UC Los Angeles Campus & Medical Center Strategic Energy Plan ...

water use to be provided, a solar hot water system was sized to meet demand. The cost of an
appropriate system – active, closed-loop, with glazed flat-plate collectors – was then estimated
to determine the cost effectiveness of this measure.
Paybacks for domestic solar hot water were close to 80 years and therefore this measure was
not recommended. However, in certain circumstances domestic solar hot water may prove more
attractive. For example, where a solar hot water system has already been in use, adding or
upgrading panels while preserving existing storage and pipes may offer a cost-effective
measure. Also, access to state or federal tax credits and/or utility incentives – currently in pilot
phase – could greatly increase the attractiveness of this measure.
8.8 Custom Projects
8.8.1 UCLA Custom Project 1. Boiler Replacement
This project considers replacing existing old inefficient boilers with new energy efficient boilers.
Existing boilers are old non-condensing boilers. Existing boilers do not capture latent heat from
flue gases resulting in lower combustion efficiency. With condensing boilers 90-98% thermal
efficiency is possible allowing significant natural gas savings. Conventional non condensing
boilers are 70-80% efficient and require return water temperatures at comparatively higher
temperatures. Condensing boilers have a specially designed heat exchanger which allows
boiler to operate at lower return water temperatures and comparatively at higher delta T
(difference between return water temperature and supply water temperature). Operating boiler
at lower temperature reduces heat loss and standby losses.
8.8.2 UCLA Custom Project 2. Chiller Replacement (SRLF, UNEX, Willshire Center)
This project considers replacing existing old inefficient chillers with new energy efficient and
environmental friendly chillers. Existing chillers are old and often require costly maintenance
and downtime. Old chillers do not have good full load and part load efficiencies. In other words
power (KW) used per cooling tons (ton) is comparatively high and therefore provides an
opportunity for electric energy and demand savings. Chillers efficiencies are typically higher or
are often designed for full load which occurs only for few hours per year. Rest of the time
chillers see fewer loads or run at part load. Since cooling load is significantly driven by outside
air and humidity, cooling needs also vary.
Old chillers also use refrigerants containing Ozone-destroying Chlorofluorocarbons (CFC) which
are no longer used in new chillers. New chillers use more environmental friendly
Hydrochlroflurocarbon (HFC) refrigerants. Continuing use of old chillers with outdated
technology and banned refrigerant causes wastage of energy and higher operating costs. Old
chillers require refrigerants which are costly to obtain from a dwindling reclaimed supply. Also it
becomes difficult, costlier and requires longer downtime to obtain parts for old chillers.
Since building depends on local chillers for cooling needs and does not use chilled water from
campus central plant, it is important to have efficient chillers to avoid hefty demand charges.
New efficient chillers provides an opportunity to implement energy conservation measures such
as chilled water supply reset, variable flow, condenser water reset etc without chiller penalty.
With advanced chiller controls it is possible to limit demand and optimize chiller plant energy
use. New chillers with advanced controls provide flexibility in plant operation and effectively use
of plant equipment.
2413.01/Reports/UC SEP Final Report – UCLA.doc 8-18 December 31, 2008
Newcomb | Anderson | McCormick