One year on, was the investment worth it?

[RichardZA]

Hi all

An update one year on. Please read my original post here: 

 

A reminder of the setup

• 8kW Deye inverter

• 18 x 540W JA Solar = 9720W 

• 3 x 4.8kW LifePO4 (80% DOD) 

• 4 solar geysers(!!)

The 4 solar geysers definitely would affect the performance of the solar system as I need less electricity production to heat water, so please bear this in mind with the stats. In retrospect, I would not have purchased the solar geysers, panels are far more versatile and with proper load management a much better deal in my opinion

4 Solar Geysers	R76,253.34
Solar Panels, Inverter, Batteries	R212,000.00
	R288,253.34

For the sake of this comparison I’m going to leave out the solar geysers. I'm assuming they "break even".

I’m also going to assume an interest rate of 9.75% over the full year (can’t be bothered working it out properly) and likewise I’m going to assume the current electricity tariff over the year.

Due to the tiered pricing it’s hard to calculate the exact price per KWh, so I’m using City Power Block 2 as a calculated guess (most of the electricity would be saved within this block), so my rate is R2.31 per KWh (incl VAT).

The solar system cost R212,000.00. The interest on this is R20,689.50.

The production of 10093W @ R2.31 per KWh = R23,361.31

Net gain: R2,671.81

There are a few factors that have prevented me doing better than this. The first is my family is not keen on lifestyle changes and I’ve also got a little more lazy with this over time. Secondly load shedding and other power outages has led me to be super conservative on the battery - I don’t let it go under 40% overnight for instance, so I've been not utilising my full production overnight. Thirdly, we just don’t use a lot of electricity during the day, and seem to use a lot at night (see point #2 lifestyle changes).

The positives have been amazing. I’m not sure how people survive load shedding without a solar system. I’ve loved every minute of owning this system and recommend people take any spare cash, any money in their mortgage, heck anything they can find, and buy a solar system, the payback will get better every year with increasing electricity prices and the lifestyle benefit is incredible. If you work from home, it's essential.

My break even if I make NO adjustments to lifestyle, interest rate remains constant and electricity price rises 9% a year, is in 11 years, assuming no maintenance costs. My guess is there will be some maintenance costs that may shift the payback to 13-14 years (the compounding effect on even a small net gain is amazing!). I don't really care how long the payback is, the lifestyle benefit and the carbon offset are enough for me to say this is better than the money sitting in the mortgage.

Edited October 22, 2022 by RichardZA

[TimCam]

Yip, for myself and family the ROI is absolutely irrelevant. The saving on power costs and ignoring all load-shedding (power independence) is what is important.

Like you, I am enjoying my SunSynk 8.8 kW inverter, 2x Hubble AM-2 5.5 kW batteries, and 20x Canadian Solar panels.

[Antonio de Sa]

14 minutes ago, RichardZA said:

Hi all

An update one year on. Please read my original post here: 

 

A reminder of the setup

• 8kW Deye inverter

• 18 x 540W JA Solar = 9720W 

• 3 x 4.8kW LifePO4 (80% DOD) 

• 4 solar geysers(!!)

The 4 solar geysers definitely would affect the performance of the solar system as I need less electricity production to heat water, so please bear this in mind with the stats. In retrospect, I would not have purchased the solar geysers, panels are far more versatile and with proper load management a much better deal in my opinion

4 Solar Geysers	R76,253.34
Solar Panels, Inverter, Batteries	R212,000.00
	R288,253.34

For the sake of this comparison I’m going to leave out the solar geysers. I'm assuming they "break even".

I’m also going to assume an interest rate of 9.75% over the full year (can’t be bothered working it out properly) and likewise I’m going to assume the current electricity tariff over the year.

Due to the tiered pricing it’s hard to calculate the exact price per KWh, so I’m using City Power Block 2 as a calculated guess (most of the electricity would be saved within this block), so my rate is R2.31 per KWh (incl VAT).

The solar system cost R212,000.00. The interest on this is R20,689.50.

