The Answer is Blowin’ in the Wind

BWS Publisher George Day takes a look at how wind power can solve your onboard energy problems.

On the last leg of a 1500-mile hopscotch delivery of our Jeanneau 45.2 Lime’n with our partner Tony Knowles and his son Jeff aboard, we came in from the sea through Fort Peirce Inlet on Florida’s east coast and turned north to find a ball in the secluded mooring field at Vero Beach. It was New Year’s Eve, a Saturday and a lovely afternoon, so the Intracoastal Waterway was abuzz with small boats, fishing craft and speedboats festooned with girls in bright bikinis.

We motored into the harbor to pick up a mooring and found 77 other sailboats already swinging on rented town moorings. This is one of those special spots where experienced cruisers gather in early winter before dispersing to South Florida or the Bahamas. You could tell how self-sufficient many of the boats were by the rigs and gear onboard. Of particular interest were alternate energy installations—just four months earlier, we had installed an AirBreeze wind generator on a pole on our boat’s stern quarter. We chose the new 160-watt model, which replaced the AirX 400 watt model.

In a dinghy survey of the Vero Beach cruising fleet, we were pleased to see that of the 77 boats present—almost all of which were larger than 40 feet—64% were equipped with at least one wind generator. The AirBreeze and older AirX systems were the clear favorites, with 68% of the boats so equipped. Other systems included two Rutland six-bladers, four five-bladed Ampairs (both small diameter systems), four Kiss systems, three Ferris in-rigging 200s, and three unidentifiable three-blade systems.

We did not have a decibel meter with us as we dinghied about the moored fleet, but in the 10 to 12 knots of breeze, there were some noticeable differences in the sound levels coming from various models. The Air models had varying degrees of fairly high-pitched whispering sounds similar to a mild wind blowing through a pine tree. The six-blade units were basically quiet, with no noticeable tip noise. The larger two-blade and three-blade units had deep swooshing sounds. One unit that I could not identify had a definite whomp from the blade tips. Yet even with this chorus of wind generators, the overall sound in the harbor was primarily that of wind in the rigging.

There are three basic types of wind generators. The small six- or five-blade types tend to start generating power at lower wind speeds than the larger models. They are clearly quieter and fit more neatly on smaller boats. The output from the smaller units varies, but on average over a week or a month, both the Ampair and the Rutland will serve up between 20 and 40 amp-hours in a 24-hour period. That’s just enough to keep the fridge cold.

The three-blade systems are larger in diameter, requite a more robust mounting system and will be incrementally noisier. But they will also offer a greater output, particularly in higher wind ranges. The Kiss has shown that it will generate, in steady winds, between 60 and 100 amp hours daily, which is a good amount for a cruising boat. The AirBreeze, which we have, will do better in steady winds than in average conditions and will provide between 80 and 120 amp hours on average.

The two-blade wind generators are larger and require an even larger mounting system. Because of this, some skippers opt to hoist their generators on a staysail halyard in the foretriangle where the blades can turn high overhead and will be unobstructed by the bimini and dodger aft. The Ferris 200 is the monster generator, as its size suggests, and can put out as much as 200 amp hours in a day in strong, steady breezes. For those who will be anchored for long periods while exposed to the trade winds, the 200 will allow you to sell electricity to your neighbors.

But, steady winds are often the problem since along both coasts of the U.S. and in the lee of the islands in the tropics, the wind is often less than trade wind strength and not as efficient at turning the blades of your wind generator. There is a tradeoff to be made between high-end capability and low-end efficiency. When we were looking around at the choices, we wanted to make sure we installed a unit that would be efficient in the lower wind ranges. Plus, we wanted a unit that fit the boat aesthetically and was a product of the latest thinking on the subject.

The new AirBreeze, which we settled on, is one such wind generator. The company has built and installed more than 135,000 small wind generators worldwide and has been through several generations of design review and product improvement. This is not to say that other units on the market would not do the job well for us, but we did have to make a decision.

There are a couple of aspects of the new AirBreeze that we like. The unit is quieter than the AirX. It has a magnetic breaking system that kicks in when the circuit is switched off; the blades turn very slowly, which generates just enough juice to keep the brake on. The unit is rated to wind strengths up to 110 miles per hour, but we doubt much would survive aboard in that much wind. The new unit will start putting out a trickle charge at 7 knots of breeze and really gets going when the wind hits 12 knots.

It took about four hours to mount the AirBreeze on its pole and another two hours to wire in the connections to the batteries. We installed a vacuum switch that controls both the small solar panel and the wind generator. This allows us to prevent any surge from the engine’s alternator from damaging the AirBreeze’s internal circuits.

In real life, the AirBreeze is a great source of power for the batteries, but not the complete solution since we are so often moored or anchored in well-protected harbors or marinas. The unit really comes into its own when cruising and hanging on the hook or when sailing on a reach or upwind.

On the last leg to Florida from Georgia, we had headwinds about a third of the time and then stronger quartering breezes. In both conditions, the AirBreeze churned away, generating enough amps to run the boat and all of its electronics, lights and lifestyle systems—even the laptop computers.

Generating enough energy is always a problem on modern cruising boats. A wind generator like the AirBreeze we installed is truly the answer.

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