Low-power computing as a resilience reserve

A suggestion to preserve older computers as strategic reserves leads to a simpler resilience example: the solar-powered calculator. It performs basic calculations for years with little maintenance, very low power demand, and no dependence on a charging network. A phone can do more, but its larger energy demands make it a less durable backup for this narrow task. The example shows why resilient systems may retain small, independent tools alongside more capable technology.