ELECTRICAL
View Building Electrical
Load Summary Chart
Existing Systems
The existing buildings are provided with 277/480V electrical services. Several
of the original buildings are serviced from a common service located on the east
side of the campus adjacent to Receiving. These services are supplied and separately
metered by Salt River Project. The locations of these services and their sizes
versus the location and size of the new buildings planned preclude the use of
these services for the new buildings. New services should be provided for each
of the new buildings.
Basis for Evaluations
The specific requirements for each building will not be defined at this time.
Therefore, for the purpose of estimating building loads and to evaluate the adequacy
of existing building capacity, the following assumptions were considered:
1. 25% of each classroom/lab building will be a "Lab", i.e. science
"type", computer, etc.
2. Every classroom is fully mediated.
Basis for Estimated Electrical Loads
The estimated electrical loads are based on the recently completed Maricopa Community
College projects including the Red Mountain Campus of Mesa Community College.
The electrical loads for various building types are based on the following:
Building Type Total Load @ 480/277V Load @ 120/208V
Classroom/Administration 20 VA/GSF 10 VA/GSF
Classroom/Multipurpose 21 VA/GSF 11 VA/GSF
Classrooms/Laboratories 24 VA/GSF 14 VA/GSF
12.47 kV Electrical Distribution System
Salt River Project (SRP) provides power to the Pecos Campus. An existing 12.47
kV underground lines runs north from Pecos Road up both the east and west sides
of the campus to supply power to the existing buildings. This 12.47 kV distribution
system will have to be extended to provide power to the new buildings. SRP will
require that a loop be provided through the campus to increase reliability. The
drawing on the previous page shows a proposed route for this loop. Once design
work is started, SRP will require review of the proposed design before detailed
design begins. SRP typically provides the conductors, manholes and 12.47 kV terminations.
CGCC will provide the trenching, conduit and equipment pads.
It should be noted that the new Wellness Center is proposed to be located above
two of the existing 12.47 kV feeders on the east side of the existing campus.
These two feeders will have to be relocated.
Scope of Work & Related Costs
- New Buildings: As stated above, new buildings will be provided
with new 277/480V service entrance sections supplied directly from the APS 12.47
kV distribution system. Lighting and mechanical equipment will be supplied from
the 480V distribution system and 120/208V loads will be supplied through a system
of 480-120/208V transformers and panel boards.
- Site Electrical Utility Modifications and Additions: It
is estimated that approximately 3,500 linear feet of trenching and conduit will
be required to extend the existing underground 12.47 kV feeders, complete the
loop required by SRP, and install conduit to the new buildings. In addition
approximately 6 new manholes will be required. The cost for conduit, trenching
and equipment pads is approximately $100 per linear foot so that total cost
for underground work is $350,000. Since all of the buildings are new loads on
the SRP system, fees to provide service by SRP should not be significant, and
no allowance is included here.
