Letter: Solar Fence Chargers as Alternate Power Supplies

To HJL and JWR:
I’m a dry land crop farmer, cattle rancher, and hog producer in Montana. Through my work I find things that make me think I could use WTSHTF. (Yes, I’ve read your books). One thing I wanted to offer up, if you haven’t tried it, is a solar powered electric fence charger. These charges cost from $170 to $500. But to charge a few small items the PV panels on the smaller $170 to $300 models are plenty large enough. The chargers work by solar powering a gel cell battery. The [battery] terminals can be changed with a couple tweaks to charge or power about anything. It’s a very inexpensive and simple way to have some power when needed and on a plus side a new gel cell battery has a shelf life of around 10 years, making it a very easy item to store for the future at your retreat. Thank you, – Troy

JWR Replies:  Keep in mind that most solar electric fence chargers provide pulsed power, using both an intermittent relay and a transformer. So for almost all of these charger designs, to get any useful power for various small electronics you will have to tap into the gel cell battery terminals directly–not attach your power cable to the unit’s fence-charging external terminals!