The production of 10093W @ R2.31 per KWh = R23,361.31

Net gain: R2,671.81

There are a few factors that have prevented me doing better than this. The first is my family is not keen on lifestyle changes and I’ve also got a little more lazy with this over time. Secondly load shedding and other power outages has led me to be super conservative on the battery - I don’t let it go under 40% overnight for instance, so I've been not utilising my full production overnight. Thirdly, we just don’t use a lot of electricity during the day, and seem to use a lot at night (see point #2 lifestyle changes).

The positives have been amazing. I’m not sure how people survive load shedding without a solar system. I’ve loved every minute of owning this system and recommend people take any spare cash, any money in their mortgage, heck anything they can find, and buy a solar system, the payback will get better every year with increasing electricity prices and the lifestyle benefit is incredible. If you work from home, it's essential.

My break even if I make NO adjustments to lifestyle, interest rate remains constant and electricity price rises 9% a year, is in 11 years, assuming no maintenance costs. My guess is there will be some maintenance costs that may shift the payback to 13-14 years (the compounding effect on even a small net gain is amazing!). I don't really care how long the payback is, the lifestyle benefit and the carbon offset are enough for me to say this is better than the money sitting in the mortgage.

In my case I invested a bit under 100 K in my system 13 month ago, 2 X 5000 KVA inverters, 12 X 410 W panels and 1 X 5 Kw battery. It powers my all house. I keep track of all my consumption and how much I purchase from municipality. so far, I've saved over 12 K and most importantly no more load shedding. Like you also keep a very close eye on my battery and very seldom drain it bellow 35% SOC 

Here is my dashboard of the last six months.

[mzezman]

Your initial post + Snypers on MyBB is what spurred me into action... so thank you!!

Do you forsee any upgrades or is what you have fine for the forseeable future

[zsde]

Great feedback on your experience.
Also took the plunge 14 months ago. My prime motivation was independence from the unreliable supply. And of course, secondary,  the potential long term savings per kWh.
My initial ROI was just on ten years based on a years average usage before solar. And as one uses the system one tends to also try and use the wasted solar in the day, i.e. make use of conveniences that one didn't make use of before.
Thus with the current usage pattern my ROI is already down to around 7 years, ignoring any further prices increases.
What I would like, but can't justify financially, is more storage. The few times that I tap into the grid to ensure my battery bottoms out at 30% or higher overnight ends up costing me 10 to 20kWh grid per month. 
At the current tariff of R2 per kWh where we are, I budget R50 a month. That would be R600 per year or R6 000 over ten years. A second battery would be 25 to R30k and with an expected 10 year lifespan it just doesn't make economic sense to have the bragging rights of enough storage.
The system does what I initially set out to satisfy and was the best decision ever. The independence is what matters more than anything else.
If I were to add something now it would be a second inverter like @Antonio de Sahas. Not because I often need more than 5kW, but rather as redundancy if and when an inverter decides to break down.

[Antonio de Sa]

1 hour ago, zsde said:

Great feedback on your experience.
Also took the plunge 14 months ago. My prime motivation was independence from the unreliable supply. And of course, secondary,  the potential long term savings per kWh.
My initial ROI was just on ten years based on a years average usage before solar. And as one uses the system one tends to also try and use the wasted solar in the day, i.e. make use of conveniences that one didn't make use of before.
Thus with the current usage pattern my ROI is already down to around 7 years, ignoring any further prices increases.
What I would like, but can't justify financially, is more storage. The few times that I tap into the grid to ensure my battery bottoms out at 30% or higher overnight ends up costing me 10 to 20kWh grid per month. 
At the current tariff of R2 per kWh where we are, I budget R50 a month. That would be R600 per year or R6 000 over ten years. A second battery would be 25 to R30k and with an expected 10 year lifespan it just doesn't make economic sense to have the bragging rights of enough storage.
The system does what I initially set out to satisfy and was the best decision ever. The independence is what matters more than anything else.
If I were to add something now it would be a second inverter like @Antonio de Sahas. Not because I often need more than 5kW, but rather as redundancy if and when an inverter decides to break down.

@zsde Yes indeed, having two gives me so kind of redundancy in case one fails, based on my house maximum consumption of about 4 Kw, my reasoning when deciding in installing two was the fact that non of them will be pushing more that 2 Kw. Hence running my inverters @ maximum of   +_ 50%

 

[Bobster.]

