Turn the Printed Running Cost Into Dollars a Year

Pick one electricity rate and cite it, then multiply

A kilowatt-hour figure or a wattage is only half of a cost. The other half is a price per kWh, and the EIA publishes one every month: for July 2026 the residential average across the US was 18.31 cents per kWh, up from 17.45 cents in July 2025, listed as a preliminary estimate in Table 5.6.A of the Electric Power Monthly. That edition was released on September 24, 2026 and the grapher serves no older one, so a rate taken from it is dated; the next release lands on October 23, 2026. State rows run from 12.72 cents in Louisiana to 48.00 cents in Hawaii, so a reader with a bill in hand should swap in the rate printed there.

Running costs arrive from makers in four shapes. A kWh-per-year figure is a finished equation waiting for a rate. A wattage is an unfinished one that needs hours of use the buyer has to supply. A consumable with a price and an interval is already in dollars and only needs multiplying by twelve months. A subscription is the simplest of all, because the maker has done the annualizing. The refrigerator, the microwave, the flosser and the sleep clock land in four different shapes, and the exercise is to notice which term is missing before calling the number small.

The refrigerator: IKEA prints 362 kWh, and the rate moves the answer by $15

IKEA's listing for the $749 LAGAN refrigerator reproduces the federal EnergyGuide data: an estimated 362 kWh a year, an estimated annual cost of $51, and a $49 to $70 cost range for models with similar features. Dividing $51 by 362 kWh gives the rate the label assumed, 14.09 cents per kWh. At the July 2026 residential average of 18.31 cents, the same 362 kWh costs $66.28 a year, which is about 8.9 percent of the price tag every year the fridge runs.

The label's $51 is not wrong so much as dated: a buyer on a New England or Pacific-coast bill near 28 cents should expect roughly $101 a year from the same 362 kWh, and a Californian at 33.61 cents about $122, closer to a sixth of the price than a tenth. This is also the printed figure that lets a shopper compare two refrigerators on cost of ownership without guessing usage, because a fridge runs all year regardless of habit. If a competing model prints 300 kWh, the saving at 18.31 cents is $11.35 a year, and a price premium larger than five or six times that has to be justified on something other than electricity.

How many years to multiply by is a document question, and IKEA's documents do not agree. The warranty page names only TILLREDA as falling outside its 5-year limited warranty, while the kitchen warranty brochure linked from it says TILLREDA and LAGAN appliances have a two-year limited warranty. The refrigerator's manual gives five years from purchase and then narrows it: LAGAN appliances bought before May 1, 2026 carry two. IKEA's listing prints both at once, a five-year feature line and a two-year warranty sentence in the description. Two years is $132.56 of electricity and five is $331.41, so the window is worth settling with the store before buying, not from the paperwork in the box.

The microwave: a wattage needs your minutes, and the filter has no price

IKEA's page for the $299 LAGAN over-the-range microwave states 1000 W of microwave power; the manual gives the figure a bill needs, 1500 W of required AC input at 13.5 A. Microwaves carry no EnergyGuide label, so there is no kWh-per-year figure to multiply. What can be computed is a rate per hour of cooking: 1.5 kW at 18.31 cents is 27.5 cents for every hour at full power. A household that averages ten minutes of full-power use a day would log about 91 kWh a year, or $16.71; one that averages three minutes would log about $5. The hours are the buyer's input, not IKEA's, and the fan and cooktop light add a draw the maker has not quantified.

The second running cost is a consumable with an interval but no price. The manual states that the charcoal filter used in recirculating installations should be changed every 6 to 12 months depending on use, and directs owners to order it by telephone under service part number 12270000008304. IKEA's page prints no cost for that part, so the filter line is one or two orders a year at a figure only the service line can supply. A buyer venting the hood outdoors avoids the filter entirely; one recirculating over a stove used daily should phone for the price before treating $299 as the whole cost.

The flosser: $14.99 a year in tips, and electricity that rounds to a cent

Waterpik's WP-580 lists at $99.99 with four tips in the box: two JT-450E Precision tips, one OD-100E Orthodontic tip and one PS-100E Plaque Seeker tip. The maker's tip pages give both halves of the consumable equation. The JT-450E costs $14.99 for two and is to be replaced every six months, so one person using it daily needs two a year; the pair in the box covers year one and every year after that costs one $14.99 package. The OD-100E and PS-100E also cost $14.99 a pair but carry a three-month interval, so a wearer of braces or bridgework who uses one of those as the daily tip needs four a year, two packages, $29.98.

The electricity line is the smallest number on this cost sheet and is worth computing once so it can be ignored afterward. Waterpik states a 4.86 watt-hour rechargeable cell and up to four weeks of use per charge. Thirteen full charges a year is about 63 Wh, or 0.063 kWh, which at 18.31 cents is $0.0115, before whatever the charger loses on the way. Even at ten times that draw the yearly cost stays under 12 cents. For this product the tip interval is the cost line and the plug is not, which is the reverse of the refrigerator, and a buyer choosing between a cordless and a countertop flosser can leave electricity out of the comparison.

The sleep clock: the plan is priced, the power draw is not

Hatch sells the Restore 3 at $169.99 and prints the plan terms beside it: 30 days of Hatch+ included, then $5.99 a month or $59.99 a year, cancelable at any time, with the FAQ confirming that the device works without a subscription. Annualized, the monthly plan is $71.88, the annual plan $59.99, and opting out is $0. Three years on the annual plan come to $179.97, more than the clock itself; three years on the monthly plan come to $215.64. Anyone after the 2,500-title library is buying software on a hardware deposit, and anyone after a sunrise alarm and the core sounds is buying a $169.99 object with no second line.

What Hatch does not print is a wattage. Hatch's Restore 3 page lists dimensions, a weight of 1.27 lb and a power cord in the box, but no figure for what the device draws while lit as a bedside lamp or playing sound through the night. For a device that is plugged in for eight hours every night, that is a real gap, and the gap is left open rather than filled with an estimate: the electricity line for the Restore 3 is unknown from Hatch's material. The plan is therefore the only running cost the maker has quantified, and the setup screen where the trial converts into a renewal is where that number gets decided.

When the multiplication should stop the purchase

Skip a refrigerator purchase on price alone when the kWh figures differ by more than the price does. At 18.31 cents, each 100 kWh of yearly difference is $18.31, which is $36.62 across the two years the warranty brochure gives a LAGAN appliance and $91.55 across the five its own manual gives one bought from May 1, 2026; a cheaper fridge that prints 150 kWh more than a dearer one has given back most of its discount on either window. Skip the microwave's charcoal filter question only if the hood vents outdoors; a recirculating installation with an unpriced filter is a cost that has to be phoned for before it can be budgeted.

Drop the method for products whose running cost is dominated by a term the maker has not published. A sleep clock with no wattage and a microwave with no hours are both cases where the buyer supplies the missing number, and a supplied number is an assumption, not a finding. Write down which term you assumed, keep the printed terms separate from the assumed ones, and do not let a small printed figure, like a flosser's one cent of electricity, stand in for the larger unprinted one beside it.