I have a friend who is interested in Solar but does not know where to start. I drew up this “getting started” guideline as a basic starting point. Please feel free to correct / add to this content - or add links to articles for further reading:
Guidelines for planning a new solar installation
Most important questions: Determine how important each of these are:
- Energy Independence - do you want to:
- Be completely off grid
- Handle extended grid breakdowns of a full day or more
- Handle long load shedding, when council has an overload - 8 hours
- Handle general load shedding 2-4 hours per day
- What is your night time consumption? Dow you want to be able to carry your lights / fridges, TV overnight?
- Naah - not important if I am off for 2-4 hours during loadshedding
Grid direct consumption:
a) Do you want to save on your variable power bill? How much is it? Have you done some sums?
b) What is your peak power consumption?
c) What is you average power consumption?
What is your time horizon / budget? Are you prepared for a 10 year payback? 5 years?
Generally speaking there will be two possible solutions, each of which can scale from 50% coverage to more than 100% coverage, depending on the budget:
a) Hybrid solar system - with DC battery storage
- More expensive, with 6-12 year payback period - depending on how fast utility prices will rise
- Battery is very expensive - about 30 - 40% of system cost
- Gives overnight / load shedding security by keeping you switched on
b) Grid-tied inverter with no storage
- Much cheaper, with a shorter payback period.
- If you consumption is mainly during daytime hours (A/C / heater / computers / lights) then this works very well to decrease your electricity bill.
- If your consumption is night time biased, this option is not going to work for you.
- You get no backup or overnight power protection.
The third option is to go completely off gird - but generally this is very expensive to do due to high peak consumption that we have all grown accustomed to. Only solar hobbyists with nothing better to do with their money, and survivalist nutcases go this route. Or of course if you can not get on grid at all.
Once these questions are answered, your choices will narrow down and you can investigate the options in more detail. Also, the best method to get to learn your daily consumption is measure it, preferrably with a logging system - something like a Victron Venus GX and a ET112 Energy meter.