Small solar advice (5KVA hybrid system)

[denmendez65]

Exactly. Fanless still comes with same warranty as fan type though. I’ll try find a will prouse video I saw a while back of a silent inverter he was testing and said it was a game changer for him.

Yeah, and even if there is no larger size than 5kW you can always parallel them. I do actually like them. I just don't know how well natural cooling works compared to using a fan. The heatsink must be huge.

 

[wingnut771]

Yeah, and even if there is no larger size than 5kW you can always parallel them. I do actually like them. I just don't know how well natural cooling works compared to using a fan. The heatsink must be huge.

It is huge afaik, basically the whole back I think is the heatsink.

Heres the video, goodwe HV 11kW:

 

[denmendez65]

It is huge afaik, basically the whole back I think is the heatsink.

Heres the video, goodwe HV 11kW:

Clever, they go HV rather than 48V as it's less current and hence less heat. I wonder why they don't standardise home solar on, say, 72V or even 96 on the battery side. I mean, I think it was 120Vdc, which is a bit of a safety concern, but you don't see the typical homeowner messing around with their batteries.

Less current means less thick cable and fewer losses, which means cheaper. And it seems to help a lot with the heat on the inverter itself. Why invert from 48 to 230 when you can do 96 to 230?

 

[wingnut771]

Clever, they go HV rather than 48V as it's less current and hence less heat. I wonder why they don't standardise home solar on, say, 72V or even 96 on the battery side. I mean, I think it was 120Vdc, which is a bit of a safety concern, but you don't see the typical homeowner messing around with their batteries.

Less current means less thick cable and fewer losses, which means cheaper. And it seems to help a lot with the heat on the inverter itself. Why invert from 48 to 230 when you can do 96 to 230?

I think it’s a danger thing. Handling 48V won’t kill you, the HV systems will. Also, being legacy tech, much more support. You see how he complained how expensive the batteries were.

 

[isie]

Hi,

Looking at a small 5KVA hybrid solar system for my folks essentials.

Was looking at a Deye 5KVA hybrid inverter with a 5.12KWH Deye battery and 6 x 500ish panels on a zinc roof.
Installer recommended to consider a Luxpower hybrid inverter instead to keep costs more reasonable.

They are quite happy to continue with municipal power especially since loadshedding has reduced, however the practicality of powering the essentials without having to waste petrol on the current generator is attractive.

Advice?

The goal was to run roughly half the house on solar (kitchen, dining area, second lounge, spare bedroom+bathroom) plus the house lights.
5KVA would be suitable as all that is on one 4.5kva plug circuit which has never tripped, and the lights are all LED and don't take more than more than 350w in total if the sums from all the boxes are correct (they're never all on anyway).

Municipal only used on overcast days when the batteries would be down to their recommended minimum and not enough sun to top up. Using various plug watt-meters I calculated their 4pm-to 8am usage to be around 3-4KWH.



Was recommended the hybrid, I was under the impression it's needed to have access to municipal power.
The other type I saw was the full off-grid inverter which is cheaper as it doesn't connect to the municipal grid at all but quite limited to a max of 6 panels only.

If going Luxpower make sure its the model that can blend AC/DC sources trust me that will save you a lot more especially as you still keeping Municipal trust me on this so dont skimp on the full off grid.

as for Deye vs luxpower - Im a deye fanboy but Lux is good let your budget decide what you can get but ill be honest rather go 6 to 8 KVA you can hook up at least the oven and stove maybe AC or pool pump on the 6 and a geyser (or 2 ) on a 8 - even on 5 try to connect the whole house lights ,plugs etc and just leave out the High wattage stuff (Geyser, Stove, Oven, pool AC etc).

remember you run as much as your home from the inverter as you can and let it decide where the power will come from

 

[wingnut771]

If going Luxpower make sure its the model that can blend AC/DC sources trust me that will save you a lot more especially as you still keeping Municipal trust me on this so dont skimp on the full off grid.

as for Deye vs luxpower - Im a deye fanboy but Lux is good let your budget decide what you can get but ill be honest rather go 6 to 8 KVA you can hook up at least the oven and stove maybe AC or pool pump on the 6 and a geyser (or 2 ) on a 8 - even on 5 try to connect the whole house lights ,plugs etc and just leave out the High wattage stuff (Geyser, Stove, Oven, pool AC etc).

remember you run as much as your home from the inverter as you can and let it decide where the power will come from

Leaving the geyser off that stuff is madness as that is 90% of your bill but I agree on the blending part.

