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Solar Panels UK - is it worth it?

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I know some of you are exporting from your Powerwalls during Octopus Saving Sessions, but is anyone regularly exporting excess battery just before the next off-peak period? Any potential risks or pitfalls in doing this such as maybe invalidating Tesla warranty or Octopus not being happy with it not being direct from solar?
I will from spring onwards. At the moment I prefer to keep the available energy to run the house (the ASHPs do use a fair bit more energy in the winter).
I guess the drawback is the increased wear on the batteries with more charge cycles, but hey....
 
I know some of you are exporting from your Powerwalls during Octopus Saving Sessions, but is anyone regularly exporting excess battery just before the next off-peak period? Any potential risks or pitfalls in doing this such as maybe invalidating Tesla warranty or Octopus not being happy with it not being direct from solar?

It's just proof of concept for the octopus sessions and Im sure they are aware. Beyond that, if you think you are doing something wrong, you probably are and it's your conscience and risk of it going wrong.

At 13.5 kW capacity it's a bit of a sweet spot for the average house. You would need 2 powerwalls to be doing such things daily and the ROI just for that purpose would be a bit silly imho.

Much better off getting extra solar and export if you can for that purpose as its cheaper, again imho
 
I will from spring onwards. At the moment I prefer to keep the available energy to run the house (the ASHPs do use a fair bit more energy in the winter).
I guess the drawback is the increased wear on the batteries with more charge cycles, but hey....
Still on gas heating here and I usually have some charge left in the battery by 23:30.

The Tesla warranty says unlimited cycles for “Solar self consumption/backup only” but for “Any other application or combination of applications” it limits it to “37.8MWh of aggregate throughput”.

I’m assuming exporting from the battery will come under the latter.
 
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It's just proof of concept for the octopus sessions and Im sure they are aware. Beyond that, if you think you are doing something wrong, you probably are and it's your conscience and risk of it going wrong.

At 13.5 kW capacity it's a bit of a sweet spot for the average house. You would need 2 powerwalls to be doing such things daily and the ROI just for that purpose would be a bit silly imho.

Much better off getting extra solar and export if you can for that purpose as its cheaper, again imho
I don’t necessarily think it’s wrong, after all if Tesla or Octopus don’t care, why wouldn’t I take advantage. I definitely don’t want to break any T&Cs though, hence asking.

I don’t always use the full 13.5 kWh in a peak period day. I ran the numbers on a second Powerwall but it didn’t stack up. I have the maximum number of solar panels I can get away with.

I use Home Assistant so the automation wouldn’t be difficult.
 
I don’t necessarily think it’s wrong, after all if Tesla or Octopus don’t care, why wouldn’t I take advantage. I definitely don’t want to break any T&Cs though, hence asking.

I don’t always use the full 13.5 kWh in a peak period day. I ran the numbers on a second Powerwall but it didn’t stack up. I have the maximum number of solar panels I can get away with.

I use Home Assistant so the automation wouldn’t be difficult.

People like me in glass houses dont throw stones... People ask me all the time where do I get my money from.... You guys do whatever you want ;)
 
Interestingly Octopus say…

“Outgoing Octopus is perfect for homes with solar panels, battery storage, or any other way of sharing energy back to the grid.”


And also…

“That might be energy generated by your solar panels, a micro-wind turbine or even energy you’ve stored in a home battery or an electric vehicle capable of discharging to the home.”


(My highlighting).
 
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Here’s the definitive answer…

“YOU CAN: ….. charge up home batteries when energy’s cheapest to feed back into the grid later”

IMG_0616.jpeg


 
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Here’s the definitive answer…

“YOU CAN: get a micro-wind turbine installed, charge up home batteries when energy’s cheapest to feed back into the grid later”

I fixed that for you ;)

is anyone regularly exporting excess battery just before the next off-peak period?

Your suggestion here is that you want to charge off peak and discharge off peak and then what?... charge off peak again so that you have cheap electric for the peak time again?


The whole idea of them giving you a high export rate is to give you an incentive to not use your renewables (such as solar, wind turbine or hydro) and sell it to them.

Think of IOG... if you have solar and plug in during the day and get off peak slots when the sun is shining on them, charging your car then if of absolutely no use to you for financial gain, it actually loses you money since you are consuming at 7.5p but this also cancels your solar export at 15p.

Your battery makes more financial sense for self consumption OR grid balance which is why the rates are what they are. A better idea to use that "extra" power from the battery is finding something else to use it on such as an induction hob or even just boil the kettle instead of putting cold water on the gas hob.

