19 hours ago, Zeo786 said:

Thanks for this really helps. 

What is your system if u don't mind  me asking?

It's in my signature:
SunSynk 8kW | 4xHubble AM2 20kWh | 16x400W Seraphim 6.4kWp in 2 strings of 8 | Solar-Assistant | Evacuated Tube Thermosiphon Solar Geyser (300l)

I recently fixed a cottage and that has a small 100l normal geyser - I use a timer on both geysers to use excess solar to heat the water.
Both geysers have an electrical element and thermostat so will only use electricity if below 65C.
The small 100l timer is in the morning, and the Thermosiphon is on from 2pm - uses direct sun to heat first.

We a family of 4 with a tenant in a cottage.

As @Sidewinder said - monitor and load shift.
Smart plugs (monitor power and timers and on/off).
 

 

Edited April 30, 20224 yr by system32

On 2022/04/29 at 9:16 PM, Sidewinder said:

I'd thought I also chip in. 

Family of 4 with 8kwSS & 10kw of bulls. You maybe need to look at the following.

1)Load shifting. Assumimg no feed-in, so you need to maximize your usage during the day. Run highdraw appliances only during day when sun shines. Washing, dishwasher, tumbledryer, etc. In winter the slowcooker works overtime. But then you need to be a stew/soup kind person! We cook/bake meals in the oven from 1pm, and then just reheat for dinner. Rest on gas cooker. 

2)Geyser. You have plenty of solar power, so use it(during the day) . So i have 2 geysers(in series), and a hefty heatpump, takes 350 litre up to 64 deg, so enough hot water for evening and morning showers for all. 

3)Batteries. 10kW is barely enough (per household) , and you will suffer deficiency during 2 consecutive rainy days. I would recommend 15kW min. Preferably 20 kW per household. 3 batteries will give you 7.5kW of power max, whem solar is not available. 

4)Control. Try and remote control as much as possible, so that you can bypass default setting, e.g. I have an Astute switch for the pool pump, and on cloudy days, when batteries are not full by certain time, i switch off pool pump, no matter where i am. (750W x 8h running saved). So it's about priority - i can skip the pool for 1 day, but not a low battery

5)Monitor. You need a proper system for this (for each system) , also you will get into spots of bother. 

6)Roof/Space. If you have the space for those panels on the main roof, then keep all three inv. together, if distance to flats is not too far. If you roof is not all pointing north, consider using 2 or even 3 dual Mppt inverters, so you can have some east, mostly north and some west, to flatten you generation curve.

Hope some of this is usefull. 

Thanks this has been really helpful.

 

1)i need to clarify so once the batteries are full, whatever they solar is producing can be used to run highdrawing appliances  ovens geysers etc

 

2)the other 2 houses can be considered as 1. It's really small flats.So Not expecting much usage. So I'm hoping the 15kw for both will suffice. To give u an indication the main house is 300sqm and the both flats combined is 160sqm.

 

Thanks definitely going to look at control and monitoring. 

 

 

 

Hi @Zeo786

 

I 100% agree with what @iiznh & @Calvin said.  I would definitely suggest going with a larger single phase if possible, makes more sense as you don't have to worry about getting the phases balanced to maximise your power as the 3 phase inverters are mostly in effect 3 x smaller single phase inverters running in sync to generate a 3 phase signal.  You can run 3 phase devices of a single phase power supply if you use a VSD btw. 

I woudl also suggest that it is a better plan to consolidate & centralise you power as much as possible, I would not have separate solar installs for the borehole & pool and would just manage them centrally. I would also not have separate installs at the cottages. 

As @Sidewinder suggested as well, one of the main issues you will have is controlling your heavy loads so I would definitely agree on having Smart Switches on all your heavy loads, e.g. Pool pump etc.

There are a few extra things that I would suggest that will not cost a lot of money but will make a big difference. 

