Unexpected 25% Jump in School's KW Usage
Unexpected 25% Jump in School's KW Usage
(OP)
I have been invited to a meeting with a local school to discuss an unexpected 25% jump in the KW usage of their monthly High School building bills (last 2 months). The building (classrooms, gym, band hall) was built in 2002, and KW usage has been repeatable over the years, so the 25% jump is extraordinary. They say they have had an increasing amount of "brownouts" in recent months (...although in these rural settings a large number of brownouts from the utility is not at all unusual; this may or may not be connected to the current problem. However, some people at the school swear these brown-out occurrences are much higher.) I do not have many details at the present, but wanted to ask for help concerning this "brainstorming" meeting.
The electric delivery provider (Co-Op) has been involved and has said that they plan to change out the meter to make sure this is just not a metering problem. The electric delivery provider has not to date found any other problem.
I am assuming this initial meeting with the school will result in approval to bring in an electrical contractor to fully check out the electrical supply (after waiting to see if the meter replacement fixes the high KW billing problem).
Any ideas of possible causes to discuss or what would be recommended as a path forward different than the above would be greatly appreciated by me and the folks at the school.
The electric delivery provider (Co-Op) has been involved and has said that they plan to change out the meter to make sure this is just not a metering problem. The electric delivery provider has not to date found any other problem.
I am assuming this initial meeting with the school will result in approval to bring in an electrical contractor to fully check out the electrical supply (after waiting to see if the meter replacement fixes the high KW billing problem).
Any ideas of possible causes to discuss or what would be recommended as a path forward different than the above would be greatly appreciated by me and the folks at the school.






RE: Unexpected 25% Jump in School's KW Usage
RE: Unexpected 25% Jump in School's KW Usage
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RE: Unexpected 25% Jump in School's KW Usage
I once discovered that a new night watchman had been, on his own initiative, adding cold water to our hot water heating system until the 'head' gage way up on the wall stopped rising. ... by which time the system relief valve had discharged an equivalent quantity of heated water down a drain.
The plant manager had noticed a step change in our energy cost that correlated with that watchman's arrival.
Mike Halloran
Pembroke Pines, FL, USA
RE: Unexpected 25% Jump in School's KW Usage
Not so the new electronic meters. I have seen electronic meters fail and over-meter. The utility acknowledged the error and credited the customer with the overbilled amount.
Note, an increase in ambient temperature from just below the A/C cut-in to just above the A/C cut-in temperature will often cause a dramatic rise in the consumed KWHrs.
If you have an electronic meter it may be programmed to record parameters periodically.
I have received from utility metering departments a file downloaded from an electronic meter. It listed:
Voltage per phase,
Current per phase,
Kilo-Watts,
Kilo-VARs,
Power factor.
The readings were at 15 minute intervals over a months time. It is worth an inquiry. If an electronic meter is in use it may be possible to obtain readings. If the meter is not programmed to save parameters you may be able to arrange for it to be programmed. You may have to purchase an internal battery for the meter. The battery is not needed for revenue metering but is needed for the internal clock for TOD metering and data storage.
Bottom line, check the weather records for the month in question to see if the weather has been unseasonably warm. I had to field this issue several times a year when working in Central America.
Bill
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"Why not the best?"
Jimmy Carter
RE: Unexpected 25% Jump in School's KW Usage
I'd also want to know where the brown out was - PoCo side or customer side.
Otherwise The Meeting is going to be speculation about speculation.
Keith Cress
kcress - http://www.flaminsystems.com
RE: Unexpected 25% Jump in School's KW Usage
I'm with jghirst however... As what is likely the single largest load, check into that HVAC. Depending on the size and type of the system, a relatively minor refrigerant loss, an air or water valve in the wrong position, an acess door left open, too-tight or mis-aligned belts, and so on can add up to large costs.
RE: Unexpected 25% Jump in School's KW Usage
RE: Unexpected 25% Jump in School's KW Usage
Voltage regulation is frequently an issue in rural areas due to long circuits, voltage drop, and not enough load to justify the cost of voltage regulators.
Utilities from time to time address low voltage or "brown out" conditions by raising the voltage at the supply end. This often leads to high voltages to some customers during periods when the loads that are responsible for the low voltage conditions are off line.
Investigate whether the utility has recently raised the voltage on your distribution line.
Bill
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"Why not the best?"
Jimmy Carter
RE: Unexpected 25% Jump in School's KW Usage