DIY solar battery storage

[Berserkerboy]

I would like to retrofit the above.
I have a diy plug in solar system using microinverters which has been accepted by the DNO. I receive no feed in tariff and end up exporting energy for free once the solar diverter has heated our hot water.
Do I have to have an MCS installer to add battery storage for me? I have had quotes from installers but the price for the equipment is sometimes twice the price I would pay if I bought direct! Not to mention £400 for a few hours work.
Also, are batteries exempt from VAT after April 1st?

 

[ProDave]

I can't answer the first question, but it appears that the "0% VAT on energy efficiency measures" ONLY applies to supply ad fit. Go and buy the material for DIY and it's still 20%. Jobs for the (mcs) boys?

 

[binky]

as with Solar PV,the only requirement is to notify the DNO, MCS is nothing to do with it. NB if you have separate solar inverter and battery inverter, the DNO regard this as 2 items connected to their grid, and may refuse one connection on the basis that combined they would exceed 16A. I would talk to them before installing, or just ignore that and out in anyway

 

[Berserkerboy]

Thanks guys. Yeah, had a reply from an MCS installer today. They say that as it's just a battery install that there is still 20% VAT. Misleading headline from Sunak....Who'd have thought?!

Interesting the two inverter situation with the DNO. I'll ask them.

 

[Berserkerboy]

The MCS cartel is a joke. Especially if you are using microinverters as they are pretty much plug-and-play. The law should be changed to allow normally qualified electricians to do microinverter installs and allow people to at least get a small payment from the grid for exporting.

 

[binky]

The MCS cartel is a joke. Especially if you are using microinverters as they are pretty much plug-and-play. The law should be changed to allow normally qualified electricians to do microinverter installs and allow people to at least get a small payment from the grid for exporting.

there's nothing in law to stop anyone doing an entire solar installation, the only legal requirement is a G99 or G100 grid tied inverter and notiifcation of DNO. All MCS got you was access to FiT payments, and they have long gone, so I told MCS and Ofgem and all the other money grabbing quangos to pee off years ago as it was costing about £3k a year to be registered.

 

[Berserkerboy]

there's nothing in law to stop anyone doing an entire solar installation, the only legal requirement is a G99 or G100 grid tied inverter and notiifcation of DNO. All MCS got you was access to FiT payments, and they have long gone, so I told MCS and Ofgem and all the other money grabbing quangos to pee off years ago as it was costing about £3k a year to be registered.

I don't blame you. £3k takes a bit of recovering.
I had resistance from the DNO when I informed them of my installation. They initially said it had to be installed by someone who was MSC qualified. I replied that it had been connected to IET regs. Finally, they accepted it. I can understand the need for safety but I had sent them the electrical diagram and listed the compliant components. The microinverters are class 2 and simply daisy-chain together and then connect via a spur to the ring main.
I really don't understand why this kind of install isn't good enough to qualify for SEG.

 

[binky]

I don't blame you. £3k takes a bit of recovering.
I had resistance from the DNO when I informed them of my installation. They initially said it had to be installed by someone who was MSC qualified. I replied that it had been connected to IET regs. Finally, they accepted it. I can understand the need for safety but I had sent them the electrical diagram and listed the compliant components. The microinverters are class 2 and simply daisy-chain together and then connect via a spur to the ring main.
I really don't understand why this kind of install isn't good enough to qualify for SEG.

Shouldn't be wired to a ring main. The inverters official spec is to shut down within 3 secs of loss of mains, so they could be killing someone long after the RCD has tripped

 

[Berserkerboy]

Really? It's how Plug in Solar tell you how to connect the system.
How should they connect?

 

[binky]

solar shoud be on it's own cct back to the consumer unit for the safety reasons I outlined above

 

[Murdoch]

solar shoud be on it's own cct back to the consumer unit for the safety reasons I outlined above

AND when on its own circuit it shouldn't be on a shared RCD either

 

[Berserkerboy]

Okay. I understand. Fortunately, this is the case with our system. When the installation was connected we had a new consumer unit put in as we were still only protected by MCB's. The solar has a dedicated RCD.
How can Plug-in solar get away with saying you only need to connect via a spur?

 

[Murdoch]

How can Plug-in solar get away with saying you only need to connect via a spur?

Because it’s plug in . ..

 

[Berserkerboy]

The spur will not be on it's own RCD though. It's a spur off of an existing ring they advocate.
Confused.... But anyway, happy mine is to safety standards.

 

[binky]

How can Plug-in solar get away with saying you only need to connect via a spur?

Coz they don't give a toss Depends when you bought it. It was on this very forum we worked out the safety issues, and it took a while longer to be written in to the standards.

 

[Berserkerboy]

.
If I'm allowed by the DNO to have the batteries I have a spare RCD for that as well.

 

[Berserkerboy]

Still awaiting a reply from the DNO but thought I'd ask a further question regarding installation of battery storage.

Initially, I had 8 panels connected to the consumer unit. I added a further 4 panels connected to a sub-panel in an outbuilding on a dedicated RCD. All our panels are on ground arrays facing east, south and south west to smooth generation. I needed planning permission, which is another farce in itself. I agree that permission should be sought but disagree that a planet benefitting application if agreed should be charged £460!

I have a Solic 200 immersion diverter controlled by a CT clamp sensor on the grid side of the meter +ve cable.

So I have power coming in from the panels to 2 connections at the consumer unit in the house.

I'm just wondering if I'm going to have issues setting up a battery system where the CT clamp isn't in competition with the Solic CT clamp. Ideally, I'd like the battery to charge up first followed by the Solic diverting to the immersion.
Also, the battery wiring diagrams I've looked at have a production CT clamp around the solar cable to sense generation. I have 2 cables carrying generation. So is this sensing necessary? I don't need to know how much they've made.

Sorry it's all a bit confusing. Hopefully, you can visualize what I have described..

 

[binky]

CT clamp should be on the meter tails between your service head fuse and consumer unit. Not sure what will happen with 2 clamps, they won't interfere with each other as such, but the Solic works from very low wattage being exported - might be worth trying to find a similar control or older version. The older version worked from around 150W being exported, so that would allow battery to charge first. Other controls work in similar ways, my own works from 200W.

 

[Berserkerboy]

Thanks for that. I guess if the water heats first that wouldn't be the end of the world.
This morning, by around 10am, we were exporting 2.4kw as the immersion was up to temperature..
If the battery started charging after that it would have plenty of time to charge..

 

[Berserkerboy]

Reply from the DNO. Incidentally, I had to chase and chase it!
Yep, they want a full G99 application due to the AC coupled inverter adding to the theoretical export possibility.
They want the certification of all the proposed equipment and existing.
Also, a full schematic so that they can model whether the grid can accommodate the addition.
I can draw the schematic using Libre Office. I'm wondering if this will be acceptable or will they require a recognised professional electrical drawing? I suppose I can put it in and see if it gets bounced back.