Charging a Battery Bank Using an Alternator

I have been using an alternator to charge my batteries for years. In my residence everything is powered by the inverter. Normally the batteries are charged by my solar array, if I want to use a power intensive device like my wood thicknesser or if the weather remains cloudy for several days I start up a Kubota diesel engine turning a 24 volt 55 amp alternator Bingo, in goes the charger and up goes the voltage.

The solar trade call this "direct charging" and it is an efficient way to charge batteries using mechanical (engine powered) means.

Direct Charging is also what you will do if you own a motor home or caravan or use a battery for energy in a recreational vehicle or 4WD. Basically it goes like this in a vehicle: While traveling you use your vehicle alternator or auxiliary alternator to charge you battery bank. When stationary the solar panels take over.

Commercially available direct charging plants are certainly available however it is comparatively easy to make your own. Full information on doing just that is available in our book "Build Your Own Direct Charging Plant". Another advantage of a home built unit is that you can actually use an alternator as a welding plant. My Honda powered 110 amp 12 volt charger doubles as an efficient, electronically adjustable welding plant and is as good as any basic mains type welder I have ever used. This plant is pictured left. All the required information to construct a direct charging plant similar to these is contained in our book "Build Your Own Direct Charging Plant" (ISBN: 0-9581100-2-6, $25.00 Aussie dollars).

Sorry, this book is sold out. New edition available December 2009