Focused Load-Shedding Solution Saves Money

[jpbarnard2019]

So, we all struggle with load-shedding, right? So, we hand out big wads of cash or credit to install a power wall of sorts, right?
Not necessarily.

I have a big issue with the quick-rich brigade, who have crawled from the woodwork and galloped to the so-called rescue of the suffering SA public. In return for at least R60k, these heroes of the rags-to-riches-in-30-days types will provide you with a 5kVA solution. Need 7.5 kVA, boy, you must add another R20k to R30k. But do you really need a plug to plug solution, when you only really need power backup on certain power outlets in your home. I am in that situation, and I bet, so are many other South Africans. What I need is a focused solution.

I live alone in a flat with three bedrooms (one is actually my home office). So, I thought: Where are my real pain points? In other words, at what wall outlets do I really need power backup during up to 4h of load-shedding misery? Well, in my case, three, actually:

a) My fibre ONT & WIFI router stack plus my lounge table lamp (fed from a single wall outlet in my lounge)
b) My home office stack, fed from a single wall outlet in my third bedroom-turned-home office
c) My smart TV and HiFi stack (fed from another single wall outlet in my lounge)

For the rest I do not really need power backup. The geyser and stove are excluded anyway from most power walls in the 5kVA - 7.5kVA range. I have a small gas stove for making tea and cooking breakfast. My fridge keeps cool enough through 4h of load shedding. I do not need power backup on any of the other wall outlets or light circuits. But, you say, you can install a power wall for only some circuits. Yes, but too many unnecessary outlets are included in each circuit. So, you end up paying for a solution of which you only really need, and use, 50%. There is a better, more focused solution: Power stations.

I have purchased and deployed three power stations, each of approximately the right size, to each of the above pain points in my flat:
a) A 260 Wh 300 W EcoFlow River 2 at the Internet stack
b) A 512 Wh 500W EcoFlow River 2 Max in my home office
c) A 716 Wh 1000W Bluetti EB70 for my TV-HiFi stack

At a total capital expenditure of about R30k, I have addressed the top three pain points in my flat, as opposed of forking out at least R60k for a 5kVA central power wall. All three power stations use LiFePO4 batteries with at least 2500 full recharge cycles (0-100%).

There are some caveats. It turns out that the River 2 Max is electrically too noisy to drive the HiFi stack. While it is recharging, the transformer causes 50Hz hum on the speakers. So, I opted for the Bluetti, which separates its power supply from the main power station unit and uses pass-through, not pass-by circuitry. Less efficient, but more suitable to power a HiFi. There may be other noise suppression options for the River 2 Max, such as ferrite suppressors, but I do not want to experiment when handing out R12k for a power station (as in the case of the River 2 Max). Also, the transfer time from battery to mains on the River 2 Max causes my sound amp to switch off each time. Not optimal while watching a movie of listening to music. The external Bluetti power supply is a bit noisy (fan noise), but I can decide to switch it off while watching TV or listening to music.

And there you have it. Perhaps not quite as comprehensive and slick as a central power wall, but I have saved at least R30k with this solution and addressed the most important pain points in my flat when it comes to load-shedding.

 

[soulie]

So, we all struggle with load-shedding, right? So, we hand out big wads of cash or credit to install a power wall of sorts, right?
Not necessarily.

I have a big issue with the quick-rich brigade, who have crawled from the woodwork and galloped to the so-called rescue of the suffering SA public. In return for at least R60k, these heroes of the rags-to-riches-in-30-days types will provide you with a 5kVA solution. Need 7.5 kVA, boy, you must add another R20k to R30k. But do you really need a plug to plug solution, when you only really need power backup on certain power outlets in your home. I am in that situation, and I bet, so are many other South Africans. What I need is a focused solution.

I live alone in a flat with three bedrooms (one is actually my home office). So, I thought: Where are my real pain points? In other words, at what wall outlets do I really need power backup during up to 4h of load-shedding misery? Well, in my case, three, actually:

a) My fibre ONT & WIFI router stack plus my lounge table lamp (fed from a single wall outlet in my lounge)
b) My home office stack, fed from a single wall outlet in my third bedroom-turned-home office
c) My smart TV and HiFi stack (fed from another single wall outlet in my lounge)

For the rest I do not really need power backup. The geyser and stove are excluded anyway from most power walls in the 5kVA - 7.5kVA range. I have a small gas stove for making tea and cooking breakfast. My fridge keeps cool enough through 4h of load shedding. I do not need power backup on any of the other wall outlets or light circuits. But, you say, you can install a power wall for only some circuits. Yes, but too many unnecessary outlets are included in each circuit. So, you end up paying for a solution of which you only really need, and use, 50%. There is a better, more focused solution: Power stations.

