We’ve posted a new article over at Old School Tech about solar panel principles. As always, we keep the technical details over there, and handle the self-sufficiency and controversial issues over here. Go check that article out, and come back for more details.
The linked article mentions the steadily declining price of solar panels on a per-watt basis. In the past year, our dealer prices have dropped about 20%; consumer prices have dropped about the same. This trend has been going on for a while. As a result, solar panels are not a great choice for trade goods, ammo would probably better. Unlike ammo, which once delivered to someone with a suitable firearm, can be universally used, in the case of solar panels, the “firearm” is an entire system of racking, cabling, chargers, inverters, batteries, and so on. No one is going to make use of significant power from these without all that infrastructure. In other words, the available market is very limited. Buy them because you can use them, unless you are willing to trade the entire system or have enough of the supporting giblets on hand to trade with them also. There are many better choices for trade goods than solar panels.
One exception: small panels in the 10 watt to 50 watt range are almost universally useful for small battery charging tasks. Even those little car cigarette lighter nuggets that create USB charging outputs can work straight off of some panels in many cases (be sure to check that your nugget can use 12 volts to 24 volts). Cell phones and other computing devices aside, there are a growing number of useful devices that can benefit from USB charging, especially LED lights. Even so, the prices for this range of solar panels will also continue to steadily decline, but at least the small panels themselves will have more or less stand-alone intrinsic value. If you are taking the trade-goods approach, you should also stock some of those little cigarette lighter nuggets. On Amazon these are about eight dollars each, but some companies give them away as promotional items. These cost about a buck and a half to get printed with the logo, if you offer them a couple of bucks each for several they would probably be happy about it. Be sure to check the voltage range printed on it first.
Even without a charger, you can put a solar panel to work as a fixed voltage source by putting what is known as a “buck converter” on it. Amazon is littered with inexpensive options for these, you can buy them fully assembled cheaper than we can buy the parts to make them. We’ll show how to use them in a future Old School Tech article. In a pinch you could use one as a battery charger if you were willing to watch it.