Solar export problem?

[patp]

As I use a laptop the photo thing is hard for me to arrange. The easiest thing for me to do is to the main guy out from the electrical contractor. We got on very will with him and he is a wiz with solar. As I said above we were promised a visit by their solar main man that never happened because of staffing problems at the company. We need to discuss a battery installation so that will give them an incentive to come out and talk us through what is going on

Just now, billt said:

If it's a 3 phase PV system but the house is only on one phase then you're likely to be only consuming 1/3 of the PV output.

Ah! that is very interesting! Yes it is 3 phase.

[Radian]

Just now, patp said:

Ah! that is very interesting! Yes it is 3 phase.

 

The house? Or just the Solar PV? If the house is only on a single phase, it will limit the power available to you, to 3.84kW. Without an export contract the other 7680kW is just going to your neighbours, who probably pay the utility company 34p/kWh for the privilege.

[patp]

From memory! The house is on one phase, the garage/workshop (not yet built) is on another and the third was to export to the grid in return for payment. 

[Radian]

So you've had a total of 2833 kWh available to the house (what your generation meter reports divided by three) but of that, unless you have a diverter set up to route excess to HW, you will have been lucky to consume half of it - even if you try timing use of big appliances to when the sun is shining. Batteries work around this problem, but your big array is mostly only going to work for you with a decent export contract.

[Dillsue]

What's the model number of the Emlite unit with flashing lights(probably a meter) and how many wires are connected to it? Whats the model number of the solar inverter? Might be able to guess a bit more accurately how your system is set up, but if its a single phase inverter with the 3 phase supply configured as you remember, you might not be using any of the solar generation!

[Radian]

13 minutes ago, Dillsue said:

but if its a single phase inverter with the 3 phase supply configured as you remember, you might not be using any of the solar generation!

 

I've been assuming that given the generation meter shows 8500kWh, it won't have all gone out on the one phase. Maybe the DNO accepted that but it's unlikely given that all three phases are available.

[SteamyTea]

56 minutes ago, patp said:

The house is on one phase, the garage/workshop (not yet built) is on another and the third was to export to the grid in return for payment. 

If the PV has really been set up like that, a claim against the installation company is in order.

 

[ProDave]

Please find a way to post photos.  If you use a phone to take pictures, you can access this forum on a browser on your phone so it should be easy to upload them.

 

It sounds like you don't really know how it is wired. It may or may not be wired in the optimum way.  Who advised you to fit 8.5kW?  that is a lot to hope to self use, so for that much, you meed either batteries to increase self usage, or justify it on export payment.  And if your chosen method of payback was export payment, then you must have the install done by an MCS contractor who would certify it so you can claim the export payments.  Were they MCS and have you got the paperwork from them?

[patp]

We are going the battery route but waiting for the garage to be finished to install it. We are waiting for the MCS number to register it with Octopus. Again the contractors are blaming the office manager for all these failings. We have a very good relationship with them but might have to stand our ground if it proves to be their failings that have cost us money in the long run. The chap who owns the business is a bit of a wiz kid with solar and has been granted, since we were sold our deal, huge contracts with local authorities etc. I think we got lost in the productivity drive  The 46 panels were sold to us on the basis that we would get a 5% discount and that we could cover all our costs and sell what was left over back to the grid. 

I will try with the photos tomorrow.

[SteamyTea]

17 minutes ago, patp said:

The chap who owns the business is a bit of a wiz kid with solar and has been granted, since we were sold our deal, huge contracts with local authorities

Better to have a decent office manager than a 'whizz kid'.

PV is mature technology, basically installs itself.

If you could connect up a 1970 stereo system, you can do PV.

 

Tell him for the right money I will sort out his crap installers.

[Dillsue]

25 minutes ago, patp said:

We have a very good relationship with them but might have to stand our ground if it proves to be their failings that have cost us money in the long run.

Unless you specifically asked them to sort out a SEG contract for you, and I dont think thats the norm, it would be you that would sort out an export payment contract, as you are doing now with Octopus.

If you'd asked for the MCS certificate when the system was installed, but they didn't supply it, then you might have an argument that the loss of export payment was their fault. If they're an MCS acreddited installer then you'd likely be able to make a complaint to MCS but not sure you'd get your lost export payments reimbursed???

Edited November 13, 2022 by Dillsue

[Radian]

3 hours ago, ProDave said:

And if your chosen method of payback was export payment, then you must have the install done by an MCS contractor who would certify it so you can claim the export payments. 

 

For everyone's reference, exactly what paperwork should people make sure they've got from an installer once the job's complete?

