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Where I live, a small area is served by the municipal electric service. That is, the town runs it. They maintain the lines, and bill me for power. They are dependent on the local big commercial utility to actually connect to the grid, but they bid on power separately. As a result my electricity is very cheap, around US $0.05/kWh. About once a year they send out a statement listing the sources they buy power from, almost completely nuclear and hydro.

It's reliable, too. The power does flicker now and then, I'd say at least three or four times a year. This is an outage of a couple seconds or more, not long but enough to reset clocks etc. (Regardless of how reliable your electric is, having a UPS for computers and other sensitive stuff is still a good idea.) More rare is an outage lasting a couple hours, but it does happen. We get wind or other storms now and then. One outage of this duration a year might be about right, but it might be more like one every year and a half.

The worst outage I can remember lasted a day and a half, back in 2021. That was the result of a big spring storm. We had snow on the ground, and while it did melt during the day it got cold. I have natural gas for heat, but the controls are electric, and I didn't have an easy way to switch them over to inverter power. I still don't, it's on the list.

Overall I'm pretty happy with this. Sure, it's a small area they serve, but they do a good job. Other town residents seem to be pretty happy with it as well. I just find it interesting, because it's a decent example of government doing something right. There are a lot of factors when you look at it, like it being a smaller town with a more manageable area and engaged residents, and as I mentioned a feed from the local commercial utility. But, my taxes aren't too bad, and electric service tends to be a natural monopoly.

Meanwhile, I've been waiting for a second wired internet option. There's a small company building out fiber, but they haven't reached my area yet. I have cable now, which actually works well, but I'd love the additional upload. Some areas have done municipal broadband, with great success. But then big telecom companies lobby, and all of a sudden the 'government will screw it up' idea looms in the air.

It seems like if people give a damn, and are willing to hold the town's feet to the fire, municipal services like this can work great. Not that there's never a place for private services, but we shouldn't take the idea that municipal=bad as the gospel truth.

It's been a while since I've shouted into this void.

Routine is interesting. It's comforting, stabilizing, reliable. But it's also repetitive, constant, possibly boring. I look forward to it to some degree each day, worry when deviating from it, and look forward to it if I've been away from it. But then again, I also kind of resent it.

I'm not sure where I'm going with this, other than the observation that the weeks just seem to be flying by quicker and quicker. Things in my life have been decent lately, but there's a lot of shit out in the world right now. And I wonder if I should be doing something different.

Over the years of accumulating renewable energy-related gear, I've evolved several variations of the battery-in-a-box concept. Basically, some sort of portable system with a battery and a charge controller, and other wiring, to be used with solar panels as the primary charging source, for powering whatever. That could include charging electronics, running amateur radio stuff, etc.

In the past I've hard several of these sorts of systems I could grab, usually a smaller one and a larger one. And, enough other crap to throw one or two more together. Right now, I've settled on having a larger more permanent system, which lives in my basement. It's got a 105 Ah AGM battery, charged by 164 watts (nameplate) of solar from three old panels. I might see 10 A into the battery on a sunny day if I've discharged it, but it's a non-useless amount of power – I've run lighting and laptops with it during power outages, for instance, and shift some loads to it on sunny days such as fans.

The recent portable system, however, has a 50 Ah LiFePO4 battery, and a couple of 130 watt semi-flexible photovoltaic panels. (The panels and battery are from Eco-Worthy, and the charge controller is a Morningstar SunSaver MPPT, of which there is another in the previous system I mentioned.) This is technically more powerful, with a little less storage than the permanent system. (Technically you can better utilize the LiFePO4 battery compared to lead acid, but it does work out being a little less capacity.) It's great for ham radio, backup power, etc., and excels of course when the sun is shining – if you have loads you want to run during the day, it's great.

I do have a mishmash of solar panels and batteries, not all of which are used, but I definitely have more smaller batteries sitting around. Sometimes it's nice to be able to grab one for something, and I rotate them for charging. Usually, I do this by putting them in parallel with a battery in one of the other two systems. It's not the most careful way of charging, but if you keep an eye on it, it works. As long as you don't have something set up for an absurdly high charging voltage, like if you wanted to equalize a flooded lead acid battery, you don't really damage anything.

Example: 4 Ah Gel Cell

I have a small gel cell, about 4 Ah, as kind of a lab bench battery. If I parallel it with the big system, with the 105 Ah AGM battery, it might see 14.3 V when that system is in Absorb (meaning, the charge controller is letting the battery sit at constant voltage). That's not too bad, and with wiring drop the smaller battery might pull a quarter of an amp from the bigger system, more if it's more discharged.

