A Floating Wind System Richard Perez For every stationary home power producer there are many who roll down the road or float on the water. Many RVers have written in requesting articles about home power systems that move. Well, here's a mobile wind system that not only makes its own electricity, but also its own motive power. The Agua Alegre The Agua Alegre is a 35 foot long wooden sailboat. This Alden designed sloop was built in the mid-1950s and usually is docked in Santa Cruz, California. This yacht, like most boats, is a self-contained energy unit. All electrical energy used on board is produced on board. During long cruises on sailboats, electrical power generation can be a very real problem. The wind provides the motive power for the boat and the auxiliary engine isn't operated for many days at a time. The Agua Alegre shares many problems and solutions with land based systems. Every Watt-hour removed from her batteries must be replaced. Electrical energy in land based homes is important. We rely on this energy for comfort and entertainment. The situation aboard a boat is much more serious. Much of the electricity used on the Agua Alegre is for critical services essential to the safety of the boat and her crew. The Agua Alegre's Electrical Consumption Most of the energy used on board is for essential navigation and communication devices. Aboard the Agua Alegre battery stored energy supplies the radar, LORAN, depth sounder, marine VHF radio and several Ham radios. Running, deck and cabin lights are powered from the battery's stored energy. The anti-electrolysis system protecting the boat's hull from corrosion and the bilge pumps are also electrical consumers. All electrical consumption aboard is 12 VDC. The Agua Alegre consumes no 120 vac power and is not equipped with an inverter or ac generator. This is in keeping with the simplicity of the boat, which is not equipped with such things as microwaves, refrigeration, or other electrical luxuries. According to the Agua Alegre's skipper, "If you want to survive and have fun at sea, keep it simple." The Agua Alegre's Power Sources The primary power source for the Agua Alegre is the wind generator pictured below. INSERT PICTURE OF WIND GEN This simple unit was hand made for the Agua Alegre's skipper, Mary Duffield, by her friend, Ted Baer (2120 N. Pacific Ave #61, Santa Cruz, CA 95060 or call 408-426-1304). The wind generator uses simple components like a bicycle wheel assembly and a permanent magnet DC generator to directly recharge the batteries. During the time I spent on board the wind generator was continually operating. Eventhough the generator only supplies a few amperes to the batteries, it is almost constantly operating. It supplies more than enough energy to light and maintain the boat when docked. In fact, while docked Mary doesn't even bother to plug into shore power. While sailing the wind generator produces enough energy for intermittent radar operation and constant operation of communication equipment. The second power source aboard the Agua Alegre is her diesel auxiliary engine. When operating, this engine spins a 50 ampere alternator. In the days before the Agua Alegre was equipped with wind power, the diesel had to be run every few days while the boat was at sea. In order to shorten the periods of engine operation just to recharge batteries, Mary installed a Mk. VI Field Controller (see Home Power #2, page 23) as a replacement for the standard voltage regulator. This field controller enables faster and more efficient refilling of the batteries because it is both amperage and voltage adjustable by the user. During the four years that the Mk. VI has lived in the Agua Alegre's engine compartment it has done its job without any problems. INSERT ENGINE COMPARTMENT PHOTO Mary is considering adding a PV or two panel to the Agua Alegre's electrical system. There are times when the wind completely stops and the boat is becalmed. In this case, a PV panel could supply the electricity essential to navigation and communication without running the diesel auxiliary. During our visit to the Agua Alegre, I checked out many sailboats on the Santa Cruz Yacht Harbor. I was surprised not to see a single PV panel anywhere. In this, the "salties" could learn a thing or two from their landlocked RV cousins. Energy StorageÐ The Batteries The Agua Alegre is equipped with two completely separate battery banks. This approach always assures one full battery pack to start the engine, and is common in most mobile systems. A special switch allows the engine to charge or be started from either or both battery packs. Each battery pack is composed of marine, leadÐacid, batteries and has a capacity of 220 ampere-hours at 12 VDC. These batteries are securely mounted in waterproof cases, low and in the stern of the boat. Placement of batteries in any moving vehicle, especially sailboats, is critical. Since the batteries are very heavy, they should be located as low as possible and as close to the vehicle's center of gravity as possible. The System The Agua Alegre is a wonderous and harmonious system. Brian Green and I spent the night aboard, safely tucked in her wooden belly. A small storm was brewing and the wind machine on the fantail was working overtime. The 2 meter ham radio squaked softly in the background. As I went to sleep, thoughts of the power of the wind went through my mind. What a wonderful planet we live on. Nature is very kind to the Agua Alegre, she moves her through the water and supplies the energy to keep her batteries full. I had very pleasant dreams.