Electric Meter Saga
In January, my electric bill rose by 40% (88 kWh) which I found odd for my small apartment with gas heat, hot water and stove with no laundry. The increase is the equivalent of something drawing 120W 24/7 for the entire month which seemed unlikely for the electric devices I had, mainly: fridge, water pump, dishwasher, lights, TV and chargers. This is the story of how figured out what happened.
I started with the fridge, my largest appliance. I figured I’d install my Kill-a-watt and monitor it, but in pulling it out I also figured I’d go ahead and clean it. The amount of debris on the radiator fins (pictured here) was dismaying and certainly affecting efficiency, but it was not something that would have changed quickly and therefore couldn’t be the culprit for the spike. 24 hours later, my fridge had consumed just 1.2 kWh.
A day later I was sitting at my desk and had a moment of panic. Recalling that I had cranked up my hot water heater in January, it dawned on me that I could be a complete idiot and that perhaps I had an electric hot water heater and a terrible memory. Thankfully my memory served me right, and I do in fact have a gas hot water heater, so this too was not the culprit of the spike.
As an aside, all the while I had an email dialog with my Dad, an engineer, who chuckled about my concern over a “normal blip” and suggested I move on. He’s a guy who’s been recording his car’s mileage, gallons pumped and MPG in a little notebook for 30 years, so I was amused but not discouraged.
At this point, not knowing what else to do, I decided to compile a spreadsheet enumerating all of the electric devices in my apartment alongside their wattage and estimated usage. After an hour or so of inspecting labels to get accurate wattage, I had 28 items and a resulting estimate of 286 kWh. I patted myself on the back for a job well done, since my 5-month average was 240 kWh, so this was pretty close given all the assumptions I made about usage. Later, this became the source of a good laugh. (You can view my electrical devices spreadsheet here.)
Two days had now passed and I was eating me up inside to accept that I had somehow used 88 kWh worth of electricity from increased lights, TV, charging and dishwashing. Or worse, I had a short or something that I needed figure out fast! A few days had elapsed since my meter was read, so I went to source, to see how much I’d consumed since. Impossibly, my meter read tens of thousands of kilowatt hours different from the reading only a few days before. I concluded I must be crazy, but after spending a few minutes watching “How to read an electric meter” Youtube videos, I determined I was not in fact crazy. So I went back down to the meters and checked the readings on the others. To my amusement, the meter for another unit read just a few kWh different from my days-old reading, so I noted the meter number and checked my bill. Lo and behold, my account was being billed for that meter, which was not the one labeled for my unit.
I’d solved it! Or had I? I’ve seen labels wrong before, so still not satisfied, I flipped the master switch for the meter labeled for my unit. My wife confirmed she was left in the dark. So I had in fact solved it: wrong meter! As it turns out, our meters had been swapped (only the last digit is different.) The reason for the laughs after my spreadsheet, was that my satisfaction about estimated usage being close to actual turned out to be completely meaningless!
When I signed up for my account a few months ago, there was a good deal of confusion between me and the utility. I was using the legal/postal unit numbers (1F, 1R, 2F, 2R, etc) and they were using what they had (1FF, 1FR, 2FF, 2FR) and we eventually settled based on the name of the previous owner. I assumed the tragically confusing utility numbering was just the work of some cruel customer service representative.
As far as I know, this has been backwards since the building was renovated in 2006, so it’s surprising it took 10 years to discover. However, the units are identical in square footage, appliances and lighting, so in the non-AC, non-space heater months, usage is probably nearly identical. In summer, if one unit used window AC and the other didn’t, the latter probably got a shocking bill for a month or two, but then when the weather cooled, forgot all about it. In winter, a space heater isn’t required. So, I guess, no one noticed.
That is until one month ten years later, someone’s space heater used 88 kWh of juice and I got stingy over $20. (I did confirm with them it was a space heater.) Eversource is coming Friday to “fix the glitch.”
Appendix I: Energy Efficiency
Cleaning the evaporator on your fridge saves juice, as a dirty coil can potentially reduce efficiency by as much as 30%. The dirt both reduces the heat transfer coefficient and surface area of the evaporator, which in turn requires the condenser to run more, which in turn creates more heat and reduces the temperature differential in the system. (See Newton’s Law of Cooling.)
I reduced my consumption by around 26 kWh per month by replacing 8x 65W incandescent floodlights with the equivalent brightness 10W LED bulbs. They cost me $29, so it will take about 5 months to break even where I live (26 kWH/mo * $0.23/kwh = $5.98/mo)
My gas furnace heats water that gets circulated by an old electric pump that draws about 175W peak. A high efficiency Taco 007e replacement draws only 44W, and costs only $15 after a MassSave rebate.
Various folks reminded me to unplug chargers and other phantom draws even when idle.