1. Power monitoring - I would install power monitoring so you know where your power is actually going, there is nothing more frustrating in a large install than have a 4kw load and not knowing where the power is going. I have personal experience with this as one of my tenants had there oven on during load shedding, if I hadn't been able to see where the power was going I would have had to start switching circuits of on my DB Board to try and stop the bleed on my battery 🙂. Emporia Vue 2 is a pretty good option which you can buy of Amazon for about R2.5k. It will monitor 16 circuits on your DB board and they work very well. It does however use the cloud but can be converted if you have the time 

2. I would go a step further than @Sidewinder on the control side and would suggest installing Home Assistant to manage the switching off and monitoring of all the loads. Is open source so the software will not cost you anything, hardware +-R3000 for a decent platform. Main thing is that it will take you some time to work out how everything goes together, there are however lots of guides on the forum and Youtube. 

3. I would put in either DEYE or Sunsynk inverters but only because I have one and know it pretty well. I am sure that there are many other options available that would work. 

FYI - I have a grid connected 8kw Sunsynk with 2 x 6kw BSL batteries and 28 x 455W panels which generates on average 900 - 1250kw/hr per month .

I run a house, cottage, stables and staff kitchen with 4 geysers, a pool, a borehole & a pressure pump and am about 75% off-grid with most of my usage being at night once my batteries to get me through load shedding are flat. 

In regards to the big question about whether to spend to 100k and connect to Eskom or not, I would say a few things. 

- Important to remember that connecting to Eskom will not only be a connection fee but also a monthly fee. 

- Eskom is never going to get any cheaper 

 

I would view the installation as a learning process rather than a fully installed solution out of the box

I would install the 30kw/hr of batteries & the panels that you specced along with a 6.5kva diesel generator as a starting point as you can always charge the batteries with the generator if required. 

When doing the install I would get the installers to leave some space to make it easy to add in extra panels & batteries in the future if required. 

Would give the system a few months to settle down and would review the data to see where I need to add extra capacity if at all. 

Once you have the system installed it is very easy to do the numbers so you know whether it makes financial sense to add extra batteries or not. I suspect that it would make more sense to put up more panels so that you still make sufficient power on lower solar radiation days. 

Until then you will still have the generator to ensure that you do not run out of power and you can configure that to automatically switch the generator on when your batteries reach a low level. 

 

 

My monthly power production

My annual grid usage & production

 

56 minutes ago, Sc00bs said:

Hi @Zeo786

 

I 100% agree with what @iiznh & @Calvin said.  I would definitely suggest going with a larger single phase if possible, makes more sense as you don't have to worry about getting the phases balanced to maximise your power as the 3 phase inverters are mostly in effect 3 x smaller single phase inverters running in sync to generate a 3 phase signal.  You can run 3 phase devices of a single phase power supply if you use a VSD btw. 

I woudl also suggest that it is a better plan to consolidate & centralise you power as much as possible, I would not have separate solar installs for the borehole & pool and would just manage them centrally. I would also not have separate installs at the cottages. 

As @Sidewinder suggested as well, one of the main issues you will have is controlling your heavy loads so I would definitely agree on having Smart Switches on all your heavy loads, e.g. Pool pump etc.

There are a few extra things that I would suggest that will not cost a lot of money but will make a big difference. 

1. Power monitoring - I would install power monitoring so you know where your power is actually going, there is nothing more frustrating in a large install than have a 4kw load and not knowing where the power is going. I have personal experience with this as one of my tenants had there oven on during load shedding, if I hadn't been able to see where the power was going I would have had to start switching circuits of on my DB Board to try and stop the bleed on my battery 🙂. Emporia Vue 2 is a pretty good option which you can buy of Amazon for about R2.5k. It will monitor 16 circuits on your DB board and they work very well. It does however use the cloud but can be converted if you have the time 

2. I would go a step further than @Sidewinder on the control side and would suggest installing Home Assistant to manage the switching off and monitoring of all the loads. Is open source so the software will not cost you anything, hardware +-R3000 for a decent platform. Main thing is that it will take you some time to work out how everything goes together, there are however lots of guides on the forum and Youtube. 

