Hello Powerforum,

Another complete noob checking in.

I am hoping for some clarity. I know there's no doubt a ton of reading to do here but frankly I'm a bit burnt out trying to get my head around it all. Hoping for some quick answers as no doubt I'll be back with a million more questions.

Looking to get going on solar. I was hoping to do this in at least two phases - first being a minimum of inverter and battery and then adding panels at a later stage. If this is not the way to go about it please let me know your thoughts.

For an average household of four, here are the basics I'm looking to start with:

 

- Deye 8kW Hybrid Inverter

- SAKO Rechargeable Deep Cycle Lifepo4 Li Ion 10KW Powerwall 48v200ah Lifepo4 Lithium Ion Solar Battery Pack

 

The battery especially I'm flexible on in terms of brand (prices seem to have gone ballistic since I checked a short while ago). Any feedback on that combo greatly appreciated.

 

My questions are:

 

1.) Can panels be added one/two at a time? Or is it better/only possible to install a full MPPT at a time? I have two decent north-facing roof spaces in mind.

2.) What spec panels can I use? I've heard the Deye 5kW can use no larger than 500W? Is this the case with the 8kW? What would be the ones to go for? Canadian Solar? I would like to get the best reasonable option to maximise use of roof space and wattage.

That's all I can think of for now. Feedback appreciated.

 

 

 

Edited April 19, 20233 yr by SunTax

4 hours ago, SunTax said:

Hello Powerforum,

Another complete noob checking in.

I am hoping for some clarity. I know there's no doubt a ton of reading to do here but frankly I'm a bit burnt out trying to get my head around it all. Hoping for some quick answers as no doubt I'll be back with a million more questions.

Looking to get going on solar. I was hoping to do this in at least two phases - first being a minimum of inverter and battery and then adding panels at a later stage. If this is not the way to go about it please let me know your thoughts.

For an average household of four, here are the basics I'm looking to start with:

 

- Deye 8kW Hybrid Inverter

- SAKO Rechargeable Deep Cycle Lifepo4 Li Ion 10KW Powerwall 48v200ah Lifepo4 Lithium Ion Solar Battery Pack

 

The battery especially I'm flexible on in terms of brand (prices seem to have gone ballistic since I checked a short while ago). Any feedback on that combo greatly appreciated.

 

My questions are:

 

1.) Can panels be added one/two at a time? Or is it better/only possible to install a full MPPT at a time? I have two decent north-facing roof spaces in mind.

2.) What spec panels can I use? I've heard the Deye 5kW can use no larger than 500W? Is this the case with the 8kW? What would be the ones to go for? Canadian Solar? I would like to get the best reasonable option to maximise use of roof space and wattage.

That's all I can think of for now. Feedback appreciated.

 

 

 

1. The minimum start is 4 panels that can provide at least 150V to start the MPPT. 

2. No you can use any size panel. One wonders what is the source of information like this. 

This is AFAIK with my limited knowledge of the Deye. 

Yeah you need to watch that MPPT minimum in order for it to start. 

You can use any panel, however you need to watch the voltage and current top ends else you'll blow things 

Hi everyone, newbie here, I am busy putting a solar system together for the house, just want to find out how important putting the solar panels on the north facing side is? If it wont affect the system too badly I would really prefer putting the solar panels on the south facing side, just for security reasons, the north facing side faces the street is in plain sight.

 

Thanks in advance for any advice.

Have a good times 

On 2019/08/06 at 12:42 PM, stoic said:

I'm with you on this one even though i have not tried the EV Tubes, it was just a lot more cost effective to shower in the evenings around 6PM and heat both my geysers again during the day when there is ample PV.

The only change i made was change my elements to 2kw elements to make sure i do not overwork the inverts. these now run from 10am-1pm and the other from 1pm -3pm.

I have an extremely dedicated wife that manages this though. I had it on timers, but she seems to enjoy monitoring and flicking the switches  

 

So I have a question. We seem to have a really old geyser that is using a lot of power. We are installing a solar system with 2X  5kWh inverters 2X 6.14deye batteries and 14 550 panels. I keep seeing suggestions to change element in geyser to 2kw. My question is what will that achieve I assume a smaller element will just take longer to heat a same sized geyser is the changing element supposed to reduce the pressure on the system by pulling less and taking longer? Also what is the most efficient electric geysers out there as spending about 30000 now for a solar one is out of question. 

