Project SolarBot - aka "Rob"

One of the projects that I was finally able to start this year was SolarBot. Technically he is the first "sun chaser". Well, let's start from the beginning. Since the dawn of time, or at least the creation of solar panels, we have had a problem. How do we maximize our harvests? So far the answer is either we don't, or we use a "sun tracker". Obviously, we want to harvest as much as possible, but "sun trackers" only work up to a point. In the realm of "guerrilla solar" they are huge, clunky, barely "better than nothing" solutions. So I started building "SolarBot" aka "Rob". He wound up being dubbed "Rob" because I started using him to prototype different concepts, not just chasing the sun.

His purpose is to follow the sun or at least move himself to maintain the most sun exposure, to recharge batteries, or perhaps act as a mobile power circuit. When I get a chance I will show you the path he will ultimately have to traverse. For now, his range will be only about 30 feet. Why does he have to move at all? While I don't know about the rest of you, I happen to live in this place called the real world. As such, and as you can tell by the photo, we have trees. Trees cast shade. Cutting down the tree is not feasible, as I live in the desert, and I rely heavily on my big tree to make life bearable in the summer. This also makes a problem for solar. It means that as the shade moves, so must my panels.

Anyway back to "Rob". I misspoke in one of my early posts about how many lead acid batteries I have. I said I had 1, but I actually have 2. "Rob's" main system battery is a 10amph SLA. This is a must, because I still haven't figured out the hot box for the battery. Lithium batteries can't handle the winters here without being heated, because the wind chill can bring the temperatures down to -65 Fahrenheit or colder. His body was the big experiment here. I wanted to see if I could find an "off the shelf" solution. I always had this idea of using an RC car. That's how I started my first robot on fire many years ago. Yes, Rob's body is a giant RC Car! I created a rig to hold the platform for his solar panel, that's the big black board. The board is actually covered in rubber, not paint. The original idea was that he would be able to change the pitch of the panel, but it's not really necessary, because I live very near the 40th parallel. My panels can be flat on the ground and still be very close to "ideal" (I need to make an edit here; The panels do still perform better at an angle, but like always it depends on season and location.).  I use what I call a "Surveyors Panel" to check my angles. Maybe I'll show you how to make one some day. Anyway as soon as I get it, I'm going to use an arduino as the brain to make him move. At least at first. An arduino doesn't have a reliable "real time clock" so that won't work in the long term. I do have to get a new motor controller for him. I burned his RC controller out, getting him from the shop to the house. It was just a cheap chinese pos. It's really just a 15 amp relay board, not a proper motor controller. I image that we looked pretty stupid, carrying this 60lb car, with a black board on it, home.

Yes, there is still a lot of work to do on him. I'll try to keep some kind of an update going. Who knows, maybe one day he will do what he's supposed to do.

Solar kits - a good beginning or a bad investment?

OK,  so you went out to Harbor Freight, or some other popular store and got yourself a solar kit. You hooked it all up like the instructions told you to. You're ready to start harvesting enough power to free your family from the power companies, or at least keep a battery charged, right? Sadly, no. Why? You have the inverter hooked up, the sun is shining, the charge controller says you're harvesting, so what could possibly be wrong? So much, where do I start? I don't want to overwhelm you with technical crap, so where can I start that you won't be overwhelmed, and yet still get something useful out of my blathering.

I think I should start out by saying that I have a hostile beef with the people who designed these systems and those who sell them. Both are perpetrating a massive fraud and charge out the nose to teach you a very expensive lesson. I used a couple of these systems, years ago now, and I resent the cost behind the lessons. Mostly, I think, because they are taking advantage of ignorance, laziness (maybe I don't mind that one so much), and people who don't think they can afford to build a good system. I actually do still have one of these panels left. I use it to keep Rob charged, while he's idle. The idea is that these systems are supposed to deliver 4 amps of power, and that you will be able to use the inverter or direct power to run appliances, gadgets, or whatever in the event of a power outage. They even blatantly tell you that these systems can be used at the cabin or to free you from the power company, or keep your backup systems going. It's all a lie. There is a lot to understand, and I don't know if I can actually explain it all in one article.

