Industry
Commercial electricity for auto repair shops and garages
A small building with a few large machines, so the bill depends on what runs at the same time.
Auto repair shops and garages typically run a low to moderate load factor, which means demand charges and rate schedule fit usually matter more than the supply rate. A small building with a few large machines, so the bill depends on what runs at the same time.
A working-day shape with sharp rises at the start of the day and after lunch, when the compressor, lifts and heaters come on together. Overnight load is lighting and controls.
Illustrative shape, not measured data. It shows the pattern this kind of operation tends to follow, which is why its bill behaves the way it does. Your real profile comes from your own interval data, and it is the only version that can produce a number.
What the federal building survey says
In 2018 the U.S. Energy Information Administration surveyed 6,436 commercial buildings and recorded the electricity each used. These are the surveyed buildings that match auto repair shops and garages, in kWh per square foot per year. Each is a whole building classed by what fills the most of it, so a single tenant space inside a larger building can use more or less.
The survey counts garages and repair shops as vehicle service. It counts dealerships and showrooms as retail, so they are not in this range.
Vehicle service or repair shop
4.6kWh per sq ft a year, median
The middle half of surveyed buildings used 2.4 to 8.7. Nearly all fell between 1.2 and 13.0.
A typical one is 4,800 sq ft. At the median that is about 21,936 kWh a year, roughly $280 a month at the US average commercial price.
106 surveyed buildings Fair
Estimate your buildingSurvey year 2018, so this is the usage pattern, not a forecast. Prices here are today's: the US average commercial price for the 12 months to the latest EIA month. The cost estimator does the same for your own floor area and state.
What drives the load
- Air compressor
- Vehicle lifts and tire and alignment machines
- Shop heating and ventilation
- Welders, a paint booth or curing equipment where present
- Lighting
- Diagnostic and charging equipment, including EV service
The trap this industry falls into
Demand is read as the highest average over a short interval, so what sets it is several large loads running in the same quarter hour: the compressor catching up while lifts, heaters and a booth run at the start of the working day. On many small-commercial schedules there is no demand charge until the account passes a threshold, so a shop can add equipment for years without seeing a change and then be moved onto a demand-billed schedule.
What to actually do
- Find out whether the account is billed for demand and which schedule it is on
- Stagger the start of the compressor, lifts, heaters and booth at the beginning of the day
- Fix compressed-air leaks and check the compressor is sized and controlled for the load it serves
- Check shop lighting hours and controls
- Work out the demand impact of an EV charger or new equipment before it is energised, not after
Which half of the bill to attack
A commercial bill splits into supply, which a competitive supplier can price where a competitive market exists, and delivery, demand, fixed charges and riders, which stay regulated whichever supplier you use. Load factor decides which half is worth your attention, and for auto repair shops and garages the answer is usually clear.
At a low to moderate load factor, the peak is doing disproportionate damage relative to total consumption. Demand charges and rate schedule fit therefore usually matter more than the supply rate, and an operator who switches supplier to chase a lower supply price has left the growing part of the bill untouched.
This is also why a supply quote alone is a misleading answer for this industry. It is priced against the half of the bill that is not the problem.
The mechanics behind this: load factor, demand charges and rate schedule fit.
What we need to give you a real answer
- 12 months of bills
- An equipment list with ratings in kW or amps
- Hours of operation by day
- Whether the account is billed for demand
- Whether the building is shared with another tenant or meter
The item that most often turns a vague conversation into a specific finding is twelve months of peak kW. A single bill shows what you paid; twelve months of demand readings show the shape that caused it, and the shape is where the recoverable money is.
Send one recent bill. We compute the supply, delivery and demand split for your account and tell you which of the levers above is actually worth your time.