's region. In the United States, electricity is generated in many different ways, with a wide variation in environmental impact. Electricity generation from the combustion of fossil fuels contributes toward unhealthy air quality, acid rain, and global climate change. The United States Environmental Protection Agency (EPA) has created a tool called the Power Profiler which compares the emissions associated with electricity generation in a selected region compared to the national average, or other regions in the country.

To compare the fuel mix (i.e., resource mix) and air emission rates of the electricity in your region to the national average and to determine the air emissions that result from electricity use in your home or business, either select the appropriate eGRID subregion or enter your ZIP code to determine the appropriate eGRID subregion.

Power Profiler does not provide information about the environmental attributes of electric power generated by individual companies. For company-specific information, access EPA's eGRID database.

Role of BEM practitioner

The decision of which fuels to use for a project will likely be made between the architect, engineer, and owner. However, if the team is unsure about whether to design a mixed-fuel or all-electric, energy models can help provide valuable information.

Modeling approach

• Get or build model - An early stage analysis may use a prototype model of the proposed building type. If the building massing has been developed, a new model could be created to more closely match the conceptual geometry, although this would necessitate defining other inputs (likely similar to those in a prototype model).
• Make two versions of the model - If two versions of the prototype already exist (mixed-fuel and all-electric), then this will make your life easier but this is not the case for most prototypes. Likely, you will need to create a copy of the prototype and change the heating, hot water, and cooking fuel sources to electricity.
• Set models up to generate desired metrics - these may include:
  • Site energy
  • Source energy
  • Utility costs (often done with simple rate estimates during the early stages)
  • Greenhouse gas emissions
• Produce comparative results (e.g. in a table) that conveys the energy, cost, and emissions impacts of the mixed fuel vs. electric design options.
• Gather detailed utility rate schedule information. This will be useful in later stages for performing economic analysis of different design options, selecting a rate structure from the utility company (if multiple options exist), analyzing cost savings associated with load-shifting.

Additional resources

• https://findenergy.com/ - a website that allows users to look up and compare available electric and natural gas utility rates for a specified location.
• https://www.inmyarea.com/utilities - available utilities lookup by zip code.

Links to external websites are provided as a convenience for further research, but do not imply any endorsement of the content or the operator of the external site, as detailed in BEMcyclopedia's general disclaimers.