The costs
It usually costs $20,000 - $60,000 to go completely off grid. This is triple the cost of staying grid connected and installing solar. There are several reasons why it’s so expensive; First, because of the need for a large battery bank to tide you through the winter months when the sun doesn’t shine very much. Second, because of the need for an expensive inverter/charger to manage your solar generation, power consumption, and generator connection (yes, you will need a generator). Third, because of the dedicated space required for battery storage. And forth, because of the design and installation cost which is much higher than that of the simpler grid connected systems.
Design complexity
An off grid system must be designed correctly. You need to think through all the appliances you will want to run to determine the total daily load that you will need to draw from your batteries. Get this wrong and you could end up running out of power or shortening the life of your batteries prematurely. Off grid solar is not a ‘set and forget’ type of system. You will need to manage your load, be aware of when the sun is shining, and be prepared to maintain your system over the years.
It can’t run everything
Off grid systems have a finite power limit. That limit is set by your battery and inverter/charger size. Unless you install a very large system there will be some things you should not expect to run from off grid solar. These are the types of loads that use a lot of electricity. For example, we advise people not to run an electric oven, dryer, heater, spa pool, swimming pool, heat pump, or charge an EV.