Extra panels or Solar Geyser?

[wingnut771]

Okay thanks, but I'm still confused about what the waste in this case is, since the grid credit is worth exactly the same as PV power surely?

So if the batteries were to be run down to 40% by morning, then excess PV would charge them, rather than running the meter backwards.

But how is one better than the other?

You can't run the meter backwards during LS but you can charge the battery.

 

[Tomtomtom]

You can't run the meter backwards during LS but you can charge the battery.

Interesting, I see, there is potential waste contingent on daytime/morning loadshedding. @Mike Hoxbig is this what you were referring to?

 

[wingnut771]

Interesting, I see, there is potential waste contingent on daytime/morning loadshedding. @Mike Hoxbig is this what you were referring to?

He's not maximising his PV production, so there is plenty room for improvement with some reconfigurations like moving geysers to essential and using more battery so solar production has something to do during blackouts.

 

[Mike Hoxbig]

Interesting, I see, there is potential waste contingent on daytime/morning loadshedding. @Mike Hoxbig is this what you were referring to?

What @wingnut771 said...

 

[Tomtomtom]

Ok cool, so there is a tradeoff, you want batteries at high enough SoC for loadshedding standby, but not so high that PV goes to waste during daytime loadshedding.

But for OP looking at that chart again the ~17 kWh overnight consumption is mad. The ~6 kWh PV energy missed out on would only close a third of that gap.

Contrary to previous posters I'm not so sure an inverter model would help. Aircon looks to be running nearly flat out. But at 0% and 100% duty cycle there is no difference inverter vs. traditional.

I would maybe try to convince the wife to raise the AC temperature a little above 16 degrees, and take the blankets off. And close the windows.

 

[6174]

Inverters can be configured to use power from their sources in whatever order. The typical one would be:
1) solar
2) grid
3) batteries.
So if there's not enough sun for your needs, they blend in some power from the grid. Batteries are only used during load-shedding.

Again one can skin the proverbial cat in many ways. I personally would have done things differently. I would have gotten a commercial analog of the industrial systems we work on and just use that to control everything without the need to split the DB or anything like that. It is actually a lot easier and it can give you live feedback as most inverters do. Just with a lot more control.

I will maintain my position on the geyser. If you don't have an active intelligent system that can prevent battery use I personally will not go for it. I know most hybrid inverters can mix and switch between modes but continuous power failure is a reality.

This means it might not have grid power to help it out. This can happen on overcast days. An example would be today when we had no power from 11:00 AM till just after 5:00 PM. It is also heavily overcast. This is but one real-world example. We must be able to account for days like this and use the battery capacity wisely.

All I am saying is, I will plan my system a lot differently and introduce dedicated solutions for heating water as but one example. Gas or solar vacuum tubes can help with this. It is not wrong to plan for prolonged power outs. It is why most hybrid systems can accept power from a generator.

The truth is "sh_t happens". I am not trying to be difficult, I am telling you the tech exists to really take solar to the next level and that is what I am planning for myself. I am talking about taking complete control over every aspect of your home so that the battery doesn't get hammered. Batteries are expensive and protecting that investment I feel is well worth the effort.

 

[newby_investor]

I will maintain my position on the geyser. If you don't have an active intelligent system that can prevent battery use I personally will not go for it. I know most hybrid inverters can mix and switch between modes but continuous power failure is a reality.

I'm not sure what part of "the geyser is not connected to the inverter" you aren't registering here.

The geyser only gets to use solar power if there is grid, and the inverter can push back to the grid.

No grid, no geyser. So the batteries aren't compromised at all.

It's all good and well to talk about industrial-scale stuff but it's very expensive and not designed for domestic use. Similarly, I work with 100G, 200G and 400G datacentre networking equipment at work. I don't bring any of it home, I just have a R1000 Asus wifi router.

 

[SauRoNZA]

I am sorry you failed basic English. Factually investing means I placed down a deposit and am committed. But due to my working hours being cut, it will take longer.

You should go back to your school and ask for your money back. They didn't do a good job.

Did you mean actually?

Because I think you are the one who missed out on some basic English lessons because literally in the history of the world nobody has even done factual investing.

 

[Speedster]

Did you mean actually?

Because I think you are the one who missed out on some basic English lessons because literally in the history of the world nobody has even done factual investing.

