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?
Inverter (DC to AC)
Needs the grid
One of 4 ways to meet this need. Cost, carbon, footprint and rankings are relative to other solutions for the same need, not absolute.
A box of electronics that turns the direct current from batteries or solar panels into the alternating current ordinary sockets and appliances use. It lets a solar system run a normal house. It is also the part most likely to fail and the hardest to repair yourself.
10-15 years typical for a residential inverter; the single most failure-prone link in a PV system per general industry experience
Embodied carbon
Medium
Space / material use
Low
Output timing
On-demand/controllable
Skill to repair
Specialist
Regulation (FR example)
Fixed electrical installations must meet NF C 15-100, and a Consuel certificate is required before a new connection is energised. Grid-connected generation requires an Enedis connection agreement.
Levels are relative to the other options for this need, not absolute. Fewer dots is lighter.
Inverter (DC to AC) (This page) Can I use it? Works in a flat · No rebuilding needed What does it cost me? Upfront cost: Medium · Skill to build: Specialist · Upkeep: Light · Change to daily life: None · Works without the grid: No Choose it if you want a solar system to run ordinary sockets and appliances.
Dual-bus wiring (DC essentials + AC general) Can I use it? Works in a flat · No rebuilding needed What does it cost me? Upfront cost: Medium · Skill to build: Intermediate · Upkeep: None · Change to daily life: None · Works without the grid: Yes Choose it if you want lights and the fridge to keep working even if the inverter fails.
Direct solar power (battery-free direct-PV supply) Can I use it? Works in a flat · No rebuilding needed What does it cost me? Upfront cost: Low · Skill to build: Intermediate · Upkeep: None · Change to daily life: Daily · Works without the grid: Yes Choose it if some tasks can wait for the sun, such as pumping or heating water, and you want no battery to buy.
Solar power diverter / router (surplus-PV to resistive load) Can I use it? Works in a flat · No rebuilding needed What does it cost me? Upfront cost: Medium · Skill to build: Intermediate · Upkeep: None · Change to daily life: None · Works without the grid: Yes Choose it if you want your solar surplus to heat water instead of being given away.
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.