The Battery Thread (Solar / Inverter)

Speedster

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The_Traveller said:
Using the words of another muppet on this forum, he is talking through his nostrils.

Almost all inverters automatically switch over, with decent transfer time so your electronics won't power off and on.
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Only hybrid inverters automatically switch over. Grid tied inverters don't work during LS, and off-grid inverters need to switch over as they're not connected to the grid.
 
The_Traveller

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Speedster said:
You're going to have to explain this one to me.
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We were talking about off grid inverters not grid tied. Grid tied is a solar application yes?

I've tried/tested and used various brands of Chinese inverters since 2012 and all of them switched over automatically when the council dropped power.

Unless I misunderstood you and you're talking about something else ?
 
Speedster

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The_Traveller said:
We were talking about off grid inverters not grid tied. Grid tied is a solar application yes?

I've tried/tested and used various brands of Chinese inverters since 2012 and all of them switched over automatically when the council dropped power.

Unless I misunderstood you and you're talking about something else ?
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Grid-tied requires grid to operate, so typically a PV setup (or battery with time-shifting of power in peak/off-peak pricing, such as powerwall).

Off-grid has no grid connection, either due to no grid connection being accessible or deciding to cut the municipal/Eskom cord. This can be used as a backup solution for LS.

Anything else is some type of hybrid.
 
TheChamp

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The_Traveller said:
We were talking about off grid inverters not grid tied. Grid tied is a solar application yes?

I've tried/tested and used various brands of Chinese inverters since 2012 and all of them switched over automatically when the council dropped power.

Unless I misunderstood you and you're talking about something else ?
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He is 100% right in theory but in reality the terminology means very little as it is being used so loosely, it's just a waste of time getting bogged down on it.

Off grid in theory means there's no grid, so there's even no option for connecting AC, hence no need for switching over.

Grid tied as he said and hybrid as he said. But with every Tom, Dick and Harry selling solar stuff these terms are used interchangeably, an off grid can simply mean an inverter that can work with no grid connected, not necessarily that it cannot support grid connection.

Instead of confusing yourself with terms it's much simpler to just stick to the spec and tick off the features you want from an inverter.
 
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Drager

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So what is you inverter+battery recommendation based on this:

1. Get through 3 LS of 2h per 24h (battery needs to charge to 100% in 6 hours max)
2. 500W baseline
3. Add a 3000W peak of 20min per day during one LS
4. Not installing solar for v1, if ever
5. Geyser on grid
6. Want an app/graphs
7. Seamless LS handover
 
The_Traveller

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Drager said:
So what is you inverter+battery recommendation based on this:

1. 500W baseline
2. Add a 3000W peak of 20min per day during one LS
3. Get through 3 LS of 2h per 24h
4. Not installing solar for v1, if ever
5. Geyser on grid
6. Want an app/graphs
7. Seamless LS handover
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If you want a cheap basic system... opt for an ellies 3kw inverter and for batteries, I know of a brand called Allgrand that make good quality VRLA Gel batteries, at decent pricing.

I guess all depends on your budget, so best you let everyone know this and you'll get a lot of recommendations
 
Speedster

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Drager said:
So what is you inverter+battery recommendation based on this:

1. Get through 3 LS of 2h per 24h (battery needs to charge to 100% in 6 hours max)
2. 500W baseline
3. Add a 3000W peak of 20min per day during one LS
4. Not installing solar for v1, if ever
5. Geyser on grid
6. Want an app/graphs
7. Seamless LS handover
Click to expand...
As mentioned I'd go Sunsynk 3.6kW with Pylon US2000. Would love to see what alternatives the guys on the forum have in this spec.
 
Drager

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The_Traveller said:
If you want a cheap basic system... opt for an ellies 3kw inverter and for batteries, I know of a brand called Allgrand that make good quality VRLA Gel batteries, at decent pricing.

I guess all depends on your budget, so best you let everyone know this and you'll get a lot of recommendations
Click to expand...
I want quality, so budget is not a factor. Well, not gold plated you know. ;)
 
TheChamp

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The_Traveller said:
If you want a cheap basic system... opt for an ellies 3kw inverter and for batteries, I know of a brand called Allgrand that make good quality VRLA Gel batteries, at decent pricing.

I guess all depends on your budget, so best you let everyone know this and you'll get a lot of recommendations
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He wants the fancy stuff. He has already been quoted on the cheap stuff.
 
Speedster

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Drager said:
Can the US2000 handle a 3.5kW load for 20 minutes? On another forum someone mentioned the US3000 wouldn't be able to do it. (https://thegrotto.co.za/threads/solar-inverter-battery-thread.850/post-71123)
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Good point. You shouldn't be pulling more than 1.2kW from that battery for an extended time. To get up to 3.5kW you're going to need to upsize your battery quite a bit. You'll need at least 3.5kWh from a 1C rated battery (Hubble, Bull) or 7kWh from a 0.5C battery (most of the other brands).

Lead acid does much better with high loads, but your requirements don't allow for sufficient charging time between LS slots.
 
Drager

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Speedster said:
Good point. You shouldn't be pulling more than 1.2kW from that battery for an extended time. To get up to 3.5kW you're going to need to upsize your battery quite a bit. You'll need at least 3.5kWh from a 1C rated battery (Hubble, Bull) or 7kWh from a 0.5C battery (most of the other brands).

Lead acid does much better with high loads, but your requirements don't allow for sufficient charging time between LS slots.
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I hear you, and appreciate the new knowledge, but would love an easy answer like "buy this and you'll be happy" kind of answer. ;)

I'd prefer Lithium.
 
Speedster

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Drager said:
I hear you, and appreciate the new knowledge, but would love an easy answer like "buy this and you'll be happy" kind of answer. ;)

I'd prefer Lithium.
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You're paying a significant premium for those 20 min at 3.5kW. But to answer your question, a Hubble AM-2 is my recommendation for that requirement.
 
Drager

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Speedster said:
You're paying a significant premium for those 20 min at 3.5kW. But to answer your question, a Hubble AM-2 is my recommendation for that requirement.
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Cool, that settles the battery. And a 5kW hybrid inverter? (with pretty pictures)

(btw, my idea is that if I spend this kind of money then LS should never exist for me, that includes being able to make a pizza. Kinda indulgent I know, but I like pizza.)
 
Speedster

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Speedster

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Drager said:
Cool, that settles the battery. And a 5kW hybrid inverter? (with pretty pictures)

(btw, my idea is that if I spend this kind of money then LS should never exist for me, that includes being able to make a pizza. Kinda indulgent I know, but I like pizza.)
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You know how many pizza's you could have Uber deliver for the price of that battery? :giggle:
 
Drager

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Speedster

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Drager said:
I'm a geek. It's worth it.
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Food for thought. Once you've shelled out R50k for your pizza compliant backup system you might want to consider adding some PV. For another R20k-ish you could probably basically go off-grid and never have to pay electricity again (except when the sun doesn't shine for a couple of days).

Another way to tackle the pizza "problem" is to have 2.5kWp PV, which you can add to the 1.2kW from the smaller Pylon battery. You'll save R10k on the battery, and spend R15k on the PV. So for an extra R5k you'll cut your electricity bill by a big chunk. That's assuming you make pizza when the sun shines.
 
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