The March Hare: Winter '98
Issue 15

Get rid of the grid

by Cecil Scheib

In the last issue of the March Hare, Tony described the unfortunate demise of our conventional power-sucking refrigerator and celebrated the arrival of its brand new SunFrost superefficient replacement. I'm sure it's been hard for most folks to sleep nights, wondering how things were going for the Rabbits and their new fridge. Well, I just wanted to let everyone know that our new fridge is friendly as a new puppy with a chew toy, and give a reminder that starting to break free of the grid monopoly is something almost anyone can do. Read on to see what we've done and get some tips about how you might do the same.

To begin with, we've recently added three more essential components to our system. First, we purchased more power, in the form of a 75-watt AstroPower solar panel. With our three panels (now totalling 175 watts of power), and our Air 303 wind generator also hooked into this system with eye-catching red and white wires winding across our ceiling, we've finally got power to burn. Hopefully someone will soon donate an electric hot tub so we can take advantage of our surplus production capacity.

Second, we added new batteries (4 Exide GC-4s we picked up in St. Louis to avoid shipping charges on these heavy items). Now we have the capacity to go for almost a week without sun or wind, and still have that chilled tofu smoothie. It was a relief to stop worrying about draining the batteries.

A Trace C-40 Charge controller

On the other hand, our expanded production capability meant we had to think about not overcharging the sytem and destroying our fancy new battery bank. We managed the system by hand for a few weeks, turning the solar panels out of the sun when battery voltage (determined by a cheap voltage meter I soldered together as a "learn while you do" project) got too high. While this would work if we were always at home and very attentive, it began to tire us out. Enter high technology: a Trace C-40 charge controller. The C-40 not only regulates battery voltage, carefully charging them in a way that extends their life, but also keeps track of how much power has been added to the system. So, we've begun to create a "power log" that records the amount of electricity we generate from our off grid system.

Finally, stress-free cold food, without nonrenewable power sources...whew! Stop by for a cool lemonade proudly displayed sometime.