1 hour ago, Kory said:

So I have a question. We seem to have a really old geyser that is using a lot of power. We are installing a solar system with 2X  5kWh inverters 2X 6.14deye batteries and 14 550 panels. I keep seeing suggestions to change element in geyser to 2kw. My question is what will that achieve I assume a smaller element will just take longer to heat a same sized geyser is the changing element supposed to reduce the pressure on the system by pulling less and taking longer? Also what is the most efficient electric geysers out there as spending about 30000 now for a solar one is out of question. 

I wouldn't make any changes with regard to a solar geyser or anything without understanding your power consumption versus generation with the new system. That is to say, how much of your 14 x 550W panels can generate spare power during the day to divert to warming the geyser? If you've got a Deye inverter, this could be possible to set up, to heat water from solar, but without taking power from the battery.

You're correct, the 2kW element helps to heat water more slowly if you've got a limited amount of spare solar power. But you have a lot of panels and two inverters, such that you might not need to reduce the element size, even if you've got maybe a biggish 4kW element.

The most efficient way to heat water electrically is via a heat pump. However if the solar system you're installing can cover the current geyser then you can leave it as is.

As you say, the benefit of downgrading to a smaller element is that it consumes less power whilst running; which means that even if the geyser takes longer to heat (thus consuming the same total energy), you may find that solar can cover its consumption better at that lower peak, for that longer duration.

In contrast if it, say, consumes 4kw and your system is only able to generate 2kw, the balance would have to come from grid/battery.

Different size geyser elements are typically similar in efficiency; with the difference only being how long they need to heat for.

Get the system installed and then review whether or not you're able to cover the existing unit as-is. If not, downgrading to a smaller element is simple and inexpensive.

15 minutes ago, JayMardern said:

The most efficient way to heat water electrically is via a heat pump. However if the solar system you're installing can cover the current geyser then you can leave it as is.

As you say, the benefit of downgrading to a smaller element is that it consumes less power whilst running; which means that even if the geyser takes longer to heat (thus consuming the same total energy), you may find that solar can cover its consumption better at that lower peak, for that longer duration.

In contrast if it, say, consumes 4kw and your system is only able to generate 2kw, the balance would have to come from grid/battery.

Different size geyser elements are typically similar in efficiency; with the difference only being how long they need to heat for.

Get the system installed and then review whether or not you're able to cover the existing unit as-is. If not, downgrading to a smaller element is simple and inexpensive.

Thanks for this. The final question is we have lived in this house for 8 years and haven’t changed the geyser or worked on it ever. I am not sure if there has been any significant improvements in geyser technology. The previous owner of the house wasn’t one for buying the very best of things, though the house was liveable we have spent quite a bit of time and money doing quality improvements. My question is over the past 8 years has there been any changes or improvement in geyser technology? Would we benefit from a more recent electric geyser in terms of energy efficiency? Yes our system will cover the geyser especially if we use a timer to ensure it heats during the day mainly. Ultimately,  I am opting for oversizing our solar system to cover the geyser rather than buying a solar geyser. So the plan is to in the near future change our two geysers to the most energy efficient ones we can get and use the system to power it. Currently I know we have a 150lt geyser for our 1 bedroom granny flat- I plan to change that to a 100lt as the maximum occupancy for the flat is 2. We have occasional had 3/4 guests but that’s under special circumstances. 

Elements haven't changed much, but modern geysers can be more efficient overall due to superior insulation. Thus newer geysers may lose less heat (ie, they exhibit less standing losses). If you find this is an issue, you could always compensate for this via geyser blankets, for example.

You can test by heating to full temperature, powering the geyser off, not using hot water for as long as possible, and then powering on to see how long the element needed to run for after not being used. (I've experienced up to 3.5kWh of loss per 24 hours in summer, on one of my geysers, by testing this way. I'd imagine a newer geyser - or added insulation - would improve this).

The same applies to the plumbing/piping around the geyser: any heat radiated from there is lost.

