First quote

hollie.weimeraner

Upwind wrote: »

I have CTS Renewables doing my panels tomorrow - I'll let you know how things go. They have been good to date and I have had no problems....... let's hope that this continues...

CTS renewables from Mansfield installed a 4kw system for me last weekend. Very pleased with the install and can honestly say they are the best commercial company I have ever used. I would recommend them to anyone on here for a Solar Install.

ely_ellis

No. 6 came in with the slightly lower quote on the price match, however I have asked them to quote for the same system and panels as no.3 and they cannot match it.
As the song goes... "Torn between two solars, feeling like a fool" ... etc...
Wonder if no.6 with throw in an iBoost, that may clinch the deal.
No.3 knows he's the cheapest and doesn't want to budge, however his inverter is the 3500, and no.6 has the 4000 (16A version), so in theory no.6 will give me an extra 180watts, unless I'm not thinking that one out correct.

michaels

For comparison I am getting 16x upsolar 250w panels with built in solar edge thingimy, solar edge inverter and iboost for £4800 all in, spread over 2 aspects (from TP Solar in Northampton)

ely_ellis

Now that is an excellent price, but they are probably way too far from me to cover my area.

Just been on their website, cannot see any deal that good on there. How did you manage that price?
They actually seem more expensive by over £1000 for the system I have been quoted for.

MEVW62

It's worth asking them, they just did mine on the Kent/Sussex border and they were off to Bournemouth the next day

ely_ellis

MEVW62 wrote: »

It's worth asking them, they just did mine on the Kent/Sussex border and they were off to Bournemouth the next day

So what was your quote if you don't mind me asking?

Martyn1981

michaels wrote: »

For comparison I am getting 16x upsolar 250w panels with built in solar edge thingimy, solar edge inverter and iboost for £4800 all in, spread over 2 aspects (from TP Solar in Northampton)

I wish you'd stop posting that deal, it leaves me slack jawed and unable to type for 10 mins each time I read it.

Dual aspect, Solaredge and Iboost (that must be worth £500+) ....... at any point did you consider asking for their first born too? :cool:

Mart.

michaels

Martyn1981 wrote: »

I wish you'd stop posting that deal, it leaves me slack jawed and unable to type for 10 mins each time I read it.

Dual aspect, Solaredge and Iboost (that must be worth £500+) ....... at any point did you consider asking for their first born too? :cool:

Mart.

Well the plan was the 285w higher volatge seraphims in a 4 / 10 configuation with a sunny boy but then a day before they realised they couldn't get the panels until July and had committed to installing before the FIT reduction so switched to this package and as I had already paid the deposit they felt they couldn't increase the price. I suspect others won't get such a good deal but full marks to TP Solar for honouring what they had agreed to originally.

I guess using the upsolar panels with the built in controllers makes it cheaper and then the solar edge invertor is a bit cheaper than the SMA one so perhaps the overall parts cost is similar?

ely_ellis

michaels wrote: »

I had already paid the deposit they felt they couldn't increase the price.

Ah, that is how you did it, that makes a difference then!
I suspected there had to be more to it as their prices for a match on what I have been quoted so far is around £1000 more (not less).

Would someone like to comment on the inverter difference please.
One of the companies normally supplies the SE3500 inverter but they will do the same quote with the SE4000 16amp version.
However their explanation of why the SE3500 is that it will start to operate earlier and operate until later in the day where as the SE4000 is wasted capacity.
Looking at the specs, the way I see it is that I will loose 180watts because the SE3500 will only deliver 3500kw maximum.
Could someone confirm either way please.

Martyn1981

ely_ellis wrote: »

Would someone like to comment on the inverter difference please.
One of the companies normally supplies the SE3500 inverter but they will do the same quote with the SE4000 16amp version.
However their explanation of why the SE3500 is that it will start to operate earlier and operate until later in the day where as the SE4000 is wasted capacity.
Looking at the specs, the way I see it is that I will loose 180watts because the SE3500 will only deliver 3500kw maximum.
Could someone confirm either way please.

I'll take a punt, as this comes up every so often. But it's a 'jury's still out' question/answer.

Basically, in a climate like the UK, the system will spend a lot of time in less than ideal sunshine, so a smaller inverter that switches on earlier, and off later, and is slightly more efficient at lower levels of generation, may work better than a matched size inverter, or oversized inverter.

Depending on location and orientation, some (quite a few) installers may suggest a 10% to 20% undersizing. However, I'd be a little more doubtful if you have a south facing system in Cornwall, where the PV may be generating nearer the max for longer, than say an E/W split in Scotland, where you want to maximise lower levels.

Once the PV is in strong sunlight, it will get hot, fast (seconds) and will then drop about 10%, so a 3.68kW inverter is probably a very good size match for a 4kWp system.

Obviously, a 3.5kW inverter will only 'lose' upto 180W when potential generation is above 3,500W. Below that figure there is no loss.

If you have shading issues, then that would favour the 3.5kW slightly, if shading covers a large time band, since generation will be a little lower anyway.

Overall, since the price of the inverters is almost the same, I reckon it's a very tough call between the 3.5kW and the 4kW (capped). Not an answer, but hopefully a start!

Mart.

PS. Not really evidence, just a comment, but all three of my systems use slightly oversized inverters (difficult to get matches) and my generation is fine, perhaps slightly above expectations, so I'm happy. But, who knows, if I had smaller inverters, I might be even happier.