Solar Production Thread

Page may contain affiliate links. Please see terms for details.
OP
OP
J

jowwy

Can't spell, Can't Punctuate....Sue Me
HTTPS://Pvwatts.nrel.gov is calculator / prediction tool

It reckons I will get 407kWh for October and I'm currently at 418kWh for October but it's been a pretty sunny one so far.

It is predicting 148kWh for December (about 4.8kWh a day) and 216kWh for January (7kWh a day).

I have a 7kw array.

Its telling 67 for december and 77 for january……but will see
 

CXRAndy

Guru
Location
Lincs
I never knew that. It does seem unfair if that is true.

It seems odd that the limit is set high enough that is likely to be an issue.



We haven't done either of those.

You must be only a few on your particular section of the network.

To give you a costing of what could be involved with an upgrade. There is the cabling back to the substation, any transformers that might be on the line.

A friend has just had the DNO upgrade their street. Part of the upgrade was a new 3 phase transformer. Not a more powerful one just new. He was speaking with the installation team about getting solar. They said the transformer alone is £35,000. I know this is roughly correct because I wanted to build a new house which had a poor single phase . We asked for a price to 3phase. 13 poles, cabling and new transformer £75,000:eek:
 
OP
OP
J

jowwy

Can't spell, Can't Punctuate....Sue Me
Just 4.8kwh for us today, rained for most of the day. But its still covering our daytime base loads. Will be selling the excess soon, so that can cover evening use then.
 

Alex321

Veteran
Location
South Wales
You must be only a few on your particular section of the network.

Either that or (more likely in my view) the network in our area has already been upgraded. I feel that is more likely because there are quite a few houses around with solar on their roofs.

Incidentally, I have just re-read the "offer" letter from Western Power Distribution (Our DNO) to Tile Energy, and it seems we are limited to 7Kw export on our 10Kw system.
Basis of the Connection Offer
2.1 Customer’s Installation
2.1.1 WPD understands that, based on current information provided by the Customer, including
within the Customer’s connection application, the Customer's Installation will comprise the
following:-
 Total installed 10kW PV with an export of 7kW PV.
2.2 Supply Specification for the Proposed Generation Equipment
2.2.1 The characteristics of the Customer’s Installation(s) will be:
Nominal Voltage at Connection Point: 230/400 Volts
No of Phases: 1
Nominal Frequency: 50 Hz
Maximum Export Capacity: 7kW
Maximum Import Capacity: 15kVA
External Earth Loop Impedance: Existing connection
Maximum Prospective Short Circuit Current: Existing connection
Acceptable Power Factor for Export Capacity: 0.98 lead to unity.
Acceptable Power Factor for Import Capacity: 0.95 lag to unity.
 

CXRAndy

Guru
Location
Lincs
Ah so they did specify export. In reality 3kW isn't going to overload the network. They just want to keep tabs on installations.
 

kipster

Guru
Location
Hampshire
Regarding the 7kw export,.do you have a 7kw inverter? If you do the installer would have put that on the g99 document and then the DNO say that's your max export.

Mine max export is 5kw,.just so happens I have a 5kw inverter. If I increase then I would need to reapply.
 

CXRAndy

Guru
Location
Lincs
That would be a waste of solar panels if the inverter couldn't supply the peak capacity.

Inverters can be software controlled to limit output to grid-G100 compliant

Id suspect that it could be passive, the owner is possibly taking some energy or is hardly ever near peak, so 7kW is not reached that often
 
Last edited:

Alex321

Veteran
Location
South Wales
Regarding the 7kw export,.do you have a 7kw inverter? If you do the installer would have put that on the g99 document and then the DNO say that's your max export.

Mine max export is 5kw,.just so happens I have a 5kw inverter. If I increase then I would need to reapply.

No, it is a 10kW inverter. I have seen 9.5Kw out of it, which is close to max expected.

It just won't export at more than 7kW.
 

Alex321

Veteran
Location
South Wales
That would be a waste of solar panels if the inverter couldn't supply the peak capacity.

Inverters can be software controlled to limit output to grid-G100 compliant

Id suspect that it could be passive, the owner is possibly taking some energy or is hardly ever near peak, so 7kW is not reached that often

That last is true. We have only had a few days in September/October when production has briefly hit 7kW. Going back to August, it hit 8kW on quite a few days, with most being between 7 & 8 maximum.
 
Last edited:

MrGrumpy

Huge Member
Location
Fly Fifer
That is quite impressive!

Unless one of my premium bonds gives me a big win, I am unlikely to have the money to invest in solar energy, but it interests me.

How much power would it typically generate on gloomy days in December or January?

Fortunately we have access to interest free loans up here . However I think that’s tempered with higher install costs ? Certainly looks like it ? £12/13k for 10kWh batt and 5kW solar array is standard. Max loan is £11k !
Not worth using all your own cash either way for me anyways . Thread digression !
 

MrGrumpy

Huge Member
Location
Fly Fifer
No, it is a 10kW inverter. I have seen 9.5Kw out of it, which is close to max expected.

It just won't export at more than 7kW.

Currently made a start on my loan application and have a quote from an installer . I doubt I’ll be exporting much from mine . We are high users , never below 10kWH a day , only drops below that when house is empty !
 

Alex321

Veteran
Location
South Wales
Currently made a start on my loan application and have a quote from an installer . I doubt I’ll be exporting much from mine . We are high users , never below 10kWH a day , only drops below that when house is empty !

We use a bit less than that - average about 8kWh per day over the year, more in winter less in summer. We got such a big system partly to be future-proof if we later get an EV or switch to electric heating instead of gas.
 

Alex321

Veteran
Location
South Wales
Fortunately we have access to interest free loans up here . However I think that’s tempered with higher install costs ? Certainly looks like it ? £12/13k for 10kWh batt and 5kW solar array is standard. Max loan is £11k !
Not worth using all your own cash either way for me anyways . Thread digression !

We were in the fortunate position of having plenty of cash. Not sure interest free loans are available in Wales, and we'd rather not take out an interest bearing loan.

For us it was £20K for 10.14kW PV array and 16kWh battery plus all associated bits and install.
 
OP
OP
J

jowwy

Can't spell, Can't Punctuate....Sue Me
We were in the fortunate position of having plenty of cash. Not sure interest free loans are available in Wales, and we'd rather not take out an interest bearing loan.

For us it was £20K for 10.14kW PV array and 16kWh battery plus all associated bits and install.

not currently, unless your a Social housing landlord and then its only grants to upgrade old houses
 
OP
OP
J

jowwy

Can't spell, Can't Punctuate....Sue Me
Fortunately we have access to interest free loans up here . However I think that’s tempered with higher install costs ? Certainly looks like it ? £12/13k for 10kWh batt and 5kW solar array is standard. Max loan is £11k !
Not worth using all your own cash either way for me anyways . Thread digression !

good luck on the loan request. but how long would it take to pay that money back if your a high end user and not exporting much??
 
Top Bottom