Dehumidifier Shocker!

The Kill-A-Watts monitored the two basement dehumidifiers -- one in the music room, and one by the cat litter.

The music room unit used about the same as previously measured -- about 3.5 kWh over 24 hours.  The cat litter unit, meanwhile, used !!11.85!! kWh.

To put this in perspective: During the summer, we use about 40-50 kWh per day total (which is already a lot for a house of our size).  Of these 40-50 kWh, the cat litter dehumidifier appears to account for more than 10 kWh!

Another way to look at it.  Our Nissan Leaf EV goes about 5 miles on one kWh.  10+ kWh enables

the Leaf to go 50+ miles.  Often the Leaf is driven less than 50 miles per day.  This means that charging the Leaf typically consumes less electricity than running the cat litter dehumidifier.  This will be verified when I monitor the Leaf charging.

To put it yet another way -- the cat litter dehumidifier appears to account for (estimating generously in favor of the dehumidifier) one-fifth of our summer electricity use.  The typical electricity bill in the summer is about $250.  Therefore, this one dehumidifier costs $50 per month from about May to September.

BTW, why is there a difference between the two dehumidifiers?  Here's my theory: the cat litter unit is in an area surrounded by bare concrete walls toward the back of the house where the ground is relatively wet, while the music room unit is in an area with finished walls toward the front of the house where the ground is clearly very dry.  Additionally, the cat litter unit is located by the two sump pump wells, but I doubt they contribute much humidity, however.  As Claudia cleverly suggested, we will swap the two units to determine whether the usage difference is caused by a difference in units, or a difference in humidity in each location.