Electrical Submetering in California:
Fact, Fiction and Folly
What is Electrical Submetering?
Many commercial and residential buildings use a single "master meter." Electricity comes into a building at bulk rate prices from the Utility, and landlords bill tenants for electricity based on flat fees or formulas derived from the space they occupy. Occupants pay for electricity as part of a monthly bill, but their energy use is not individually monitored or tracked.
Electrical submetering is the measurement of consumption after the master meter. Submeters (also referred to as power meters, electrical meters, and energy monitors) are installed after the master meter to measure individual electrical load.
The Benefits of Electrical Submetering
One of the most exhaustive examinations of applying electrical submetering to commercial buildings was undertaken by the U.S. Department of Energy as part of the Federal Energy Management Program (FEMP) in 2007. This study showed that merely installing meters resulted in a 2% reduction in energy use through the Hawthorne Effect. 
Put another way, for every five buildings that are submetered, an entirely new building can be powered from the saving.
- Tenants win by saving money and reducing their energy use.
- Landlord’s win with considerably lower energy and operational costs.
- The environment wins with significant reductions in greenhouse gas emissions.
What Laws Govern Electrical Submetering in California?
The purpose of the evaluation is to certify that the design and performance of the meter meet all relevant California laws and regulations. Tests focus on accuracy, operational effectiveness, required markings, and fraud prevention features. Upon successful CTEP evaluation, a Certificate of Approval (COA) is awarded.
Title 24 lays out regulations that govern the construction and redevelopment of residential and non-residential buildings in California. The Standards contain energy and water efficiency requirements for newly constructed buildings, additions to existing buildings, and alterations to existing buildings.
Parts 6 and 11 of Title 24 address the need for regulations to improve energy efficiency and combat climate change. Other portions of Title 24 include building code, electrical code, fire code, and more.
The most significant efficiency improvements to the Standards came in 2019 and included alignment with ASHRAE 90.1 2017. ASHRAE 90.1 has been a benchmark for building energy codes in the United States and a fundamental basis for codes and standards worldwide for more than 35 years. ASHRAE 90.1 is also an industry-standard referenced by the U.S. Green Building Council (USGBC) in the LEED building certification program — and frequently used as a baseline for comparison during energy retrofit projects.
The submetering requirements for new or substantially remodelled non-residential, high-rise residential, and hotel/motel buildings are:
Section 130.5 (a) Service Electrical Metering Requirements: "each electrical service shall have permanently installed user-accessible metering of ‘total energy use’ as per the table below."
Services Rated 50 kVA or Less
Services Rated > 50 kVA and <= 250 kVA
Services Rated > 250 kVA and <= 1000 kVA
Services Rated > 1000 kVA
Instantaneous (at the time) kW Demand
Historical Peak Demand (kW)
kWh Per Rate Period
- Visibility of energy used by tenants
- Disclosure of the cost of electricity to the building owner
- The types of meters that are approved for tenant billing
- Meter sealing requirements
How Much Cost and Effort is Involved?
Multi-point meters have the added advantages of having a much smaller footprint than multiple single-point meters and lower per meter point deployment, integration, and maintenance costs.
Multi-point meters allow for the metering of 6 or more circuits depending on the model and need. They are useful when measuring a large concentrations of circuits and a viable option for multi-load, granular data requirements. Multi-point meters have much smaller footprint than multiple single point meters and lower per meter point deployment, integration, and maintenance costs than single point meters.
- A clear understanding of your building's energy intensiveness, so you know for sure if your facility falls under sections 130.5 (a) and (b) of Title 24 Part 6.
- Complete knowledge of tenant rights as they pertain to electrical submetering and tenant billing.
- What precisely needs to be measured for compliance? How should it be measured? How often? Do you need to keep a historical record of energy use?
- The risks and consequences of non-compliance. Who enforces it? What are the costs of non-compliance? How do you demonstrate compliance?
- Which meters are approved for tenant billing by the CDFA?
- How long can you expect to be able to use a meter?
- What happens when technology and communication protocols evolve? Will your chosen meter keep pace?
- From Space Saver to Information Cornerstone: The Evolution of the Multi-Point Electrical Meter
- Making the Case for Electrical Submeters
- How to Choose the Right Electrical Submeter