Let's start with the panels. These panels are called "amorphic". They are touted as the "ideal" panel because the silicon is deposited directly on the glass via silk screen. From a manufacturing point of view that's convenient. The problems start there. From a power per square inch point of view, they are lousy. The makers claim they will produce better in low light situations. Nope. They are supposed  to have a diode built in to keep the power going the right way. Some do, but those that I found were not of the right size. Then there is the wire, undersized. Then the connectors, a toy car / trailer connector, work with them for any amount of time and you will go nuts, fry equipment, and probably leave solar forever. The panels are rated under "perfect sun", which is not even close to reality. I never saw these panels reach more than .75 amps. I saw that one time on one panel (1 out of 6) over a years time. These panels averaged only .25 - .4 amps, under "ideal" conditions. Surely, over a years time I should have had "ideal" conditions at least once.

What about the battery? It is usually a SLA (sealed lead-acid) which is OK, but it is usually only 10 to 20 amp hours. What's wrong with that? Nothing in and of itself. I use one to recharge devices and run my speakers. It's my last lead-acid battery, but that's another discussion. I don't think I should bog down with this right now because it's a very complicated topic. What can you do with the battery? Not much. It just depends on what you are doing. In technical BS you should be able to run a 20amp load for 1 hour or a 1 amp load for 20 hours. In reality that is not what happens. What about the recharge? They claim that you are getting 4 amps of power and that your battery will recharge in only a couple of hours. That is so flawed. The battery will only recharge at a rate of about 1/2 an amp per hour (the maximum rate is set by the internal makeup of the battery and other things). If you use the battery with a 1/2 amp load, you would be able to use the battery at a rate of 1 hour for every recharge hour (conditions matter). What is a half amp load? A solar water pump, some speakers, not much else. It's complicated and best left at that, I think.

What about the inverter that comes with the kit? Where do I stop laughing? It's usually a 150 to 200 watt inverter. Sounds really impressive doesn't it? First, you need to understand that the inverter converts DC power (direct current) from the battery or panels into AC (alternating current). The second thing you need to understand is that, because of this that and every other thing, it takes about 5 AC amps to do the work of 1 DC amp. That means your battery will drain very quickly. What can you do with this inverter? Run a light bulb for about an hour, maybe. You might be able to run a laptop for about 15 minutes. It all depends. I was able to run a 150 watt bulb for about 2 hours, or watch TV for about half an hour, being very careful so I wouldn't hurt my battery.

What about the charge controller. That's the last important part. You will notice that most of the controllers let you put the power into the battery, but not get it back out safely (for you or the battery) or conveniently. Not totally junk, perhaps, but darn near. I still have, and use, a couple of these sometimes. If you know how, they can still be useful. The problem is, is that these systems are supposed to be easy for beginners to set up and use. Most beginners don't have the knowledge or experience to get the power out of the battery safely.

What about the cost? I paid $400 each for two 3 panel kits. Was it worth it? NO! I have been building and developing my own panels since then and I don't think I have yet to spend $800. The solar door for example (details upcoming eventually), has a potential of 9 amps, and the panel parts cost about $150, maybe. So I really got burned cost wise. Experience wise, I have to be a little more generous. It got me off my butt to build a better system and figure out real costs. Of course, since I've been working in solar / alternative energy, for so long, I would have had to get a kit just to check it out anyway. So I guess, there was some good with the bad, and I came out ahead.

Solar with a Purpose (and a few other odds and ends)

Solar power production, usage, and storage, is a nightmare to explain. Mostly because of misconceptions, misinterpretations, and flawed ideologies, on the part of people who listen to sales people, teachers, professors, and just idiots who have never touched a real panel, much less ever built a system. People who go on endlessly about "perfect conditions", "perfect sun", "perfect angles", on and on and on. Then to you have those who go on about "the devices will only consume this much", "the ideal temperatures",  "this humidity", until the air is so filled with BS that it leaves me running for a shovel. Of course, then you have the "I'm always right about everything" crowd. Who are experts on every condition and environment known to man. Where's my shovel.

