Fitting Solar Panels to House Wall

[@gcbus2]

In addition to my roof mounted (45 degrees) SouthEast facing three x 235W panels (shaded at times) and seven x 330W panels (not shaded), I've just had a vertically wall mounted south facing 365W panel installed - it'll be interesting to see how it performs - it won't be shaded. All panels have Enphase microinverters. The new panel is looking good so far :-)

[@Nigel_Broatch]

Are your inverters the grid-tie type? Mine are, they have a high minimum voltage input so I have to connect about 5 panels in series to make them work.

[@gcbus2]

@@Nigel_Broatch Yes as required by law - as there is one per panel they are independent of each other too.

[@witengineer6377]

I'm doing the same thing on the south facing side of my house with a goal of 2,000 watts!

[@Nigel_Broatch]

Sounds good. This wall faces South-west which is OK. The problem I have here, with trying to catch the sun when it's low, are neighbour's trees in the way. Additionally with the panels not being all that high. Most solar panels would be mounted on the roof but I already have thermal panels up there (for hot water ). Luckily neighbouring houses, although lower than the trees, are far enough away not to matter. The sun is too low and weak by the time the houses shade the panels.

[@catalinc5890]

Cheers ! very good work indeed ! I am searching for a simple non-expensive way mount a string of panels just like you did here, wall mounted and vertically. What did you use to mount them ? Can you please give me some details ? Did you drill holes in the aluminium of the panel ? Thank you so much ?

[@Nigel_Broatch]

Use L shaped galvanized steel pieces that are normally used for constructing fences, they are very thick and strong and come with 8mm holes in the 2 sides. Bolt them to the wall using 8mm bolts into metal expanding wall fixings. I used a short piece of Dexion between panel and the L piece. Drill an 8mm hole in the frame of the panel, one at each of the top corners, bolt together with 8mm bolts and nyloc nuts (don't tighten hard, the frame is soft and double layer, easily squashed). The rules in UK appear to be that solar panels mustn't stick out from the wall more than 200mm, I held mine out at the bottom using 2 metal L strips, measuring 25mm on the longer edge. Fix with a self tapping screw. It's hard to describe but I hope it makes sense by pausing the video and looking closely at it. It's probably a good idea to earth all the panels in case something goes wrong as collectively they generate several 100 volts DC which is more dangerous than AC for a given voltage. Connect in series, calculate both the total off-load voltage (Voc) and total power (watts) and chose a grid-tie inverter (or whatever you are connecting them to) that can handle that power and voltage. A grid-tie inverter also has a minimum input voltage, so if only connecting a few panels in series make sure the inverter (or whatever) will work at that low voltage, use the max power voltage (Vmpp) specified on the panels to calculate this (on another setup I had 5 panels in series, which wasn't enough voltage to use with a particular grid-tie inverter which needed over 150V DC to work).

[@catalinc5890]

@@Nigel_Broatch Thank you so much or your answer an the detailed response ! you detailed very well, it's very helpfull ! I do appreciate it ! i am allready offgrid with 12 kw of storage and i definetly agree about earthing the panels in the case of anything happening. Another question, if you would be able to distance the panels more from the walls - to have the space behind the panel and the wall behind a larger space for cooling and some airflow circulation - what solution would you use ?

[@Nigel_Broatch]

@@catalinc5890 I haven't thought about that. I don't think they need more air flow behind as there's a 20 cm gap at the bottom. I have wondered if they'd get more sunlight if they were angled at 45 degrees but they face south-west anyway, which isn't too bad for most of the year (I'm in the south of England). Wind is likely to be a problem if mounted further out from the wall. An improvement would be to lower them by about 30 cm, because the overhang of the roof causes a shadow for an hour or so each day around June - July. Although that would only be of significant benefit if I had battery storage or a feed-in tariff, because when the sun is that high my other panels give plenty of power anyway (often "wasting" over 1kW into the grid).

[@super-sim1665]

How much power?

[@Nigel_Broatch]

This array has 5 panels at 255W each, so a theoretical total of 1.275kW. I think I have had over 1kW out of them but have never noted the readings down anywhere. 800kW at least. I have 3 more solar arrays so it's easy to forget the readings. The only notes I record are the total energy kWh each year, taken in December. This array was: year 2017 - 703kWh, year 2018 - 654kWh, year 2019 - 588kWh. The energy has gone down due to neighbour's trees growing, shading the panel on the end.

[@super-sim1665]

@@Nigel_Broatch Thanks. Good to know it's difficult to get information on output at different angles. I've noticed almost 50% loss on flat mount so this looks better.

[@Nigel_Broatch]

@@super-sim1665 some basic tests that I did showed that in very cloudy weather the panels get most energy when flat. When there's direct sunlight the panels get most when pointing directly at the sun.

[@schlepers]

Thanks for making vid. Im thinking of putting vertical 5 or 6 320 watt panels on the side of my pad too. But there is some shade from the roof hang. So, I guess it can drop 50% or so...??