The easiest saving to calculate is the saving on the meter. I initially figured about a 7 year payback. I now think about 11. But that's on the meter. In the meantime we sail through loadshedding, and there are other soft benefits. Our fridges always stay on, the contents of the deep freeze are safe. 

Just having the lights and telly on during load shedding is a big improvement. We donated a very new inverter & batteries to my mother. Then I put in some of those led lamps with a little battery in them. Now when the power is off, she can watch some telly, do her knitting, see where she's going, read in bed. This is a step back towards regular life, and it has some value. 

So there are soft values as well. These all add to the benefit that we derive from our systems. 

[Scubadude]

I'm close to the one year mark and will do a short write up when I get there. My system is a little smaller, and a family of 6 is energy intensive (and reluctant to make changes) so payback may be longer than expected . My biggest learning is that you can net get system design "just right" and even detailed planning are indicators at best. To illustrate this point ... I started in summer and proudly stated I needed a third battery to maximise output. Come winter I was caught panel-light due to shading and low rake angle. Second biggest learning, to set alongside it, is that the ROI does not matter - not having to cramp your lifestyle does. We sailed through 2.2GWh of September loadshedding without as much as a power dip.

Edited October 23, 2022 by Scubadude

[Peter V]

I wonder how many of you started out doing it for primarily for ROI only to find down the track the calculation was perhaps somewhat optomistic? I think we all do it for convenience anyway.

Personally, I started with a 5kVA, 5 kW battery system in August 2020 and upgraded to 4,32 kWp of panels and a 10kW battery in February this year. Panels alone assuming a write off on past investment did not really make sense considering my age (almost 70) and the battery upgrade, even less so. What I have is a happy wife and a saving of R1000 to R1300 per month in living expense.

[Johandup]

50 minutes ago, Peter V said:

I wonder how many of you started out doing it for primarily for ROI only to find down the track the calculation was perhaps somewhat optomistic? I think we all do it for convenience anyway.

Personally, I started with a 5kVA, 5 kW battery system in August 2020 and upgraded to 4,32 kWp of panels and a 10kW battery in February this year. Panels alone assuming a write off on past investment did not really make sense considering my age (almost 70) and the battery upgrade, even less so. What I have is a happy wife and a saving of R1000 to R1300 per month in living expense.

So true as it is the same for me.

As I get older I get a lot more intolerable for guvament errors.

The convenience of having solar power and borehole water means a lot to me.

Saving for me is in the same ballpark.

[Sc00bs]

Thanks for the break down on your ROI @RichardZA

The way I see it however is that I highly doubt that we will ever have a reliable Eskom again in South Africa. 

I doubt very much that the ANC is going to be able to sort it out and think that it is just going to get worse. It is up to each individual to decide if they can live with power being switched of for 2-6hrs a day and if not how they are going to make a plan as to how they are going to cope with it.

The way I see it, the only option with some sort of ROI is a solar system.

 

[Antonio de Sa]

23 minutes ago, Johandup said:

So true as it is the same for me.

As I get older I get a lot more intolerable for guvament errors.

The convenience of having solar power and borehole water means a lot to me.

Saving for me is in the same ballpark.

A borehole will be my next investment, I'm of the opinion that we will soon have water shedding as well. So far with my small system I've been able to cope with load shedding. 

[Bobster.]

PS: My savings are about R1500 per month - on COJ's current pre-paid tariff.

I use PV to heat water. We have two geysers. The main geyser is heated by a heat pump, and I can run that twice a day off battery and PV (it's on the backed up circuits).

The guest geyser has an element, but I if time it for times of day when I have sufficient PV but not much load, I can heat that in an afternoon.

[Antonio de Sa]

9 minutes ago, Bobster. said:

PS: My savings are about R1500 per month - on COJ's current pre-paid tariff.

I use PV to heat water. We have two geysers. The main geyser is heated by a heat pump, and I can run that twice a day off battery and PV (it's on the backed up circuits).

The guest geyser has an element, but I if time it for times of day when I have sufficient PV but not much load, I can heat that in an afternoon.

@Bobster. My entire house is on essentials, presently wife is using the stove, heating up my 3 Kw geyser and charging the battery at 7 amps, Ok I have to admit sun is shining.

[Bobster.]

