It is hard to have total solar power unless you also use little power, and you must have “deep cycle” batteries that can provide current at a constant voltage until they’re nearly exhausted.

My suspected answer to your question: Electricity costs a lot in Dominica because so much of it is generated using fossil fuel and Dominica is not yet getting the benefit from fuel from Venezuela at a no-middleman discount, and also because electrical production is in the hands of a monopoly.

But now comes the real question. WHY are electric rates so much higher here than elsewhere? I hope someone will enlighten me.