California Utility Allowance Calculator (CUAC)
The California Utility Allowance Calculator (CUAC) is California’s energy consumption model for calculating utility estimates (Treasury Regulation 26 CFR §1.42-10). The CUAC is a tool to provide an estimate of what tenants will pay for utilities and is typically more accurate than a public housing authority (PHA) utility allowance schedule. The CUAC is prepared by qualified energy analysts as defined in CTCAC Regulation Section 10322(h)(21). Use of the CUAC is limited to (upon approval by CTCAC): (i) new construction projects, (ii) rehabilitation projects applying for tax credits in 2018 or later for which the rehabilitation improves energy efficiency by at least 20%, as determined consistent with the requirements of Section 10325(c)(5)(D) and (G), or installs solar generation that offsets 50% of tenant loads, as determined consistent with the requirements of Section 10325(c)(5)(G), and (iii) existing tax credit projects with new photovoltaics installed through the Multifamily Affordable Solar Housing (MASH) program or a solar program administered by a municipal utility or joint powers authority, which offsets tenants’ electrical load. New construction projects must build to the applicable Building Energy Efficiency Standards, Title 24, Part 6 (the Standards) in effect at the time of construction. A unit receiving assistance from the Local PHA in form of a project based voucher (PBV), request and permission must be obtained from the Local PHA UA or HUD, to allow the use of the CUAC on those units. If the owner does not want to apply the CUAC on the PBV units, the owner may use two utility allowance sources per building; the CUAC for the non PBV units and the Local PHA UA for the PBV units. Owners proposing to utilize the CUAC for determining a utility allowance must submit their CUAC package and receive approval from CTCAC according to the CUAC Estimate Submission Requirements (below). If CUAC documentation is not submitted to CTCAC prior to issuance of the Form 8609, a project is no longer eligible to use a CUAC utility allowance.
For existing tax credit projects that qualify under both options (ii) or (iii) noted above {except for projects with active MASH program reservations dated prior to March 1, 2018}, any decrease in a tenant’s utility allowance that results from conversion to the CUAC shall not exceed $15 per month over any 12-month period. CTCAC compliance staff will verify this during the CUAC annual update stage or during upcoming scheduled compliance inspections.
Use of the CUAC requires verification of what is actually built, as opposed to what had been proposed, so that projects are accurately modeled using the most current approved California Energy Commission (CEC) compliance software. Energy analysts using the CUAC shall investigate and confirm the relevant energy efficiency measures actually used in construction of the project once the project has been completed, and model the units and building(s) as built. These relevant energy efficiency measures include any components, materials, systems, etc. that impact the building’s energy efficiency, including but not limited to the building envelope, heating systems, cooling systems, domestic hot water systems, and installed lighting systems. Energy analysts shall also confirm that appliances comply with the applicable California Appliance Efficiency Regulations, Title 20.
Any solar values for new construction or adaptive reuse shall be determined from the CEC’s Photovoltaic Calculator, and any solar values for existing residential buildings shall be determined from the CEC’s Photovoltaic Calculator or the Expected Performance Based Buydown (EPBB) calculator with monthly scalars which are noted below.
Monthly Scalars to be used with Expected Performance Based Buydown (EPBB) calculator to compute solar values for existing residential buildings:
| Month | EPPB Scalar |
|---|---|
| Jan | 0.0468 |
| Feb | 0.0622 |
| Mar | 0.0856 |
| Apr | 0.0972 |
| May | 0.0991 |
| June | 0.1045 |
| July | 0.1080 |
| Aug | 0.1103 |
| Sept | 0.0957 |
| Oct | 0.0799 |
| Nov | 0.0727 |
| Dec | 0.0381 |
Virtual Net Metering
The revised version of the CUAC implements the California Public Utilities Commission Virtual Net Metering (VNM) decision, which can be viewed at the links below:
- https://www.energy.ca.gov/programs-and-topics/programs/building-energy-efficiency-standards/california-utility-allowance
- http://docs.cpuc.ca.gov/PUBLISHED/FINAL_DECISION/139683-03.htm#P103_7069
The new distribution calculation within the CUAC calculator uses a series of weightings reflecting the relationship between affordable Low Income Housing Tax Credit rents, by unit size, throughout California.
The CEC has indicated that while VNM is available to developers with projects in areas served by the Investor Owned Utilities (IOUs) throughout the state, it is not available to projects served by Publicly Owned Utilities (POUs). In addition, the new system implements VNM at the project level, not at the individual building level (the CUAC tracks data at the project-level and apartment-type level, but not at the building-level).
If you have any questions relating to usage of the CUAC calculator please contact Thao Chau, 916-776-7974 of the CEC.
CUAC weighted average worksheet
CUAC Estimate Submission Requirements (Updated May 2018)