Solar Panel Advice - Second system

[Jimmyrn85]

Good afternoon all!

I've recently moved into a house which has an existing solar system.
The system is around 12 years old, it is 3.96kw. South facing. 12 panels, my man maths states that they would be 330w panels and probably significantly less than that now due to their age. There is a large Growatt inverter in the loft (I'm unsure of the model).

There is a lease arrangement in place. Which getting the right paperwork from the seller to satisfy my lender was a nightmare (basic things like was the system installed by a competent company). The basics of it are.... The system was installed for free for the previous home owner. The home owner can use as much of the lecci generated at any given time, the homeowner cannot store any of this lecci. The panel installer gets the nice FIT payment which was available 12 years ago. There is 13 years left on this lease. The solar company takes care of any maintenance required and that is that.

So far... I'm happy, I've noticed a reduction in my lecci bills from only being in the house a few months compared to my previous property (and of course we have had nice weather in southern England recently!) With me and the Mrs working from home and using the dishwasher / washing machine during the day it pretty much covers all our loads. Our heating and hot water is gas.

This leads me on to a question for you all please.... especially after reading the wonderful DIY post by Ron-Ski.

There is a decent amount of roof space on the garage, which is also south facing.

Can I, install a second solar system (another inverter, bunch of panels, batteries and any other auxiliaries as required) which is grid tied, but is not allowed to export?

Thinking out loud... A second system would charge batteries during the day, then as the leased system runs out of sunlight in the early evening, can the second system be set to start discharging the batteries to maintain house loads? Would there be no need for G99 stuff because there is already an approved system in place for exporting?
If this is achievable, any advice and guidance would be much appreciated.

Am I able to as a reasonably competent DIY'er (not to Ron-Ski's level) install the solar panels on the roof and connect up to a new inverter but get a proper sparky to do the connection to the house consumer unit? I notice Ron-Ski had the sparky connect the panels up too.

Cheers!

 

[Jimmyrn85]

Thanks SJA. I don't want to feed in, want nothing to go to the grid, but I still want it grid tied (so it can easily connect to my house mains and power the house via batteries).

You can buy your way out, but it is very expensive and not worth doing. It is a sliding scale, but it's like 20grand at the moment.

 

[Jimmyrn85]

It's a risk as you've highlighted, however the pros outweighed the cons for us, location is exactly where we wanted to be.

I don't want to add batteries to the existing system, I'd like to make a totally separate system in the garage. But if you think it will interfere with the original system then I guess I will talk through my options with them.

Thanks for the info on the G99/G100.

Yes this is the interesting part I feel, if the new system could be somehow configured to not do anything but store energy during the day (maybe even isolate it from the main consumer unit during the day?) then as the sun goes down, it is then connected and allowed to support the house loads but send nothing back up to the grid.

Current system is connected directly to consumer unit, has it's own meter (or a standard export meter) I don't know much at all about that extra meter.

Thanks, makes sense ref the MC4.

 

[Jimmyrn85]

I have 3 smart meters, lecci and gas and solar. The meter to do with the solar gets read by them remotely, basically the homeowner has nothing to do with the system. My hunch is there isn't a deemed export, it is all metered.

Thanks for info, I'll make some enquiries and start plotting!

 

[Jimmyrn85]

Thanks, currently on a ship... Back home in a week and will update once I've done some more digging. Cheers

 

[Jimmyrn85]

Yes there is a buyout clause, but it is not in their interest to sell it to you, hence it's very expensive. I don't have the figures in front of me but it is something like 20grand to buy it out now (it's about 12 years old) and it decreases each year but not by much!

 

[Jimmyrn85]

Ah ok thats a shame. I know contracts vary a lot.

Whats the end of 25 life options?
Do the panels resort to being yours or theirs or what?

Haha good question! Yes around 2036 lol... It becomes ours (or the next home owner!) or you can get them to remove all the kit at their expense. Will it still be working by then? Will 300ish watt panels be capable of 50w then?! lol. If it breaks, they cover costs etc up till then.

 

[Jimmyrn85]

Only one way out of it, and you need to check the T&C's - Have the system condemned as dangerous by another electrician and get it disconnected, they then have to prove it is safe, sometimes it isn't worth their time and aggravation and they'll agree to let you remove it.

Interesting angle!

I'm not sure it would wash! I had to get certs to confirm it was installed correctly by a certified company etc etc to satisfy my lender.

Also, I'm not unhappy with the system! Even if the terms seem to suck! I get free lecci during the day. I'd just like to have a second system, but also connected to my consumer unit to power the house in the evening.