3. I would put in either DEYE or Sunsynk inverters but only because I have one and know it pretty well. I am sure that there are many other options available that would work. 

FYI - I have a grid connected 8kw Sunsynk with 2 x 6kw BSL batteries and 28 x 455W panels which generates on average 900 - 1250kw/hr per month .

I run a house, cottage, stables and staff kitchen with 4 geysers, a pool, a borehole & a pressure pump and am about 75% off-grid with most of my usage being at night once my batteries to get me through load shedding are flat. 

In regards to the big question about whether to spend to 100k and connect to Eskom or not, I would say a few things. 

- Important to remember that connecting to Eskom will not only be a connection fee but also a monthly fee. 

- Eskom is never going to get any cheaper 

 

I would view the installation as a learning process rather than a fully installed solution out of the box

I would install the 30kw/hr of batteries & the panels that you specced along with a 6.5kva diesel generator as a starting point as you can always charge the batteries with the generator if required. 

When doing the install I would get the installers to leave some space to make it easy to add in extra panels & batteries in the future if required. 

Would give the system a few months to settle down and would review the data to see where I need to add extra capacity if at all. 

Once you have the system installed it is very easy to do the numbers so you know whether it makes financial sense to add extra batteries or not. I suspect that it would make more sense to put up more panels so that you still make sufficient power on lower solar radiation days. 

Until then you will still have the generator to ensure that you do not run out of power and you can configure that to automatically switch the generator on when your batteries reach a low level. 

 

 

My monthly power production

My annual grid usage & production

 

Thanks Really Appreciate the time and details. 

 

To understand you correctly its better to have 1 single system for all 3 houses? I just need to monitor my tenants usage.Will i be able to split the single phase and put a meter at each cottage? I want to be able split each unit to have its own db board. And then meter each db board so I can charge a small fee for electricity usage to avoid abuse of the system.

I was thinking of getting a gas oven and stove. So no appliances that heavy draw on the tenants side. 

Also for heating a fire place - which should warm up the 80sqms. So try and limit their usage of high draw appliances.

also which type of appliances are 3 phase appliances? 

Definitely will then add monitoring and the home assistant. It just makes more sense. With the home assistant I can switch off and on loads remotely?

I know the Fusion invertors are made by deyes as well. But I'm looking at all 3 of those brands. Which ever brand has the best support and interface I'll probably go with.

Eskom charge the monthly fee and they now asking nersa to further ask solar users to pay to be connected to the grid. However The cost of running the generator is worrying me. 

Are there any days when your production is 0 for the day? Or what percentage is the worst we get in South Africa. On bad days do we get 25% / 50% production? 

 

I would say on average I get 2-5 days a month where it rains the whole day. It feels longer but here are the graphs to prove that it only feels longer.

January to April. I have a 10kwh battery that is discharged at 80% depth of discharge. So on most days where noone is at home or no washing is done the house will only use 12-15kwh.

 

Edited May 1, 20224 yr by Buyeye

22 minutes ago, Zeo786 said:

Thanks Really Appreciate the time and details. 

 

To understand you correctly its better to have 1 single system for all 3 houses? I just need to monitor my tenants usage.Will i be able to split the single phase and put a meter at each cottage? I want to be able split each unit to have its own db board. And then meter each db board so I can charge a small fee for electricity usage to avoid abuse of the system.

I was thinking of getting a gas oven and stove. So no appliances that heavy draw on the tenants side. 

Also for heating a fire place - which should warm up the 80sqms. So try and limit their usage of high draw appliances.

also which type of appliances are 3 phase appliances? 

Definitely will then add monitoring and the home assistant. It just makes more sense. With the home assistant I can switch off and on loads remotely?

I know the Fusion invertors are made by deyes as well. But I'm looking at all 3 of those brands. Which ever brand has the best support and interface I'll probably go with.

Eskom charge the monthly fee and they now asking nersa to further ask solar users to pay to be connected to the grid. However The cost of running the generator is worrying me. 

Are there any days when your production is 0 for the day? Or what percentage is the worst we get in South Africa. On bad days do we get 25% / 50% production? 

