3.5.1
Adequacy. Determine the capability of the electric utility company
to furnish electric power, of the required characteristics, to meet the
immediate estimated demand. The capability of the utility to meet the demand
under mobilization conditions should be determined on the best basis
available. Ascertain whether or not the utility has enough construction in
its program to meet the loads anticipated for the next 5 years.
3.5.2
Reliability. Investigate the history of outages of the
contemplated utility company to determine if it can provide the degree of
reliability required by the particular installation. The investigation
shall include the following items:
a)
A 5-year history of service outages in the area, including:
(1) The time and date of each occurrence
(2) Duration, time, and date of each restoration
(3) Cause
(4) Steps taken to restore service and
(5) A probability analysis showing the expected number of
outages of 1 minute, 5 minutes, 10 minutes, 30 minutes, and 60 minutes.
b) A one-line diagram of the supplier's system, showing the
location of all switching equipment, circuit breakers, relaying, and similar
components.
c) A short circuit study of the system, including interrupting
capacities of all switching equipment, time constants, and short circuit
currents for both existing and expanded facilities in the area.
d) Voltage regulation, nominal voltage, and normal operating
voltage of supplier's facilities.
e) Climatic and other physical conditions prevailing in the area
and on the system that may affect the reliability of service. Some utilities
will only supply a minimum of data for items a) to c), and evaluation may be
necessary using data available from other military installations in the area.
3.5.3
Rates. To take advantage of the lowest available cost of electric
energy, compare electric energy rates with estimated maximum demand and
consumption. Compare the estimated demand block with prices per kilowatt-
hour of other customers served by the same utility company. Choice of either
primary or secondary connection shall be based on selection of connection
charges and rental of company equipment that provide the maximum advantage to
the Government. An analysis of rates shall be based on the company's
complete tariff covering all types of services. This review will entail
comparison of several tariffs that are available on an alternative basis, as
well as the Contractor's general rules and regulations that modify the
tariffs.
3.5.4
Primary Service Right-of-Way. The supply company should provide
the right-of-way for all of its electric lines up to the Government property
(refer to MIL-HDBK-1004/2, Power Distribution Systems).
27
Previous Page
