71428A (UNION SQUARE MAIN)
Commercial in San Francisco, CA · 170 O'FARRELL ST · 94102
At a glance
71428A (UNION SQUARE MAIN) is a 922,758-square-foot commercial building at 170 O'FARRELL ST in San Francisco, California, built in 1946. In its 2025 San Francisco benchmarking disclosure it reported an ENERGY STAR score of 47 out of 100 (grade D), a site energy-use intensity of 47.2 kBtu/ft² and 2,434 tCO₂e of greenhouse-gas emissions. That score is higher than 11% of the 790 scored commercial buildings in San Francisco.
SF Environment Code Chapter 20 · reporting year 2025
Benchmarking record
| Field | Value |
|---|---|
| ENERGY STAR score | 47 (band D) |
| Site EUI | 47.2 kBtu/ft² |
| Source EUI | 106.8 kBtu/ft² |
| GHG emissions | 2,434 tCO₂e |
| GHG intensity | 2.6 kgCO₂e/ft² |
| Electricity | 8,848,240 kWh |
| Natural gas | 133,276 therms |
| Gross floor area | 922,758 sq ft |
| Source record | sf:0314/018:2025 |
The disclosure history
Year over year
| Year | Score | Δ | Site EUI | GHG emissions |
|---|---|---|---|---|
| 2025latest | 47 | -17 | 47.2 kBtu/ft² | 2,434 tCO₂e |
| 2024 | 64 | -5 | 43.4 kBtu/ft² | 2,547 tCO₂e |
| 2023 | 69 | +1 | 42.7 kBtu/ft² | 2,616 tCO₂e |
| 2022 | 68 | +2 | 42.5 kBtu/ft² | 2,550 tCO₂e |
| 2021 | 66 | 41.7 kBtu/ft² | 2,240 tCO₂e | |
| 2020 | — | 35.3 kBtu/ft² | 2,060 tCO₂e | |
| 2019 | — | — | — | |
| 2018 | 36 | -35 | 62.7 kBtu/ft² | 3,803 tCO₂e |
| 2017 | 71 | +4 | 62.8 kBtu/ft² | 4,059 tCO₂e |
| 2016 | 67 | +1 | 65.3 kBtu/ft² | 4,724 tCO₂e |
| 2015 | 66 | +3 | 67.5 kBtu/ft² | 4,638 tCO₂e |
| 2014 | 63 | -4 | 70.5 kBtu/ft² | 4,811 tCO₂e |
| 2013 | 67 | ±0 | 69.0 kBtu/ft² | 4,977 tCO₂e |
| 2012 | 67 | -2 | 72.1 kBtu/ft² | 5,287 tCO₂e |
| 2011 | 69 | 68.0 kBtu/ft² | 5,073 tCO₂e |
Compliance context
SF Environment Code Chapter 20
San Francisco's ordinance requires annual benchmarking for commercial buildings over 10,000 sq ft, with administrative penalties for buildings that fail to report.
Ownership
No owning organisation shown. Names of private individuals in the disclosure are not published here.
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Location
- Address
- 170 O'FARRELL ST
- City
- San Francisco
- State
- California
- ZIP
- 94102
- Coordinates
- 37.78700, -122.40717
Within ~1 km
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- 555 California Streetscore 76
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See also: most efficient in San Francisco · biggest emitters
How does 71428A (UNION SQUARE MAIN) compare with other commercial buildings in San Francisco?
The latest disclosures cover 1,683 commercial buildings in San Francisco, out of 2,509 buildings citywide. 71428A (UNION SQUARE MAIN)'s ENERGY STAR score of 47 compares with an average of 78 across the 790 that report a score; it scores higher than 11% of them and lower than 89%. Its site EUI of 47.2 kBtu/ft² is roughly in line with the average of 49.2 kBtu/ft² — it uses less energy per square foot than the typical building in that group. Its emissions intensity of 2.6 kgCO₂e/ft² is roughly in line with the group average of 2.7 kgCO₂e/ft².
At 922,758 sq ft, it is about 759% above the average floor area of 107,408 sq ft for those buildings. It was built in 1946, 5 years later than the group's average year built (1941). Across all 24 jurisdictions BuildingCensus covers, the 2,307 commercial buildings average an ENERGY STAR score of 76 and a site EUI of 51.3 kBtu/ft².
How has 71428A (UNION SQUARE MAIN)'s energy performance changed over time?