TL'DR: IOG is not a wind turbine ;)
 
I fixed that for you ;)



Your suggestion here is that you want to charge off peak and discharge off peak and then what?... charge off peak again so that you have cheap electric for the peak time again?


The whole idea of them giving you a high export rate is to give you an incentive to not use your renewables (such as solar, wind turbine or hydro) and sell it to them.

Think of IOG... if you have solar and plug in during the day and get off peak slots when the sun is shining on them, charging your car then if of absolutely no use to you for financial gain, it actually loses you money since you are consuming at 7.5p but this also cancels your solar export at 15p.

Your battery makes more financial sense for self consumption OR grid balance which is why the rates are what they are. A better idea to use that "extra" power from the battery is finding something else to use it on such as an induction hob or even just boil the kettle instead of putting cold water on the gas hob.

TL'DR: IOG is not a wind turbine ;)
Fixed what? I think you’ve mis-read it. Look at the screenshot I posted. The octopus statement is an “OR” statement with 3 options. It’s micro wind turbine OR buy/sell using a house battery OR use a V2H vehicle.

Maybe you missed it because there is a comma after the wind turbine bit rather than another OR but it basically reads like this…

“YOU CAN: get a micro-wind turbine installed [OR] charge up home batteries when energy’s cheapest to feed back into the grid later, or (if you’ve managed to get your hands on a vehicle-to-grid charger) use your electric car’s spare battery.”

I charge the house battery overnight to 100% during the off peak rate. My solar is all exported during the day. The house is powered from the battery during the peak period. By about 10:30/11pm I sometimes still have some charge left in the battery so can export that excess during the peak period. Come 23:30 rinse and repeat.

I am doing exactly what Octopus say is allowed… “YOU CAN: … charge up home batteries when energy’s cheapest to feed back into the grid later”

I don’t see the issue?

I don’t want to put less than 100% in the battery overnight because sometimes we need nearly all of it. Or in case of a power cut I want as much left as possible. If sometimes that means I have a few kWh left at the end of the day why wouldn’t I want to sell it back to Octopus at a profit when they clearly say that is something we can do?
 
If I want to build an RTG in the comfort of my own home, I don't see why Octopus should get in my business. It's great for space heating, and the kids find their extra fingers really useful!

On a more boring note, check Export Tariffs - Terms & Conditions
"4.5.1 We are not obligated to make Export Tariff payments to you:

(i) for any ‘Brown Export’ – i.e. exported electricity not generated by an eligible generation asset, (including standby generators, batteries and technologies not supported by the Smart Export Guarantee;"

So their FAQ contradicts their terms and conditions
 
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I know some of you are exporting from your Powerwalls during Octopus Saving Sessions, but is anyone regularly exporting excess battery just before the next off-peak period? Any potential risks or pitfalls in doing this such as maybe invalidating Tesla warranty or Octopus not being happy with it not being direct from solar?
Raises hand. Solar has picked up a smidge now, so more days where PW is a bit more likely to have surplus charge by late evening. No point letting it go to waste, so I switch PW's Energy Exports setting to "Everything" at around 9-10pm to earn a few more pennies. PW does a decent job of adjusting export power in order to hit the standby reserve exactly on 11:30pm.

I don't see anything in Octopus' Ts+Cs to suggest this is against their rules.
 
On a more boring note, check Export Tariffs - Terms & Conditions
"4.5.1 We are not obligated to make Export Tariff payments to you:

(i) for any ‘Brown Export’ – i.e. exported electricity not generated by an eligible generation asset, (including standby generators, batteries and technologies not supported by the Smart Export Guarantee;"

So their FAQ contradicts their terms and conditions
Yes very contradictory. The people writing these documents obviously don’t talk to each other.

The T&Cs probably hold more weight though if they really didn’t want to pay out.
 
Yes very contradictory. The people writing these documents obviously don’t talk to each other.

The T&Cs probably hold more weight though if they really didn’t want to pay out.
Less than you might think in a regulated market. They're obliged to be fair to customers, and if you say clearly that export is payable in the FAQ, it would be unfair to have terms override that.
Odds are they'd lose if it went to OFGEM.
 
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Solar has picked up a smidge now, so more days where PW is a bit more likely to have surplus charge by late evening. No point letting it go to waste, so I switch PW's Energy Exports setting to "Everything" at around 9-10pm to earn a few more pennies. PW does a decent job of adjusting export power in order to hit the standby reserve exactly on 11:30pm.

its not going to waste if you are selling your solar a a higher price than what you charged the battery from the grid though is it? :)