I used to run 10 x 455 (4550W) panels and was just barely able to heat both of my geysers (a 150l 3kW; and a 200l 4kW) via spare solar, by using timers to turn them on sequentially. Your 7700W array, assuming it's north-facing, would probably do fine in decent weather if you do the same with your time-switches.

I'm pretty sure you'll be pleased with your results since you look to be setting up a nice system.

(Anecdotally: I've just added a second paralleled 5kW Sunsynk to my own system [Deye is the Sunsynk OEM], just like you're about to get, along with an extra 10 panels, and have been beyond impressed with the results; even on cloudy days. Oversizing like you're doing - in moderation! - is absolutely the way to go).

 

14 minutes ago, Kory said:

Thanks for this. The final question is we have lived in this house for 8 years and haven’t changed the geyser or worked on it ever. I am not sure if there has been any significant improvements in geyser technology. The previous owner of the house wasn’t one for buying the very best of things, though the house was liveable we have spent quite a bit of time and money doing quality improvements. My question is over the past 8 years has there been any changes or improvement in geyser technology? Would we benefit from a more recent electric geyser in terms of energy efficiency? Yes our system will cover the geyser especially if we use a timer to ensure it heats during the day mainly. Ultimately,  I am opting for oversizing our solar system to cover the geyser rather than buying a solar geyser. So the plan is to in the near future change our two geysers to the most energy efficient ones we can get and use the system to power it. Currently I know we have a 150lt geyser for our 1 bedroom granny flat- I plan to change that to a 100lt as the maximum occupancy for the flat is 2. We have occasional had 3/4 guests but that’s under special circumstances. 

 

7 minutes ago, Kory said:

Thanks for this. The final question is we have lived in this house for 8 years and haven’t changed the geyser or worked on it ever.

Hmmmm.... get the anode checked. That won't cost much, and if you get it changed in time then it will extend the life of your geyser.

7 minutes ago, Kory said:

I am not sure if there has been any significant improvements in geyser technology. The previous owner of the house wasn’t one for buying the very best of things, though the house was liveable we have spent quite a bit of time and money doing quality improvements. My question is over the past 8 years has there been any changes or improvement in geyser technology? Would we benefit from a more recent electric geyser in terms of energy efficiency? Yes our system will cover the geyser especially if we use a timer to ensure it heats during the day mainly. Ultimately,  I am opting for oversizing our solar system to cover the geyser rather than buying a solar geyser. So the plan is to in the near future change our two geysers to the most energy efficient ones we can get and use the system to power it. Currently I know we have a 150lt geyser for our 1 bedroom granny flat- I plan to change that to a 100lt as the maximum occupancy for the flat is 2. We have occasional had 3/4 guests but that’s under special circumstances. 

I would think that new geysers now are better insulated, so heat losses are reduced.

The most economical way to heat water electrically is with a heat pump. I have a heat pump (I had it before I got solar). They take less power and run for less time to heat the same amount of water. I can run mine as a backed up load, so if the sun doesn't shine or if I want it heated early in the morning (and I do) then I have no problems - even if there's no grid.

My heat pump is 13 years old now. I would think that the new ones are more efficient because of improvements in motor technology and the use of different gasses that are more compressible and so can move more heat (or need less power to compress). 

Get your geyser insulated. I have the outlet pipes and the pipes between the geyser and the heat pump insulated. And I have a thick ass "blanket" on the geyser. 

If your routines allow you to heat water only or mostly during the day then you are heating it for free. Win! With any sun-driven technology you have to literally learn to make hay whilst the sun shines. Not just heating water: Your pool pump, your dishwasher, other appliances.... run them whilst the sun is up. That also means you can stretch your batteries further when the sun is down.

Don't overheat the water. Some people turn the thermostat all the way up and then have to add lots of cold water - they've overheated.

 

What am I missing ?

Multiplus II 48/5000/70-50 230v x 1

Freedomwon etower e5000 x 1 

555w panel x 12

MPPT 250/70 x 1

Cerbo GX x 1 

Smartshunt x 1

 

I.E. what else do I need before I can call the installer ? 

52 minutes ago, Franamtb said:

What am I missing ?