I have purchased and deployed three power stations, each of approximately the right size, to each of the above pain points in my flat:
a) A 260 Wh 300 W EcoFlow River 2 at the Internet stack
b) A 512 Wh 500W EcoFlow River 2 Max in my home office
c) A 716 Wh 1000W Bluetti EB70 for my TV-HiFi stack

At a total capital expenditure of about R30k, I have addressed the top three pain points in my flat, as opposed of forking out at least R60k for a 5kVA central power wall. All three power stations use LiFePO4 batteries with at least 2500 full recharge cycles (0-100%).

There are some caveats. It turns out that the River 2 Max is electrically too noisy to drive the HiFi stack. While it is recharging, the transformer causes 50Hz hum on the speakers. So, I opted for the Bluetti, which separates its power supply from the main power station unit and uses pass-through, not pass-by circuitry. Less efficient, but more suitable to power a HiFi. There may be other noise suppression options for the River 2 Max, such as ferrite suppressors, but I do not want to experiment when handing out R12k for a power station (as in the case of the River 2 Max). Also, the transfer time from battery to mains on the River 2 Max causes my sound amp to switch off each time. Not optimal while watching a movie of listening to music. The external Bluetti power supply is a bit noisy (fan noise), but I can decide to switch it off while watching TV or listening to music.

And there you have it. Perhaps not quite as comprehensive and slick as a central power wall, but I have saved at least R30k with this solution and addressed the most important pain points in my flat when it comes to load-shedding.

hope you didnt type all that on a phone .

 

[leon.davibe]

30k for 1.5kwh

While a 3 000 watt pure sine wave inverter and 2.5kwh battery power could be had for about 20k

Now you would have enough spare capacity , to heat up a meal in the micro, have a cup of coffee while watching a movie

As long as the power stations are LFP it is ok to each his own

If not LFP smaller battery will see you use. About a cycle a day and and 3 years down the line the li-ion batteries will lose 20% capacity if you need full capacity to pull through a shedding now you can't , if doing more than one shedding a day time shrinks

 

[Tomtomtom]

Definitely people are overkilling this thing. Especially when they decide they need a full solar setup covering everything but the oven.

In many cases I think people don't realise how much difference a small system can make if it's set up strategically. Like the only options for getting to the shops are a) walking or b) a Bugatti.

We spent R 14k on a single 1 kW / 1.2 kWh portable inverter UPS and a few extension cables.

It covers:

1. Router / WiFi etc. (~ 30 W)
2. Home office (~150 W)
3. TV / sound (~ 100 W)
4. House ceiling lights ( ~ 100 W) (+ R 2k installation)

I can't recommend #4 with a portable system but it makes a HUGE difference. We can brag that we don't notice loadshedding almost as often as can people who have dropped ten times as much.

Makes you realise why lights were the first thing anyone installed when electricity was first introduced 100+ years ago.

 

[Forum Reader]

Here's what I did:

- Got a powerbank for free from work which I use to power my router
- nothing else

Laptop lasts at least two hours and phone lasts even longer. Also have a spare powerbank to charge phone further that I bought to boost my car battery back when it was going flat during covid.

If I need a bit of light for a while at night I switch on my USB selfie light which plugs into the laptop. Super bright.

 

[Neuk_]

Definitely people are overkilling this thing. Especially when they decide they need a full solar setup covering everything but the oven.

In many cases I think people don't realise how much difference a small system can make if it's set up strategically. Like the only options for getting to the shops are a) walking or b) a Bugatti.

We spent R 14k on a single 1 kW / 1.2 kWh portable inverter UPS and a few extension cables.

It covers:

1. Router / WiFi etc. (~ 30 W)
2. Home office (~150 W)
3. TV / sound (~ 100 W)
4. House ceiling lights ( ~ 100 W) (+ R 2k installation)

I can't recommend #4 with a portable system but it makes a HUGE difference. We can brag that we don't notice loadshedding almost as often as can people who have dropped ten times as much.

Makes you realise why lights were the first thing anyone installed when electricity was first introduced 100+ years ago.