 

[denmendez65]

I think it’s a danger thing. Handling 48V won’t kill you, the HV systems will. Also, being legacy tech, much more support. You see how he complained how expensive the batteries were.

12V was legacy at one stage, then 24, and now 48 is the standard. 230AC can technically kill you, so I don't see why 96 should be avoided. Only a qualified electrician should be handling the stuff anyway, and not the homeowner with YouTube videos unless he is willing to accept the risk. Heck, there is already some 400V from the panels.

 

[wingnut771]

12V was legacy at one stage, then 24, and now 48 is the standard. 230AC can technically kill you, so I don't see why 96 should be avoided. Only a qualified electrician should be handling the stuff anyway, and not the homeowner with YouTube videos unless he is willing to accept the risk. Heck, there is already some 400V from the panels.

DC is more dangerous than AC. I don't think a qualified electrician is qualified to work with HV DC.

 

[denmendez65]

Leaving the geyser off that stuff is madness as that is 90% of your bill but I agree on the blending part.

Yeah, but I am sure even the Nava does it. Some of these features that used to be only on the high-end models are now on the cheapies.

The Ecco and MUST, for example, run off solar alone, off battery alone and if overloaded switch immediately to the grid in passthrough. I am certain even the very cheap of the cheap, like Nava, does that also. Maybe not the running off solar alone.

 

[NR7]

Leaving the geyser off that stuff is madness as that is 90% of your bill but I agree on the blending part.

Don’t think this small system would suit my dumb 3kw Kwikot geyser.

MyBB did a solar article couple years that's quite useful for me

How much money we saved with a week of solar power

Despite its modest size, the recently installed solar system of one of MyBroadband’s employees has supplied over 70% of their electricity requirements in a week.

mybroadband.co.za

Very similar system to what I'm considering, generated 7.5KWH PV on a cloudy day and 10.5KWH sunny.

Half our house plugs plus all the lights will be about 7KWH per day.

In winter we can use around 770KWH, with Ekurhuleni's prices per unit going up massively once you breach 600KWH (the 100KWH to 700 costs R442 and remaining 70KWH to 770 cost R801) so the solar would make a big difference.

 

[denmendez65]

DC is more dangerous than AC. I don't think a qualified electrician is qualified to work with HV DC.

Well, that's debatable. I am yet to see conclusive evidence of that, as the guys in the industry say AC and the others DC. DC supposedly grabs you and doesn't let go, whereas AC does.

A quick look at the thresholds and it says 50VAC can kill you, but you need at least 120VDC to get the same effect. I have been zapping myself wth 110 to 130VDC for years now, and it doesn't bite as hard as 110AC. So I doubt a 96V battery, even when charging, will do enough.

 

[denmendez65]

DC is more dangerous than AC. I don't think a qualified electrician is qualified to work with HV DC.

What range is HV DC? Can we really count anything over 48 as HV?

 

[NR7]

I don't know the Deye, but Goodwe and Solis don't have a surge rating. I would assume the Deye also. Seems to be a design feature of the Fanless inverters. Surge handling is very important. Tripping every time you start a vacuum cleaner or some pump (maybe even a fridge) is not something nice.

Found that on the Deye spec sheet it says say "Peak Power (off-grid) (W)" to be "2 times of rated power, 10s", it's the same wording on the 5 8 and 12.

I assume that would mean it could handle a startup draw although my small load peak is below the 5kva of the Deye system anyway else we would be tripping the 4.5kva breaker every day.