 

I am not an electrician so you would need clarification from a qualified person at what the options are but the way my system works is. 

All power comes in to my property through my Main DB Board. It runs earth leakage for my house and has 40A breaker switches for Sub-DB-Boards at my pool stables and cottage. The Stables and Cottage each have their own earth leakages on their sub-db-boards. 

I monitor the power going to through 16 circuits on my main DB Board which includes the power going to the sub-db boards. 

I have a disk meter for power going to my cottage which I bill my tenant for. I take a picture of the reading at the beginning of each month and minus that from the next months reading to get the monthly usage.  

Only 3 phase item I have is my water pressure booster pump that is on a VSD that runs of single phase.

Borehole pumps can be 3 phase as well which are usually better for solar but I have a 2kw single phase running of my 8kw Sunsynk without any issues (I do have grid backup though).

Fusion is through a different local supplier I think. DEYE is essentially the same as Sunsynk just different software, I would go with the Sunsynk though, support is very good and the price difference is usually negligible. 

Generator Running costs - 

Macafrica 5kw generator - 

https://www.adendorff.co.za/product/mac-afric-6-5-kva-5-kw-standby-enclosed-type-diesel-generator-220v-single-phase/ 

Quotes the fuel usage @ Fuel consumption – 1.67 l/ph @ full load

At a ruff calculation  say the generator is using 1.5ltr/hr  @ R23/ltr  = +-R35/hr  @ 3.5kw load = R10/KWh for diesel power (should be a pretty safe number) 

Regarding production and taking into account the really bad conditions we have had recently for solar. These are my figures for the last month:

If you have the system in place and finding that you need to run the generator more often than you want o it will be relatively easy to do the numbers and work out whether it it is better to add more batteries or more panels . Until you actually know what your requirement is though it is very difficult to predict. 

It sounds like your two main users of power will be your borehole and your pool.  I use the solar forecasting in Home Assistant to automatically decide whether to switch the pool on for the day or not. If it is going to be overcast the pool doesn't switch on.  The borehole also doesn't usually need to switch on every day so if you build in some intelligence into your tank level monitoring you could automate that so you are not pumping when using your battery power but will pump before you run out of water. Are you going to have a pressure pump or are you going to use a tank stand? 

Other thing to consider is your panel layout, an East/West split would probably be best. Gives you good power in the mornings and evenings and over a longer period than a pure north facing array(although slightly less power altogether) . You can also overwatt the panels, the max solar power the 8kw Sunsynk will produce is 10kw but I have 12kw of panels on my system in an East/ West Split as an example.   

 

 

 

@Zeo786 Where is your house BTW? 

33 minutes ago, Buyeye said:

I would say on average I get 2-5 days a month where it rains the whole day. It feels longer but here are the graphs to prove that it only feels longer.

January to April. I have a 10kwh battery that is discharged at 80% depth of discharge. So on most days where noone is at home or no washing is done the house will only use 12-15kwh.

 

Thanks for this. 

What's you pv size if don't mind me asking?

24 minutes ago, Zeo786 said:

Thanks for this. 

What's you pv size if don't mind me asking?

I have 16 360watt panels in 2 strings of 8 going to a growatt spf5000es and a dyness powerbox 10kwh.

All lights are LED, hot water is a taken care of by a 5kw geyser heat pump which replaced a 4kw electric element I would say effectively cut down my usage by half.

I have a newish ceramic stove(AEG) so it's going to be atleast 10 years before that needs replacing. To allow me to cook when there is no grid I got an airfryer and a Mi induction plate. The Mi induction plate has been the most impressive appliance, I replaced my electric kettle with it. It heats water just as fast but doesn't put as much load on the inverter. I can also use it to cook rice or pasta or just fry eggs.

 

One more thing about the induction plate is that you will only use full power to boil water for tea or something. To fry eggs anything higher than 30% power burns most foods.

Edited May 1, 20224 yr by Buyeye

34 minutes ago, Sc00bs said:

I am not an electrician so you would need clarification from a qualified person at what the options are but the way my system works is. 

