The sunlight is going to follow a bell curve. Assume 800W at noon, and pessimistically approximate the curve with a triangle. That’s 400W * 12 hours. That’s 4.8 kwh per day.
If your house is provisioned for 900W peak, you aren’t running a furnace, a/c, electric heat, or an EV. 4.8 kWh will go a long way in those circumstances. (It’d handle a fridge or two if you could time shift the power, or got one that’s designed to hold cold over night with no power)
I don’t think you strictly need utility approvals to install balcony solar. Usually, you can either not wire them into the house at all, or have a switch to switch the house between grid and solar. (It’s better to back feed into the grid, but that requires utility cooperation. If properly installed the switch I describe is safe but maybe illegal.)
Legality can be a funny thing. Governments can make anything they want illegal. Here in Argentina it's illegal to import used capital equipment that hasn't been refurbished by the original manufacturer or to import maps that say that the Malvinas Islands aren't part of Argentina. In Thailand it's illegal to step on paper currency because the king's face is on it.
If your house is provisioned for 900W peak, you aren’t running a furnace, a/c, electric heat, or an EV. 4.8 kWh will go a long way in those circumstances. (It’d handle a fridge or two if you could time shift the power, or got one that’s designed to hold cold over night with no power)
I don’t think you strictly need utility approvals to install balcony solar. Usually, you can either not wire them into the house at all, or have a switch to switch the house between grid and solar. (It’s better to back feed into the grid, but that requires utility cooperation. If properly installed the switch I describe is safe but maybe illegal.)