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?

Backup / redundant supply

What runs when the usual supply does not: a long grey week, a grid failure, a broken inverter. The question is which loads have to keep going, not how to power the whole house. The options differ in whether they add stored energy or a second way of making it, and in whether they need fuel bought in.

Solutions

• Backup generator: An engine burning petrol, diesel or propane that drives a generator. It is started when the sun and wind have been too weak for too long and the batteries run l
• Oversized battery bank for extended autonomy: A battery bank sized well beyond the daily need, so it can carry the house through several days without sun or wind. It stores more energy instead of relying on