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maintenance

compost is running with the aid of an external battery since yesterday. This is the second time that the energy provided by the panel was so little that we needed some help to keep things running. Berlin's Octobers are so grey that it's just not enough.

Taking the battery upstairs still makes it a very heedful act. There is actual, physical stuff involved in keeping things running, and labor and attention. The battery pack weighs a couple hundred grams and there are fourty steps to go upstairs to the attic. And even though everything is lying in place almost unmoved you can clearly see physical wear and tear: The once navy-colored fabric of the solar panel is fading more and more from the sun exposure, first into a bright and pale lilac shade and now into grey, and the rubber band is starting to tear from being wedged into the window frame, the inner rubber strings clearly visible.

The forecast for the next couple of days predicts two to three hours of sunlight each day, let's see how much of that we can catch.

Photo of a phone next to a rectangular battery pack with rounded corners. Both are placed on top of parallel, slightly glossy pieces of wood running from top to bottom of the picture frame.A shot taken from inside, looking out of a window. The focus is on the window frame with the background appearing blurry. Wedged into the window frame is a damaged rubber band that has its insides curling out like soft spaghetti.

Hi there! compost.party is back online after being quiet for several days.

We did not establish clearly who would take care of it while some were travelling. Those who tried to take care were hampered by the broken screen providing little feedback about what is happening — even less so if you cannot interpret the intermittent rows of colorful pixels from prior experience.

Like the previous outages the reasons can be found in beyond-technical, social and communicative issues. The fact that the weather is changing with the seasons trips up the intuition, but right now, on a windy, clouded but bright autumn day with 14°C, the solar panel delivers a comfortable 450 mA of energy, out of which 380 mA go straight into the battery, so the hardware is still happily up to it.

We'll continue to figure things out and adjust.

Photo of a linden treetop, shot with the camera pointing upwards from closely below the canopy. You see mostly leaves, and a homogenous cloudy sky in the background.

Nothing out of the ordinary. still that regular small motion required to keep things running. walking up the stairs, grabbing the key, and walking further up the stairs to open a door that's been here longer than any other inhabitant.

The days are getting shorter, you can see it's already getting dark around 20:30 here. Just a couple of weeks ago it was 21:00. It's very unclear how things will continue to run once the sun will set at 16:00.

The daily average sunshine duration in December is roughly an hour. That probably won't be enough to keep it going through the entire winter.

But before winter comes fall, and as long as it lasts it's still plenty warm around here.

A photo shows a small bicycle and a sled. A phone is lying on the sled, and the inside of a ceiling, hung with plastic covering, is slightly visible in the background. Light is shining in from outside the photo's frame.

Just taking a little moment to appreciate that our neighbors were kind enough to reset the charging status by pulling the power cord and plugging it back in for the past two days to allow for some travelling and other things.

compost was offline again this morning, network issues caused it to not be reachable for a while.

Not calling anyone (or anything) out, simply stating facts and saying that it was the repeater (again). Wifi access in general is probably the single thing causing the most issues, ever since starting to prepare compost for the wider world.

The repeater really helps. It helps because the attic is too far away from the main modem / router, and without the repeater there would be no wifi coverage to speak of at all. So the extra device is located on top of a cupboard (shelf?) in the neighbors' kitchen, almost exactly halfway between compost and the router. An Archer C7 v2, old enough to remember several different flats, running OpenWRT – notably another project run mostly by volunteers, keeping hardware running way beyond profitability.

And so this morning the repeater was gone from the network, frunreachable all of a sudden. Our neighbors needed their time to wake up, have breakfast and get their child to the nursery. When knocking later they couldn't open because a call they had while working from home didn't allow it.

As soon as we had physical access, the (temporary) fix was to connect an ethernet cable to the repeater, entering wifi into the prompt and hitting enter. Voila.

Unfortunately compost itself didn't reconnect, so it had to be physically rebooted, interrupting the one and a half month streak. This added a bitter taste to the daily ritual of unplugging and replugging the power cable.

The longer fix will require a deeper inspection of OpenWRT's wifi settings. They can be intimidating, and so it's something that you'd rather try to avoid. The root issue seems to be experienced by other people as well, that's at least something.

A picture of a kitchen counter. You can see a sink and some dishes, and next to it a laptop. The laptop is connected via eithernet, and the cable spirals up upwards out of the picture.

There was a brief offline period starting today at 10:00. It's a bit intimidating to find that a device on your netowrk is not responding anymore even though you know that it is running. Maybe there was some software issue that went unpatched for too long?

Luckily the device responded when it was connected with a USB cable. This error message was shown when trying to establish the wifi connection:

Error: Connection activation failed: IP configuration could not be reserved (no available address, timeout, etc.)

It first appeared to be an issue with the wifi drivers, but investigating this did not turn up anything useful. Restarting the wifi repeater worked.

The repeater is an old Archer C7 running OpenWRT. It's unclear why it stopped forwarding the DHCP requests, but it's also not super important at the moment.

Albeit it wasn't always reachable (with the soda and all), compost has been humming happily for more than 40 days now.

 13:36:39 up 43 days,  2:58,  0 users,  load average: 0.00, 0.02, 0.00

Compost.party was offline for roughly 30 minutes today because a bottle of fermented soda exploded in the kitchen and blew a fuse.

Every guide warns you about this: A lot of pressure can build up during the fermentation process and if you're using bottles that aren't stable enough they can will explode. And exactly that ends up happening.

