In the interest of full disclosure the author is a Director of Maine Energy Systems.
I am often asked what I do about domestic hot water in the summer since my house is heated with a MESys pellet boiler system. The answer is, “I burn some pellets” just as I have burned some oil to create hot water for decades.
The follow-on question is always, “how many wood pellets does it take?” In a single case sample, my own, I have found an answer. Three adults live in my house full-time, one a college-aged son who loves long showers. We have frequent overnight company, including the families of four of our older son and our daughter. We use a washing machine and dishwasher as anyone does, and we’ve made no particular water reduction modifications to our house so our hot water consumption is probably typical for Americans like us.
My system contains an indirect hot water tank, which I keep adjusted to 180F during the heating months. During the non-heating months, I’ve reduced that setting to 120F, so the boiler fires at low level or in “keep alive” mode most of the time.
This summer, since the end of the heating season, I have averaged 20 pounds of pellets/day for the heating of water using my MESys 4000/Janfire system. At $270/ton that places my average daily hot water costs at $2.70, or the cost of a bit more than a gallon of #2 heating oil.
Ideally, I would have solar panels on my barn roof to further reduce combustion of any sort for the production of domestic hot water, but that will have to wait a bit.