Grid tie with local grid-fail backup?

DIY
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Does Victron (including in partnership with any other suppliers) have a solution where:

We have:

  • Solar PV
  • Batteries

And require:

  • Grid-tie feed-in of surplus when available
  • Backup (local islanding) in a grid fail scenario.
  • Obviously meeting all UK regulations regarding the above

This is an educational question with long term planning in mind.
For me, the ability to function when the utility power fails is paramount and my first priority.
But if a solution exists, it would be nice to be able to feed in excess solar power back to the grid in the summer months.

Naturally, at the current FIT of around 7p/kWh, some calculations will be in order to see if the extra cost of the specialised setup ever has a viable ROI.

Which is mostly the purpose of this question - to understand if such a system exists in the Victron world and to look further into costs…

Many thanks folks :slight_smile:

2

Yes, with a multiplus 2

Only i dont know your local regulations, so
I suggest to contact a local victron dealer that can help with that and system design

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3

In order to receive a SEG payment you have to engage an MCS installer who can provide a MCS certificate or you will ONLY have the Octopus option and it will set you back ÂŁ250 for an application. If you want backup power, you also need a dedicated earth rod for TNCS systems and a quite a number of other things to consider such as noise levels, heat generated when continuously running for export etc.

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Thank you - this is relatively hypothetical at this stage, so I don’t have a specific installation - our current house is not well suited to PV panels.

But I am interested in playing with numbers as a factor when we eventually move house - that might factor in to the choice of location, house style (especially roof), local power reliability (if very rural).

But good to know it can be done - thanks :slight_smile:

5

Hi - thanks for the reply.

MCS is good to know about - cheers for that…

Is SEG different from FIT? Am I limiting my options by wanting feed-in to grid and the ability to safely island the installation?

If so, it would probably be the case that a more traditional setup with a Quattro II would be a better choice (quattro because I’d have an auxiliary generator input too for long power outages in winter where solar would run at a deficit).

And try to dump as much excess PV generation as possible into heating stored hot water, car charging and the like.

Many thanks for your reply - all useful stuff :slight_smile:

6

FIT was ended and replaced with SEG allowing suppliers to set their own prices. None of these should be limiting factors in any way, but maybe more seen as options that may add additional components such as earth rods for backup power setups.
Depending on your usecase, feeding in may not even make sense with an EV and hotwater diverter, but having it won’t hurt. A generator makes sense if you did have prolonged power cuts in the winter.

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Hi,

Ah - I see (re FIT). It will be interesting to see what the estimated payback on SEG would be (summer surplus PV vs winter output) - I have some solar calculators that give me the typical kWh generation in a month, by month, in specific locations in the UK. Time to put up a spreadsheet…

Thanks very much :slight_smile: