Tiny Solar Power for a Rainy Day

Tropical Storms in the Gulf, tornadoes in Alabama and lots of rain.

That’s not a time when you’d normally think solar power, except how little the panels are putting out. It IS a good time to hole up with a small project.

In the last post, I mentioned the Tiny Watts group and their tiny projects. And I mentioned that Solar George had given me an idea. I had a couple of small solar panels from garden lights. I found them in the dumpster at a house I was rebuilding, so free solar is always good. I think I may have another from a light I bought that didn’t last long. Anyway, these two put out about 6 volts in good sun. A load will drag them down to 5v, so that sounds good. I would guess they are in the 2 watt neighborhood, so that sounds tiny. Next, I scratched up a couple of micro-USB cords and cut off the big ends, leaving a few inches with which to work. I buy those by the sackful, because they get lost or messed up. No telling how many are stuck in the seats of my truck.

Strip back the wires on the big end of the USB cord and plug into a USB charging source to determine what wire does what. USB has 2 data wires and a shield in addition to the power wires. I guess right that red and black were the positive and negative, but don’t assume yours is the same as mine. Check the polarity. Toss the big end and strip back the insulation of the small end a bit. Leave enough room to get some shrink tube or tape on the joints when the soldering is done.

Cut off the connector on the panel and figure which wire does what. In my example, blue was negative and brown was positive. Your mileage may vary. Red to brown, black and blue is the order of the day.

Warm up the soldering iron and find the solder, shrink tube and/or tape. I slipped on small shrink tube over each conductor of one end and then a bigger, longer piece to cover the entire joint. I didn’t have any heat sealing marine shrink tube or I’d have used it to seal out water and make a better physical grip. Wrap and solder the joints, slip over the shrink tube and heat shrink it with the solder iron, a torch or a heat gun.

I plugged it into my Motorola flip phone, the only kind that works where I live, and it told me I was using an unauthorized charger. It is fussy that way. No problem on my LG. I plugged it into my Tomo 18650 battery bank and it went to charging, even with the heavy overcast. I can use the 18650 cells, recycled from the many laptops I have outlived, in my flashlight or charge two phones at once and I can charge them at night. My Motorola gets along with it. Since the battery bank has two USB ports, you can even plug your iPhone cord in. The microUSB with the solar panel is more useful, I think, because it plugs into more things and you may be able to still end up charging the iPhone.

Yes, I know you can buy a battery bank kit with built in solar charger and even an LED light for just a few bucks on eBay, and I may even get one, but this project was recycling some good junk box stuff and making something useful. The long wire on this version will let me stick the panel outside and keep the stuff getting charged inside out of the rain. Order one of the kits and build your own if you don’t have stuff in your junk box. Good fun on a rainy day.

Warning: Different phones react differently, so keep an eye on it. This is unregulated, so don’t wander off, leaving the phone plugged in to overcharge or damage the phone. A 12v panel wired to one of those cheap USB cigarette lighter adapters may be safer.


In the News

Just a few notes on solar in the news. Click in the parentheses for the links, since I can’t seem to make them show up in some browsers.

A really biased (headline) blames California power outages on climate change. The actual cause of PG&E outages is PG&E pulling the plug when it gets breezy! Proper powerline maintenance, line stabilizers and right-of-way maintenance to reduce fuel would go a long way to prevent fires from powerline sources. Better forest management wouldn’t hurt, either. Of course, they famously turned off the power to millions and there were fires, anyway. Today it was reported that they turned the power back on and a line fell from one of their newer towers (47 years old), starting another fire. The positive thing coming out is people and businesses are scrambling to find solar and battery solutions to keep their power on and their businesses open. They could learn a lot from John’s customers in Haiti.

Next up is recycling. Solar power has changed so fast that facilities are changing out the panels they installed a few years ago, going for the higher output of today’s panels in the footprint of the old ones. That leaves truckloads of perfectly good panels looking for a new home. That’s just one way John brings cheap panels to Sun Electronics customers. That’s why you can buy a 70 watt panel, single piece, for $12, or as low as $7 in quantity. Or a 300-ish watt panel for a hundred. Another source is insurance claims. It seems that if a half dozen panels get popped in a hailstorm, they’ll go ahead and replace the other hundred thousand, just so they’ll all match. More bargains. You and I putting those surplus panels to work is the best form of recycling. Then there are those that are well and truly smashed. As John has pointed out in his blog, there’s no good way of recycling them, yet. The growing pile is prompting lots of new research on ( recycling and reclaiming. ) Of course, there are new surplus modules, too. Companies go bankrupt or get into some sort of bind and there’s another container load of them.

Finally, something fun. Are you wanting to try your hand at solar power? Is your kid looking for a science fair project. Check out the American Solar Energy Society’s ( Tiny Watts) program. Program members build their tiny watt phone chargers, battery chargers, portable lights and all sorts of things. I guess the solar toys John used to have would qualify. I put a solar powered spider on the table in Mom’s sun porch and it would drive her cat nuts! Inspired by Solar George, down in the Keys, I found a couple of 6″ panels from a yard light and will turn them into USB chargers. I figure you can use them directly to charge a phone, but I will go one better and let it charge one of those USB battery boxes. The battery box, using 18650 cells reclaimed from my pile of old laptops, can then charge two phones any time of the day or night. What kind of Tiny Watt project can you make? Check the link, above, for ideas.


Show Time!

John was just about worn out when I talked to him, yesterday.  He’s at the big solar show in Salt Lake City.  Sun Electronics does not have a booth, there.  He’s there to hobnob and network, catching up with old friends and keeping up with the latest offerings.

All of the panel makers are there, including the Chinese, who are not selling a lot of modules owing to the tariffs.  I’m sure each maker is emphasizing that their panels are blacker, less reflective and .001% more efficient than the panels in the next booth!  Not to say that all panels are created equal…they aren’t.  That’s a good thing because there are special applications.  In the next day or so I will write about some renegade panels I have come across and how to use them.

So, there he is, shuffling down the aisles, gawking, trading business cards and peeking in on seminars.  They have modules, inverters, batteries and every conceivable gadget and gizmo related to solar and what do you think catches his eye?  A racking system.

John recently had the opportunity to buy a small solar farm.  Not just the panels, everything.  Right down to the last nut and bolt.  Even the galvanized iron posts ripped from the ground with balls of concrete around the base.  I   would love to get ahold of stuff like that, but there is a problem.  Shipping.  It costs more to ship it than it is worth.

That’s really a shame.   Rather than reuse a perfectly good item, it is cheaper for them to sell it as scrap and have it melted down to make something else.  In the meantime, I can go to the local steel supplier, cut and drill the raw materials and  get busy mounting panels on the new rack.  How can that possibly make economic sense?  How much energy is involved in all that?

Yup, shipping is a real problem for us little guys.  Roberto just sold me a pallet of panels at a super low price.  I didn’t need them, just can’t pass up such a bargain.  Then there was the reality of a $500 shipping tab.

Well, this racking product that so impressed John is completely modular, meaning it is adjustable so it fits with any module AND it fits in a package you can ship UPS.  Hooray!  We’ll see if he can work out a deal to carry that line.

Another racking product I saw in show literature is a rackless system you can use on a commercial building with standing seam metal roofing.  These little assemblies slip on the seam, you space them just so, snug them up and drop on the solar panel.  Saves materials and labor costs.  Great ideas.

New product news from my morning solar newsletters and not the Utah show has to be the worst idea ever.  In addition to the current thin film offering that last a long time and the crystalline modules that seem to last forever, there are many other ways of getting power from the sun at much greater efficiencies.  The problem with most of these is that they do not last very long.  Some last only a few weeks.

The idea is that if they can get a super efficient panel to run 10-15 years, it may be economically feasible to build these disposable panels and just swap them out every 10 years!  Now, I understand that land is expensive and if you can get more power out of an acre you can save some money.  What about the cost of labor?  What do you do with the scrap panels?  It takes a lot of energy to make a panel and a lot to melt it down and start over.  Why not just make forever panels and leave them alone?

I don’t think this idea is being promoted for rooftop, but imagine having to replace your home PV system every 10 years?  I know when I get my new roof, I am going to get the best I can find and I really don’t want anybody stomping around up there wearing it down.

Besides, what does that do to the secondary market?  You won’t be able to have such a broad choice of used panels at low prices that you have today, at least ones that actually make electricity.  My thought on PV recycling is USE IT!  Run it until it fades to nothing.

Speaking of recycling, someone has come up with a strange new idea to make it easier to recycle modules.  You grind up a tree and make a cellulosic substrate on which to apply the active material and all the silver wires.  Sounds like paper, to me, but cellulosic substrate sounds more impressive.  Anyway, a hailstone cracks the glass or some other problem arises and it is time to recycle.  Simply soak the panel in warm water and the cellulosic substrate dissolves and all of the valuable or tricky materials slide off into your waiting hands, leaving the glass and aluminum frames available for conventional recycling or even reuse.

Wait just a minute.  MY modules are out in the weather every day, not that it ever rains in September.  Do I really want a panel that dissolves when it gets wet???  I’m thinking there is a detail or two they didn’t mention in the press release.  At least they are trying.

As far as my recycling efforts go, I just ordered a pallet of those FS-270 panels John is offering so cheap.  70 watt used thin film panels for $7!  I’m bound to find something to do with them.  Heck, I bet they’d make great stocking-stuffers come Christmas, birthday presents or even something for a kid’s science fair project.  Ummm, maybe not, as they have an open circuit output of 83 volts.  It is never a good idea to electrocute the nieces and nephews.  Anyway, they look like good, cheap fun.  Check them out on the sunelec.com home page.