22 minutes ago, Antonio de Sa said:

A borehole will be my next investment, I'm of the opinion that we will soon have water shedding as well. So far with my small system I've been able to cope with load shedding. 

I've been thinking about a borehole. Only thinking, because I don't have the folding stuff. and, for reasons of layout, it will hard to get the equipment into our garden. But is that water potable? Does the water in the tank need treatment?

[Bobster.]

1 minute ago, Antonio de Sa said:

@Bobster. My entire house is on essentials, presently wife is using the stove, heating up my 3 Kw geyser and charging the battery at 7 amps, Ok I have to admit sun is shining.

We have gas for cooking. So the stove is backed up, but all that it needs is a little power for the sparkers and the extraction fan in the oven.

[Antonio de Sa]

1 minute ago, Bobster. said:

I've been thinking about a borehole. Only thinking, because I don't have the folding stuff. and, for reasons of layout, it will hard to get the equipment into our garden. But is that water potable? Does the water in the tank need treatment?

I'm sure one will have to have the borehole water tested by a lab. but one can treat according to the lab results and use it, or with some plumbing modification use that water for everything except drinking and cooking.

 

[Johandup]

4 hours ago, Antonio de Sa said:

I'm sure one will have to have the borehole water tested by a lab. but one can treat according to the lab results and use it, or with some plumbing modification use that water for everything except drinking and cooking.

 

Lots on this topic in the forum: Sustainable Landscaping

If you are fortunate (like me) to have good water it is a blessing. I had one access into my yard and thats where the water (20kl hr) was.

There are many ways to clean water to make it potable.

Once Eskom goes the water supply will follow …

 

[CyberJoe]

When I used to drive a Jeep I complained about fuel consumption, and the best advice received was that the only way to improve fuel consumption was to stop logging and analysing it, so I did just that, and have been doing that since with all vehicles, stop, fill up, drive off. I now get fantastic fuel consumption and never worry about it. 

Same for solar, I got caught with my pants down, the area where I live did not have load shedding until about 3 years ago, ran out and bought this light, and that battery, then this battery stops working, that light gave problems etc. I realised that before I wipe the snot out of my eyes I am going to be spending a lot of cash on a lot of small crappy products, and I will still be sitting in the dark during load shedding. 

I had a bit of cash, bought the 5kw inverter, with 5kw hubble and 6 panels. 

It changed my life, what is load shedding again?

I do now however try to optimise absolutely everything I can so see how much I can spare on my electricity bill, so far this time of year it might be about R700pm.

Was this an investment? Absolutely. Investment in my lifestyle and sanity. There is nothing more depressing that walking around with little camp lights in a dark house.

[Peter V]

20 hours ago, Johandup said:

Lots on this topic in the forum: Sustainable Landscaping

If you are fortunate (like me) to have good water it is a blessing. I had one access into my yard and thats where the water (20kl hr) was.

There are many ways to clean water to make it potable.

Once Eskom goes the water supply will follow …

 

I live in a town house but have managed to squeeze in 3900 litre of rain water storage. Not enough for our normal monthly usage but certainly will help when the Buffalo City water department misbehaves which happens from time to time. To crown it they recently put their foot in it and announced that they would be charging for storage. They retracted when someone told them to go and read the water legislation carefully which only applies to tanks with a direct connection into the municipal supply which makes sense.

 

Sorry mods, drifting a bit off topic here.

Edited October 24, 2022 by Peter V

[RichardZA]

On 2022/10/22 at 12:55 PM, mzezman said:

Your initial post + Snypers on MyBB is what spurred me into action... so thank you!!

Do you forsee any upgrades or is what you have fine for the forseeable future

The only thing that nags at my mind is another 4.8kwH battery because load shedding is getting worse and power outages more frequent. Some additional cover would be great - but this is a pure lifestyle purchase because I'm not going to make the money back easily on it!

Other than that, start saving for when the inverter packs up. Hopefully in 10 years, and hopefully the tech is even better and cheaper then

Unlike some other posters, I started out just wanting to reduce my crazy electricity bill. Load shedding was definitely a secondary consideration (I already had a small batter backup for internet, computers etc). Now I've gone 180 degrees - protection from load shedding is definitely the #1 reason for having solar, and then the secondary benefit is getting some of that money back in reduced bills.