Costs of building a solar powered gateway

Hi
I’m a total newbie and just been playing with Meshtastic so far, but, I think TheThings is maybe what I really want to play with.
But the problem is that I don’t think I’ll be able to reliably hit a community TheThings gateway from here.
So maybe I should build one.
I live in a reasonably flat bit of London and because we have a loft conversion there’s a flat roof that I can easily access right at the top of the house. I could just sit it on the roof and bolt an antenna to the existing TV antenna pole.
However I don’t really want to punch holes in my house to run power up there.
So I’m thinking maybe build a pi / iC880a and put it in a water proof plastic box up there? I have a spare car battery sitting around so maybe power it from that with a solar panel? There is already a WiFi AP in the loft so it could connect to the that.
I’m wondering what kind of solar panel I’m going to need and how much it would cost? London is often cloudy and doesn’t get a lot of sun during the winter.

A side question. Is it (even theoretically) possible for a TheThings gateway to also, and simultaneously, be a Meshtastic node? running both stacks in parallel?

thanks

Dealing with that first then we can ignore from here on as this is Forum for LoRaWAN and for the Things Network - paid for by TTI. Short answer NO!

Amongst Many issues and practicalities that would need to be overcome bottom line is all radiators are subject to duty cycle constraints - especially if this is London UK! Two ‘networks’ with no knowledge of what the other is doing, could potentially command the GW to transmit more frequenty that is permitted. Plus network traffic could clash - who takes priority - or be lost (GW deaf when Txing). You need to learn more on nature and behaviour of a LoRaWAN network and its architecture - check out the documentation and the Learn section.

Much of London and surrounding area is covered by TTN associated GW’s - directly or private networks peering via e.g. Packet Broker, so YMMV wrt coverage by the community network. Where are you? If London UK (BT IP?) easy to discuss, if London Ontario or where ever! :wink: may be more challenged :man_shrugging:

Solar works fine in UK, despite the weather. How well will depend on what you are expecting and how well specified, where placed (if on open roof top with good view of sky through the day you should be good to go), and the consumption of the kit.

Some deployments running on lower power kit and a decent battery get away with 50/60W panels allowing for occasional drop off if long period or poor weather/snow accumulation during winter months, others with 100/120W/150W panels and higher battery back up capacity happily run 24/7/365, some even with slightly impaired sky views (trees - issue declines in winter as they shed leaves so problems somewhat mitigated.) Modern panels generate quite well even when sun behind light cloud - direct sunlight not always needed. An ethernet cable - delivering PoE solves a lot of problems. If you must use wireless connection then go low power setting on Wifi if AP is in close proximity in the loft as often lower power consumption that say 3/4/5G Cellular, and on that subject for a basic GW running off solar a unit based on a Pi0W, using wifi is a more realistic choice than a Pi4/5 with 8GRAM! :wink:

Of course a good 1st step - especially whilst learning and familiarising is get a basic, low cost GW and put it in your loft, sheltered and run from internal power… should be good enough for you own in house developments and will also add to the Community coverage (how well will depend on the roof construction and mounting arrangements).

Looks like a good item for the labs …

Rarely is size so important, what would you recommend for the battery capacity?

Leaving aside the above comment about this being LoRaWAN only, there is the no small problem of using a concentrator card as a standard LoRa radio and if you could do that, there’s the multitasking issue for the concentrator card which was never designed for that.

In summary, apart from the law, physics, wrong forum, electronics design, RF issues, multitasking, aquaducts, sanitation, the roads, viniculture, it would be so much simpler to get a T-Beam to do the job for you and leave the gateway to do it’s thing - if it’s on TTN, we like our gateways stable, I cannot lie.

