MSE guide: plug-in solar panels

MSE_Andrew

Hi everyone,

We've just published a new guide on Plug-in solar panels and we'd love to hear your feedback.

If you haven’t already, join the forum to reply.

Thanks for your help,

MSE Andrew

subjecttocontract

I guess some people with a rooftop solar panel installation will buy & install the plug ins. The article doesn't cover the situation for them if they are already exporting excess energy to the grid, or if this might overload the system in some way or other qustions.

QrizB

Hi @MSE_Andrew the article currently says "Updated 23 April 2026".

There have been a lot of changes in the past three-and-a-half months. Has it been revised since then?

RobfromCornwall

“Some kits should also come with will also come with mounting equipment too.”

This needs editing.

“Plug-in solar could cover around a quarter of your homes electricity use”

Apostrophe missing.

“a typical 4.6kWp system costs about £7,600 to install”

Should that be kWh?

debitcardmayhem

https://forums.moneysavingexpert.com/discussion/comment/82105685#Comment_82105685

NO it is correct kWp = peak

MSE_Chris

https://forums.moneysavingexpert.com/discussion/comment/82105634#Comment_82105634

Hi there,

For some reason it was showing the date the guide was created, not when it was last updated.

I've now fixed that!

paul991

how will it work if you already have solar but just want to add a couple of panels in a different direction to get the early sun. Do I need to need to inform DNO as Im unlikely to ever export any more.

NedS

https://forums.moneysavingexpert.com/discussion/comment/82105863#Comment_82105863

That depends, you may need to gain approval before connecting it.

If your combined inverter ratings are now over 3.68kW then you will need to apply for permission to connect (G99) the new device and gain approval from the DNO before plugging it in.

If you previously had G98 approval for an inverter 3.68kW or smaller, and the new combined inverter ratings still remain below 3.68kW (seems unlikely as the original inverter would have to be 2.88kW or smaller), then you would simply need to notify the DNO of the new installation via a G98 Part B form for plug in solar which should be included with the inverter when you purchase it, assuming it has been approved for plug in use.

What rating is your current inverter?

subjecttocontract

Whats the penalty for not gaining approval ?

Alnat1

AI cannot find any sources showing where someone has faced penalties for not gaining G99 DNO approval

Officer_Dibble

The article compares (unfairly) the claimed unrealistic savings figures for plug in solar with real world savings for rooftop PV. To get anywhere near the claimed savings you'd have to use every kWh generated at the time it was generated. The only way you could do this without being in all the time would be charging a car, but if you have an EV at home you'll be on a smart tariff or E7 with cheap night time charging. Beyond heating a tank of water or running AC most of the electricity generated is going to go on low daytime general consumption or just go straight to the grid.