I’m not aware of any G98 application that has had an export limit imposed, other than the 3.68kW limit, although given the grid’s inability to cope in some cases, it might be a good idea. A big part of the problem is when people install solar without batteries, so that the grid is regularly overloaded on sunny days. So yes, a G98 may be a bit more than a “rubber stamping exercise” but not much more, as anyone can get one with virtually no chance of it being rejected.
Yes if you are restricted under a G98 to less than 3.68kW you can, I understand, ask for the justifications or even a reconsideration of the restriction perhaps at a later time.
I have not heard of a G98 application getting rejected, unless perhaps not completed correctly - its simply the G98 conditions are stated on it - ie any export limit upto and including 3.68kW.
According to my son-in-law who runs businesses in this area such restrictions are not common, but do come up from time to time.. and is I suspect more to do with local utility conditions.
I’d imagine with more and more new houses coming with Solar Panels (albeit not many), a G100 for a large installation may be more likely in the future. Having an EV with regular usage may be more suitable here, ensuring you get to use all you generate.
I have G100 authorisation and there is no dynamic control, just a fixed limit.
I am aware of these protocols. I’ll copy here an extract of my DNO approval.
Thank you for providing the completed G99 Form A3-2 and a completed copy of the G100 export limitation scheme Installation and Commissioning Tests form following the installation and commissioning of small-generation equipment at my address.
Thanks, what that is telling you with the associated response that you will have had is your export maximum from your inverter listed in your G99, probably stated by your installer is conditional on having the G100 ELS enabled on your inverter so as not to unbalance the local grid under certain conditions. Ie you are generating more than you are using such that you would otherwise breach your export limit.
My G99 permit back from the DNO states my permissions:
“
Agreed export capacity (including G100 devices): 5.00 kW
G100 export limiting scheme on premises? No
“
So I have been permitted to export upto 5.00kW without requiring the adoption of G100.
I suspect if at some point I upgrade my system and export upto say 8kW on a single phase, I might need to activate G100 as a condition of connection when I submit a new G99.
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I was talking to someone today who processes these applications for a living, and he warned that if solar installations proliferate in your vicinity, a G100 could allow your DNO to throttle your export far more than you might want, so he advised that it’s best to get the highest G99 you can, and get it fast. If you don’t go through with it, there’s every possibility that a future G99 application would be more limited, or even refused as more and more installations overwelm the grid.
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My Tesla Powerwall 3 has been software configured with an export limit of 6 kW according to the DNO’s approval under G99 (as I understand it). I believe that the Powerwall 3 is G100 compliant and this allows the export limit to be configured as a software only setting.
The hybrid inverter itself is capable of delivering 11.04 kW from Solar and/or the battery, hence the need for there to be a way to limit it. This capability can be used to its maximum for house loads though, and I have seen several occasions where the house load has exceeded 6 kW, albeit only for a short while.
The 6 kW export limit was configured upon installation and cannot be changed except by submitting a request to Tesla through my installer (with associated DNO approval paperwork I presume). The DNO have no means to interact with the system, dynamically or otherwise.
With rising fuel prices I have now ordered a new solar panel system with Sigenergy inverter and battery. 5.6kw system with 12 panels at 465 watts each. I have an EV car and looking to go EV van when my lease expires in 12 months.
Have benefitted from EV discounts with VW OVO 10000 miles a year free and discounted charging rate.
Lookimg forward to the new Solar system. It should in effect mean free electricity with system, batteries and EV deal. Figures show 85% of my electricity will be free. And then cash back from grid!
The Sigenergy is AI based and has all the bells and whistles. Looking forward to it. I have done this as it has become a necessity in current fuel crisis.
The benefits of an EV are cost has meant I am not paying anything for fuel with 10000 miles a year free for 3 years! OVO will be depositing £420 into my account this August.
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Although relatively new to market, I believe the Sigenergy system is a good one and very flexible to configure and expand if needed. For me the only fly in the ointment is that it regularly phones home to China.
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The other option was Fox, also Chinese. The Sigenergy offers more in terms of the future and does everything itself, maximising the system effortlessly.
Very happy with our Sigenergy system, not been brave enough to go AI yet…….i just dump our excess from the battery leaving enough to get us through to midnight when it recharges at EV rate. We have a 10 kw inverter, and are able to export at 10kw.
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My 500DR system uses alot of energy and is left on 24/7. And EV car uses a fair bit. So for me looking at the figures I will get my money back in 5 years. Got the deal on 0% finance 2 years and 0% VAT!
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I understand that Fox systems tend to be made up of many parts which can look untidy if that matters to you. The only other option in the same league is Tesla if you don’t have a negative bias 
.
I have a small 3KW solar system with a G98. This just about generates what we use taken over a year - we don’t have a battery. Our bills are very low and we are happy with what we have.
Looking ahead I am intrigued by plug in/balcony solar which is supposed to be coming very soon. This would be linked to an ASHP and/or EV, using the EV as a battery. Would only having a G98 be a problem - leaving aside not being able to sell the surplus >3KW? I’m wondering whether any surplus would be earthed away somehow or would the grid just take it and not pay?
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Go on, do it!
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Deal is done. Signed and sealed, deposit paid. Fox system had slightly bigger battery. But Sigenergy has more for the money in terms of ease of use. Both are excellent, but this is relatively new territory for me.
I have had solar panels and inverter system in a previous life with ex wife. We got alot of money back and electricity was cheap with 4kw system.
So this will be 2nd time round for me!
With 0% finance as long as the overall price was fair it all sounds like a good deal.
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Depending on what you are trying to do……we wanted power cut resilience and the ability to run the house 365 days on the EV rate. We ordered 18 kw battery, but realised in winter it would not be enough, so now have 27kw. That sounds a lot but if you conserve the battery by not fully charging, and leave say 20 % as reserve for a powercut…..it dwindles. But of course you could do 0 to 100% every time, each to their own.
Hope you enjoy the journey 2nd time round
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I compared other companies and this was cheapest and through OVO. I am tied in with EV wirh free charging but have got great deals.
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