What have done towards your prep?

[Mortblanc]

Those cheap immersion heaters are a bit sketchy. I had one once and it heated so fast it gave me uncertainty.

They go hot instantly and I mean instantly! If you plug them in and they are not in the fluid already they glow red hot in seconds and start melting the wires and plastic housing.

I always found that in a long term situation just keeping a good sized pot on the fire was enough for daily use with larger volume uses part of the daily lifestyle planning. You know when washup time is near, and bath time. Set it up as you need it and don't try to keep enough to shower on hand 24/7.

We used to stay in long term reenactment camps for 2-3 weeks at a time and acquired some good gear for that. Most of it was enamel ware. I have a couple of enamel canning pots for hot water bath canning that hold about 20 liters. I have one large enamelware coffee pot that holds 9L. We used to keep those near the firepit and they were generally kept warm if not hot.

In those camps, with half a thousand people living at the 18th century level, it was not unusual to walk into a camp and see 4-5 2L coffee pots around the fire at every tent. Coffee was always on the fire. Generally there was some kind of food cooking in every camp so the fires were always going.

The enamelware is much safer than putting zinc on the fire in those galvanized pails. If you ever boil it dry you are releasing poison gas.

I also have a Zodi camp shower that uses a 1# propane canister. It will heat gallons and heat it fast! It does not have to be for showers either. That thing will boil a gallon a minute as it pumps water through the system. It is stingy on the gas too. I have heated water for 15-20 people on one tank using about 3 gallons per person.

SS, you have all sorts of immersion pumps in your greenhouses, why not cobble up a system similar, with an inlet fitting on one end of a copper coil and an outlet on the other. Make the coil as large as the stove will allow. Fit the pump to one end and put both ends into a big pail of water and sit the copper coil directly into the fire?

Circulate the water until the bucket of water is the temp you want.

Between the rechargeable batteries and the wood fire heating the water you could have a nice "on call" system for special events.