Loadshedding solutions

[mazambaan]

19 minutes ago, ChrisF said:

 

Nice thought .... practically totally useless.

 

If I may explain why -

Optical, heat and CO fire detectors all detect a "fire".

 

The only "preventative" measure is when wiring or multi-plugs start smouldering this may trigger a fire detector before it becomes an actual fire.  We have had this on some of our projects.   Client was initially annoyed at the "false alarm" ... became VERY HAPPY when they found the smouldering multi plug.

 

Lithium batteries heat up, swell, and then starts burning.

 

LOTS of researh is being done world wide to find ways to early detect this, also to find ways to combat lithium battery fires.

 

On industrial scale lithium back up battery rooms they now use "gas analysers".  The batteries start giving off certain gasses in the days and weeks leading up to "failure".  By constantly monitoring the room and the gasses they can now accurately determine if some cells are about to "fail".  This technology is VERY expensive, and currently only used in the google type data centres.

 

 

Back at home, for the ordinary e-bike battery .... NO way to measure emminant failure .....

Good points and I know on generation projects were we have had fuel gas, electricity and lubricating oil the replacement detectors were the appropriate Honeywells linked to the SCADA. Not a cheap exercise but worth it for big installations.

[Hairy]

A friend sent me this setup he just had installed yesterday ......... I have just taken him off the "friends list"

 

[HdB]

1 hour ago, Hairy said:

A friend sent me this setup he just had installed yesterday ......... I have just taken him off the "friends list"

 

Sheesh, that 8KW inverter looks rather big!
We (finally) got a quote for our system, going with the 5.5KW Sunsynk inverter. The bigger inverter would have meant cutting down on panels or battery initially, plus is likely overkill for our usage.

[TheoG]

33 minutes ago, HdB said:

Sheesh, that 8KW inverter looks rather big!
We (finally) got a quote for our system, going with the 5.5KW Sunsynk inverter. The bigger inverter would have meant cutting down on panels or battery initially, plus is likely overkill for our usage.

Agree with you on this, you can never have two much battery capacity and you need the panels to be able to charge them.

5.5kW inverter would be sufficient for more than most households.

[Hairy]

1 hour ago, HdB said:

Sheesh, that 8KW inverter looks rather big!
We (finally) got a quote for our system, going with the 5.5KW Sunsynk inverter. The bigger inverter would have meant cutting down on panels or battery initially, plus is likely overkill for our usage.

He intends building on to the system in the future.

 

[dave303e]

3 hours ago, HdB said:

Sheesh, that 8KW inverter looks rather big!
We (finally) got a quote for our system, going with the 5.5KW Sunsynk inverter. The bigger inverter would have meant cutting down on panels or battery initially, plus is likely overkill for our usage.

We have the same one, it is a great inverter. 8kw might seem a lot, and yes it probably is, but it allows for a bit more expansion than the 5,5kw would further down the line which is crucial for us off grid...

[lechatnoir]

9 minutes ago, dave303e said:

We have the same one, it is a great inverter. 8kw might seem a lot, and yes it probably is, but it allows for a bit more expansion than the 5,5kw would further down the line which is crucial for us off grid...

yeah, off grid with an electric oven and geyser, you'll need 8kW min... my geyser was mislabelled on the DB and put on the 5kw inverter and when I turned on my shop vac I got my own personal loadshedding as the geyser thermostat kicked in and tripped the inverter. I now know to work around the geyser which is on a timer and I'm practically off grid, except for my oven...

my 5kw Sunsync was faulty out the box and as a stopgap, my installer put in an 8kW he had kicking around (wtf??) and it was HUGE! had to reorganise my wood store as it took up way more space

[dave303e]

3 minutes ago, lechatnoir said:

yeah, off grid with an electric oven and geyser, you'll need 8kW min... my geyser was mislabelled on the DB and put on the 5kw inverter and when I turned on my shop vac I got my own personal loadshedding as the geyser thermostat kicked in and tripped the inverter. I now know to work around the geyser which is on a timer and I'm practically off grid, except for my oven...

my 5kw Sunsync was faulty out the box and as a stopgap, my installer put in an 8kW he had kicking around (wtf??) and it was HUGE! had to reorganise my wood store as it took up way more space

ya, with 8kw you don't get so close to maxing it out which is also reassuring not sitting thinking what else is on when you hit an appliance or tool. We have gas geysers and a gas oven for cooking dinner. But the mrs has a big electric oven for baking so she can bake in the afternoons no issues at all. It also runs all my tools happily except the welder.

[Pure Savage]

Last day of the shedding! Installer came yesterday to check out the install site. I need to install a batton for him and some thermal insulation on the vibracrete and we ready to rock and roll.

 

[Schnavel]

47 minutes ago, lechatnoir said:

yeah, off grid with an electric oven and geyser, you'll need 8kW min... my geyser was mislabelled on the DB and put on the 5kw inverter and when I turned on my shop vac I got my own personal loadshedding as the geyser thermostat kicked in and tripped the inverter. I now know to work around the geyser which is on a timer and I'm practically off grid, except for my oven...

my 5kw Sunsync was faulty out the box and as a stopgap, my installer put in an 8kW he had kicking around (wtf??) and it was HUGE! had to reorganise my wood store as it took up way more space

Exactly - I'm practically off-grid with my 8kW, and I run 2 electric geysers during the day, as well as my electric oven (gas stove top).

