More than two years ago, I purchased and had my uncle install a replacement wind turbine, a propeller on its own mast at the back of the boat that the wind spins, turning an alternator. I bought a new one because the old one looked tired and parts were unavailable. Passive generation of electricity is important to us, helping us minimize the cost and time of having to burn hydrocarbons to charge our batteries.

As the wind spins the alternator, generated AC electricity is sent to a controller, called an MPPT (Maximum Power Point Tracking).  Among its roles, the controller monitors the output of the wind generator and compares it to the charge on the battery. If the battery is drawn down to a lower voltage than the wind generator is producing, the controller converts the AC volts to DC volts and sends the electrical charge to the hungry batteries. If the batteries are charged, the controller avoids the conversion, and the electricity goes nowhere. My problem is that our controller isn’t sending the product electricity the wind generator is manufacturing to the wanting batteries.

To confirm my suspicion, I followed Brett’s advice (a retired marine electrician and former commercial fisher, living in San Diego, a friend of my in-laws) and drew down Kandu’s house batteries from 12.9 volts to 12.0 volts, making them very hungry batteries. When the wind came up, the controller should have been eager to feed them, but it would not. Calling the manufacturer, a French-Canadian company in Quebec called Sunforce products, I spoke with one of its support technicians, Fernando (a not so French sounding name, I know). After laying out all that I had done to narrow down the problem, he independently came to the same conclusion: a bad controller. But it had been more than two years since I had purchased the unit and they had since discontinued the product. Arrgh! I explained to Fernando that I had been working hard these past two years to prep our boat for our circumnavigation. Although I had installed it two years ago, assuming that because it was new it would be fine, and although I was having my suspicions about the unit, it was only now that I had made time to fully test it.

Compassionate Fernando was not deterred. Sunforce had a few non-marine grade controllers left: one in the lab and a couple on the shelf. After testing them, without asking for a receipt or a serial number, just an address, Fernando shipped two units to me: the lab one because it was so well tested that he knew it would work, and a second, because neither were marine grade so he wanted us to have a back-up. The issue has delayed our departure by a week, . . . so what’s new?  When the replacement controllers arrive, it will take a day to install the lab one, and we’ll be right as rain, arguably better than had there been no problem. I’m impressed with Sunforce for backing its products the way they do. May the (sun)Force be with us!

Eric Rigney