What the Giant GTHPCO-45 1**+GTXST-50S 1* costs to run
ENERGY STAR certifies the Giant GTHPCO-45 1**+GTXST-50S 1* at 923 kWh/yr, cheaper than most models in its category to run for its category.
That $174 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 electric water heater
Against the category average of 1,105 kWh/yr, this model uses 16.5% less, ranking 219 of 596 electric water heaters tracked here for running cost. That average is drawn from all 596 electric water heaters ENERGY STAR currently certifies, not an outside number, a $34/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 Giant GTHPCO-45 1**+GTXST-50S 1*: Giant GHPCO-45 1**+GXST-50TTTP 1** ($174/yr, 923 kWh/yr), then Giant GTHPCO-45 1**+GTXST-50S 1** ($174/yr, 923 kWh/yr).
Within the Giant lineup
Ranked 4 of Giant's 13 certified electric water heaters, this sits between the GTHPCO-45 1**+GTXST-50LBTTP 1* ($172/yr, the brand's cheapest) and the GTHPCO-45 1**+GTXST-66TTP 1** ($252/yr, its priciest).
Cost over its typical lifespan
NAHB's Study of Life Expectancy of Home Components puts a typical electric water heater's service life at 11 years; run the Giant GTHPCO-45 1**+GTXST-50S 1* that long and it costs about $1,909 in electricity, on top of whatever it cost to buy.
Weighing a replacement
Efficient as certified electric water heaters go, $174/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
At $174/year just to run, a electric water heater is worth protecting against an unplanned repair bill on top of that.
Where this number comes from
Two sourced numbers, nothing modeled: ENERGY STAR's certified kWh/yr for this exact model, and EIA's published state electricity rate. Ranked 219 of 596, the Giant GTHPCO-45 1**+GTXST-50S 1* sits in the middle of the electric water heater category, see the guide to why your state changes this number for the other half of the math.