Solar Panel Guide Discussion

tunnel

Hi CC,
If you can fit 16 "standard" 250Wp panels on your roof then it may be an idea to get a few more quotes as sub £5k for an install is all the rage at the mo, no need paying for premium panels if it's not necessary and even less need for solaredge or equivalent if you don't have shading. We've seen prices as low as £4.5k and as there's no rush before the FiT drops again there's plenty of time to batter them prices down

CrazyCol

Thanks Tunnel
I've got lots of room for 16 panels & facing SSE with no shading issues, some more quotes came today 1 company 16 X 250w panels from amerisolar, or perlight black or Canadian solar all with a solis inverter between £4.2 and 4.6k or with a sunny boy 4000tl adding £250 to those prices, the problem I have is how to value the relative merits of each system.

tunnel

You need to decide which is best for you...cheap and cheerful or pay a little more for better known brands, I wouldn't worry about the merits...you'll drive yourself mad trying to work out the merits of each individual system setup...there's that many choices
At the end of the day one type of 250W panels will generate the same as the next, it's all down to you as to which is best for you, maybe take a little advice to help that decision, there are certain brands that seem more popular and have been around longer than others, that said, it doesn't necessarily mean they're better. It really is a minefield


Cracking prices by the way...£4200 for a 4kWp system, that's gonna take some beating!!

Martyn1981

CrazyCol wrote: »

Thanks Tunnel
I've got lots of room for 16 panels & facing SSE with no shading issues, some more quotes came today 1 company 16 X 250w panels from amerisolar, or perlight black or Canadian solar all with a solis inverter between £4.2 and 4.6k or with a sunny boy 4000tl adding £250 to those prices, the problem I have is how to value the relative merits of each system.

Flipping eck Col! Those prices and you're asking us for advice? :T

Can I ask where you are (roughly) as I'm sure many potential PV'ers will want to ask you for installer suggestions once your MSE restrictions are removed (being a 'newbie').

Mart.

ecomom

I think that the cleverest way is to get as much information before the installation as possible and just talking with friends is not enough. Before buying our solar panels my husband made an internet research and got numerous consultations from the specialists of Solar Panels Company. I really don't understand people, who are just complaining that something is going wrong. It is important to be aware of all factors before making a decision and remember about the responsibility. I like reading forums for this reason.

tunnel

ecomom wrote: »

I think that the cleverest way is to get as much information before the installation as possible and just talking with friends is not enough. Before buying our solar panels my husband made an internet research and got numerous consultations from the specialists of Solar Panels Company. I really don't understand people, who are just complaining that something is going wrong. It is important to be aware of all factors before making a decision and remember about the responsibility. I like reading forums for this reason.

Or post your thoughts and quotes on here to let fellow PV'ers run their eye over them, no one on here wants to see anyone pay more than a fair price for a system and to date myself and my fellow posters have helped and advised literally hundreds of people looking at getting a system installed.


Yet it still amazes me when someone like CrazyCol gets quotes like he has, some people have a gift

CrazyCol

Based in NE - Teesside, may end up with a slightly dearer system for a compromise on cost / quality / warranty.... £4.9k for 16 X 250W solax mono black with solax inverter, pairing up gives manufacturer 20yr warranty on both panels and inverter. UK support centre too. Would appreciate any info/experience on this manufacturer

tunnel

CrazyCol wrote: »

Based in NE - Teesside, may end up with a slightly dearer system for a compromise on cost / quality / warranty.... £4.9k for 16 X 250W solax mono black with solax inverter, pairing up gives manufacturer 20yr warranty on both panels and inverter. UK support centre too. Would appreciate any info/experience on this manufacturer

Can't say I've heard of solax before, that doesn't mean they're not good though.
Looking at your previous quotes, Canadian solar(bobs) and an SMA was coming in cheaper wasn't it? Both have been around for a while and both will probably get good reviews on these forums, I personally know of several people with that set up and they're very happy with it(my father included). Not sure if SMA do a 20yr warranty though, I believe you can increase the warranty length, whether that's necessary is anyones guess as in 10 years when you may need a replacement inverter who's to say that any on the market today will still be around then, the warranty may not be worth the paper it's printed on.

Lei_Chat

tunnel wrote: »

At the end of the day one type of 250W panels will generate the same as the next, it's all down to you as to which is best for you...

Do some inverters and/or panels have better thresholds or is that just sales banter?

If I'm to believe the sales pitch the latest hardware can generate energy for longer each day in more cloudy weather than the older brands.

Martyn1981

Lei_Chat wrote: »

Do some inverters and/or panels have better thresholds or is that just sales banter?

If I'm to believe the sales pitch the latest hardware can generate energy for longer each day in more cloudy weather than the older brands.

It's sales banter. I get the cold calls and usually let them run for a while to see what spin doctor nonsense they are saying.

Generally, they all say the same at some point - "modern panels work on daylight, they don't need sunlight". That's true, but what they fail to mention, is that it's nothing new, the 'old' panels do exactly the same. All of us PV'ers know that panels work in daylight, but you get about 10 times more generation from sunlight.

My WNW panels work in the morning, and my ESE panels work in the evening * but they only generate a small fraction (10-20%) of what the system in the sun is generating. If it's grey and cloudy, then the systems generally perform the same, though the ESE will be approx twice the WNW due to array sizes.

* In perfect, clear blue skies, and I mean absolutely clear, which we only get a few times a year, then the system not in the sun may actually shut down as very, very little light is being reflected down onto them. Add a bit of white to the sky, and they generate again from the reflection.

Another consideration - any improvement in performance is important, and I'd never knock it, but a small increase in performance in cloudy weather or at the start/end of the day would be a small increase on an already small amount. So even if you boost 20Ws by 10% or 20% for 30 mins, it's not going to make a significant difference to your income.

Regarding inverters. They are all pretty efficient, probably between 92% and 98%, with most in the 95% to 97% range. Each 1% difference in efficiency could mean about 20 to 40kWh per year, so worth considering, but you do also have to consider the cost of the inverter. Interestingly, some of the cheaper Chinese inverters, that have earned some respect now in the UK, are both cheap and have high efficiencies, plus their warranties aren't bad either. But they don't typically, have as good a shade management software as some of the more expensive (German!) inverters. This may (or may not) be an issue depending on roof shading.

Another practice, particularly in the UK, is to undersize the inverter slightly compared to the panels. Perhaps installing an inverter that is about 10% smaller than the array. This makes it a bit more efficient during low generation periods, but may result in a small amount of capping when the system is at full belt, though this is very rare, and hot panels quickly drop off 10%.

Mart.