How to select an installer?

[SolarCity]

Not strictly true, some DNOs permit 16A x 240V = 3.84kW before prior permission is required.

Which DNOs are those?

 

[LightGEN]

NWEL will allow 3.84kW without prior enquiry.

 

[Worcester]

Still can't work out why you'd buy a SunnyBeam when Sunny Explorer is free..

 

[TonyL]

Still can't work out why you'd buy a SunnyBeam when Sunny Explorer is free..

Worcester, thank you very much. The answer is simple. Until this post, I didn't know Sunny Explorer existed. It certainly was offered as a monitoring option. I am somewhat miffed and it cerrtainly lowers my confidence in my installer quite considerably.

I have just downoaded Explorer and it won't recognise my plant, even with the PC next to the inverter for 10 mins. Any clues on linking the things up? I know the PC BT works as I have my Blackberry connected to it over BT.

 

[Worcester]

@TonyL

The installer probably hasn't configured the bluetooth in the Inverter correctly. Try Switching the SunnyBeam off.

There is a small configuration wheel inside the inverter, 0 is off, 1 is on (and can only connect to one device at a time), 2 - F can connect to multiple devices.

Download the Installation manual from the SMA Website if it isn't in your Handover pack, or better still get the installer back out to change it.

We often find that the built in bluetooth devices in laptops / pc's just arent't man enough to connect so nip along to Maplins and get a 100m Bluetooth dongle.

 

[BruceB]

There are 2 common problems:
- Set the Bluetooth dial on the inverter (the right hand dial) to something other than '0' or '1'. In other words to 2,3.....D,E or F. You want a 'channel' (not quite the right terminology I think but not going to look it up now) that no one else locally is using.
- Windows, depending on the flavour and update level can be flaky with Bluetooth. What I have found works if I am having trouble is to make sure the Bluetooth is active first through the Control Panel and run a scan of available connections. Once you can see it working then run up Sunny Explorer and it should work.

Regards
Bruce

 

[TonyL]

Thanks guys. Have been reading the install manual. Eventually got it working by updating my PC BT driver. The BT switch on the inverter had been left on 2 so my thanks to Evo. Not as sexy as the Sunny Beam but workable and you get all the data. I can't see a way of uploading to the Sunny website. Any thoughts ?

 

[series530]

I'm in the same position as the original poster: close to making a decision having had a number of quotes.

I thought I had hit gold with the first one (recommendation from a work colleague). He had the right answers and the right numbers and the price was attractive. He didn't go in the roof but he was sure that the age of the house told him enough. The second went over board with checking this and that and scratching his beard. I could see the pound signs. He wanted to go off and do some proper checking and a shade analysis (what ever that was). More pound signs! The third was reasonably thorough (he went in the roof) but I didn't feel that comfortable with what he was offering. His prices were OK.

Then, through this forum and a huge amount of reading I began to get the gist of what all of this stuff is about. I began to see what mattered and what didn't. Then the last quote came in - all bases covered, the full shading analysis. I got references and I followed them up. The quotes were not cheap but they were compelling - thicker cable results in lower loss and a higher harvest - compound that over 25 years and it makes a difference - stuff like that.

It's a huge investment ... a really huge investment. It needs careful thought:

Here are a few of the things that have mattered to me as a potential purchaser (rather than as an installer). Just a different perspective... and in no particular order:

If your motivation is return on investment, you are trying to maximise the energy harvest as this is by far the biggest pay back item in the FIT. The more power you harvest up to the limit, the more money the energy company is going to be paying you. Remember: the harvest is for 25 years if the FIT's run for full course. 1 percent more harvest could make a huge difference in ROI over 25 years. It may be worth spending a bit more to accumulate a lot. Get familiar with using Microsoft Excel and do some sums - you could learn a lot very quickly!!

Your harvest will be compromised by the radiance of the sun. You cannot control the sun but you have some control over the shading that objects cause. Shading really is a big problem. There is no point in stuffing your roof full of panels and finding that all of the strings are stunted by shade. Far better to have less strategically placed panels that avoid shade. The material and labour cost will be lower and you may end up having a higher overall output. Micro inverters will mitigate some of that but they will increase the installation cost. Some people like micro inverters, some don't, some are afraid of this new technology. Be open to options if any form of shading affects your array.

Reflections, clouds and goodness knows what will also cause secondary differences in panel performance. Coupled to a string inverter the compromise will affect the harvest. Micro inverters will help somewhat - but at a cost up front.

Beware of people siting panels close to gutters. You need about 10 inches of run off so that rain comes off the panel and gets trapped in the gutter. One company completely missed this point. Not ideal for the structural integrity of the house long term.

One company didn't bother to look in the roof. He was satisfied that the age of the house was enough of an indicator. This worried me greatly. Cover the risks before quoting: no good if you get slapped with an extra bill for additional strengthening or for repair of your roof when it caves in.

Another company offered a warranty without separate insurance backing. They were new to the market with a background in IT. This diversification could, IMHO, be short lived as the FIT's start to drop off - then where would I be?

We took the attitude that the panels would be on our roof at the front and we wouldn't see them. Our house wouldn't win any prizes for beauty so who cares? The more we thought though: why make the house look like a solar array with huge ugly panels slapped all over them? Far better to take a little thought surely? Think carefully about the positioning of the panels both for shading and aesthetics - you may want to sell one day and the house should look reasonable. Who will buy a house that is made as ugly as a stick just to get a FIT?

Think about the loading carefully - it's heavy kit and huge bolts will compromise roof strength.

Think about safety - one company said that scaffolding wasn't needed. Our roof is about 50 degrees and is about 30 feet from top to bottom (chalet house). The thought of installing panels high up using ladders... how does that work? what damage could that do to fragile tiles? I would hate to see an installer tumbling to the ground just because the quote went with a long ladder !

Take up references. yes they could be skewed, but talk to people and try to read between the lines. The references that I have taken have helped me no end to make a decision.

I think I have made my decision. It's with a company that I am happy with. It will cost me more but I am sure that it will be done properly and that the harvest will be a good one. I don't mind paying a bit more because I think I will get a professional installation and decent customer service. Time will tell. I hope I wont be eating these words in six months or six years from now.

Good luck.

 

[Graeme Harrold]

Look for a company that will help you with self consumption of generated electricity, even if its nothing more than altering your electricity usage.

Roof calcs, I will give a cursory glance in the roof space initially, as I always get a surveyor in to do the calcs. Part of my handover pack is a cert stating the roof can support the weight and wind loads. A lot of installers are about to come unstuck over this.

Scaffolding is a MUST even for a bungalow, this would include a suitable mobile platform. Id be wary of anyone who would install from ladders alone.

Micro Inverters. There are still issues with these especially with DNO's. If you are fitting, make sure your DNO will accept them.

Panels should not be positioned closer than 300mm (guidelines) to roof edges, this is mainly due to the wind flow round the edges of structures, however as you mentioned this can also cause problems with water runoff missing guttering. More of a problem with steeper pitch.

For the future, keep an eye out for SUnny Home Manager if you are going for an SMA inverter.

 

[Worcester]

Panels should not be positioned closer than 300mm (guidelines) to roof edges

Hi Graeme, I respect your knowleagable posts, however, I must have missed where that (300mm) is actually written down. We strive for 450mm all round, and if less will significantly increase the number of roof hooks /anchors (decrease the spcaing) at each end of the rails.