All power comes in to my property through my Main DB Board. It runs earth leakage for my house and has 40A breaker switches for Sub-DB-Boards at my pool stables and cottage. The Stables and Cottage each have their own earth leakages on their sub-db-boards. 

I monitor the power going to through 16 circuits on my main DB Board which includes the power going to the sub-db boards. 

I have a disk meter for power going to my cottage which I bill my tenant for. I take a picture of the reading at the beginning of each month and minus that from the next months reading to get the monthly usage.  

Only 3 phase item I have is my water pressure booster pump that is on a VSD that runs of single phase.

Borehole pumps can be 3 phase as well which are usually better for solar but I have a 2kw single phase running of my 8kw Sunsynk without any issues (I do have grid backup though).

Fusion is through a different local supplier I think. DEYE is essentially the same as Sunsynk just different software, I would go with the Sunsynk though, support is very good and the price difference is usually negligible. 

Generator Running costs - 

Macafrica 5kw generator - 

https://www.adendorff.co.za/product/mac-afric-6-5-kva-5-kw-standby-enclosed-type-diesel-generator-220v-single-phase/ 

Quotes the fuel usage @ Fuel consumption – 1.67 l/ph @ full load

At a ruff calculation  say the generator is using 1.5ltr/hr  @ R23/ltr  = +-R35/hr  @ 3.5kw load = R10/KWh for diesel power (should be a pretty safe number) 

Regarding production and taking into account the really bad conditions we have had recently for solar. These are my figures for the last month:

If you have the system in place and finding that you need to run the generator more often than you want o it will be relatively easy to do the numbers and work out whether it it is better to add more batteries or more panels . Until you actually know what your requirement is though it is very difficult to predict. 

It sounds like your two main users of power will be your borehole and your pool.  I use the solar forecasting in Home Assistant to automatically decide whether to switch the pool on for the day or not. If it is going to be overcast the pool doesn't switch on.  The borehole also doesn't usually need to switch on every day so if you build in some intelligence into your tank level monitoring you could automate that so you are not pumping when using your battery power but will pump before you run out of water. Are you going to have a pressure pump or are you going to use a tank stand? 

Other thing to consider is your panel layout, an East/West split would probably be best. Gives you good power in the mornings and evenings and over a longer period than a pure north facing array(although slightly less power altogether) . You can also overwatt the panels, the max solar power the 8kw Sunsynk will produce is 10kw but I have 12kw of panels on my system in an East/ West Split as an example.   

 

 

 

I'm in Johannesburg. 

the 8kw sunsynk invertor is 10.4kw max. So if i overwatt the panels to say 12Kw will the inverter just cut the extra supply?

Going to be putting in a pressure pump. So I'm assuming that's the other high drawing item.

 the roof will have mainly north east, north and west faces. And some east faces. This is across all 3 houses. 

1 hour ago, Zeo786 said:

I'm in Johannesburg. 

the 8kw sunsynk invertor is 10.4kw max. So if i overwatt the panels to say 12Kw will the inverter just cut the extra supply?

Going to be putting in a pressure pump. So I'm assuming that's the other high drawing item.

 the roof will have mainly north east, north and west faces. And some east faces. This is across all 3 houses. 

I am also in Johannesburg, Midrand. 

Regarding over watting you inverter, you will loose the extra power on those high production level days, but will make extra power on the lower days. 

When you get your pressure pump, make sure it is one with a VSD (Variable Speed Drive), you set the desired pressure and it will only drive the motor as fast as it needs to go to keep the pressure.  They also do not generally require a lot of power to start the motor as they have a soft start but if you have a leaky water system they tend to switch on/off quite a bit. Mine uses about 2kw/hr a day but suspect that it is not an optimum setup and it gets switched off at night after 10 and we just use gravity feed. 

55 minutes ago, Sc00bs said:

I am also in Johannesburg, Midrand. 

Regarding over watting you inverter, you will loose the extra power on those high production level days, but will make extra power on the lower days. 

