Below is a summarized version of the webinar video above. This article will cover:
Existing Single Family Study Update
What’s new?
• Updated costs through a contractor survey
• Utility tariff escalation sensitivity analysis
• Updated Net Billing Tariff (NBT) Rate
• Updated software (2025 CBECC-Res research version)
• Updated Utility Rates
• New Measures: Ductless HVAC, HPWH Tank Locations
Methodology
Assumptions:
Individual space conditioning and water heating systems, one per single family building.
Split-system air conditioner with natural gas furnace.
Small storage natural gas water heater.
Gas cooktop, oven, and clothes dryer.
Three Vintages: Pre-1978, 1978-1991, 1992-2010
2 Cost-Effectiveness Methodologies:
1. “On-Bill” customer focus
IOU TOU rates based on region
Rate escalation over time
2. Long-term System Cost (LSC):
Long-term cost of operating California’s energy system
How to Find these Results in the Explorer
You can find these results at explorer.localenergycodes.com, by clicking on Results in the sidebar. Make sure that the Existing Buildings tab is selected at the top of the page.
There are benefit to cost ratios for both On-Bill and LSC, as mentioned above, and results for On-Bill Cost-Effectiveness are available for both 2022 and 2025 escalation rates. There are small, orange warnings next to Annual Bill Savings and Lifecycle Savings because these values displayed are based solely on the 2025 escalation rates. The spreadsheet with the full list of results for both escalation rates is in that warning and can also be downloaded here. That spreadsheet also contains the full list of measures included in the analysis, of which the Explorer is displaying a limited set.
Summary of Study Results
• Envelope: Improving envelope performance is very cost-effective in many older homes.
• Duct measures: Many older homes have leaky duct systems that should be replaced at end of life (20-30 yrs).
• HPSH: LSC cost-effective in most climate zones.
• HPWH: LSC cost-effective in all climate zones.
• PV: Less utility cost savings under NBT, favors on site utilization of PV generation.
• Next steps: AC to HP replacement, to be discussed further.
Creating a Flexible Policy in the Explorer with these Study Results
To follow along with creating a policy in the Explorer, watch the video at the top of this page from 52:00 on.