Plug in solar

QrizB

But if two (or more) inverters are providing each other with the required external reference

That bit isn't possible with a consumer grid-tied inverter.

If you want to know the exact way the electronics sense it, you're going to have to read a reference book.

matelodave

You probably have to ask the equipment supplier how it works as I guess that there should be safeguards to prevent that sort of thing happening.

Otherwise all sorts of stuff could end up going a bit awry, like trying to feed half the street if the inverters dont all shut down at the same time as the mains power is lost. The rules might specify that you can only have one unit at a time but rules can and will be broken so you cant rely on them to protect people from doing something wrong or stupid.

Qyburn

https://forums.moneysavingexpert.com/discussion/comment/81939589#Comment_81939589

With no reference, just following each other's waveforms then I expect the frequency to drift and at some point that will exceed expected limits and the inverters will (should) shut down. Same may apply to voltage.

But it's an interesting scenario that would apply in the case of a power cut, even if the plug in systems are in different houses on the same LV phase.

Scot_39

https://forums.moneysavingexpert.com/discussion/comment/81938847#Comment_81938847

None of which will happen without consulting domestic regulators that what they are doing is safe.

And thats safe for all potential households - from analogue meters to smart, from ancient fuseboxes, to modern protected consumer units.

NedS

https://forums.moneysavingexpert.com/discussion/comment/81939171#Comment_81939171

I don't foresee that happening as these low output systems (<800W) are primarily designed to cover background load only, not for export although obviously they are capable of exporting any excess generation.

The government will already have to update the electrical wiring regulations and G98 regulations. Most suppliers require an MCS certification to export, which obviously these plug-in systems will not have.

tfhnota

As an ultra low user, no export payment - necessary to get the summer excess back during winter - then it would be a no from me, I will continue with getting the bits for an off-grid circuit, although people are already buying the cheaper panels in preparation, judging by the out of stock at the usual vendors that offer free delivery for low quantities. Various factors indicate solar panel price increases over the next six months, although the big installers will have already bulk-purchased enough panels not to need any increases, other than ramping up their greed.

Reed_Richards

My fixed solar PV system has a current sensor that clamps around the feed wire from the mains so it can sense import and export, and potentially limit export. A plug-in solar system won't be able to sense any export and so any excess of power generated over power being used in the home will be exported.

tfhnota

there are types of plug-in solar that integrate a battery, saving the power for when needed rather than exporting, though the cost soon adds up if you want some serious kwh of battery

NedS

https://forums.moneysavingexpert.com/discussion/comment/81942204#Comment_81942204

But if you are a very low user, then some of those 2-3kWh systems may be ideal for you, allowing you to store sufficient excess solar during the day to power your home overnight. An 800Wp system is capable of producing 4-5kWh this time of year.

Qyburn

https://forums.moneysavingexpert.com/discussion/comment/81942204#Comment_81942204

Do they have some ort of monitoring at the incoming supply connection? I can't see how a purely "plug in" system would know how to manage the battery without.