When you get your pressure pump, make sure it is one with a VSD (Variable Speed Drive), you set the desired pressure and it will only drive the motor as fast as it needs to go to keep the pressure.  They also do not generally require a lot of power to start the motor as they have a soft start but if you have a leaky water system they tend to switch on/off quite a bit. Mine uses about 2kw/hr a day but suspect that it is not an optimum setup and it gets switched off at night after 10 and we just use gravity feed. 

Will make sure it has a VSD. 

Tell me for gravity fed how high does it have to be off the ground?

1 hour ago, Zeo786 said:

Tell me for gravity fed how high does it have to be off the ground?

Doesn't really have to be that high, I have a 20,000ltr tank that is sitting on the ground. Water level is about 3mtr above ground level when full and that is sufficient to fill toilets etc, not enough to have a shower though. 3mtr height is 0.3bar pressure (I love the metric system)🙂  

Something like this should do the job as a pressure pump

https://www.builders.co.za/Water-Storage-%26-Filtration/Water-Tank-Pumps/JoJo-Tanks-Variable-Speed-Booster-Pump-(0-75kW)/p/000000000000716601?gclid=Cj0KCQjw37iTBhCWARIsACBt1Ixo5YMpBSaEMiZlEuXSSJl5aaDIhws4iCmBLDDYKyrhSpqNvICxQwMaAkdnEALw_wcB

12 hours ago, Zeo786 said:

Thanks Really Appreciate the time and details. 

 

 

Eskom charge the monthly fee and they now asking nersa to further ask solar users to pay to be connected to the grid. However The cost of running the generator is worrying me. 

Are there any days when your production is 0 for the day? Or what percentage is the worst we get in South Africa. On bad days do we get 25% / 50% production? 

 

Zeo786 you have been given a lot of spot on replies on a lot of pointers.

Some questions were perhaps not answered. If being off grid a generator will be essential even if it cost quite a bit to run. R8-R10 an hour but hopefully not too many sessions per year. 

I looked at your 29 x 545W panels. For JHB this should give you at maximum if you use of ALL the PV that you can get an average of the load of 50kwh per day. In summer you might get a maximum of 63kwh per day. The real problem why you will need a genny is that your day time load is 25kwh a day so you will have a lot of wasted PV. Storage for those bad days and specially when you have 3-5 days of rain. You will find on some days if you have discharged your batteries by 80% that you might only recharge then by 20% of what you used. 

Some bad days you might get as little as 10-15% of the summer 63kwh a day. This is where the genny comes into play. On 16 Apl we got a maximum of 5% and 3,9,10 and 17 Apl about 15% of the daily average. Refer to the graph below. Thus you might only get 3kwh which gives a major short fall and no battery charging will take place as you are going to use it all for scaled down load. These calcs are based on a annual 4kwh/kw of panels providing maximum PV facing north. In your case your daily maximum will be less due to your orientation of panels. Summer yield an average of 5kwh/kw of panels installed.

If you can switch some of your 750/750kwh load split between sun period vs no sun it will limit the use of a genny. If you moved the load to be 1000kwh during the day per month and 500kwh after sunset you will still need R100 000 for batteries. Sorry to be the bearer of bad news but being off grid when you have a daily use of 50kwh becomes very expensive.

Stats for April.

 

 

Edited May 1, 20224 yr by Scorp007

7 hours ago, Sc00bs said:

Doesn't really have to be that high, I have a 20,000ltr tank that is sitting on the ground. Water level is about 3mtr above ground level when full and that is sufficient to fill toilets etc, not enough to have a shower though. 3mtr height is 0.3bar pressure (I love the metric system)🙂  

Something like this should do the job as a pressure pump

https://www.builders.co.za/Water-Storage-%26-Filtration/Water-Tank-Pumps/JoJo-Tanks-Variable-Speed-Booster-Pump-(0-75kW)/p/000000000000716601?gclid=Cj0KCQjw37iTBhCWARIsACBt1Ixo5YMpBSaEMiZlEuXSSJl5aaDIhws4iCmBLDDYKyrhSpqNvICxQwMaAkdnEALw_wcB

Last question do you have a recommended installer?