I've learnt there comes a time when any further discussion with the newbies becomes futile. It was the same with that Leon guy, but at least he seems to have calmed down

 

[SauRoNZA]

Again one can skin the proverbial cat in many ways. I personally would have done things differently. I would have gotten a commercial analog of the industrial systems we work on and just use that to control everything without the need to split the DB or anything like that. It is actually a lot easier and it can give you live feedback as most inverters do. Just with a lot more control.

I will maintain my position on the geyser. If you don't have an active intelligent system that can prevent battery use I personally will not go for it. I know most hybrid inverters can mix and switch between modes but continuous power failure is a reality.

This means it might not have grid power to help it out. This can happen on overcast days. An example would be today when we had no power from 11:00 AM till just after 5:00 PM. It is also heavily overcast. This is but one real-world example. We must be able to account for days like this and use the battery capacity wisely.

All I am saying is, I will plan my system a lot differently and introduce dedicated solutions for heating water as but one example. Gas or solar vacuum tubes can help with this. It is not wrong to plan for prolonged power outs. It is why most hybrid systems can accept power from a generator.

The truth is "sh_t happens". I am not trying to be difficult, I am telling you the tech exists to really take solar to the next level and that is what I am planning for myself. I am talking about taking complete control over every aspect of your home so that the battery doesn't get hammered. Batteries are expensive and protecting that investment I feel is well worth the effort.

Why are you so hell bent on avoiding the use of batteries?

Even when you do have to use them it’s a trickle.

You’ll find most people here with solar run smart homes that directly talk to their inverters.

Quite the contrary you are being very difficult for no logical reason at all telling people already using the tech all about this magical next level we are all already on and you are failing to grasp and catch up to.

 

[6174]

Trash will talk trash all day I get that. If you get this far let me explain a few things here.

One: Most solar systems will not be able to supply an Oven or geyser with power for very long if at all.
Two: Most solar systems will not be able to isolate the geyser when both the solar panels and grid power fails.
Three: a 12Kw battery without grid or solar will be depleted in a few hours. Geyser consumes about ± 3.2Kwh.
Four: Hybrid solar systems can't handle an infinite number of solar panels. There are limits.
Five: Hybrid solar systems can't handle an infinite number of batteries it has limited charge capacity.

In summary, don't let the snake oil fool you, Being off the grid is possible but these systems will call for massive financial investments and you may not get your money's worth with inflated prices and product variation.

In conclusion. Don't trust the information you see here, yes they are owners of solar systems but that does not make them experts, and many of them will not admit if they made a mistake or not. There are some here that are trying to be honest and open about solar but the trolls make it very hard to find out the truth.

 

[SauRoNZA]

Trash will talk trash all day I get that. If you get this far let me explain a few things here.

One: Most solar systems will not be able to supply an Oven or geyser with power for very long if at all.

Strange then how my house and so many others here have EVERYTHING on their hybrid solar inverter and sun electric stoves and ovens every day without any issues whatsoever…

Two: Most solar systems will not be able to isolate the geyser when both the solar panels and grid power fails.

Truly bizarre that mine turns itself on once there is enough solar power and turns itself off when the sun goes goes.

Even more strange how it magically turns off during load shedding and back on…only when the sun is shining.

Three: a 12Kw battery without grid or solar will be depleted in a few hours. Geyser consumes about ± 3.2Kwh.

Half true. The geyser is never stone cold and therefore doesn’t need 12kW and 4 hours to warm itself up.

Four: Hybrid solar systems can't handle an infinite number of solar panels. There are limits.

Of course not. Everything has limits.

None of these limits are unreasonable for residential use.

Also paralleling exists.

Five: Hybrid solar systems can't handle an infinite number of batteries it has limited charge capacity.

And who exactly would need an infinite number of batteries?

Your arguments simply aren’t logical.

In summary, don't let the snake oil fool you, Being off the grid is possible but these systems will call for massive financial investments and you may not get your money's worth with inflated prices and product variation.

In conclusion. Don't trust the information you see here, yes they are owners of solar systems but that does not make them experts, and many of them will not admit if they made a mistake or not. There are some here that are trying to be honest and open about solar but the trolls make it very hard to find out the truth.

In summary you have no idea what you are talking about and speak for little to no experience, while there are a great many very learned people on here who know infinitely more than you do.

You will not find a more knowledgeable collective of people that are as willing to help than you find here.

Six : The batteries in a solar hybrid setup act as a buffer, there is no logical reason to actively avoid using them like you are wanting to do.

