Hybrid System Design Decisions

I hope I’m posting this in the correct forum, if not please point me in the right direction.

Please guide me regarding the correct system/components to choose.

My requirements are:
• Need to power the basics (lights, fridge and freezers, tv, pc, microwave, security system – alarm/electric fence/cctv, small appliances)
• Ability to power geyser, stove/oven, aircon during the day, if/when there is excess or enough power
• Option to not feedback to the grid but consume from there when need be (system must be on and not shutdown when the grid is down)
• Ability to have enough reserve for the basics above if the grid is out for more than a day, which can run over a few days
• According to my statement the daily average consumption is 50kw

Given the current/deteriorating state of the grid together with inconsistent supply due to theft and long turnaround time in repairs. I’m thinking the batteries need to be kept fully charged.
Will this impact the choice in the components I choose? Meaning when the power goes out, I consume from the panels during the day, then from the batteries during the night, the next morning the panels charge the batteries and supply the house.
Is this possible or does it make sense to set it up this way?

When the grid is on, should I or can I configure the system to charge the batteries first depending on how much current the panels are producing, meaning if its cloudy or during winter I’d prefer for the batteries to be charged as quickly as possible.

Space is limited where there is full day exposure to the sun, in the backyard.
The db board is located on a wall that’s next to the driveway, meaning all of the components will not be able to be installed nearby.

All help and information will be highly appreciated!

Many Thanks!!!

The first step is to get to understand your own power usage pattern.
(that doesn’t mean listing your appliances and when you think they’re on. It means actually recording your power usage over a couple of weeks).
The second step is doing what you can do to reduce your power usage.
Third step, What can you do to reschedule loads from nighttime to daytime?

Now that you know these details, you can plan your system and you have already saved yourself over 20K.


Very wise words, however I think the saving if following those steps properly will be a lot more than R20k.

1 Like

If I can add my 50 cents along with the others…

It’s an old bit of advice I first heard about 10 years ago. Whatever you spend on reducing your energy consumption is saved 3-fold on the solar side. You need less batteries, less solar panels, and potentially a smaller inverter. That’s three times :slight_smile:

Back in 2013, LED lamps were still insanely expensive, but that was the first thing we did. You made everything LED. Then you bought a nice energy efficient fridge and freezer, maybe invested in a solar geyser or a heat pump. At that point, some people have already saved so much money that they simply skipped the solar system altogether… of course that is no longer an option, but it is till a good story.

I assume you mean 50kWh (killowatt-hour). Don’t know the size of the house but that is quite a lot. If you can halve that, the solar system becomes a LOT cheaper…


You have indicated that you will have grid power which I have always thought is a good option. However give some thought to surviving without grid power (off grid) and build that capability into your system if possible.

1 Like

Thanks Phil.g00.
That makes good sense.

Thanks Plonkster.
Yes kilowatt-hour.
I suspect the meter, ever since the smart meter was installed it jumped from an average of 30kWh.

Thanks Richard_Mackay.
I have thought about going off grid but that seemed too expensive and the general consensus seemed to indicate that we cannot go completely off grid.
However I’d prefer that