35 minutes ago, Scorp007 said:

Zeo786 you have been given a lot of spot on replies on a lot of pointers.

Some questions were perhaps not answered. If being off grid a generator will be essential even if it cost quite a bit to run. R8-R10 an hour but hopefully not too many sessions per year. 

I looked at your 29 x 545W panels. For JHB this should give you at maximum if you use of ALL the PV that you can get an average of the load of 50kwh per day. In summer you might get a maximum of 63kwh per day. The real problem why you will need a genny is that your day time load is 25kwh a day so you will have a lot of wasted PV. Storage for those bad days and specially when you have 3-5 days of rain. You will find on some days if you have discharged your batteries by 80% that you might only recharge then by 20% of what you used. 

Some bad days you might get as little as 10-15% of the summer 63kwh a day. This is where the genny comes into play. On 16 Apl we got a maximum of 5% and 3,9,10 and 17 Apl about 15% of the daily average. Refer to the graph below. Thus you might only get 3kwh which gives a major short fall and no battery charging will take place as you are going to use it all for scaled down load. These calcs are based on a annual 4kwh/kw of panels providing maximum PV facing north. In your case your daily maximum will be less due to your orientation of panels. Summer yield an average of 5kwh/kw of panels installed.

If you can switch some of your 750/750kwh load split between sun period vs no sun it will limit the use of a genny. If you moved the load to be 1000kwh during the day per month and 500kwh after sunset you will still need R100 000 for batteries. Sorry to be the bearer of bad news but being off grid when you have a daily use of 50kwh becomes very expensive.

Stats for April.

 

 

Thanks for the reply.

Are you working on 4 hours a day production? 545 x 29 = 15805 x 4 = 63? I used 4.5 to 5 hours a day production.

I think when looking at the graphs, it's becoming ever likely I'll have tobhave Eskom as a backup. Even if it's just for my essential loads. 

If I have 2 x 8kw Sunsynk invertors in parallel, what Eskom supply would I need? Should I just make sure the supplies amps can cover my essential loads across all 3 houses?

I think because the house is not built my usage is just an assumption at the moment. Like @Sc00bs mentioned i need to relook at the system a few months in. 

 

I don't know if I would connect to Eskom straight away. I think that I would keep it as a back up plan. 

R100k buys a lot of diesel!

If you are going to go gas for your water heaters and stoves, those are  major users of power, apart from the pool and the borehole (my suggestion, buy an extra water tank so you only have top pump when there is sun) I really do not think that you will be using the generator very often of you have 30kr/hr of storage. 

Again, once you have the system installed and running you will have a much better idea of were your system needs some boosting. 

One thing, are the comms on the batteries you were looking at compatible with the Sunsynk inverters? 

Yes the 4 overall per year is the full power of the PV yield in Gauteng and 5 the hours in summer. A few best days in summer can yield 6 just as a few bad days in summer can yield only 5% of the normal yield.

The 63kwh is based on 80% of the 29x545Wx5hrs due to the irradiance in Jhb in summer if no PV is wasted. Not easy to achieve. You will see how most people have wasted PV once the battery is charged.

I prefer working from these figures before one looks at how to best use PV and doing things in an efficient way.

Edited May 2, 20224 yr by Scorp007

10 hours ago, Sc00bs said:

I don't know if I would connect to Eskom straight away. I think that I would keep it as a back up plan. 

R100k buys a lot of diesel!

If you are going to go gas for your water heaters and stoves, those are  major users of power, apart from the pool and the borehole (my suggestion, buy an extra water tank so you only have top pump when there is sun) I really do not think that you will be using the generator very often of you have 30kr/hr of storage. 

Again, once you have the system installed and running you will have a much better idea of were your system needs some boosting. 

One thing, are the comms on the batteries you were looking at compatible with the Sunsynk inverters? 