One of the tenants of Guerrilla Solar, is to use "dead spaces" to generate power. This idea should be useful, with varying results, for everyone. Dead spaces aren't being used for much anyway, so anything produced is good. For example; I have a building downtown that I am "solarizing" that has a door that we call our "power door" (a project for another post). I basically turned it into a potential 9 amp solar panel. To date we haven't harvested more than about 4.16 amps at a time, but that is because the system has only needed that much at a time. Is this an ideal setup? No. Does it produce enough power to run the planet or even a small moon? No. Does it produce a usable amount of power to accomplish even a tiny task? Yes. You will probably hear me say that "Ideal" and "Perfect" don't exist, so get used to it.

I think that, what you the readers, need to keep in mind, is that your results will most likely not be the same as mine. Some of you will use crappy equipment. Some will have questionable building skills. Others will have IQ's that are lower than the cells you are using. Some of what I hope to show you will not be applicable to others. Some of the things I do are made necessary because of where I live (where I am almost happy to say is surrounded only by about 1 million other people in a 300 mile radius in any direction and 5 million cows). I have also been working with solar and alternative energies "in the trenches" for 20+ years, and have learned some nasty little secrets the hard way. There are a lot of shysters, liars, cheats, and crooks in this area of endeavor, and they all see you as a fast buck, a fast vote for some internet contest, or just an idiot. 

New Project - BevyBot

It's not really a "new" project per se. I've been wanting to do some of my projects for years, but I have only recently started some of them. Anyway, this new project is "BevyBot". It's main purpose is to keep my bevies cold. I also want it to move around to charge itself, and come to me when called. I don't get visitors, but if I ever do, it would be cool if BevyBot was able to offer them a nice cold drink. Especially since I'm the worlds worst host. I don't get any practice at it so I don't get any better.

So far I only have the prototype for the cold box and already it's a bust. It's moot at the moment because where the box is, the temperature rarely goes above 40 degrees Fahrenheit. That's a good temperature for my bevies, but obviously it needs to be that on the inside when the room is 115 degrees. The reason it's a bust is that the peltier unit is only drawing the air temperature inside the box down 5 degrees. The setup is simple so far as you can see by the picture. It's just an arduino to control the fans, a cooler for the body, a thermometer with a probe outside and inside the box, a battery for the arduino, a cpu cooler, and a heat-sink inside. The peltier is powered by one of my solar panels. The panels can deliver about 18 volts at 3.5 amps, but spends its time more like 18 volts at 2 amps. That's not really to my liking, but I didn't get all of my panels built this summer, so I'm short on power at the moment.

When the arduino is on it powers the relay which turns the fans (one inside and one on the cpu chiller outside) on and off. They aren't needed at the moment, because it's so cold in the room. I do run them sometimes to try to make a difference in the temperature, but so far no good. It is interesting to me that the heat-sink inside gets quite cold, but that it doesn't translate to the air temperature. Like I said it drops the air temperature only 5 degrees.

So what's next? I need to get more power somehow. I need to figure out why the peltier isn't doing what people claim it's supposed to. That's one of the problems with people online, they copy each other endlessly and it's hard to know if they are being honest or not. Even if they have done their own work or not. I'd like to try to get a frame built so that it can move and then put a battery on it. I'm thinking that it will need to have two batteries; one for mobility and life support and another just to run the box.  I'll just have to see what I can manage next. It's early in the game and there is a lot of work to do on it.

Welcome to Guerrilla Solar

This being my first post, I thought it would be a good place to welcome everyone who has an interest in the fine art of power harvesting. Of course, "Guerrilla Solar" is not just about solar panels and batteries. It's about using the power we harvest. It's also a bit of solar usage, that is, using the energy from the sun to do work without solar panels too. At least that's what I hope will come from all of this. Anyway, thanks for stopping by.