Multiplus II 48/5000/70-50 230v x 1

Freedomwon etower e5000 x 1 

555w panel x 12

MPPT 250/70 x 1

Cerbo GX x 1 

Smartshunt x 1

 

I.E. what else do I need before I can call the installer ? 

It is not that simple if you want forum members to accurately advise if the above shopping list is adequate. At least a discusdion in words of your:

1. Load profile

2. Orientation of your roof

3. Load split( essential/ non essentials)

4. Your geographic location.

5. But last not least tell us n bit of yourself as a fairly new member.

Welcome to the forum.

33 minutes ago, TaliaB said:

It is not that simple if you want forum members to accurately advise if the above shopping list is adequate. At least a discusdion in words of your:

1. Load profile

2. Orientation of your roof

3. Load split( essential/ non essentials)

4. Your geographic location.

5. But last not least tell us n bit of yourself as a fairly new member.

Welcome to the forum.

Thanks 

 

No idea of load profile but I won't put the geyser under it for starters. 2 freezers 1 fridge , some lights ( all LED) , 2 laptops almost 12hrs daily , and then other appliances here and there. 

 

Panels will be facing North with no shade until about 17:00 in winter 18:00ish in summer.

 

Essentials are the fridge and freezers and maybe some lights.

 

Location is central centurion , 300 days good sun and then maybe 50 days proper kak weather throughout the year.

 

I'm a young male that wants to pay my father rent but he refuses to accept money from me so I'm going to have this system installed while he's on vacation, maybe sooner. 

 

Idea is to keep the house as normal as possible during loadshedding but also hopefully cut the elec bill by 50/40% 

Latest Bill says R 1 562.45 ex elec for month of April 

38 minutes ago, Franamtb said:

No idea of load profile but I won't put the geyser under it for starters. 2 freezers 1 fridge , some lights ( all LED) , 2 laptops almost 12hrs daily , and then other appliances here and there. 

A good start is your electricity bill. Not the rands, but the kWh consumed. You should be able to work out an average consumption, maybe 2 (summer and winter) if you care to spend a bit more time. This is imperfect, but it's a start.

Also tell us where you live and who you get electricity from. Why do I ask about this? Well, in Johannesburg, which is where I live, most of us are supplied by City Power. A recurring theme is people getting solar installed and then finding that they are still paying a grand for electricity every month. This is because of the City's tariffs. They're still saving, but they expected to see a nice round zero on the bill for electricity. Ain't going to happen because of the various fixed charges that are part of the default tariff. But maybe there is another tariff you can switch to.

If you want to feed back in to the grid to get credits, don't just do it. It can cause problems with the meter, especially pre-paid meters. If you want to feed back do some homework. You will need to register your system with Eskom or with the City (whichever is applicable) and they may need to upgrade or replace your meter. There will be costs attached to this, and the price at which you sell electricity back will be a lot lower than the price at which you buy. I don't feed back (even though my system is registered) because the tariffs (in Johannesburg)  make that unattractive and because I'd have to work the inverter harder.
 

Edited May 9, 20242 yr by Bobster.

3 minutes ago, Franamtb said:

Latest Bill says R 1 562.45 ex elec for month of April 

Tariffs differ from city to city. What is more helpful is how much electricity you consume, because that's what you're going to try and provide with your system. See my post just before this one.

9 minutes ago, Bobster. said:

Tariffs differ from city to city. What is more helpful is how much electricity you consume, because that's what you're going to try and provide with your system. See my post just before this one.

From the past 6 moths bills it seems it seems to however between 790 units to 920 units ( medium 3 bed/2 bath house) 

 

I'm sure that will rise 20/30% in winter 

 

Bills say City of Tshwane 

 

I won't feed back to grid. I'm also aware that I won't make the power bill disappear and there still another 1390 monthly that won't influenced by a solar setup. if I can just make the invoice 150/300 zars a month then it will go a long way. 

Edited May 9, 20242 yr by Franamtb
spelling

7 hours ago, Franamtb said:

What am I missing ?

Multiplus II 48/5000/70-50 230v x 1

Freedomwon etower e5000 x 1 

555w panel x 12

MPPT 250/70 x 1

Cerbo GX x 1 

Smartshunt x 1

 

I.E. what else do I need before I can call the installer ? 