I think you'll find that most that go with a full ESS are thinking further than a few 2 hour load shedding slots.

 

[Tomtomtom]

I think you'll find that most that go with a full ESS are thinking further than a few 2 hour load shedding slots.

That's what everyone who has spent R 100k+ must say in order to validate their decision.

To be clear if I were not renting I would be on the solar train myself because like every nerd on this forum I positively welcome to opportunity to fiddle around with inverter settings and schedules and I like annoying my wife.

Most people get tired of that crap though and there's a good chance in 5-10 years houses will be littered with dead dust-bunny-filled inverters the way gardens in Cape Town are littered with mosquito-infested JoJo tanks.

 

[leon.davibe]

That's what everyone who has spent R 100k+ must say in order to validate their decision.

To be clear if I were not renting I would be on the solar train myself because like every nerd on this forum I positively welcome to opportunity to fiddle around with inverter settings and schedules and I like annoying my wife.

Most people get tired of that crap though and there's a good chance in 5-10 years houses will be littered with dead dust-bunny-filled inverters the way gardens in Cape Town are littered with mosquito-infested JoJo tanks.

I do think the solar backup system is a bit different than the jojo

The jojo replaces a service that cost you what per month?

The solar on the other hand
Has an up side , electricity is expensive

Spending a bit extra on panels has an upside savings that won't just earn its cost back but the inverter qnd batteries cost too

Are some overdoing yea maybe

But then again having a setup you can actually cook with, saves how much on takeaways

What is the premium on takeaways vs cooking

Over x years?

 

[Tomtomtom]

The jojo replaces a service that cost you what per month?

Ironically on pure storage a JoJo wins. A 10 kL tank costing ~R 17k holds ~R 200 worth of water. The equivalent cost in LFP battery stores about R 10 worth of electricty.

Obviously that's where the comparison ends but nevertheless nobody argues that full-blown solar systems make sense either unless you value your loadshedding-proof life at a few grand a month or whatever.

The interesting question is what is that marginal cost/benefit? Having dropped R 17k on a setup that gets us 80% of the way, the cost to do a whole house system is still ~R 80k away.

For R 80k, all we'd get in addition to what we already have is the ability to run the microwave and the dishwasher whenever we want. It seems like ridiculously poor value.

I think this is why people get dragged by the sunk cost fallacy into dropping another R 30k+ on panels -- it promises some sort of ROI on the investment.

Thing is there's nothing stopping people with small systems like mine running a couple of panels to make it "pay for itself"... but it doesn't ever seem so pressing, probably because we haven't made such huge capital outlays with their attendant opportunity costs.

 

[dolf89]

Could be wrong, but I think you could have done much better for 30k than three power stations (but I am far from an expert, so grain of salt)

For R16K I got a lifepo4 2.56kwh battery and 1000W inverter

Ran cabtyre to each room with a light and a plug for the essentials.

For 30k you could get a 3000V inverter, two lifepo4 batteries for a total of 5.12kwh and have money left to put towards running surface mounted cabtyre, plugs and lights

 

[Harmonic]

That's what everyone who has spent R 100k+ must say in order to validate their decision.

Not really. I've been fortunate enough to uninstall the ESP app and don't really give two thoughts about load shedding anymore. R 100k+ well spent in my opinion.

 

[Tomtomtom]

Not really. I've been fortunate enough to uninstall the ESP app and don't really give two thoughts about load shedding anymore. R 100k+ well spent in my opinion.

Well, one thought still to defend your investment.

As I mentioned we are unaffected 80% of the time, except in our case the total outlay was R 15k + R2k of an electrician's time.

The additional R 80k+ it would cost to not have to delay the dishwasher some days makes no sense, especially for a renter.

The big win imo is just having lights on a UPS, and lights are only ~100 W.

Of course if you spent R 100k or R 1 MM or whatever you regret nothing. You're getting to the shops in a Bugatti. But if you've overlooked all the other options between walking and the supercar, and had other useful things you could have done with the money -- then you might have made a mistake.

But if you're happy, who cares?

 

[leon.davibe]

Ironically on pure storage a JoJo wins. A 10 kL tank costing ~R 17k holds ~R 200 worth of water. The equivalent cost in LFP battery stores about R 10 worth of electricty.

Obviously that's where the comparison ends but nevertheless nobody argues that full-blown solar systems make sense either unless you value your loadshedding-proof life at a few grand a month or whatever.

