Good day all.

I'm new on this forum and firstly thanks so much for the wealth of info that you guys have on here. Currently I'm in a confused state as I have about 3-4 systems in my head that I want to start off with. Hopefully the people on here with the systems and expertise can assist me. 

At the moment it's only myself and the wife in a 2-bedroomed townhouse type of dwelling. Main bedroom has an inverter aircon which I use during our summer nights as I cannot sleep without it. The other room we turned into an office x 2 laptops and my gaming PC, multi-functional printer which we use mainly in the evenings when we are back from work. My wife uses her straightener and hair dryer every morning for about 5min each simultaneously. In the lounge we have a soundbar and 55inh led tv. In the kitchen we have a microwave, Double door fridge, toaster (don't use it as often), air fryer (also may be used once in two weeks), Gas stove which we use to cook and boil coffee on, the element is electrical. Geyser is a gas geyser as well. The Garage has Front loader and dishwasher (Used daily), Deep freeze and Tumble dryer (Used only in the winter when the washing piles up). All my appliances I purchase I look for the most energy efficient products available, so most are A+ rated and above. We use about 10-15 units per day. Our domestic lady comes in x 3 days per week, she then uses the iron and hoover during the daytime. 

So, we also stay in a town with its own loadshedding as our infrastructure is shot and during winter, we sometimes have days without electricity. I currently have an 8kw Turner and Morris generator which we use as needed during loadshedding and power outages, fuel is costing me a lot each month running this during evenings and our unplanned outages. 

So, I want to start building a back-up system which will get us through loadshedding firstly and then start to work on more battery capacity and panels. Currently my work is renting the place for me, and I basically pay no rent, the only problem with that is no panels are allowed on the roof. Thus, panels will be last as I would have to build stands for them in the erf.  

My initial budget is around R65-R70K, but can be stretched a bit for a second battery to around R80k.

Systems I was thinking of: 

1) Sunsynk 5kw with x 1 Felicy Solar 8.7kw Battery or even 12.5kw (New) (R70-R80K)

2) Luxpower 5kw with x 2 Dyness/Shoto 5.1kw batteries (R72K)

3) Kodak 6.2 OG-Plus with x 2 Hubble 5.5kw batteries (R83k)

These are estimates I have taken from websites and added about R6k each for installation and sundries.

Thanks any help will be appreciated.

 

There's two measurements that will help here, and you have one - usage per day. You should also look at peak power. Say the microwave and hairdryer and dishwasher are all on that same time. That won't persist for long, but it may be enough to pull more than the inverter can handle, and that's why you need to think about this. Throw in the kettle or air fryer for good measure. See how things can pile up?

My inverter is rated at 4.6 kW, which sounds like a lot if you say it quickly. And it can handle bursts up to 50% higher for 10 seconds. Plenty? Well if the heat pump is running, the kettle is turned on and the dishwasher hits the right part of its cycle (the part where water gets heated) then the system is close to tripping. If you're making breakfast and you decide to use the toaster or the microwave, or those three big loads run simultaneously for long enough... The trip doesn't happen often, and when it does, the inverter resets IF there is grid or sufficient PV. In the dead of a load shed night, we would be toast (pardon the pun).

Also look at what the batteries can handle. They all have a maximum current that they will allow. So sometimes they can be a constraint too. If your inverter demands more than the BMS will allow, then, again, you get a trip.  Also having batteries that you can charge quickly can come in handy.

So do the sums and understand your requirement a bit better. Consider splitting the DB so that only the circuits you MUST have are backed up. That reduces the chance of an overload. Or buy components that can handle more load.

Since you can go for days without power, consider going big on battery, don't get rid of that generator, and consider inverters that will integrate with the generator. It is easy to be mostly OK, most of the time, but here's another thing to imagine - three straight days of overcast weather. So you may need the gennie as a last resort.
 