@Sc00bs I see you trying to get me to stay away from  Eskom. Haha. Can't blame you. I still cant getbover the cost of connection and why I have to pay for their grid. I think Im going to have to run the numbers. There's a R300 connection fee per month. R500 depending on what supply i take.

I'm not sure, I have asked if the alphas can be connected to the sunsynks. Just waiting for a reply. I did see someone systems pic on this forum with an alpha battery. I'll double check. Thanks 

3 hours ago, Scorp007 said:

Yes the 4 overall per year is the full power of the PV yield in Gauteng and 5 the hours in summer. A few best days in summer can yield 6 just as a few bad days in summer can yield only 5% of the normal yield.

The 63kwh is based on 80% of the 29x545Wx5hrs due to the irradiance in Jhb in summer if no PV is wasted. Not easy to achieve. You will see how most people have wasted PV once the battery is charged.

I prefer working from these figures before one looks at how to best use PV and doing things in an efficient way.

Got you. I'll work on the 4 hour worst case scenario.

Can The extra Pv can be used in other ways after the battery is charged? Like If theres loadshedding I can give my neighbor a plug point to do his washing or something 

Edited May 2, 20224 yr by Zeo786

11 hours ago, Sc00bs said:

I don't know if I would connect to Eskom straight away. I think that I would keep it as a back up plan. 

R100k buys a lot of diesel!

If you are going to go gas for your water heaters and stoves, those are  major users of power, apart from the pool and the borehole (my suggestion, buy an extra water tank so you only have top pump when there is sun) I really do not think that you will be using the generator very often of you have 30kr/hr of storage. 

Again, once you have the system installed and running you will have a much better idea of were your system needs some boosting. 

One thing, are the comms on the batteries you were looking at compatible with the Sunsynk inverters? 

Here's the answer 

 

"Question: 

Can I use a Fusion 10kw invertor with this battery? Or does it have to be alpha or goodwe invertors?

 

Answer: 

Hi Zain, we have it in writing from Alpha ESS that they will not honour any warranties if you use the battery with this inverter (or a Sunsynk or Deye)"

 

So I'll need to look at goodwe or alpha invertors. Or another battery make.

I think I would just look for another battery that will communicate directly with the Sunsynk inverter. 

Speak to @Leshen about installation,  and the guys from the Powerforum store for supply. Their pricing seems to usually be pretty good. 

 

 

21 hours ago, Zeo786 said:

Here's the answer 

 

"Question: 

Can I use a Fusion 10kw invertor with this battery? Or does it have to be alpha or goodwe invertors?

 

Answer: 

Hi Zain, we have it in writing from Alpha ESS that they will not honour any warranties if you use the battery with this inverter (or a Sunsynk or Deye)"

 

So I'll need to look at goodwe or alpha invertors. Or another battery make.

@Zeo786

 

Is there any chance your can share the writing with me ? We have 2 x Alpha Batteries connected to a Sunsynk and we have some problems with the setup. Would like to take it up with the installer.

 

22 hours ago, Zeo786 said:

Can The extra Pv can be used in other ways after the battery is charged? Like If theres loadshedding I can give my neighbor a plug point to do his washing or something 

Just buy a big pool heater,  when you haver extra power you just heat the pool up 🙂 

I would advise against picking a certain battery due to promises made on their specsheet.

All lithium batteries are built from cells produced in China from about 8 main manufacturers. Their spec-sheets mention 6000 cycles under ideal circumstances, losing 20% capacity. If anyone promises you more, then be wary.

Lithium batteries will still be operational after the 6000 cycles, they will simply have reduced capacity. Who knows, you might get 10 000 cycles out of them. I predict that with the EV market maturing we will have much cheaper batteries in a few years that might offer far greater cycles. 

The batteries are only as good as the battery builder, will the company still be around in 10 years? Do we have a track record of them honouring warranty claims? Do they have a bunch of small print to get them exempted from the battery warranty. 

Stick with batteries with good support and a good track record that has been around for a few years, look at reviews and before you look at promises

Edited May 3, 20224 yr by iiznh
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