Example of Energy Efficiency Measures(EEMs) Project
ANDERSON UHSD
SPECTRUM ENERGY SUMMARY OF PROPOSED EEM’S PHASE 1 OF A MULTI-PHASE DISTRICT
WIDE PROJECT
New Administration Building Chiller – Since the only campus building used regularly
during the summer was the administration building, a new, 40-ton chiller at the
200 building that provides chilled water only to this building instead of operating
the existing 200-ton main chiller. This allows the main chilled water system, including
chiller, primary pump, condenser pump, and the cooling tower, to be shut down for
two months of the summer. A second aspect of this EEM is to reduce pump energy by
changing the campus distribution system to a variable flow system. Since the chiller
is a constant-flow unit, this would required converting the existing pump system
to a primary/secondary system. The EEM required the following work:
Item 1: New Chiller
- New 40-ton air-cooled chiller
- New 5 HP chilled water pump
- New electrical circuits to the pump and chiller.
- New concrete pad and chiller enclosure.
- New 3” chilled water supply and return piping from the new chiller to the interconnect
points with the existing chilled water piping mains in the 200 building.
- New control hardware and software to interface with the existing DDC system.
Item 2: New chilled water pumping
- Remove existing 40 HP chilled water supply pump.
- Install new 10 HP primary chilled water supply pump to pump a constant flow continuously
through the existing main campus chiller.
- Install new 30 HP secondary chilled water pump to circulate chilled water at a variable
flow rate to the campus. This pump would re-use the existing VFD to vary its speed.
- Modify the existing chilled water piping in the chiller room to adapt it to this
primary/secondary piping scheme.
- Close the bypass legs of most three-way control
valves. The secondary system will have to maintain a minimum flow during heating,
so some 3-way valves will have to be left in place.
Annual Savings $17,205
Item 3: Controls recommissioning
The district currently has all fan coils scheduled to operate on a fixed schedule.
This schedule assumes the worst-case scenario for building morning warmup and allowing
for after-hours work. The proposed EEM modifies the existing software to change
the morning startup time based on optimal start logic. Optimal start logic would
look at how long it actually takes to bring the rooms up to occupied setpoint temperature
then adjust each day’s startup time based on the actual outside air temperature.
It also modifies the fan scheduling to shut down the fans once school is out. The
staff has to hit the “override” button at each room’s temperature sensor to operate
the fan and heating/cooling for after-school hours.
Annual Savings $19,397
Item 4: Lighting-Campus Wide Program
Project consists of partial change out of ballast/lamps in 1,933 fixtures in all
buildings. Motion sensors were installed where appropriate and a Use Factor of .9
and used as a standard and .8 used for high occupancy and/or after-hours use buildings
such as gymnasiums, performing arts and cafeteria buildings. To maintain light levels
at existing levels delamping was ruled out as an option. Determination of extended
hours facility use was from numerous meetings with district site personnel, district
modernization and mechanical consultants and personal observations during day and
night walk-thru’s of the facilities.
Annual Savings $12,162
Item 5: Photovoltaic Solar System
Project consists of the installation of a 245kw solar photovoltaic systems ground
mounted.
Annual Savings $52,896
Item 6: West Valley High – Rate Savings Change
Project consists of a rate change from A-10 to A-6
Annual Savings $16,672
Total Annual Savings: $118,332