So what if your geyser uses 2-5 kWh of batteries on a bad day? It’s the 99% of the time when it’s running on solar that matters and that 1% is still money you didn’t have to pay Eskom.

They serve a purpose and if you don’t want to use them for that purpose…well then I don’t know what to tell you.

Further more there was no reason to make your post in bold, if anything it will have the opposite effect of what you desired and now even less people will read your drivel.

 

[SauRoNZA]

Ok cool, so there is a tradeoff, you want batteries at high enough SoC for loadshedding standby, but not so high that PV goes to waste during daytime loadshedding.

But for OP looking at that chart again the ~17 kWh overnight consumption is mad. The ~6 kWh PV energy missed out on would only close a third of that gap.

Contrary to previous posters I'm not so sure an inverter model would help. Aircon looks to be running nearly flat out. But at 0% and 100% duty cycle there is no difference inverter vs. traditional.

I would maybe try to convince the wife to raise the AC temperature a little above 16 degrees, and take the blankets off. And close the windows.

I think many people have a fundamental misunderstanding of how aircons work, especially non-inverter units thinking that the lower they set them the quicker they’ll cool the place down.

Meanwhile they are always pumping the same temperature of air out and if you leave it at 16 it just burns the compressor all day long costing a fortune while turning the house into a fridge.

24-degrees is quite lekker if you put it on first thing in the morning and just let it go it’s thing all day and it’s what most units do on their Auto modes. Heater on below 18, cooler on above 24.

Inverters on the other hand actually push air out at the temperature set and again this may not seem super cool at first but just set and forget and call it a day.

Sure if you are one of those types set it to 22 but there is really no reason for less.

 

[SauRoNZA]

We use the electric oven on sunny days because it's free, unlike gas.

On sunny days we use the tumble drier because it's free.

Why would you think people who have solar systems wouldn't know this stuff?

Of course we can also use them on battery, but I just use the gas oven and hob after dark. We do our tumble drying, laundry etc during the day. We only really run the dishwasher and aircon after dark.
The aircon sometimes runs all night on battery. If I anticipate an extended outage or bad weather, I top up the battery with Eskom.

This is no silver bullet, but I have not been offline in a year now. My neighbours have been off for 36 hours + a number of times. We have 25kl water on prem. They have no water while Eskom is down for extended outages. I have satellite internet backup. Nobody can even send a WhatsApp around me during extended outages. I'm not bragging, just saying you'd have a hard time telling me the spend wasn't worth it.

I'm not sure what you mean by 12kw battery and 3kwh geyser. I have a 10kwh battery and my geyser is 3kw... If I really was in a bind and had to run my geyser on battery, I could do it for an hour and still have 2/3 battery capacity, but I have never needed to use it for the geyser. If the weather was really bad for a week and Eskom was off, I'd just use the gas stove and avoid electric heating or aircon...

How dare you?

Didn’t you know it’s almost impossible to run an oven and a geyser on a solar setup?

How on earth could you run the tumble dryer too? Madness.

Devil worship I tell you!

****

Seriously though why run dishwasher after dark? I set mine the night before to run at 10:00 the next morning and that works out pretty well.

 

[6174]

We use the electric oven on sunny days because it's free, unlike gas.

On sunny days we use the tumble drier because it's free.

Why would you think people who have solar systems wouldn't know this stuff?

Of course we can also use them on battery, but I just use the gas oven and hob after dark. We do our tumble drying, laundry etc during the day. We only really run the dishwasher and aircon after dark.
The aircon sometimes runs all night on battery. If I anticipate an extended outage or bad weather, I top up the battery with Eskom.

This is no silver bullet, but I have not been offline in a year now. My neighbours have been off for 36 hours + a number of times. We have 25kl water on prem. They have no water while Eskom is down for extended outages. I have satellite internet backup. Nobody can even send a WhatsApp around me during extended outages. I'm not bragging, just saying you'd have a hard time telling me the spend wasn't worth it.

I'm not sure what you mean by 12kw battery and 3kwh geyser. I have a 10kwh battery and my geyser is 3kw... If I really was in a bind and had to run my geyser on battery, I could do it for an hour and still have 2/3 battery capacity, but I have never needed to use it for the geyser. If the weather was really bad for a week and Eskom was off, I'd just use the gas stove and avoid electric heating or aircon...