Another of those piece of string questions - it all depends! If site isnt compromised and gets full sun view dusk till dawn and looking to cover say 1 day of really bad weather/snow cover on panel or whatever then low power design can accomodate say a 25/30Ah battery if used with a MPPT controller & 60W panel. If looking to cover say 3 days bad weather/snow coverage etc. (Not uncommon in uk!) then I would look to 70-90Ah battery with 100-120W in south of England increasing to 120-150W with 85-110Ah Battery in Northern England or Scotland! If budget allows I go AGM on battery with MPPT Solar controller where I can. If budget an issue and confident on available core power I may drop to one of the cheap none MPPT’s out of China (often used by camping or river/canal boating fraturnity) - min 10, usually 12/15A rated. Mileage and objectives will vary wrt costs. Have done ‘expensive’ rigs with core costing >~£500 (Victron Energy Controllers, & Big Panels, plus premium batteries & comprehensive LoRaWAN based monitoring/battery switching) that have performed brilliantly over several years, others that had niggley problems that took forever to settle and be optimised/reliable, but also run cheap kit - dual 30W panels cheap controllers, recycled car batteries that were >3 years old, that came in aro £100 and worked a treat! (Within expectations that is :wink: ). Note having 2 panels is another useful hack as even when not optimised for peak sun most modern panels good at sourcing power if sky open and clear, so that allows for pointing 1 slightly towards east so catches sun early and starts contributing/running just as battery likely at lowest ebb from overnight run. On one rig with panel optimised for good winter peak sun it was found system dropped out occasionally around winter dawn. Angling a panel to catch early rays made difference and acted as keep alive until full sun up, saving need for plan B which was to go up quite a bit on battery and poss increase panel by 25%! Another hack is some cheap controllers have 1 or 2 USB outlets on them - useful for fully off grid deployments…just add a 3G/4G dongle/mi-fi device of your choice, slap in a sim, allow an extra bit of headroom on power budget and Bob’s your mothers brother, with a cellular enabled off grid GW deployment!

Easy build is to use scaffolding or an exercise/pull bars rig as housing for all kit with GW ant on pole off top or easier yet a decent (pref wide bottom tread for lateral stability) step ladder, with 2 x panels mounted vertically above each other, poss with top panel angled 10-20deg towards dawn horizon as above, the heavy kit (battery/batteries), poss main GW electronics, some additional ballast on lowest step(s) or even shetered in core of ladder structucture to give stability especially from lateral strong winds. By chance panel angle often then quite well optimised for winter sun maximum power (will depend on site latitude of course), padding panel angel with some wooden battening if needed.

I’m in London, England; specifically Ruislip.
The nearest gateway appears to be 4 or 5km away at Uxbridge University.

I was thinking about the “dual stack” thing and I guess one difference as I understand it is that a Meshtastic node has the entire point to point LoRa stack whereas I think that a TTN gateway is only terminating some of the stack an trucking it off over the Internet. I don’t think that an iC880a can even do Meshtastic. So that was a silly question on my part.

A LoRaWAN gateway is listening on 8 channels over 6 spreading factors at the same time - as it doesn’t hold the encryption keys for potentially tens of thousands of local devices, sure, it “trucks it off over the internet”.

As implied above, a gateway concentrator card could do Meshtastic if it was programmed appropriately but it would be overkill.

The underlying radio technology is LoRa but that doesn’t mean you can compare LoRaWAN to Meshtastic, they are designed to do different jobs at different scales appropriate for use. For LoRaWAN the LoRa provides the Long Range & low power, mostly the actual radio hardware is just another chip on the board and the configuration of a new sensor device can be done in a minute. It’s when you have 100 or more sensors that LoRaWAN starts to yield benefits.

Meshtastic support recently said they have no interest in ‘integrating’ nodes with LoRaWAN.

The cheapest 100w solar kits seem to be about £70. Maybe I should just buy a long reel of cable and run it from the flat roof to the garage at the end of the garden where I already have power. Drilling holes in the garage doesn’t worry me so much as the house.

I’d be the opposite - running long reels of cable outside with mains vs drilling hole in to the paper mache (that passes for plasterboard these days) ceiling that you can probably poke with a sharp enough pencil

Also, you’ve just spend a few quid on a iC880a and a Pi - in the LoRaWAN world £70 isn’t a huge investment.

actually I thought of a better solution.
There is a chimney stack going up to the roof which has a balanced flue for the gas heating boiler.
I could drill a hole in the side of the chimney (on the roof) and poke a cable inside the chimney and it run down next to the flue and pop out where the boiler is, which also has a 240V power socket.

There’s a two part series video demonstrating how to do a DIY solar powered LoRaWAN gateway, but for London I’m guesstimating you’d need at least 100W solar panel for those rainy winter seasons.

pt1. https://youtu.be/NickTQ-uNQw?si=L0AT1q_-jR7FKVtC
pt2. https://youtu.be/j8fSeLkmfHA?si=wMdarp5jrwxuxPuz