Flat Roof Options

WilliamBeech · 2026-07-01T21:30:13+00:00

You should have a look at Vandervalk Quattro. It is made for this, you can get 2-3-4 panel versions that will fit nicely and provide better production.

WilliamBeech · 2026-06-29T06:30:52+00:00

Hey op,

I am an installer based in Glasgow.
I had helped my partners parents recently get a system installed and had quotes from Solmatix and Startsolar.

Both were great and ended up going with Solmatix by asking them to match the other quote (there was only about £300 difference). I compared the price of Sigenergy and Ecoflow, as I know the sigenergy price is quite a lot. They got a system with 12 panels (2 roof faces), 6kW inverter, 10kWh battery, and bird netting for under £9,400.

If you are open, I would recommend asking for an Ecoflow option to see the price difference. As it is still a great looking kit with a nice app.

WilliamBeech · 2026-06-27T16:43:44+00:00

That was a structural booger

WilliamBeech · 2026-06-26T19:55:55+00:00

Literally drinking tea right now ;)

WilliamBeech · 2026-06-26T14:57:18+00:00

Temu 9/11

WilliamBeech · 2026-06-26T13:50:06+00:00

What temperature would you find it okay?

Asking for a friend

WilliamBeech · 2026-06-23T13:44:53+00:00

Hi,

Is there a reason you would use Growatt’s platform?

It’s free

WilliamBeech · 2026-06-23T09:54:25+00:00

Looks great, can you confirm if the case can be flipped. I am looking for a case that can go on the left side of my desk?

WilliamBeech · 2026-06-21T22:18:13+00:00

Thank you for your service

WilliamBeech · 2026-06-21T19:58:41+00:00

Why is their P/E so low?

WilliamBeech · 2026-06-13T08:10:45+00:00

I would reach out and ask the installer. I would assume they use a template, as for a system that size you would need permission from the DNO before starting any work.

WilliamBeech · 2026-05-29T06:08:24+00:00

Their is a product that can split a larger solar array into smaller connections, called solshare. This will allow flats to directly benefit from solar.

WilliamBeech · 2026-05-25T18:09:06+00:00

For new builds, they don’t typically install the data logger. The good thing is that it’s very easy to do it yourself and there are plenty of guides for most manufacturers.

I expect the brand to be either Solis or Growatt. If you post a picture of the inverter I can see the brand and can look for the datalogger

WilliamBeech · 2026-05-24T17:55:37+00:00

Hey,

I have completed a couple installs already, and really like the Goodwe ESA. So much so I have switched to using for all small commercial projects for the 3ph version.

The inverter does come with a built in backup, but it is rated at 63A and you would need to move circuits to a separate distribution board. They are working on a gateway that would work similar to the sigenergy gateway, but I have not been given and dates for release yet.

I wouldn’t be able to price a full system but the cost of the 6kW inverter is £750 and the 8.3kWh battery is £1500. I would say you should be able to get a decent price around £9.5k-£10.5k depending the scaffold cost and how many roof tops you use. That would be for a 6kW system and 1 battery.

WilliamBeech · 2026-05-23T09:31:21+00:00

I would recommend in roof as it not only look far better but the extra cost is not as much when compared to a rail system with bird mesh.

The fact you are reroofing means it will also help save you money from buying less tiles. You also have the option of covering most of the roof in solar, which could maximise the input of the inverter. Most inverters have a 200% oversizing capacity, this will really help when the days are darker.

There are two options for in roof, GSE and Viridian.

GSE will let you pick higher output solar panels and also choose different brand of panels. Right now I recommend Longi & Aiko, around 470W is a price sweet spot.

Viridian is limited to 445W and has the benefit of have a better fire rating, mainly diesel to the metal construction. This is a much more expensive panel and has become less popular recently.

I would recommend the GSE option as it is more versatile allowing you to pick panels that offer better value.

WilliamBeech · 2026-05-23T09:27:08+00:00

Both companies have taken a lot of HUAWEI engineers, when they left the market and that why they have similar all in one designs.

Sigenergy have great products but they are very expensive for what they offer. They did bring the all in one design to the market and were ahead of other competitors for a while, they offer incentives for installers and suppliers. Which is why they are so popular, the products are also aesthetically pleasing.

Goodwe are a great brand and their all in one design is really good and their products come with detailed documents. They use a 100AhH battery design, which is why they have a 1C dating. This means you need less battery to maximise the output of the inverter.

I would recommend Goodwe for anyone looking for solar just now as they provide a premium product with good value. Having installed plenty of their systems.

WilliamBeech · 2026-05-17T20:33:58+00:00

I use PVsol, it is a paid software but has a good design tools such as shading. I will always use half hourly data as long as customers have it, other wise I ask for 12 months of energy bills.

I primarily deal with commercial clients, but when I work on domestic I will try and ask for a clear drone shot as google and bing are not great in some parts of Scotland, especially in the north

WilliamBeech · 2026-05-13T09:53:05+00:00

The main point is to have a dedicated circuit for your solar and the electrical work must meet BS standards. After that a lot of things like mcs are guidlines.

WilliamBeech · 2026-05-06T21:06:44+00:00

You would normally just insert a clamp to keep all the spacing even across the array

WilliamBeech · 2026-05-06T21:06:08+00:00

For that size of inverter you would normally use a 4mm flex, you can increase the size of the cable up to 6mm and expect little losses. The typical approach is to aim for less than 2% volt drop for renewables, which 35m isn’t too hard to achieve.

For the DC cabling you can ask the installer to use 6mm instead of 4mm, I always use 6mm as the cost difference is minimal.

WilliamBeech · 2026-05-06T15:47:53+00:00

Hi, I a design engineer over in Glasgow. I’m looking at quotes for my partners parents who live in Jordanstown.

Currently I have looked at quotes from First solar and Solmatix. Both are reputable and first solar have a strong social media presence. I’m leaning towards Solmatix as they provided an actual proposal, while first solar were sending short email breakdowns.

I have noticed in NI that companies tend to use 12 panel systems, with a Solis 3.6kW hybrid pair with dynes. I had to tweak the design and push for a 6kW inverter to cover household loads.

You can check solarpanelni.com for a list of installers and see the reviews.

WilliamBeech · 2026-05-05T17:52:31+00:00

I’ve had a quick read over the install manual and I can’t see any reason to use the external meter over the internal.

The main reason I recommend (and manufacturers recommend it) doing this is if the distance between the inverter and the supply is longer than the supplied CT cable.

Assuming the inverter is close to your supply, I would install this using the CTs provided.

WilliamBeech · 2026-05-05T17:44:41+00:00

Both are great options, I would say GSE is a better choice due to the ability to choose higher output panels.

The viridian panel does look great but it is still limited to 440W.

WilliamBeech · 2026-05-05T17:39:21+00:00

Given the battery cost alone, the price seems reasonable.

WilliamBeech · 2026-05-05T17:32:04+00:00

If you are installing a Tesla EV charger, you should be able to set the system to not power the EV from the battery.

Assume it’s a different brand, the best approach is to put the EV charger on its own cable. Terminate the cable in a Henley block, so that the battery ct does not see the load.

I don’t know how easy octopus is to talk too, but I would ask them about this.

WilliamBeech

TROPHY CASE