Discharge Rate (hours)

Given the site-specific requirements for our battery, we decided on a GNB 6-75A15 Absolyte sealed battery (630 amp-hours at a 20 hour rate). Although considerably more expensive than an equivalent lead acid battery, the Absolyte battery offers several advantages for the frozen North. It is highly tolerant of freezing temperatures, does not gas during normal charging, requires no watering or equalization charging, has a lower self-discharge rate than lead acid batteries, and exhibits better performance characteristics in low temperatures. On the down side, you can't check specific gravity and if you gas the battery by overcharging it, you can't add water.

The Absolyte battery is often used in remote non-maintained sites. Sunelco and Soltek both recommend this battery for installations such as ours. GNB claims up to 1,200 cycles at an 80% depth of discharge for this battery. However, to be on the safe side, we try not to discharge our battery more than 40 to 45% (59 amp-hours daily usage times 5 days without sun divided by the 630 amp-hour battery capacity equals 47%). Our battery is seven years old now, and seems to be performing as it was when it was new. Without the ability to do specific gravity tests with a hydrometer, the Amp-Hour + meter is critical for checking the performance of our battery. I plan to do a direct capacity test on the battery next summer to see precisely how it is holding out. The Cruising Equipment manual has a great section on doing capacity tests. In case you haven't seen it, and because so many people ask me how to do a battery capacity test, I include a brief overview on page 58.

Who the Heck is Rube Goldberg, Anyway?

The best general information I got from Ron LaPlace at Photron was to over-design the system to allow for future expansion and to "Do it right!" When presented with the initial cost of a total alternate energy system, many opt to cut corners and to undersize and "jury rig" the system. This is false economy and will cost you dearly when you find you want to expand your system in later years. I know I was initially inclined to cut corners and undersize our system when I was adding up the cost of my solar experiment. Take my advice— Don't!

Cutting corners is not only dangerous, but it often results in a real "Rube Goldberg" contraption which will fail, or at the very least, drive you crazy. I have seen too

Above: Bill and Lynda, in front of their remote lakefront retreat.

many systems with automotive voltage regulators, multiple connections to the battery bank making it look like an octopus, and panel interconnects made with solid core 14 gauge interior wire. I even saw a set of lead acid batteries installed right under a propane fired Paloma water heater one time. Holy Imminent Explosion, Batman! Trust me, don't do any of the above, or at least buy insurance policies for your loved ones if you insist.

Even low voltage DC electricity can be fatal if mishandled. If you don't believe me, go out and dead short the positive and negative terminals on your car battery with a crescent wrench. Congratulations, you have just discovered Ohms law and learned how to weld at the same time. Here's what happened: your wrench created a connection between the battery terminals with almost zero resistance (infinite conductance). Zero resistance results in almost infinite instantaneous amps. Infinite is a big number. Look out at space if you don't believe me. This is why your wrench is welded to your battery terminals. Your battery is probably wrecked. Don't blame me. Phone George Ohm's relatives—it's his law.

Other Energy Use

We pump water with a 1/2 hp 117 volt submersible Jacuzzi pump. Water is stored inside the house in two fiberglass holding tanks and fed into a 12 volt pressure system. Our storage tanks hold 180 gallons, and we need to refill them every three weeks. We use the power plant to run the pump, and at the same time, we use the charger on the Trace inverter to boost the battery bank.

Electrical System Costs

(1990 Canadian Dollars)

Electrical System Costs

(1990 Canadian Dollars)





DIY Battery Repair

DIY Battery Repair

You can now recondition your old batteries at home and bring them back to 100 percent of their working condition. This guide will enable you to revive All NiCd batteries regardless of brand and battery volt. It will give you the required information on how to re-energize and revive your NiCd batteries through the RVD process, charging method and charging guidelines.

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