Lowtech Graph lists low-tech options for every need of a home. Here you can compare them, find tutorials to build them, and link them together into a circular system. Why low-tech?
Pressure canning / autoclave sterilization
Passive
One of 3 ways to meet this need. Cost, carbon, footprint and rankings are relative to other solutions for the same need, not absolute.
What your site needs
Wood-fired variant needs an existing chimney flue connection
A pot or chamber that heats sealed jars of food under pressure, following set times and temperatures. The pressure lets the jars get hotter than boiling water, which kills everything that would spoil the food, so cooked dishes and vegetables keep for months at room temperature. The simplest way is a pressure canner on the hob, bought rather than built: that is the version rated here. A pressure cooker in a home-made insulated jacket, heated by a 100 W bulb, runs on very little electricity, even solar; a large one on a pellet burner does big batches.
Levels are relative to the other options for this need, not absolute. Fewer dots is lighter.
Pressure canning / autoclave sterilization (This page) Can I use it? Works in a flat · No rebuilding needed What does it cost me? Upfront cost: Medium · Skill to build: None · Upkeep: Light · Change to daily life: Occasional · Works without the grid: Yes Choose it if you want cooked dishes and vegetables to keep for months at room temperature.
Solar dryer (dehydration) Can I use it? Works in a flat · No rebuilding needed What does it cost me? Upfront cost: Low · Skill to build: Basic · Upkeep: Regular · Change to daily life: Occasional · Works without the grid: Yes Choose it if you want fruit, vegetables or herbs to keep for months with no running cost.
Boiling-water bath preserving (pasteurisation) Can I use it? Works in a flat · No rebuilding needed What does it cost me? Upfront cost: Low · Skill to build: None · Upkeep: Light · Change to daily life: Occasional · Works without the grid: Yes Choose it if you want fruit, jams and pickles to keep for months with just a large pot.
We don’t list sizing or quantities, as the yield of each technique depends on the quality of its build. The catalogue compares options but doesn’t dimension them. Regulatory notes are indicative, with a French example, and need to be confirmed locally.