Example: Car Charging

I have a cord I made with a power diode in series on the positive side. It has Anderson PowerPoles on both ends, and I also have a cigarette light cord I made with PowerPoles. This actually works out for charging any of these batteries in the car, since the diode introduces a drop of about 0.4 V, and when the car is running the alternator can get up to 14.8 V or so based on my observations. (Actually, this is a guess, I've measured about 14.3 V after the diode while the car is running.) The diode not only keeps the battery from discharging, it also sort of keeps the car from being powered when it's off. This is because I don't really know how it's shutting the cigarette lighter outlet off, I assume it's a relay, but I don't know what else is on that circuit.

This works great for portable radio applications. You just go cigarette lighter –> fuse –> diode –> fuse –> battery –> fuse –> radio. When fusing, keep in mind where energy might come from in the event of a short. For instance, a short in between the diode and battery means current could dump in from both the car and the smaller battery.

Battery To Battery Charger

There are commercial DC-DC chargers out there, and constructing one of my own is on my list. The advantage here is a) having a proper charging algorithm for your battery, and b) being able to charge even if the source battery is at a slightly lower voltage.

That said, this is more complex, and sometimes simplicity is more the way to go. The DC-DC charger is a good idea in something like a camper, however.

So, now for some solid requirements about my solar-powered Raspberry Pi project. To recap, the idea is to have a Pi hosting a small, static website, while powered by just a solar panel with minimal storage. Enough storage to keep it running if a cloud passes over, and to allow the Pi to gracefully boot up and shut down. This Pi would also act as a 'regular' Linux server, that you could SSH into and do stuff on. In other words, not just an appliance with a read-only file system.

Super capacitors make sense here. One of the goals is to avoid using a battery, and a capacitor should have a long lifespan. The current plan is to charge a cap bank with a solar panel, and have that feed the Pi via a linear regulator. Wasteful, but at the same time simple.

I spent some time looking into the Pi's GPIO, in terms of booting up and shutting down. The idea would be something like this:

• Sun comes up, panel begins charging cap bank.
• Cap bank hits Vmin, which turns on enable pin on linear regulator.
• Cap bank hits designated high voltage, Vmax, somewhere between the panel's max power voltage (Vmp) and open circuit voltage (Voc). This boots the Pi via GPIO.
• The panel presumably puts out more current than the Pi consumes, so this stays running for a while.
• The voltage begins to drop due to overcast conditions or, you know, nighttime.
  
• The cap hits the shutdown voltage (Vsht_dn), which signals the Pi to shut down. This also starts a 1 minute timer.
  • The voltage begins to rise again, because the cloud blew over.
    • After the timer expires, the Pi can be booted again via GPIO, if it hits Vmax.
  • The voltage continues to fall, because it's night.
    
    • The cap is sized so that there's a delay of about 1 minute before the Pi drains it to Vmin, at which point the linear regulator is disabled. This keeps low voltage from damaging the Pi.

This is fairly straightforward, just required some thinking on edge cases. And, some logic stuff I'll have to sort out, but that shouldn't be too bad.

So I'm realizing that I kind of like using this as a blogging platform. I want to develop my web site a little, and have a Wordpress blog I use there, but have been thinking about switching to something static-based. And/or using this more. A lot of it is that I need to think about what I really want it to be, and sit down and actually work on it.

I'm kind of thinking that this is a nice place for stream-of-consciousness, generally updates about life. It's a natural extension from posting about stuff on the Fediverse, but still accessible for those not on it. Really, the comments are one of the things that I kind of wonder if I'd miss from giving up Wordpress. It was nice to get one once in a while, but there was also a lot of spam. Plus, email is a thing. In the old days of the web, people set up small personal sites, and maybe publish emails they received there. That could be automated a little, but something like that?

Some sort of scheme to accept comment via email and publish them as updates to static site? Might be interesting.

In the mean time, I just stick a Fedi account as part of the signature here, and get pinged when this actually federates. And I suppose then I could have discussions on Fedi as well, which is kind of slick.

Projects

With US politics being what they are, I find myself a little stressed out. I'm hoping that I can actually devote a little attention to making some progress on things. I do, in tiny, granular amounts now and then. But some of these I've been thinking of for years. Here is a selection:

• Power inverter/battery charger
• Solar MPPT charge controller
• DC-DC converter for microgrid type application, sharing power between DC buses
• Solar Pi, a Raspberry Pi web server powered by a solar panel, such that it's running only when the sun is shining

Really, the inverter is the thing I'd most like to get going. I more or less know how it should work, but as I envision it it will require learning a new microcontroller architecture, and designing a few boards. It will be a bit of an odyssey, but should actually be useful.

The Solar Pi is sort of a concept art project I came up with, and I may put that just beneath the inverter in terms of priority.

Animals

I may be adding a dog to my household. It will certainly be the source of plenty of pictures, as well as of preemption to the above projects, if it works out. Stay tuned.

Distractions

I just try to stay busy. It's easy to get caught in a doom loop. I hope everyone reading this has various ways they can escape the grind now and then. Take care of yourselves.