BuildingCensus holds 15 San Francisco disclosures for 71428A (UNION SQUARE MAIN), covering report years 2011–2025. Its ENERGY STAR score went from 69 in 2011 to 47 in 2025 (-22 points); its best year on file was 2017, at 71. Site EUI moved from 68.0 kBtu/ft² (2011) to 47.2 kBtu/ft² (2025), a 31% decrease. Reported emissions went from 5,073 tCO₂e to 2,434 tCO₂e over the same span (down 52%).
What does an ENERGY STAR score of 47 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 47 means the building performs better than about 47% of its national peers. BuildingCensus bands the score into report-card grades; 47 falls in band D — lowest band (1–54). It sits 28 points below 75, the threshold for ENERGY STAR certification. In San Francisco, 73% 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. 71428A (UNION SQUARE MAIN)'s 47.2 kBtu/ft² across 922,758 sq ft works out to about 43.6 billion Btu (12,764 MWh-equivalent) in 2025. Its source EUI of 106.8 kBtu/ft² also counts the energy lost generating and delivering that power, which is why it is higher. The disclosure also reports 8,848,240 kWh of electricity and 133,276 therms of natural gas for the year.
Which law requires 71428A (UNION SQUARE MAIN) to report its energy use?
71428A (UNION SQUARE MAIN) reports under SF Environment Code Chapter 20, the legal basis of San Francisco's Existing Buildings Energy Performance Ordinance, which publishes each covered building's annual benchmarking results. The record shown here is the report-year 2025 disclosure (source record sf:0314/018:2025). San Francisco's ordinance requires annual benchmarking for commercial buildings over 10,000 sq ft, with administrative penalties for buildings that fail to report.
More commercial buildings in San Francisco
- Park Tower 250 Howard· 908,361 sq ft · score 72 (B)
- Hyatt Regency San Francisco· 882,977 sq ft · score 93 (A)
- 1355 Market St· 829,730 sq ft · EUI 25.2 kBtu/ft²
- 345 CALIFORNIA ST· 814,226 sq ft · score 88 (A)
- Fairmont Hotel - San Francisco· 804,136 sq ft · score 83 (B)
- 50 California Street· 785,149 sq ft · score 97 (A)
- Commercial buildings in San Francisco· 1,683 benchmarked
- All San Francisco benchmarked buildings· SF Environment Code Chapter 20
- Most efficient large buildings in San Francisco
- Least efficient large buildings in San Francisco
- Biggest emitters in San Francisco
Frequently asked questions
What is 71428A (UNION SQUARE MAIN)'s energy grade?
71428A (UNION SQUARE MAIN) scores 47 out of 100 on ENERGY STAR — band D, lowest band (1–54) — in its 2025 San Francisco disclosure. Scores are national percentiles against similar buildings; 75+ qualifies for ENERGY STAR certification.
How much energy does 71428A (UNION SQUARE MAIN) use?
Its 2025 site energy-use intensity was 47.2 kBtu/ft² (106.8 kBtu/ft² source) across 922,758 sq ft, including 8,848,240 kWh of electricity and 133,276 therms of natural gas.
What are 71428A (UNION SQUARE MAIN)'s carbon emissions?
71428A (UNION SQUARE MAIN) reported 2,434 tCO₂e of greenhouse-gas emissions (2.6 kgCO₂e/ft²) for 2025.
Where is 71428A (UNION SQUARE MAIN)?
71428A (UNION SQUARE MAIN) is at 170 O'FARRELL ST, in San Francisco, California 94102. Its coordinates are 37.78700, -122.40717 (latitude, longitude), as published in the Existing Buildings Energy Performance Ordinance file.
How big is 71428A (UNION SQUARE MAIN) and when was it built?
71428A (UNION SQUARE MAIN) has 922,758 sq ft of gross floor area, as reported in its 2025 disclosure. The disclosure lists 1946 as its year built. It is classed as commercial.
Is 71428A (UNION SQUARE MAIN) covered by SF Environment Code Chapter 20?
Yes — it appears in the 2025 Existing Buildings Energy Performance Ordinance disclosure, which lists the buildings reporting under SF Environment Code Chapter 20.
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About this data
Source: Existing Buildings Energy Performance Ordinance (SF Environment Code Chapter 20), as published October 2, 2026. See the methodology for how records are matched, cleaned and scored.
Cite as: BuildingCensus, “71428A (UNION SQUARE MAIN), San Francisco, California — 2025 benchmarking disclosure”, https://buildingcensus.com/buildings/san-francisco/71428a-union-square-main-c14725dd (data as of October 2, 2026).