Raspberry Pi OS (64-bit) , for farming, and more

I user to work for an Internet Provider. We used battery backups on many sites, one place was combined with solar. Lead acid batteries used for backup power supplies are very similar to those used in cars. Only safety concerns are burning wires from short circuits or overcurrent (put fuse on wire going from battery) and the place with battery should be vented (lead batteries generate hydrogen if overcharged).
As for how long the battery survives, it depends on temperature (10˚C ideal) and how deep are the cycles. Cycling 60-100% charge will make the battery last 10 times longer than 20-100%. I mentioned the car battery mainly because you can have it for free sometimes. As they get old they are not able to deliver enough amps to start a car, but when discharged slowly they can still have enough capacity to be usable.
I agree that when buying new, it is probably better to go LiFePO4 with todays prices.

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A backup supply is rarely used and kept fully charged all the time, which is the perfect application for lead acid - never discharge!

This is not true from my study or experience. Lead acid batteries last longer (more cycles) the smaller the amount of discharge. One way to look at it is that there’s a maximum amount of energy that can be stored and discharged over the total uses and recharges for a given battery. So every time you use the battery some of that maximum is ‘used up’.

Specialist deep cycle batteries can typically handle up to 50% discharge maximum, providing they are fully recharged every time, but that maximum will reduce slowly over the life of the battery. Any lead acid battery will be damaged (lose capacity) if not fully recharged frequently (which can take several hours depending on how far it is discharged). I used deep cycle batteries and made them last seven years in a daily cycle, which were fully recharged at least once per week, and to above 90% almost every other day. Typical car/starter batteries wouldn’t survive this for long because they have less useable capacity to start with, so as capacity is lost they become unusable after fewer cycles.

You can get data sheets online which show you battery life (in terms of discharge/recharge cycles) and how this varies with depth of discharge. There’s a pretty much linear relationship (higher discharge/fewer cycles), but if you don’t fully recharge you will permanently lose capacity because the plates acquire sulphide deposits that quickly become permanent reducing the active surface area of the plates. Some of that can be reclaimed with a higher voltage charge if you don’t wait to long. Charts from manufacturers assume a full recharge after every discharge (so they ignore the effects of sulphation due to incomplete charging). This makes it hard to achieve the full ‘expected’ lifetime unless you can use a constant charging source like mains.

A typical car/starter battery is only discharged a couple of percent for a normally engine start and then recharged immediately during the journey and then kept topped up. Run it too low and you will lose some capacity because you probably won’t run the engine long enough for a full recharge afterwards, but it will still have enough to perform normal engine starts so it will still be useable even if you do this several times. It may not have enough to start a damp cold engine in the middle of winter though!

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you could have the modem/router on battery because it can work without electricity

It is probably confusing as I wrote it, we agree on this.

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Yes I misread your example and have corrected my response. Sorry about that!

Our internet connection lasts about 15 to 30 minutes if a blackout occurs. The nodes in the pits only have that much backup power. They do this because a blackout does not necessarily affect the whole area that the node supplies.

I’m interested in reading your full braindump to see how to start farming, but the link tells me that the post is private or does not exist.

Is there somewhere that explains how to compile a node and get it running? I went to the github page, but there are 50 different repos there and I don’t understand which ones I should be looking at.

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safe network is not live yet, we got some alpha nodes and testnets and you can join following the instructions in each testnet thread (comnet, sjefolaht, dreamnet etc)

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You don’t have to compile, but if you did the repo you need is safe_network, get Rust and then cargo build --release and the node will be target/release/sn_node. The repo may have some help in the README but I haven’t checked.

But you can skip all that and just install the release using instructions given with a test network.

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Has anyone managed to coax a Pi to run an 11 node baby-fleming?

I know its pointless and would mean nothing in production but I’m still curious …

This isn’t helping answer your question but what is the significance of 11 nodes? Is it the number in theory that could run on a Pi because of the amount of RAM? Is it the minimum needed to run a network?

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11 is the default no of nodes created when you run baby-fleming. 7 elders and 4 adults.
I think of it of the minimum needed to create a viable section on your own box.
You can change this with the --nodes flag

Thanks. That does make sense then. I don’t know much about the requirements for running nodes but there will always be a bottleneck somewhere whether it is CPU, memory bandwidth, disk IO and with something as small as a PI I think something will be hit. But it sounds like a noble endeavour!

Each ant in a colony is weak and defenceless on its own but when working together the colony is a wonder to behold.

We are going for the same thing here but in the digital world!!

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