Twin Oaks High School
K-12 School in California, CA · 158 Cassou Rd, San Marcos · 92069
At a glance
Twin Oaks High School is a 28,974-square-foot K-12 school at 158 Cassou Rd, San Marcos in San Marcos, California, built in 1993. In its 2023 California benchmarking disclosure it reported an ENERGY STAR score of 79 out of 100 (grade B), a site energy-use intensity of 17.8 kBtu/ft² and 38 tCO₂e of greenhouse-gas emissions. That score is higher than 47% of the 2,016 scored K-12 school buildings in California.
AB 802 (Public Resources Code §25402.10) · reporting year 2023
Benchmarking record
| Field | Value |
|---|---|
| ENERGY STAR score | 79 (band B) |
| Site EUI | 17.8 kBtu/ft² |
| Source EUI | — |
| GHG emissions | 38 tCO₂e |
| GHG intensity | 1.3 kgCO₂e/ft² |
| Electricity | 155,106 kWh |
| Gross floor area | 28,974 sq ft |
| Source record | california:34394204:2023 |
Compliance context
AB 802 (Public Resources Code §25402.10)
AB 802 requires every California commercial building over 50,000 sq ft to report energy use to the CEC annually; the CEC publicly discloses the results statewide.
Ownership
No owning organisation shown. Names of private individuals in the disclosure are not published here.
Own or manage this building? Claim it to correct the record and get compliance alerts.
Location
- Address
- 158 Cassou Rd, San Marcos
- City
- California
- State
- California
- ZIP
- 92069
- Coordinates
- 33.18028, -117.15888
Within ~1 km
Nearby benchmarked buildings
- Go Green Agriculturescore 100
Office · 164,320 sq ft
- Twin Oaks Elementaryscore 43
K-12 School · 60,046 sq ft
See also: most efficient in California · biggest emitters
How does Twin Oaks High School compare with other K-12 school buildings in California?
The latest disclosures cover 2,128 K-12 school buildings in California, out of 40,029 buildings citywide. Twin Oaks High School's ENERGY STAR score of 79 compares with an average of 74 across the 2,016 that report a score; it scores higher than 47% of them and lower than 52%. Its site EUI of 17.8 kBtu/ft² is about half of the average of 34.6 kBtu/ft² — it uses less energy per square foot than the typical building in that group. Its emissions intensity of 1.3 kgCO₂e/ft² is about 35% below the group average of 2.0 kgCO₂e/ft².
At 28,974 sq ft, it is about 78% below the average floor area of 129,123 sq ft for those buildings. It was built in 1993, 17 years later than the group's average year built (1976). Across all 24 jurisdictions BuildingCensus covers, the 6,548 K-12 school buildings average an ENERGY STAR score of 64 and a site EUI of 52.7 kBtu/ft².
What does an ENERGY STAR score of 79 mean?
ENERGY STAR scores run from 1 to 100 and are computed by the EPA's Portfolio Manager as a percentile against similar buildings nationwide, adjusted for climate, size and use: a score of 79 means the building performs better than about 79% of its national peers. BuildingCensus bands the score into report-card grades; 79 falls in band B — above median (70–84). Scores of 75 or higher meet the threshold for ENERGY STAR certification; certification itself is a separate, verified application that the disclosure does not record. In California, 65% of scored buildings are at 75 or above.
Site energy-use intensity (EUI) is the energy a building uses on site in a year divided by its floor area, in thousand Btu per square foot — lower is more efficient. Twin Oaks High School's 17.8 kBtu/ft² across 28,974 sq ft works out to about 0.5 billion Btu (151 MWh-equivalent) in 2023. The disclosure also reports 155,106 kWh of electricity for the year.
Which law requires Twin Oaks High School to report its energy use?
Twin Oaks High School reports under AB 802 (Public Resources Code §25402.10), the legal basis of California's Building Energy Benchmarking Program (statewide), which publishes each covered building's annual benchmarking results. The record shown here is the report-year 2023 disclosure (source record california:34394204:2023). AB 802 requires every California commercial building over 50,000 sq ft to report energy use to the CEC annually; the CEC publicly discloses the results statewide.
More K-12 school buildings in California
- Alliance Gertz-Ressler Richard Merkin 6-12 Complex· 28,604 sq ft · score 33 (D)
- Lindsay High School· 14,537 sq ft · score 1 (D)
- K-12 School buildings in California· 2,128 benchmarked
- All California benchmarked buildings· AB 802 (Public Resources Code §25402.10)
- Most efficient large buildings in California
- Least efficient large buildings in California
- Biggest emitters in California
Frequently asked questions
What is Twin Oaks High School's energy grade?
Twin Oaks High School scores 79 out of 100 on ENERGY STAR — band B, above median (70–84) — in its 2023 California disclosure. Scores are national percentiles against similar buildings; 75+ qualifies for ENERGY STAR certification.
How much energy does Twin Oaks High School use?
Its 2023 site energy-use intensity was 17.8 kBtu/ft² across 28,974 sq ft, including 155,106 kWh of electricity.
What are Twin Oaks High School's carbon emissions?
Twin Oaks High School reported 38 tCO₂e of greenhouse-gas emissions (1.3 kgCO₂e/ft²) for 2023.
Where is Twin Oaks High School?
Twin Oaks High School is at 158 Cassou Rd, San Marcos, in San Marcos, California 92069. Its coordinates are 33.18028, -117.15888 (latitude, longitude), as published in the Building Energy Benchmarking Program (statewide) file.
How big is Twin Oaks High School and when was it built?
Twin Oaks High School has 28,974 sq ft of gross floor area, as reported in its 2023 disclosure. The disclosure lists 1993 as its year built. It is classed as K-12 school.
Is Twin Oaks High School covered by AB 802 (Public Resources Code §25402.10)?
Yes — it appears in the 2023 Building Energy Benchmarking Program (statewide) disclosure, which lists the buildings reporting under AB 802 (Public Resources Code §25402.10).
Working with California building benchmarking records? Pro adds alerts, change history and CSV export ($49/mo); Enterprise adds full national files, the API and an MCP server for AI tools.
About this data
Source: Building Energy Benchmarking Program (statewide) (AB 802 (Public Resources Code §25402.10)), as published July 9, 2026. See the methodology for how records are matched, cleaned and scored.
Cite as: BuildingCensus, “Twin Oaks High School, San Marcos, California — 2023 benchmarking disclosure”, https://buildingcensus.com/buildings/california/twin-oaks-high-school-4dd90d93 (data as of July 9, 2026).