We had a power outage from 03h00 till 11h00.

In that time my battery volts dropped from 52v to 50.6v. A low amps dB circuit is connected to the inverter. I switched off all the vampire loads at about 08h00.

When the power came back the batteries took 85 mins to recharge @49a up to 53v. Interesting was that the voltage dropped to 52v immediately after the charging stopped. This must be a bms thing as it decreased very rapidly in a countdown mode. 

It took 4.5kWh units to recharge the batteries which equates to R1.25c per hour of inverter time. 

I have a 4kW super infini with 4 x 2000 pylontechs which I use as a backup. No solar panels. 

Some financial considerations :

If I want to go solar I need to go for a R30k panel installation. 

This is the equivalent of 1000 days of power outage or the usage of 8.33 years solar power where I will save 1/3 of my electricity bill. 

Very difficult to motivate financially at the current exorbitant R2. 23c per kwh. 

Edited August 12, 20197 yr by Johandup

Interesting ‘cos for me it’s the batteries that struggle to earn their keep.

My 9 350w panels - R25k maybe - make me about 10-12kwh per day on a sunny or mostly sunny winter’s day.  Monitoring says 250kwh in the last month or R580 of electricity by your price.  (Actually it’s more since for me it comes off the >600kwh coct rate).

Very naive calc says they pay back the capital in 43 months.

Very naive of course since the inverter, install and etc also had to be paid for.  But they are costs whether we talk about a solar PV install or a ups install.  My inverter and yours are hybrid so they do both roles.

It will be more power generated in the summer assuming I have the consumption.

By comparison the batteries, which cost about the same, can only "load shift" say 3.3kwh (70% of 4.8 capacity) so sunshine permitting they can help me get up to a an extra 100kwh in a month or R232.  107 months to earn back the cost with the same quick and dirty sum.

in practice they don’t always recharge fully since there isn’t always "spare" sun in the day.  So then they are less effective.

But the same capital gets me twice the return when spent on panels as compared to batteries.

For me the panels are aimed at saving on the council electricity bill and the batteries are mainly there to help if we get into shedding.

 

 

Edited August 12, 20197 yr by Elbow

This is rather like getting the AA tariffs for using your personal paid for car for work purposes. You will never make enough from traveling to motivates all the costs. Which should include the future replacement btw. And we all know monthly payments go up on new cars...

And any solar component that fails outside the warranty period will upset any financial calculation.

Hmm, and now imagine that there will be a real blackout. Just a small one, 3-5 days. It happens even here in Europe, if there's a bad winter storm or wildfires. Then, 99% of the country is okay, but few thousands people experience a local blackouts.

Since you've already paid a lot for the batteries and inverter, it really makes sense to add just a few panels and get yourself a stable source of the electricity for ever. What's the minimum amount of panels for Infini Super 4KW? I bet that 9-10 panels will be enough. When compared to the price of the equipment that you alredy have, the additional costs are minimal.

It's not all about the ROI, it's about the comfort and security too

 

 

 

5 hours ago, Youda said:

it's about the comfort and security

The only considerations for me.

BUT 😉 being retired, I can pack up my caravan / boswa and go stay elsewhere for that time.

The Kruger National Park sounds like a very good place to be then......

And the 8.8 kWh pylontechs can keep the house going.

but on a more a serious note, when there are week / month long extended outages the whole country will be in the sh#t. And having home solar will not save the day.

And generators can only be used whilst you have fuel for them.

14 hours ago, Johandup said:

If I want to go solar I need to go for a R30k panel installation. 

If you cannot make that back in +-30-40 months of saving on Eskom, I agree, it is not worth it. 

Like recently, I removed the entire EV system on the geyser after 9 years. Spending R30k to replace it all, and I was not interested in a low pressure system, we would never make that back.

It is not like the first time you get EV tubes, when you save a ton.

So I added 4 more panels and forgot about it.

6 hours ago, Johandup said:

And having home solar will not save the day.

3-7 days they say. The trucks cannot deliver due to fuel shortages and because we have a "Just In Time" food delivery system, no fuel = no food.

So having no money, as the banks are down and out of cash, makes little difference in the above scenario.

That "boswa" in the Kruger sounds like a good idea by then. 🙂 

Best keep that boswa stocked then, because that little shop in the camp in Kruger will be out of beer in about 30 seconds. 

Just now, DeepBass9 said:

... that little shop in the camp in Kruger will be out of beer in about 30 seconds. 

True, but just over the borders, you could get some locally brewed beers ... and the jippo's too!

On the other side I can see a hunting season looming.

But then again, the province bordering the Kruger has some very demanding "buyers" who would be forced to go on a "shopping" spree.
(Note: Has nothing to do with anything bar hungry people having to sort out their own. Would not want to be in a city either.)

3 hours ago, DeepBass9 said:

Best keep that boswa stocked then, because that little shop in the camp in Kruger will be out of beer in about 30 seconds. 

Can't buy from them. 

Total ripoff!! 

I have two 12v fridge freezers of 50l and 90l. That's the way to go. 

We buy everything on the outside. 

12 hours ago, Johandup said:

The only considerations for me.

BUT 😉 being retired, I can pack up my caravan / boswa and go stay elsewhere for that time.

The Kruger National Park sounds like a very good place to be then......

And the 8.8 kWh pylontechs can keep the house going.

but on a more a serious note, when there are week / month long extended outages the whole country will be in the sh#t. And having home solar will not save the day.

And generators can only be used whilst you have fuel for them.

If I could choose, I'd vote for being the one who has some solar panels on the roof when SHTF. And after everybody will run away in their caravans, I would collect the lithium batteries from their abandoned homes 🤣