The interesting question is what is that marginal cost/benefit? Having dropped R 17k on a setup that gets us 80% of the way, the cost to do a whole house system is still ~R 80k away.

For R 80k, all we'd get in addition to what we already have is the ability to run the microwave and the dishwasher whenever we want. It seems like ridiculously poor value.

I think this is why people get dragged by the sunk cost fallacy into dropping another R 30k+ on panels -- it promises some sort of ROI on the investment.

Thing is there's nothing stopping people with small systems like mine running a couple of panels to make it "pay for itself"... but it doesn't ever seem so pressing, probably because we haven't made such huge capital outlays with their attendant opportunity costs.

With the way the electricity prices are increasing going solar becomes a better prospect by each passing year

each home/home office has their own requirements

for some the 1kw won't cut it

ie we have a home office pc's +laser etc see us pull 1.3kw if all the pc's are running

so already to pull through a 4hrs we need the 5kwh+ battery at least

if already having to layout for that size battery , to some it might seem like sunk cost syndrome

if already in with the cost of inverter and battery spending some more money on panels
actually makes good economic sense


Now yes i am nowhere near 100k

Options

Be out of pocket of 40-60k

or layout another R40k and after 7 years be out of pocket for the grand total of R0

and be self sufficient electricity wise

those that have the cash to go that route it's a no brainer, i didn't have the cash ,started small been expanding over the last 3years

only started adding (4) panels recently (one month now with panels R500 savings on electricity)

 

[AchmatK]

That's what everyone who has spent R 100k+ must say in order to validate their decision.

To be clear if I were not renting I would be on the solar train myself because like every nerd on this forum I positively welcome to opportunity to fiddle around with inverter settings and schedules and I like annoying my wife.

Most people get tired of that crap though and there's a good chance in 5-10 years houses will be littered with dead dust-bunny-filled inverters the way gardens in Cape Town are littered with mosquito-infested JoJo tanks.

There's no reason to conjure up anything to validate spending R100k+ when the stats speaks for themselves.

How much do you think 41 000kWh costs from the municipality or eskom.

This is 3 years on with zero maintenance costs and the system is not even breaking a sweat.

It's not just about a load shedding solution but sourcing electricity at a cheaper price than what eskom can provide.

The same for my JoJo and well that's been running since 2018 supplying all our water needs including drinking. I've extracted over 2 000kl saving me over R130k in municipal water bills.

41MWh is over R100k not going to coct at an average price of R2.50/kWh.

 

[Neuk_]

That's what everyone who has spent R 100k+ must say in order to validate their decision.

And yet, here we are in a thread where the OP is justifying not spending R100k+

 

[pinball wizard]

7.5Kw generator is R10k. Losers.

 

[3WA]

7.5Kw generator is R10k. Losers.

Buying a book and a torch is R400.

 

[Harmonic]

7.5Kw generator is R10k. Losers.

And 3l of petrol per day will set you back R25k a year, destroy your ears and damage your dignity. Idiot.

 

[Lupus]

Ironically on pure storage a JoJo wins. A 10 kL tank costing ~R 17k holds ~R 200 worth of water. The equivalent cost in LFP battery stores about R 10 worth of electricty.

Obviously that's where the comparison ends but nevertheless nobody argues that full-blown solar systems make sense either unless you value your loadshedding-proof life at a few grand a month or whatever.

The interesting question is what is that marginal cost/benefit? Having dropped R 17k on a setup that gets us 80% of the way, the cost to do a whole house system is still ~R 80k away.

For R 80k, all we'd get in addition to what we already have is the ability to run the microwave and the dishwasher whenever we want. It seems like ridiculously poor value.

I think this is why people get dragged by the sunk cost fallacy into dropping another R 30k+ on panels -- it promises some sort of ROI on the investment.

Thing is there's nothing stopping people with small systems like mine running a couple of panels to make it "pay for itself"... but it doesn't ever seem so pressing, probably because we haven't made such huge capital outlays with their attendant opportunity costs.

Yeah until the 2 hour shed becomes 12 to 50 hours due to faults on the local substation, then the panels are a god send.

 

[Lupus]

And 3l of petrol per day will set you back R25k a year, destroy your ears and damage your dignity. Idiot.

3l a day? Most of the bigger generators would be 1 to 3l per hour, so if you're at stage 6 it would be quite a bit more.