Solar Panels

[Deleted User]

xeny said:

A question about the iBoost and similar diverters. How much power does the array need to have surplus to household demand for a 3KW immersion heater to heat a tank usefully. Is say 1KW enough, or realistically do you need 2 KW or more?

From the EDDI FAQs:

"Our eddi will divert even the smallest amounts of surplus, often see it trickling in 0.1, 0.2kW etc. You can set a minimum'.

The immersion heater isn't bothered by this. The EDDI uses Varisine technology to ensure compliance with Grid standards.

For an EVSE, using surplus solar the surplus output has to be above 1.3kW.

rjmachin

[Deleted User] said:

Alnat1 said:

Octopus are in it for the long run, they aren't going under anytime soon. They are always looking to a future of sustainable energy and have the best options for customers who are doing the same.

So good rates for those with EVs, cheap overnight charging, really good (best in market?) rates for solar export (not available together with cheap overnight rates, that would be too good) decent TOU (time of use) rates.

I'll just add, battery fitted with PV system would be VAT free, added later would incur VAT. The system needs to be installed by an MCS registered company and you received a certificate from them which is needed to obtain SEG payments. For an larger array (over 4-5kWh) you'll need DNO approval or you'll be unable to export more than 3.68kWh and the output will be capped. The solar company will sort this but it is an extra expense and there's no guarantee permission will be granted.

DNO sign off on the completed installation is also required before the supplier will apply to the DNO for an export MPAN. My sign off was a short email from SPEN confirming that it had received and was content with the commissioning and testing paperwork.

How long did it take you to get the DNO sign off?

My DNO is western power, who do not charge for it.

However, I ordered the solar panels in May, my solar installation company asked me to sign a letter authorising them the chase the DNO for updates around mid June (I asked them to complete the application as I had no idea what I was doing).

My solar panels were installed late July.

I am now exporting a lot more than I can use (Battery due early September), but need a letter/email before I can apply for SEG.   I called solar company today, who said they would contact me when they get email / letter from DNO.

I don't know how long it usually takes

[Deleted User]

My DNO application went through in about 3 months and before my array was installed. It cost £350. Trust me - you will have paid for this as part of your installation cost. 

Presumably, your initial application included the battery? If so, the DNO may be waiting for this to be installed before sign off. The DNO needs to see evidence that the solar and battery will be isolated from the Grid in the event of a power failure. The installer has to go through a commissioning test list which includes noting down isolation times etc. In extreme circumstances, the DNO can insist on ‘witness testing’ at an additional cost to you.

 Post commissioning sign off on my solar/battery took about a month. We were still in partial lockdown.

Alnat1

Northern Powergrid is my DNO and their letter is dated 17/3/22. Install was 3/3/22 but I don't know if installer applied before or after the system went in.

[Deleted User]

Alnat1 said:

Northern Powergrid is my DNO and their letter is dated 17/3/22. Install was 3/3/22 but I don't know if installer applied before or after the system went in.

What size is your array (sorry if I have missed that)? If it is less that 16 amps per phase (3.68kW) then the DNO has only to be notified. More than 3.68kW and when you are installing a AC battery WITH AN ISLANDING CAPABILITY prior DNO approval is required for the installation. 

The DNO will review your proposed connections (you provide a detailed schematic along with the technical specifications for the inverter and battery). The DNO will review your local Grid infrastructure and it may impose a maximum site export limit which could be less than your solar plus battery. For example, a 5kWP array with a Tesla PW2 could export 10kW and the DNO might impose a maximum limit of 6kW. This has to be managed by your inverter settings.

There are reports of DNOs restricting the use of solar installations whilst they carry out their review. Your installer should have been all over this as your agent. Once everything is in order, the DNO will usually issue a Connection Approval Notice. Mine runs to a couple of pages.

Edit: My system has islanding built in and solar output continues when their is a Grid outage. Non-islanding systems are required to shutdown in the event of a Grid failure. I have forgotten that important difference.

https://blog.spiritenergy.co.uk/homeowner/dno-permission

rjmachin

[Deleted User] said:

My DNO application went through in about 3 months and before my array was installed. It cost £350. Trust me - you will have paid for this as part of your installation cost. 

Presumably, your initial application included the battery? If so, the DNO may be waiting for this to be installed before sign off. The DNO needs to see evidence that the solar and battery will be isolated from the Grid in the event of a power failure. The installer has to go through a commissioning test list which includes noting down isolation times etc. In extreme circumstances, the DNO can insist on ‘witness testing’ at an additional cost to you.

 Post commissioning sign off on my solar/battery took about a month. We were still in partial lockdown.

Thank you, that probably explains it then.

My battery is not due in stock until next month and was ordered with the solar panels.   It is also a 5.18kWP array so may also take longer.

[Deleted User]

I hope that it works out well for you. I may be wrong, but I think in this rapidly changing market (with quoted prices being held for a month according to an email that I got from my installer yesterday), some installers are carrying out installations and seeking retrospective approval (or just leaving it to the purchaser). What could possibly go wrong?

markin

Some of the Octopus tariffs are loss making Tests aren't they? I forget which tariffs...

[Deleted User]

markin said:

Some of the Octopus tariffs are loss making Tests aren't they? I forget which tariffs...

Go and Go Faster EV tariffs were said to be loss leaders - but with recent tariff increases, I doubt that is the case now.