William Tell
Multifamily Housing in Denver, CO · 1599 Williams St. · 80218
At a glance
William Tell is a 57,993-square-foot multifamily housing building at 1599 Williams St. in Denver, Colorado, built in 1964. In its 2023 Denver benchmarking disclosure it reported an ENERGY STAR score of 44 out of 100 (grade D), a site energy-use intensity of 92.2 kBtu/ft² and 436 tCO₂e of greenhouse-gas emissions. That score is higher than 10% of the 956 scored multifamily housing buildings in Denver.
Energize Denver Building Performance Policy · reporting year 2023
Benchmarking record
| Field | Value |
|---|---|
| ENERGY STAR score | 44 (band D) |
| Site EUI | 92.2 kBtu/ft² |
| Source EUI | — |
| GHG emissions | 436 tCO₂e |
| GHG intensity | — |
| Electricity | 436,130 kWh |
| Natural gas | 38,575 therms |
| Gross floor area | 57,993 sq ft |
| Source record | denver:2783:2023 |
The disclosure history
Year over year
| Year | Score | Δ | Site EUI | GHG emissions |
|---|---|---|---|---|
| 2023latest | 44 | -12 | 92.2 kBtu/ft² | 436 tCO₂e |
| 2022 | 56 | +14 | 87.7 kBtu/ft² | 415 tCO₂e |
| 2021 | 42 | 97.9 kBtu/ft² | 460 tCO₂e |
Compliance context
Energize Denver Building Performance Policy
Energize Denver sets energy-use (EUI) targets for buildings of 25,000+ sq ft — for most buildings an interim target in 2028 and a final target in 2032 — with civil penalties of roughly $0.15–0.35 per kBtu over target for non-compliance.
Ownership
No owning organisation shown. Names of private individuals in the disclosure are not published here.
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Location
- Address
- 1599 Williams St.
- City
- Denver
- State
- Colorado
- ZIP
- 80218
Within ~1 km
Nearby benchmarked buildings
This source publishes no coordinates, so nearby buildings can't be resolved yet.
See also: most efficient in Denver · biggest emitters
How does William Tell compare with other multifamily housing buildings in Denver?
The latest disclosures cover 1,108 multifamily housing buildings in Denver, out of 3,287 buildings citywide. William Tell's ENERGY STAR score of 44 compares with an average of 78 across the 956 that report a score; it scores higher than 10% of them and lower than 89%. Its site EUI of 92.2 kBtu/ft² is about 62% above the average of 57.0 kBtu/ft² — it uses more energy per square foot than the typical building in that group.
At 57,993 sq ft, it is about half of the average floor area of 126,139 sq ft for those buildings. It was built in 1964, 26 years earlier than the group's average year built (1990). Across all 24 jurisdictions BuildingCensus covers, the 59,945 multifamily housing buildings average an ENERGY STAR score of 70 and a site EUI of 59.0 kBtu/ft².
How has William Tell's energy performance changed over time?
BuildingCensus holds 3 Denver disclosures for William Tell, covering report years 2021–2023. Its ENERGY STAR score went from 42 in 2021 to 44 in 2023 (+2 points); its best year on file was 2022, at 56. Site EUI moved from 97.9 kBtu/ft² (2021) to 92.2 kBtu/ft² (2023), a 6% decrease. Reported emissions went from 460 tCO₂e to 436 tCO₂e over the same span (down 5%).
What does an ENERGY STAR score of 44 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 44 means the building performs better than about 44% of its national peers. BuildingCensus bands the score into report-card grades; 44 falls in band D — lowest band (1–54). It sits 31 points below 75, the threshold for ENERGY STAR certification. In Denver, 54% 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. William Tell's 92.2 kBtu/ft² across 57,993 sq ft works out to about 5.3 billion Btu (1,567 MWh-equivalent) in 2023. The disclosure also reports 436,130 kWh of electricity and 38,575 therms of natural gas for the year.
Which law requires William Tell to report its energy use?
William Tell reports under the Energize Denver Building Performance Policy, the legal basis of Denver's Energize Denver Benchmarking program, which publishes each covered building's annual benchmarking results. The record shown here is the report-year 2023 disclosure (source record denver:2783:2023). Energize Denver sets energy-use (EUI) targets for buildings of 25,000+ sq ft — for most buildings an interim target in 2028 and a final target in 2032 — with civil penalties of roughly $0.15–0.35 per kBtu over target for non-compliance.
More multifamily housing buildings in Denver
- Humboldt Place Homeowners Association Llc· 57,728 sq ft · score 98 (A)
- Parkside Apartments· 57,654 sq ft · score 74 (B)
- University Lofts· 57,512 sq ft · EUI 83.0 kBtu/ft²
- Eliot Street Apartments· 57,111 sq ft · score 99 (A)
- Sable Ridge Residences· 57,063 sq ft · score 78 (B)
- Monaco Parkway Apartments· 57,006 sq ft · score 60 (C)
- Multifamily Housing buildings in Denver· 1,108 benchmarked
- All Denver benchmarked buildings· Energize Denver Building Performance Policy
- Most efficient large buildings in Denver
- Least efficient large buildings in Denver
- Biggest emitters in Denver
Frequently asked questions
What is William Tell's energy grade?
William Tell scores 44 out of 100 on ENERGY STAR — band D, lowest band (1–54) — in its 2023 Denver disclosure. Scores are national percentiles against similar buildings; 75+ qualifies for ENERGY STAR certification.
How much energy does William Tell use?
Its 2023 site energy-use intensity was 92.2 kBtu/ft² across 57,993 sq ft, including 436,130 kWh of electricity and 38,575 therms of natural gas.
What are William Tell's carbon emissions?
William Tell reported 436 tCO₂e of greenhouse-gas emissions for 2023.
Where is William Tell?
William Tell is at 1599 Williams St., in Denver, Colorado 80218.
How big is William Tell and when was it built?
William Tell has 57,993 sq ft of gross floor area, as reported in its 2023 disclosure. The disclosure lists 1964 as its year built. It is classed as multifamily housing.
Is William Tell covered by the Energize Denver Building Performance Policy?
Yes — it appears in the 2023 Energize Denver Benchmarking disclosure, which lists the buildings reporting under the Energize Denver Building Performance Policy.
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About this data
Source: Energize Denver Benchmarking (Energize Denver Building Performance Policy), as published July 9, 2026. See the methodology for how records are matched, cleaned and scored.
Cite as: BuildingCensus, “William Tell, Denver, Colorado — 2023 benchmarking disclosure”, https://buildingcensus.com/buildings/denver/william-tell-01085b33 (data as of July 9, 2026).