Yeah, towels take a little longer, but I only run one load of towels a week, and I take jeans & dockers to work and have my employees wash & press them, so the bulk of my laundry at home is socks, underwear, and T-shirts.
I remember a friend of mine that had a shed with three freezers in it. The shed was heavily insulated with no heating source other then the freezers. You could go out there in the middle of winter and the shed would be nice and warm inside. So he would keep items that couldn't freeze in the shed also. So it served as a freezer and a warm storage unit.
The average temperature in most mines is about 55F, not good for heating. Also, mines can concentrated gasses, such as radon, CO2, and methane which would be poisonous if pumped into a sealed building.
On the supply side, there are on demand hot water pumps. Hit a button at the sink, it draws hot water from the water heater, and returns it down the cold water line. This way you aren't dumping water down the drain waiting for it to heat up.
For the most part, any electrical device will put as much heat into your house as it uses. An obvious exception is things like the hot water heater, with most hot water going down the drain.
In the case of a fridge, the only caveat is that most of them give off their heat from the back of the fridge, so most of this heat goes into heating an external wall. If possible, put your fridge in your house in such a way that it is completely inside your house, on all sides.
I'd like to rant about how dumb it is to place baseboard heaters on exterior walls, instead of interior walls, since a significant portion of that heat goes into heating the wall instead of the interior, but that's off topic so I'll shut up.
We have electric heat also, and in the wintertime we are very liberal about leaving electrical devices (such as the TV or computer) on, however in the summertime we are very careful to run these devices at an absolute minimum.
We also don't run the exhaust fan in our bathroom - we leave the door open during showers to help recover heat and humidify the house. Oops, off topic again.
As someone who worked in the heating & a/c business previously, I can say this... Vents & heaters are placed on outside walls (and usually near doors & windows) for comfort, not efficiency. The installer does not care how efficient the installation is, but is mindful of having to come back and change things if the customer is not comfortable and is unhappy. Because of this, whenever we quoted for a system, we always slightly oversized the system for the house, so the people would be comfortable, and we would not get complaints that "the system is constantly running" (That was a common complaint for heat pumps in the late 80's/early 90's)
Spend a little more on the installation, and you don't have callbacks. I hated having to put off a paying job to go on a free service call.