I have had a look through my T&C's whilst I'm on the ship here:

2.4 If the Landlord wishes to carry out alterations or additions to a part of the Building which is in the vicinity of the PV System or any conduits serving the PV System, then the Landlord may do so if the Tenant first consents to this in writing and, if the Landlord demonstrates to the Tenant that such alterations or additions will not interfere with the operation, efficiency, productivity of or access to the PV System then consent will not be unreasonably withheld or delayed.

3.2 The parties agree that any electricity generated by the PV System may be used by the Landlord for the benefit of the Landlords Property and that any electricity which is not used will be exported to the grid for the sole benefit of the Tenant.

 

[Jimmyrn85]

Thanks all, really appreciate your insights etc.

Having read another document I have from the house purchase "deed of variation" it does unfortunately state it cannot be stored:

7. Use of the premises, the electricity and ownership of renewable benefit payments
7.1 The landlord may use any electricity generated by the PV system as it is generated for the benefit of the property and the landlord agrees and covenants (as possible):

7.1.1 that any other electricity will be exported to the grid for the tenants sole benefit;
7.1.2 to comply with any safety procedures and measures that the tenant informs it of in writing from time to time;
7.1.3 that it will not store any electricity that is produced by the PV system; and
7.1.4 that it will do all things reasonably necessary to ensure that the tenant has the benefit of any renewable benefit payments.

8.2 In the event that the landlord wishes to carry out roof repairs and the tenant is required to temporarily remove all or part of the PV system from the premises, then the tenant agrees to do so to the extent necessary subject to the landlord paying the tenant within 14 days of demand:

8.2.1 (if this results in the tenant not receiving its anticipated Renewable Benefit Payments for a period of more than 3 consecutive weeks or more than 6 weeks in total in any 12 month period (or such other period(s) that may be agreed by the parties from time to time (acting reasonably)) (the "Grace Period")) a sum equivalent to the Renewable Benefit Payments which the tenant would have received from the end of the grace period until the date that the PV system is re-installed at the rate anticipated (using Renewable Benefit Payment Records as a benchmark) by the tenant for that time of year; and

8.2.2 the tenant's reasonable and proper costs in connection with the removal and subsequent re-installation (including the price of replacing any part of the PV system which cannot be re-used after removal).

In that same document at the bottom is the buy out price too:

Year of the term during which the break notice is received by us:
Year 11 - 18,720 (excluding VAT applicable at time of purchase)
Year 12 - 18,360
Year 13 - 17,640
Year 14 - 16,920
Year 15 - 16,200
Year 16 - 15,480
Year 17 - 14,400
Year 18 - 13,680
Year 19 - 12,240
Year 20 - 11,160
Year 21 - 9,720
Year 22 - 7,920
Year 23 - 6,480
Year 24 - 4,320
Year 25 - 2,160

I will be speaking to the solar company when I get home, it's proving very useful to get your opinions though thanks. I just hope I can run a second system which won't interfere with the current one somehow, with the idea that it doesn't export too.

The garage doesn't provide access to the house roof panels. As far as I'm aware it is the original inverter, it is a large looking Growatt inverter... Much larger than a friend who has a modern Growatt with a similar rated system.

Nobody comes around, they monitor it all remotely and do nothing.

So anyway, Ron-Ski, I need to check it has a CT clamp when I get home?

 

[Jimmyrn85]

Comment on inverter was with regards to whether the system will still generate decent amounts in 25 years not in regards to adding or changing, not sure how you got that idea.

And yes my point was that its likely the export wont be controlled as its within allowance and hence right now adding another system will require change.
Cant simply add another system as that will potentially over export, and if export is limited based on the T&Cs its going to need to have export priority.

@Jimmyrn85 I assume from the T&Cs that you do not get the normal export payments at all? IE not FIT (obviously) nor normal export payments?
The T&Cs would seem to indicate that they receive the amounts in excess "any electricity which is not used will be exported to the grid for the sole benefit of the Tenant"
It would seem odd to put that if they are on deemed exports.

Yep I get nothing. It's all for them!

 

[Jimmyrn85]

Has a Gledhill Boilermate 2000 heat store!
Fed from a gas boiler downstairs. It has emergency immersion backup.

I’m told these heat stores are efficient, but are relatively unreliable. Doh!

So in some ways is it good news with this rent a roof system… if it doesn’t have a CT clamp etc, I can install another system with batteries, and set that to no export and the people who get the FIT will be none the wiser?! Lol