Some of the liquid dripped into a power plug which popped a fuse and shut down all electrical devices. For the time it took to clean up the mess and restart everything, this here was offline. The phone itself was not affected, but the modem and router were, and because of the way things are currently set up, there was no connection to the internet.

Apologies for any inconvenience! :)

A mess! A countertop with a broken bottle, liquid, a cloth, a knife and many other small things

You'd think you develop a good feeling for this, but it remains surprising just how little energy is needed to keep this phone running.

There are two ways you can get an intuition for the amount of energy the solar panel will generate: First there's the sky, but it has been misleading in the past. Even when it's cloudy, the rays that get through can be enough to keep the light on.

Then there's the ground and the shadows tell an interesting story: If they are dark and crisp, the sun is shining in front of a blue sky, providing ideal conditions. If they are dark and blurry it means clouds overhead, but they still let a lot of light through. Today they are barely visible, a light grey blur, and it's still more than enough for the panel to generate 1.2 W and slowly charge the battery again.

We still have the issue of the charger not picking up again after a thicker cloud covered the sun, but it appears on different SDM845 devices as well, so there's hope that this can be fixed with some driver modifications.

A photograph of a building wall through a treetop.

Updated some packages:

sudo apk update
apk list --upgradable # check changes
sudo apk upgrade

compost started its life on postmarketOS edge, which uses the Alpine Linux edge repositories, but has since been moved to v24.06 and Alpine Linux 3.20 to avoid being surprised by breaking changes. This round of updates included minor changes to go, gojq & restic, as well as some changes to Mozilla's CA certificates.

Oops, still no luck with the fallback option to open the attic door.

The charging cable still needs to be unplugged and replugged daily. It's not clear if there's something wrong with the panel (happens with two different ones), or if it's the charging driver, but the usual sequence is this: The sun is shining, everything's nice and there's a current of about 1 A. The sun disappears, as it does, and once it comes back, the current doesn't return. Instead, no matter how strong the sun, there's a current of only 36.8 mA. The only way to start charging again is to physically unplug the cable and plug it back in. I'm tempted to blow air into the plug every single time.

To get enough sun we asked the neighbors if we could hang the panel out of their south-facing attic window. They find this whole setup a bit weird and asked me whether this is some dark web operation, but overall they take it kindly. Still, sometimes it feels like a bother to them, and to make it a bit easier for all of us I tried to get some tool to open the lock that's probably a century old. Unfortunately I cheaped out and the wire it was made from quickly twisted.

Honestly the chitchat with the neighbors isn't so bad after all.

A wire in that was cleanly bent into the shape of a key is warped and out of shape

The sky is still mostly covered in clouds, but some rays make it through and sometimes provide a bit of charge:

[Jul 03 13:15:00] {"pmi8998-charger":{"status":"Discharging","current":{"value":0.0,"unit":"mA"},"voltage":{"value":0.0,"unit":"V"},"consumption":{"value":0.0,"unit":"W"}},"qcom-battery":{"capacity":{"value":58,"unit":"%"},"status":"Discharging","current":{"value":42.0,"unit":"mA"},"voltage":{"value":3.9,"unit":"V"},"consumption":{"value":0.2,"unit":"W"}}}
[Jul 03 13:30:00] {"pmi8998-charger":{"status":"Charging","current":{"value":1095.9,"unit":"mA"},"voltage":{"value":3.8,"unit":"V"},"consumption":{"value":4.2,"unit":"W"}},"qcom-battery":{"capacity":{"value":59,"unit":"%"},"status":"Charging","current":{"value":58.6,"unit":"mA"},"voltage":{"value":3.9,"unit":"V"},"consumption":{"value":0.2,"unit":"W"}}}
[Jul 03 13:45:00] {"pmi8998-charger":{"status":"Charging","current":{"value":782.8,"unit":"mA"},"voltage":{"value":3.8,"unit":"V"},"consumption":{"value":3.0,"unit":"W"}},"qcom-battery":{"capacity":{"value":59,"unit":"%"},"status":"Charging","current":{"value":55.2,"unit":"mA"},"voltage":{"value":3.9,"unit":"V"},"consumption":{"value":0.2,"unit":"W"}}}
[Jul 03 14:00:00] {"pmi8998-charger":{"status":"Charging","current":{"value":9.2,"unit":"mA"},"voltage":{"value":4.0,"unit":"V"},"consumption":{"value":0.0,"unit":"W"}},"qcom-battery":{"capacity":{"value":59,"unit":"%"},"status":"Charging","current":{"value":47.4,"unit":"mA"},"voltage":{"value":3.9,"unit":"V"},"consumption":{"value":0.2,"unit":"W"}}}
Picture of a cloudy sky

Compost was offline for the past several days.

Current issues with the charger require the phone's cable to be unplugged and plugged back in approximately once a day. Our neighbors were on vacation and unfortunately took the keys to the attic with them, so the battery ran out some time last Saturday.

Now that our neighbors are back after a lovely weekend we again have access to the key. Since today is a very cloudy day, the phone is given some initial charge from a power bank that still has some juice from when the sun was shining more brightly. Maybe some light lockpicking skills will help avoid similar problems in the future.

A phone on the ground is connected to a plastic block with a USB cableA look outside a window at roof level, showing a cloudy sky above a building

battery level

99%