 

[denmendez65]

Found that on the Deye spec sheet it says say "Peak Power (off-grid) (W)" to be "2 times of rated power, 10s", it's the same wording on the 5 8 and 12.

I assume that would mean it could handle a startup draw although my small load peak is below the 5kva of the Deye system anyway else we would be tripping the 4.5kva breaker every day.

For the fanless one? I tried looking for the silent fanless one, but couldn't find it on their site. If it says so, then that is actually nice and might be worthwhile. Any pricing for the fanless one?

 

[NR7]

For the fanless one? I tried looking for the silent fanless one, but couldn't find it on their site. If it says so, then that is actually nice and might be worthwhile. Any pricing for the fanless one?

I assume it is fanless as it says "Natural cooling" lol.

This was the listing at a supplier I saw : https://solarwarehousesa.com/produc...uding-wifi-dongle?_pos=1&_sid=631f4a34d&_ss=r

 

[denmendez65]

I assume it is fanless as it says "Natural cooling" lol.

This was the listing at a supplier I saw : https://solarwarehousesa.com/produc...uding-wifi-dongle?_pos=1&_sid=631f4a34d&_ss=r

Looks about right. So the Deye is better than the Goodwe and Solis. But the price is eye-watering . Can buy 3 of those 6.2kW Ecco ones for 1 of the Deye. But you can't beat silent operation, I guess. And i see its 5 year warranty like the Ecco.

 

[isie]

Leaving the geyser off that stuff is madness as that is 90% of your bill but I agree on the blending part.

100% lol you speaking to the 2 geyser in series guy

Don’t think this small system would suit my dumb 3kw Kwikot geyser.

MyBB did a solar article couple years that's quite useful for me

How much money we saved with a week of solar power

Despite its modest size, the recently installed solar system of one of MyBroadband’s employees has supplied over 70% of their electricity requirements in a week.

mybroadband.co.za

Very similar system to what I'm considering, generated 7.5KWH PV on a cloudy day and 10.5KWH sunny.

Half our house plugs plus all the lights will be about 7KWH per day.

In winter we can use around 770KWH, with Ekurhuleni's prices per unit going up massively once you breach 600KWH (the 100KWH to 700 costs R442 and remaining 70KWH to 770 cost R801) so the solar would make a big difference.

get a simple wifi geyser controller they not expensive (if you want to be even more pedantic (i.e me) get one with temp control
but seriously the more you can have on the system the more you will save

 

[wingnut771]

Yeah, but I am sure even the Nava does it. Some of these features that used to be only on the high-end models are now on the cheapies.

The Ecco and MUST, for example, run off solar alone, off battery alone and if overloaded switch immediately to the grid in passthrough. I am certain even the very cheap of the cheap, like Nava, does that also. Maybe not the running off solar alone.

Blending is using 100% solar and when thats not enough, adding/blending in battery/grid power. The cheapies would just cut off solar if load is too much and switch to battery/grid therefore wasting solar.

 

[wingnut771]

Don’t think this small system would suit my dumb 3kw Kwikot geyser.

MyBB did a solar article couple years that's quite useful for me

How much money we saved with a week of solar power

Despite its modest size, the recently installed solar system of one of MyBroadband’s employees has supplied over 70% of their electricity requirements in a week.

mybroadband.co.za

Very similar system to what I'm considering, generated 7.5KWH PV on a cloudy day and 10.5KWH sunny.

Half our house plugs plus all the lights will be about 7KWH per day.

In winter we can use around 770KWH, with Ekurhuleni's prices per unit going up massively once you breach 600KWH (the 100KWH to 700 costs R442 and remaining 70KWH to 770 cost R801) so the solar would make a big difference.

You can change element to 2KW for a R100. That way you still have spare capacity on a 5kW for other loads.

 

[wingnut771]

What range is HV DC? Can we really count anything over 48 as HV?

Anyway, no one is making it so its a moot point.