[ProDave]

8 minutes ago, Radian said:

 

For everyone's reference, exactly what paperwork should people make sure they've got from an installer once the job's complete?

I don't know for sure these days, but when I had my 2011 FIT system installed the paperwork package from th eMCS installer included various certificates to confirm the equipment was new, was owned by you, had been correctly installed and various drawings about the instalation.  These needed submitting then to the FIT provider.

 

I assume it is much the same.  the key thing it must be signed off my an MCS installer.

[Dillsue]

2 hours ago, Radian said:

 

For everyone's reference, exactly what paperwork should people make sure they've got from an installer once the job's complete?

To get export payments, I beleive you need the MCS installation cert and the installer to register the install on the MCS database. I beleive some or all SEG payers want a letter from the DNO confirming the grid connection is accepted.

 

On top of those you want elec test cert, warranty details, operation guide. Details of any non standard settings theyve made together within any usernames and passwords. A list of component model/part numbers would be useful in the future for getting spares sorted.

[SteamyTea]

MCS has a system registration database. Don't think it is public though.

 

Call up MCS and ask.

[Radian]

49 minutes ago, SteamyTea said:

MCS has a system registration database. Don't think it is public though.

 

Call up MCS and ask.

https://certificate.microgenerationcertification.org/

Tried a few username/passwords but no luck.

[patp]

The contractors have already applied for it. It should have been applied for long ago but the duff office manager did not do it. They couldn't be more apologetic but that does not help us does it!?

[Radian]

11 minutes ago, patp said:

The contractors have already applied for it. It should have been applied for long ago but the duff office manager did not do it. They couldn't be more apologetic but that does not help us does it!?

 

Great. Now you've got a bargaining tool. What else might you need at trade price? Seriously, you've lost out financially due to their incompetence and while you'd have an uphill battle getting any cash compensation out of them, they have some potentially cost free favours they might do for you to make amends. Do you have PV divert to your HW immersion heater?

[patp]

Will do my best to squeeze them for what we can get. We are intending on getting a battery for the solar so might be able to strike a deal on that.

 

No to the PV divert to our HW immersion heater. Husband is a retired plumber so he could figure it out if the sparky was to help.

[SteamyTea]

10 minutes ago, patp said:

We are intending on getting a battery for the solar so might be able to strike a deal on that.

Get the main problem sorted first.

You don't want to charge batteries to then just export 90% of what you have generated (assuming your PV is on an unused for import phase).

[patp]

Oh yes. Getting that sorted is our main priority. Selling us a battery set up might just lure them here a bit more smartish

 

Feeling despondent today. Got a bill for the scaffolding on the garage, which has hardly been used due to one hold up or another - sigh.

[Radian]

15 hours ago, patp said:

No to the PV divert to our HW immersion heater. Husband is a retired plumber so he could figure it out if the sparky was to help.

Assuming that you heat your hot water with a gas boiler:

With export tariffs as low as they are, it pays to consume as much of the energy you generate as you can. A solar PV diverter to immersion heater squeezes every last drop of solar PV energy into heating your hot water before it ends up being exported for peanuts. It's much more cost effective to store energy in hot water than in batteries.

 

[SteamyTea]

18 minutes ago, Radian said:

It's much more cost effective to store energy in hot water than in batteries.

Yes, but only if you can utilise it.

@ProDave would flush any left over down the drain.

[S2D2]

1 hour ago, Radian said:

Assuming that you heat your hot water with a gas boiler:

With export tariffs as low as they are, it pays to consume as much of the energy you generate as you can. A solar PV diverter to immersion heater squeezes every last drop of solar PV energy into heating your hot water before it ends up being exported for peanuts. It's much more cost effective to store energy in hot water than in batteries.

 

Whilst usually true, I assume this is an MCS install so eligible for the current 15p octopus outgoing export rate vs ~11p gas offset? Obviously this rate can disappear overnight so an immersion divert may be a longer term plan, especially if it's part of a negotiated recompense as suggested above.

[Radian]

3 hours ago, S2D2 said:

Whilst usually true, I assume this is an MCS install so eligible for the current 15p octopus outgoing export rate vs ~11p gas offset? Obviously this rate can disappear overnight so an immersion divert may be a longer term plan, especially if it's part of a negotiated recompense as suggested above.

It's a closer call than that though.  11p gas per kWh goes through a less than 100% conversion process when burnt in a boiler. It depends on the type of boiler and the flow temperature etc. To me it's almost as if they set the tariff accordingly.