What the Whirlpool WDFS5118SS costs to run
At 220 kWh/yr, the Whirlpool WDFS5118SS's ENERGY STAR certification puts it about average for its category to run against every other certified dishwasher.
That $41 is priced at 18.8¢/kWh, the average of all 51 state rates this site tracks. Your own state's rate is one click away.
Efficient, or not, for a dishwasher
Against the category average of 232 kWh/yr, this model uses 5.2% less, ranking 98 of 737 dishwashers tracked here for running cost. That average is drawn from all 737 dishwashers ENERGY STAR currently certifies, not an outside number, a $2/year gap from this model at the national rate. Full sourcing is in the sourcing notes.
Right next to it on the list
A rank or two either side of the Whirlpool WDFS5118SS: Whirlpool UDPS5118SP ($41/yr, 220 kWh/yr), then Bosch SHX78CC5UC, SHE78D7*** ($42/yr, 221 kWh/yr).
Same brand, different models
Ranked 2 of Whirlpool's 11 certified dishwashers, this sits between the UDPS5118SP ($41/yr, the brand's cheapest) and the WDTF5024S** ($45/yr, its priciest).
Cost over its typical lifespan
Over the 9-year service life NAHB reports for this category, running the Whirlpool WDFS5118SS costs roughly $372 in electricity, separate from the purchase price.
Is it worth replacing?
Efficient as certified dishwashers go, $41/year is a reasonable baseline if you're comparing what else is on the market.
Worth comparing a few current certified models before deciding.
If you're keeping it
$41/year to run is the predictable cost of the Whirlpool WDFS5118SS; a protection plan covers the unpredictable one, a repair bill.
Where this number comes from
At rank 98 of 737 for running cost, see the dishwasher category page for the rest of the field, or the guide to how much your state matters. The 220 kWh/yr figure is ENERGY STAR's own certification, not a wattage estimate; exact dataset IDs are on the data sources page.