How much did you pay for your solar system? How many years will it take to repay itself? sorry to break it to you but using your electric stove on a sunny day isn't free. You still paid for it. Well, basically you could have gotten about ± 75471 units of power depending on how much you paid, what the interest will be, and what you will pay on maintenance and insurance. yea... I didn't have to take out an R200k Loan to cook my food. I just grab myself about R300 worth of gas and it last for about a month sometimes a bit longer depending on how much coffee I consume.

 

[droidx]

How much did you pay for your solar system? How many years will it take to repay itself? sorry to break it to you but using your electric stove on a sunny day isn't free. You still paid for it. Well, basically you could have gotten about ± 75471 units of power depending on how much you paid, what the interest will be, and what you will pay on maintenance and insurance. yea... I didn't have to take out an R200k Loan to cook my food. I just grab myself about R300 worth of gas and it last for about a month sometimes a bit longer depending on how much coffee I consume.

So he could have bought units to last him roughly the next 10 years at current pricing? With the rate of increases that could be a smart choice.
The only issue is the uptime of our utility provider which isn’t very promising right now.
Ok, so stock up on some back up solutions and cooking alternatives, wood, coals gas.
Now there’s that pesky lengthy outages to worry about.
Now he has to get some more back up, to cover items like food storage so that it doesn’t go off.
He also has to hope that there is enough uptime for his 10 years worth of units to actually be used.


If only there were a way to lock in current pricing and have better availability of electricity to do more than cooking, which I’m sure he’ll use a R300 gas canister for anyway. Do you have any suggestions?

 

[wingnut771]

Ok cool, so there is a tradeoff, you want batteries at high enough SoC for loadshedding standby, but not so high that PV goes to waste during daytime loadshedding.

But for OP looking at that chart again the ~17 kWh overnight consumption is mad. The ~6 kWh PV energy missed out on would only close a third of that gap.

Contrary to previous posters I'm not so sure an inverter model would help. Aircon looks to be running nearly flat out. But at 0% and 100% duty cycle there is no difference inverter vs. traditional.

I would maybe try to convince the wife to raise the AC temperature a little above 16 degrees, and take the blankets off. And close the windows.

I still want to see the boob graph. The only one posted must have been cloudy or else he has shadows all over his roof.

 

[wingnut771]

I think many people have a fundamental misunderstanding of how aircons work, especially non-inverter units thinking that the lower they set them the quicker they’ll cool the place down.

Meanwhile they are always pumping the same temperature of air out and if you leave it at 16 it just burns the compressor all day long costing a fortune while turning the house into a fridge.

24-degrees is quite lekker if you put it on first thing in the morning and just let it go it’s thing all day and it’s what most units do on their Auto modes. Heater on below 18, cooler on above 24.

Inverters on the other hand actually push air out at the temperature set and again this may not seem super cool at first but just set and forget and call it a day.

Sure if you are one of those types set it to 22 but there is really no reason for less.

It depends on the relative humidity for me. Living in Durban comfortable setting can be anything between 20 - 24 degrees on the Aircon.

 

[B-1]

How much did you pay for your solar system? How many years will it take to repay itself? sorry to break it to you but using your electric stove on a sunny day isn't free. You still paid for it. Well, basically you could have gotten about ± 75471 units of power depending on how much you paid, what the interest will be, and what you will pay on maintenance and insurance. yea... I didn't have to take out an R200k Loan to cook my food. I just grab myself about R300 worth of gas and it last for about a month sometimes a bit longer depending on how much coffee I consume.

I think you should just give up trying to justify your way as the only way. Claiming a R3600 annual cost that is susceptible to increases and supply issues is better to cook your food because it has a smaller upfront commitment is ridiculous. All the other costs like insurance and maintenance are similar. Solar installs if done correctly are very reliable.

To be honest you just sound like you have no idea what you are talking about.

 

[Pegging]

How much did you pay for your solar system? How many years will it take to repay itself? sorry to break it to you but using your electric stove on a sunny day isn't free. You still paid for it. Well, basically you could have gotten about ± 75471 units of power depending on how much you paid, what the interest will be, and what you will pay on maintenance and insurance. yea... I didn't have to take out an R200k Loan to cook my food. I just grab myself about R300 worth of gas and it last for about a month sometimes a bit longer depending on how much coffee I consume.

Look for the Solar is a f_up thread here somewhere in January. About half the thread is about using homeloans and payback periods for solar.

In sort its 7 to 12 years, payback. It should have a decent resale value and the various parts last from 10 to 40 years.
So something like the panels should pay for themselves many times over if you keep rinsing off the bird poop.