Solar... who's clued in?

indica

Serial flasher
Just sounds like a good way to keep you clamped to the tit of the power companies to me.
No, it's so if there is a line down you are not pushing power into the grid and the ETSA/ Ergon whoever doesn't get zapped.
 

Jpez

Down on the left!
No, it's so if there is a line down you are not pushing power into the grid and the ETSA/ Ergon whoever doesn't get zapped.
Yeah I get that. But I’m sure with the smart systems these days they could make it so supply outbound from the property is stopped in that event or isolated. Something along those lines.
In saying that I know nothing about how solar or electrical distribution works. Just seems very convenient for the power companies is all.
 

indica

Serial flasher
But I’m sure with the smart systems these days they could make it so supply outbound from the property is stopped in that event or isolated. Something along those lines.
They can but everything costs more
 

Fred Nurk

No custom title here
That's what I thought. It's a shame you can't isolate your house from the grid in instances like this.
You can...

You need to have a 3 way switch installed to isolate mains infeed. I do it with my generator. The generator is isolated unless the switch is flipped then only the house (two circuits as it is wired 3ph) are energised, fridge, freezer, water pump, hot water trigger, biocycle, TV, stereo etc. No back emf into the grid but set up has to be inspected and approved, here anyway. I don't wake up the solar though, the demand can't handle the supply and one or other sources could release the magic smoke. Maybe. Not worth the risk. Potentially hard on consumers in the house if solar is up and down with cloud cover. I am assuming the solar inverter can just ramp down to meet demand, not sure what happens when demand > than supply... my house generator is 3.5kVA and solar is 3.5kW.

Biggest issue is knowing when power is back as neighbours are not close.
Its definitely possible to be able to isolate your house and keep running. Its not possible with just a solar inverter and nothing else, as mentioned elsewhere, all grid connected inverters must shut down when islanded (i.e. the grid disappears).
Systems that can generally have a means of automatically disconnecting the house from the network when the grid disappears AND a battery inverter system that provides the equivalent of the grid to your house.
Not all solar / battery inverter systems can be configured to do so (enphase is one that can't) and you can't run your little home generator alongside the solar when disconnected from the grid either, unless you have a specific system that allows you to (such as an Outback Power unit).

Grid connect solar inverters don't ramp down for external reasons, so if you run them in parallel with the generator they will happily feed power into your generator until it shits itself.
 

Dales Cannon

lightbrain about 4pm
Staff member
Its definitely possible to be able to isolate your house and keep running. Its not possible with just a solar inverter and nothing else, as mentioned elsewhere, all grid connected inverters must shut down when islanded (i.e. the grid disappears).
Systems that can generally have a means of automatically disconnecting the house from the network when the grid disappears AND a battery inverter system that provides the equivalent of the grid to your house.
Not all solar / battery inverter systems can be configured to do so (enphase is one that can't) and you can't run your little home generator alongside the solar when disconnected from the grid either, unless you have a specific system that allows you to (such as an Outback Power unit).

Grid connect solar inverters don't ramp down for external reasons, so if you run them in parallel with the generator they will happily feed power into your generator until it shits itself.
That is what I thought. Generator works at night too.
 

Minlak

custom titis
We are interested in going Solar but I am really only interested if I add the battery pack so can store energy to use when its not generating. Cost would take a bit longer to recoup and I would want to double check I can use it if power goes out etc as well.
 

indica

Serial flasher
Yeah that is what I thought - Now we are home more during the day it is making more sense
Redearth do it, no idea of cost though as they don't have prices.
I've just had 16.5 kW of panels installed on a new build with a generator changeover switch for blackouts. No battery as yet as I don't think it is worthwhile.
 

Minlak

custom titis
Redearth do it, no idea of cost though as they don't have prices.
I've just had 16.5 kW of panels installed on a new build with a generator changeover switch for blackouts. No battery as yet as I don't think it is worthwhile.
If I was to build a new house right now I would have stand alone solar with a battery pack in the loan amount. Over a 30yr loan its nothing to be set up from the get go
 

Fred Nurk

No custom title here
We are interested in going Solar but I am really only interested if I add the battery pack so can store energy to use when its not generating. Cost would take a bit longer to recoup and I would want to double check I can use it if power goes out etc as well.
Based on current numbers its still not worth it economically.
 

Minlak

custom titis
My Nephew actually works at the Gladstone coal fired power station - he was telling me the problem with renewable energy right now is storage options. you have to have a way of storing the energy to allow for ram up in demands on the grid and currently its just not viable and or possible. So whilst the renewable energy can be used to take the load off coal stations the coal ones are needed when demand increases and they stations are asked to ramp up.
 

Fred Nurk

No custom title here
My Nephew actually works at the Gladstone coal fired power station - he was telling me the problem with renewable energy right now is storage options. you have to have a way of storing the energy to allow for ram up in demands on the grid and currently its just not viable and or possible. So whilst the renewable energy can be used to take the load off coal stations the coal ones are needed when demand increases and they stations are asked to ramp up.
This is part of the argument around 'dispatchable power' and the means to be able to provide the output needed. Coal stations are not very good at fast response, gas turbines are much better at it, and so is stored hydro.

Also worth considering the changes in electricity tariffs, and the existence of off-peak and super off-peak tariffs. These have existed long before the levels of renewable energy in existence today, and one of the intents would have been to allow the power station to not have to ramp back so much in times of low demand, rather encourage usage via lower pricing.

It is much easier to control the output when the input is able to be controlled though.
 

Minlak

custom titis
This is part of the argument around 'dispatchable power' and the means to be able to provide the output needed. Coal stations are not very good at fast response, gas turbines are much better at it, and so is stored hydro.

Also worth considering the changes in electricity tariffs, and the existence of off-peak and super off-peak tariffs. These have existed long before the levels of renewable energy in existence today, and one of the intents would have been to allow the power station to not have to ramp back so much in times of low demand, rather encourage usage via lower pricing.

It is much easier to control the output when the input is able to be controlled though.
Yeah he mentioned about the response time - Seems the Gladstone one is pretty much the quickest to be able to respond but its still an issue
 
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