I think BG was 3p if you are with another supplier, but want to export to them? So when our new tariff kicks in at the end if the month we will import at 9p, but export at 15.1 p. I can live with that.
I was surprised at the size of the panels when you are up close to them on the ground, when i visually looked at my roof and guessed the number of panels……i was way off.
Glad its going to plan.
It seems understandable to me that they have reduced export rates, as they are obliged to pay you for power that nobody wants, i.e. from generation during periods of low demand which is causing significant instability on the grid. I don’t know what the relationship is between retailers (Octopus) and DNOs in this respect, as it’s the DNOs and National Grid who are struggling, but I assume there must be some market forces driven by this issue.
TOU tariffs, on the other hand, along with load shifting, are part of the solution, so it makes no sense that they are unavailable, just as we move into summer, when problems caused by overloading the grid with solar generation are at their worst.
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And yet, when I spoke to Octopus yesterday, they said that Economy 7, EV and heat pump tariffs were all available, albeit at fixed prices only. I suspect that’s the confusion, with your screenshot referencing the (closed) flexible tariff.
it doesn’t fully add up to me - there would be no new commercial solar farms created if that was generally the case as there would be no demand - but they are popping up like mushrooms. Yes they have limited batteries too to help provide consistency with temporary cloud cover and fading light - just like you can do with a domestic panel and batteries.
It was I understand according to Greg Jackson equally about the added charges that are applied onto imported power and not exported power that drove in part the differential… however a whole load of those charges have been removed as of 1 April (green levy charges) by HMG so that would imply the differential should now be narrower - not wider.
So I understand needing to drive profitability and increased financial cushions in times of volatility - but I just ask for more transparency rather than ‘crisis washing’
It will be exciting when the first solar starts replacing electricity from the grid.
On Friday a third battery gets fitted here. Not likely to pay for itself but it will help with winter heating via the ASHP. We can keep more reserve for grid outages which at present are infrequent. I can’t but think that the grid will get worse with the lack of investment to build one that deals properly with renewable energy.
Phil
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Yes, but a solar farm would require an assessment of, and where required an upgrade to the grid to ensure that it could cope. Rooftop solar requires little or no such assessment, and in many cases can be installed without prior notification to, or consent of the DNO. So local residential grid infrastructure has supply forced onto it regardless of whether or not it can cope. Batteries can absorb this oversupply, but there is no obligation on homeowners to add batteries. It will take many years for the grid to upgrade every residential supply that needs it to a point where it can cope with every house that chooses to add rooftop solar.
The DNO have had plenty of warning about solar. Solar PV was being fitted long before the FIT incentive scheme which started in 2010, so they have had time enough to get a plan together, if they have one. I am fortunate that i got the 10 kw i asked for.
I am limited to 6kW export. I’m in a rural location so that might account for it. Also my PV array is only 6.825 kW, so maybe they (Northern Powergrid) based it on that.
Due to this limit, tariffs like Octopus Flux and Intelligent Flux are less useful as in the 3 hour peak rate export period I am limited to 18 kWh of export. My best sunny day last year produced 44 kWh, so I’d struggle to consume the rest or store it all. Given we now have an EV, IOG is the best option.
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They have had warning insofar as they knew what was coming, but as businesses they gave little or no interest in costly grid upgrades without government initiatives and funding which have not been forthcoming. Plenty of homes will have caps of 3.6kW imposed which is the minimum that DNOs cannot refuse.
Domestic solar does indeed have a survey and often detailed assessment undertaken if you wish to export… this is your G declaration which permits what and how you can export, typically becoming more specific if you export more than a relatively trivial amount of 3.68 kW of the G98
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Unfortunately not quite, there are some locations where you are not permitted to export at all by your DNO at anytime… not that common but do exist.
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Gazza it’s more about balance rather than total infrastructure.. though in the limit infrastructure is clearly important .. it’s the balance that is key.
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That’s correct, but my point is that there are large numbers of G98 installations in the UK, and these require no prior approval from the DNO. The application is made to, and approved by the DNO after installation, so they never reject them.
Really? I believe the G98 is approved and issued by your DNO, your installer will typically make the application using the details of the size and potential power output of your system, and the installer will configure any limitations imposed by the DNO - and for G98 its 3.68kW or less.
On the final day of installation after commissioning i got emailed my G99 approval and MCS certificate from my installer, so mine must have been pre-approved? I was then able to apply for SEG export with those details.
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Yes, a G98 is submitted after installation, unlike a G99, so it’s just a formality. Rejection by the DNO would be after the system has been commissioned and paid for, and rejections are very rare.
- G98<</ (Microgeneration): Designed for standard residential PV or small battery systems (< 3.68 kW single-phase or < 11.04 kW three-phase). It implies the equipment is “type-tested,” allowing installation followed by notifying the Distribution Network Operator (DNO) within 28 days.
- G99<</ (Larger Scale): Necessary for any system exceeding G98 limits. This requires a formal application process. The DNO must approve the connection before installation to prevent local grid overloading.
- G100<</ (Export Limitation): G100 is not a size classification but a technical standard for devices that actively restrict the amount of energy sent back to the grid. It allows installers to install a larger inverter (e.g., 6 kW) but set a software/hardware limit (e.g., capping it to export only 3.68 kW) potentially avoiding costly grid upgrades required under G99.
We initially had a G98, as our solar was installed a week after ordering and the G98 process is really quick. It soon became apparent that the restriction was holding our output back on sunny days, so I applied for a G99 myself, to allow the fully 6kW output. It was a bit confusing because it wasn’t a standard new application, but a modification of an existing installation. Southern Electric were brilliant, helping me with the forms, which are quite complicated. Once it was approved, I switched off the inverter, moved a couple of dip switches, turned it on again, and hey presto. I was quite pleased with myself at the time! Our 16 panels rarely produce more than 6kW and with DC to AC conversion losses very little gets wasted.
My G99 application was submitted once the installation nearing completion with the evidence of the commissioned system of the stated requirements. We bypassed a G98. My installer sent me the agreed DNO G99 and MCS certificate within a couple of days. It was this info I used to send to the utility company to be paid for export. That took about 10 days to turn around.
This G99 confirmed any limitations and was the authorisation to allow us to sell exported power.
A G98 can limit your export to be less than 3.68kW or even limit it altogether. It is certainly not a rubber stamping exercise! But generally you are either not permitted to export at all or you are permitted upto 3.68kW under a G98 but is quite a blunt tool.
I understand more often today if power export level is sensitive a G100 limit is imposed by the DNO to allow export where your local grid can support it. But you need to use G100 certified equipment where your inverter level is greater than your permitted export, and you are not using the all the generated electricity.