A nuclear brick is a small RTG or nuclear reactor built to the form-factor of a brick and controlled by a wireless network. They are to power brick furnaces and heaters for smelting, casting, glass melting and curing, heating of habitats and greenhouses, heating of chemicals, and other thermal processes. A plutonium-powered RTG could last several years but has a much lower specific power than an americium-242-powered nuclear reactor. A 1.6 kg americium core can produce 70 kW of thermal power but this core must be replaced every 80 days of operation. Americium-242 exists on Earth as a byproduct of normal nuclear reactors, but might be produced by a small fast reactor on Mars from native americium-241 if the latter can be found and mined.<ref>
- Genuth, Iddo, 2006, Americium Power Source, TFOT The Future of Things.