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City of Los Angeles - Los Angeles Central Library

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Los Angeles Central Library

Showcase Project: City of Los Angeles

Location

Los Angeles, CA

Project Size

500,000 square feet

Project Cost

$3,700,000

Annual Energy Use (Source EUI)

Baseline
(2012)
180 kBtu/sq. ft.
Expected
(2014)
150 kBtu/sq. ft.
Actual
COMING IN 2014

Expected
Energy Savings:

16%

Annual Energy Cost

Baseline
(2012)
$951,000
Expected
(2014)
$773,000
Actual
COMING IN 2014

Expected
Savings:

$178,000



Background

The historic Los Angeles Central Library Goodhue building was constructed in 1926 and is a Downtown landmark. In 1993, the building was renovated and expanded with the addition of the Tom Bradley Wing. It is the largest library facility in the City and has been a target for energy upgrades since 2006 when it underwent comprehensive lighting retrofits. A 2010 audit identified opportunities to upgrade the building’s HVAC, roofing, and controls system, which is funded through Qualified Energy Conservation Bonds (QECBs).

Solutions

As part of a city-wide energy audit program, 130 buildings—including the Central Library—were identified for cost effective energy efficiency and capital improvement projects. The audits called for the existing pneumatic controls throughout the building to be converted to digital controls. Other recommended energy-efficiency measures (EEMs) included the installation of new high efficiency chillers, variable frequency drives, and a tan reflective roof.

Other Benefits

Since 2009, the City of Los Angeles has launched more than 100 energy efficiency projects, encompassing one million square feet and representing an investment of over $16 million. By creating a more energy-efficient environment, the Central Library will lower its operating costs and improve the control of temperature and humidity throughout the interior spaces, which protects the library’s book collection from mold and improves the overall experience for the over 1.7 million visitors that use the library annually.

New chillers replaced 20 year old units

Solutions

The Central Library expects to reduce its annual electricity consumption by 20%, equal to a savings of 1,372,848 kWh and approximately $178,470 per year at a rate of 13 cents/kWh. The following EEMs are the engines that drive the energy savings for this project:

  • Digital Controls - installation of a direct digital control (DDC) system to reduce HVAC hours and control lighting systems throughout the building. The DDC system is programmed so that zones can go into “unoccupied mode” and temperature/humidity settings can be adjusted for each space type (estimated savings of 460,848 kWh annually).
  • HVAC - The overall cost of the chiller project was $1.1million. Scope of the HVAC upgrades included three new chillers and a cooling tower; variable speed control on the chilled water pump; variable speed controls on air handler fans; sealing leaks in supply air ducts; cleaning the air handler and condenser coils; and repair of outside air dampers and fans. The new chillers replaced the three that were installed as part of 1993 renovation, which still relied on R12 coolant and used more kWh/ton than the replacements (estimated savings of 879,000 kWh annually).
  • Reflective Roof - Replacement of the roof with a tan energy efficient reflective roof. Since the Central Library is one of the shorter buildings in the heart of downtown, library staff was sensitive to their neighbors and opted to install a beige colored roof, instead of a white roof, which have a higher albedo and would have caused more glare for occupants at neighboring hotels and office buildings. The roof was originally covered in black river rock, but because the rocks were not smooth and had sharp edges, they were prone to puncturing the membrane of the roof. The rocks also made it extremely difficult to find leaks. 80,000 lbs of black river rock were removed and a new reflective TPO roof was installed in its place (estimated savings of 33,000 kWh annually).

Cool Roof at the Central Library