Thanks for the info Bobster, I took a look at some of the specs on the inverters and batteries and seems like all of them would work for me, as long as I have x 2 Dyness if I take that package. I'm agreeing with you on starting with a bigger battery bank, the quote I received back was a little more than anticipated as it seems the hubble batteries are a bit more expensive now days. So now my option 3 the Kodak 6.2 and Hubble just shot up a lot in price. Has anyone paired a Kodak inverter with Dyness/Shoto batteries? I see Hubble also rates 100% DOD at 3000 cycles and 50% DOD at 6000 cycles, where some others like the pylontech gives you 6000 cycles at 95% DOD. Taking into consideration that x 3 Pylons US3000C will cost me around the same price as x 2 Hubbles, would that not be a better option and like I mentioned earlier, maybe even Dyness or Shoto which is substantially cheaper.

Bobster Luckily, I got it right to train the wife to only use one big ticket item at a time so we will easily manage with a 5kw Inverter and 5kw battery, we are not planning to run everything at once while we loadshed. I'm just trying to get as much bang for my bucks and trying not to rebuy a new inverter 3 years down the line, because I wanted to save a few ZARS now.

I don't mind digging a little more into the savings now, I want to have at least 10kw of Battery back-up with a nice inverter. The 6.2 just gives me that little more peace of mind that we will buffer the inverter more as we will not be potentially straining it as much and my local installer supplies it to me. I'm all for supporting local in our small town, the next step would be the Sunsynk then, but I will not be using the full potential of it until I get PV.  

Thanks once again for all the input.

9 hours ago, Brangus said:

Has anyone paired a Kodak inverter with Dyness/Shoto batteries?

I'm running a Kodak 5.48 and a shoto battery and they work great together. There is no direct BMS-Inverter comms, but that can be solved with solar assistant and you will get monitoring at the same time.

When looking at solar it is wise to look into the future.

I have a gasgeyser and is considering to add an electric geyser in front of it as the price of gas is becoming too high. Supply will become an issue as the refineries have closed down.

I have 6370 watts of solar pabels installed split between east west installations.

At 07h00 I get 1000 watt already. Now in Oct I get maximum 75% from the installed solar capacity - which is fine for running my equipment seperately. Intelligent db’s are still not available so it is up to a human to do the switching. 
With 9600w pylontechs installed it compensates for increased demands during the day. I am using 6000w loads comfortably as long as I know the batteries will be fully charged by sundown. I have a 8kw inverter.

At night I have a constant load of 300w for security lights, electric fencing and alarm. 
In the morning I end up with batteries at 43% soc.

There is no such thing as overinvesting in solar with the way Eskom is going. In 10 years time you will be grateful for the extra money you’ve spent initially. Solar panel prices have increased by 50% over the last two years.

A recent quote for 7 x 455 panels installed was R35000 😕

Without more detail this sounds on the high side. A few quotes I have seen puts the figure at R800-R1000 per panel for installation.

A few months ago I bought a 480W at below R6 per watt which was a very good price. I would not think panels went up nearly that much if comparing like for like. Yes the very latest tech and high output will be at a premium. The same with the latest model of new wheels to get you from point A to B.

I wonder if some of our members in the know can  shed light on why when you Google you find this ad. When you follow the link this price is for a 100W panel. Who is at fault?

Edited October 20, 20223 yr by Scorp007

I bought my panels from the powerforum store and compared current with last purchased price.

You only want to buy from reputable stores - there are many fly-by-night operators on the web. Beware of them.  A quick search will bring up many issues relating to this. 

Okay, so I opted with the Kodak OG Plus 6.2 and 1 Hubble 5.5kw battery, I will be buying the second one very soon (within the next month or so and then a third hopefully before end of December). As I will only be doing battery back-up for the next year, it suited my needs best and as soon as I get the second battery, I think all should be well for a long time. I saw a similar system being installed this weekend at my friend's house and it ran flawlessly during Saturdays loadshedding, that's how I decided on the decision. Thank for all the input and I will post pictures once it is up and running. 

Installation completed, have not had loadshedding as yet. Interesting our load runs between 115w and 240w on idle, I thought it would be a bit higher. Next up one more hubble battery by the end of this month. 

I'm using the watch power app currently.