Solar panels on a tiny house roof can run the lights, a fridge, a laptop and the water pump. They can't run heating, hot water and cooking as well. So going off-grid starts by moving those three to wood, pellets or gas. That one decision matters more than the size of your solar system.
On the gridOff the grid, on our houses
HeatingElectric heater or heat pumpWood stove (Salamander Hobbit, 4 kW), which needs no electricity at all, or pellet stove (La Nordica Luisella, 2.4 to 4.4 kW), which uses 27 to 34 W while it runs
Hot waterElectric water heaterGas tankless water heater: hot water on demand, for as long as you shower. An electric tankless heater needs a 15 to 20 kW connection, which no off-grid system delivers.
CookingInduction cooktopGas cooktop with two burners
ToiletFlush toilet and sewerComposting toilet (Separett Tiny), with no water and only a small fan, or gas incinerating toilet (Cinderella Freedom), which needs only 12 V
WaterMains water and drainRainwater with filtration (a 1 250 l tank in its own shed), or a 210 l fresh water tank, plus a 105 l grey water tank on wheels