I do have 14.2kWh of battery storage and 7.7kW of panels on the roof, which helps a lot!

[-cK-]

53 minutes ago, lechatnoir said:

yeah, off grid with an electric oven and geyser, you'll need 8kW min... my geyser was mislabelled on the DB and put on the 5kw inverter and when I turned on my shop vac I got my own personal loadshedding as the geyser thermostat kicked in and tripped the inverter. I now know to work around the geyser which is on a timer and I'm practically off grid, except for my oven...

my 5kw Sunsync was faulty out the box and as a stopgap, my installer put in an 8kW he had kicking around (wtf??) and it was HUGE! had to reorganise my wood store as it took up way more space

Yes a 8kW would have been nice and give some margin to play with but if you know the limitations of the 5.5kW and work just a little bit smart it can do the job.  One thing I just did is I just dropped the element in my geyser down to 2000w (was 3000w) runs just a little longer but it is now within the spec of my current 2.7kw panels setup.  So unless it is cloudy outside I use no battery or grid for it anymore and it gives me an additional 1kW to play with once my extra panels will get added so then I can actually have the geyser on with something else as well.

[LazyTrailRider]

2 hours ago, TheoG said:

5.5kW inverter would be sufficient for more than most households.

Every once in a while, mine uses its 6-8kW burst capacity.

With these systems, the devil is in the outliers. Outliers in terms of successive rainy days, outliers in terms of local outages which prevent charging for longer than loadshedding slots, outliers in terms of unexpected usage by people who aren't aware of the limitations.

My system goes over 6kW several times a month. All that needs to happen is for these appliances to be switched on at the same time by different people while the geyser (2kW) is already on: Washing machine, dishwasher, kettle, leafblower.

Yes, a system sized "just large enough" will be fine 90% of the time, but it's the 10% that gets you.

 

[TheoG]

19 minutes ago, LazyTrailRider said:

Every once in a while, mine uses its 6-8kW burst capacity.

With these systems, the devil is in the outliers. Outliers in terms of successive rainy days, outliers in terms of local outages which prevent charging for longer than loadshedding slots, outliers in terms of unexpected usage by people who aren't aware of the limitations.

My system goes over 6kW several times a month. All that needs to happen is for these appliances to be switched on at the same time by different people while the geyser (2kW) is already on: Washing machine, dishwasher, kettle, leafblower.

Yes, a system sized "just large enough" will be fine 90% of the time, but it's the 10% that gets you.

 

I hear you, its a constant effort to educate the ladies in the house that even though we spent a lot on our system, that does not mean we can turn on everything at the same time.

Luckily my geyser is running independently on its own PV & MPPT controller, so at least that is not an additional load on the inverter.

We hardly ever pull more than 4kW from the inverter, but that is only because I watch & monitor the usage like a hawk .... 🤦‍♂️🙈

Edit:  Bad sun days is the worst, especially a few in a row.  This requires careful planning to keep things going.  And then also in our area the infrastructure is k@k to say the least, we had multiple longer than 24 hour outages in the past.

Edited January 26, 2023 by TheoG

[Pure Savage]

12 minutes ago, TheoG said:

I hear you, its a constant effort to educate the ladies in the house that even though we spent a lot on our system, that does not mean we can turn on everything at the same time.

Luckily my geyser is running independently on its own PV & MPPT controller, so at least that is not an additional load on the inverter.

We hardly ever pull more than 4kW from the inverter, but that is only because I watch & monitor the usage like a hawk .... 🤦‍♂️🙈

Edit:  Bad sun days is the worst, especially a few in a row.  This requires careful planning to keep things going.  And then also in our area the infrastructure is k@k to say the least, we had multiple longer than 24 hour outages in the past.

Interesting, so once your batteries are full, you can use in my case the 3kwh of solar on base load plus whatever else you use, then another 2kw will pull from battery, then anything above that it can switch over to eskom if Eskom is there?

Have found with this process the devil is in the detail - like the pump for the solar geyser is 12v with its only little panel - cute. But the geyser wise is on the geyser breaker, so when load shedding the pump stops and does not circulate and is not as efficient. 

Thinking of running a separate cable from a plug circuit to power the geyser wise, so the 12v pump can work during load shedding.

[TheoG]

Just now, Pure Savage said:

Interesting, so once your batteries are full, you can use in my case the 3kwh of solar on base load plus whatever else you use, then another 2kw will pull from battery, then anything above that it can switch over to eskom if Eskom is there?

Have found with this process the devil is in the detail - like the pump for the solar geyser is 12v with its only little panel - cute. But the geyser wise is on the geyser breaker, so when load shedding the pump stops and does not circulate and is not as efficient. 

Thinking of running a separate cable from a plug circuit to power the geyser wise, so the 12v pump can work during load shedding.

That's why I like my system much more, there is a dual element in the geyser (take power from 2 PV panels or Eskom).  So the geyser is heated by PV electrical power and not pump water through vacuum tubes or similar.

Install is also a lot simpler, zero plumbing required.

[Trashy]

If anyone is upgrading, I'm looking for a 3kw, 24v inverter.

Would prefer to buy from a reputable Hubber rather than brave the wilds of marketplace and scamtree.