Ok now that we have a better picture of your needs we can give some advice. Back to your original question you cover basically everything equipment wise but there is quite some installation materials and protection devices not on the list. Would you leave that up to the installer?

Your parents place has quite a moderate power consumption profile so definetly you will gain from having the inverter on the essential load side. To remember the longer you can run the inverter between solar and battery without using utility the more saving you will achieve. You are planning a decent solar array so daytime is taken care of but should you manage with 5kwh battery for night times you will make a big dent in the utility bill.

Also try to do geyser management by using less hot water and cover geyser with insulation blanket as geysers are a big part of the expense on the utility bill.

3 minutes ago, TaliaB said:

so try to do geyser management by using less hot water

@Franamtb Idea for futher saving: Your parents shower in hot water and you take a cold shower 🤣🤣

16 minutes ago, TaliaB said:

Ok now that we have a better picture of your needs we can give some advice. Back to your original question you cover basically everything equipment wise but there is quite some installation materials and protection devices not on the list. Would you leave that up to the installer?

Your parents place has quite a moderate power consumption profile so definetly you will gain from having the inverter on the essential load side. To remember the longer you can run the inverter between solar and battery without using utility the more saving you will achieve. You are planning a decent solar array so daytime is taken care of but should you manage with 5kwh battery for night times you will make a big dent in the utility bill.

Also try to do geyser management by using less hot water and cover geyser with insulation blanket as geysers are a big part of the expense on the utility bill.

Geyser I'm going to ask the electrician about ( have them coming Saturday to quote on install , wiring disconnects rails ect ect ) 

 

Geyser I'm thinking of putting on a timer, 4am to 8am and 16:00 - 20:00 

 

That covers all the needs but the first slot will be without sun and probably half of the second slot so little bit concerned about the battery there.

 

I'm going to ask the sparkie if he can fit monitoring equipment so i can see the usage for may and june on different circuits and to see if the 3kw unit will just be a fail from the start 

 

The easi solar 48/3000 35-32 mppt 250/70 seems like a better quicker solution given the load will only decrease in time , my brother and self are going to buy a house start of 2026 and then the usage will be just the parents. 

 

I'm planning the same 5kwh batt and then 6/8 panels with the above device. 

On 2024/05/09 at 3:05 PM, Franamtb said:

Geyser I'm thinking of putting on a timer, 4am to 8am and 16:00 - 20:00 

If the HWC will run off the inverter, then you should probably heat it when solar is plentiful, rather than early morning/later afternoon, when the sun won't be doing too much anymore, ideal would be if you could see whether the HWC would still be warm enough by morning, to only start heating up, by 10:00, when there should be plenty of solar, I'd think...

ON one of the quotes i have received its got a DC distribution box. 

 

WHats contained in that in is it between the panel and inverter or inverter and DB ? 

 

Also the fuse box , whats contained and what ratings ? 

 

going to be 2 strings of 4 panels , 50v voc on the panels , I'm aware of inline fuses between the panels and what I auume will be the PV input on the inverter. 

On 2024/02/22 at 12:35 PM, Bobster. said:

My heat pump is 13 years old now. I would think that the new ones are more efficient because of improvements in motor technology and the use of different gasses that are more compressible and so can move more heat (or need less power to compress). 

And I had a Kwikot appointed technician come to service it today. He says there's nothing much wrong with it. He gave it a quick clean and cleaned the strainer. And he said that's it. There's no repair work being done on these old units now because they use a gas that's no longer available, and the compressor won't work with the new gas.

Important to this conversation is that he confirmed that the new ones are more efficient, and showed me the remote control capability they now have (app on the phone, control it over the internet).

So now I just wait until my unit fails or loses gas.

On 2024/05/15 at 12:01 PM, Franamtb said:

ON one of the quotes i have received its got a DC distribution box. 

 

WHats contained in that in is it between the panel and inverter or inverter and DB ? 

Sorry you had to wait so long for an answer. The DC box handles the DC from the panels into the inverter. It should include a breaker for each string of panels and surge protectors. All of this has to be kept separate from the AC side of things.