 Electricity produced by wind generators can be stored in batteries for use as, and when, it is needed.
Yacht owners often deploy a combination of wind generator and solar panels, thus getting the benefit of most types of weather.
The power that can be obtained from the wind is variable as a cube of the prevailing wind speed. Double the wind speed is eight times the power!
So a 5 knot wind creates only an eighth of the power generated by a 10 knot wind! 5 x 5 x 5 = 125 but 10 x 10 x 10 = 1000! For example, a 10 mile per hour wind has one eighth the power of a 20 mile per hour wind. (10 x 10 x 10 = 1000 versus 20 x 20 x 20 = 8000)
Not long after we arrived in Chaguaramas, Trinidad, in the West Indies, in the Spring of 1998 we met Douglas Billings, inventor of the KISS Wind Generator. He had his premises at Tropical Marine, one of the smaller marinas around the bay.
The KISS generator was an impressive machine so we weren't altogether astonished to hear that it was rated the No.1 wind generator afloat by the Seven Seas Cruising Association in their Equipment Survey 2000.
The KISS Wind Generator was designed to supply the energy needs of the average cruising sailboat from the wind energy available in a tropical Caribean anchorage.
Doug Billings had set out to create a wind generator that would operate quietly but still produce plenty of power. He wanted his machine to be capable of operating in a gale yet stoppable at the flick of a switch, eliminating the need to approach the wind generator while it is in operation.
He was determined to use only materials that were resistant to corrosion and to ensure that the owner could service a KISS generator with parts that were easy to find in any part of the world. He achieved all of those objectives.
The rotor is highly cambered, with twist, taper and elliptical tips, providing maximum torque at a relatively low number of revolutions per minutes (RPM) and producing only minimal blade noise.
The three blades are produced by creating five layers of bi-axial glass roving, pressure-moulded in polyester, providing great strength with minimal flex and very little weight. The blades are bolted to an aluminum disk, in turn screwed onto the threaded motor shaft.
Incorporating nickel-plated neodymium magnets and commonly found (and therefore easily replaced), plastic sealed, #6203 metric ball bearings, the motor is a brushless alternator, designed to match the low speed characteristics of the rotor blades.
Maintenance should, as a result, be infrequently required, simple to do and, just as importantly, inexpensive.
The motor fits directly into a two-piece fiberglass housing, bolted together through the motor, using four stainless steel bolts sealed with silicone. Additional weather proofingis provided by the oil seal on the motor shaft.
Incorporated in the housing is a graphite-impregregnated bearing surface. This 'mates' to a machined PVC plug. The plug can be introduced into any 1-1/2 inch (schedule 40) pipe. A threaded PVC unit screws into the base of the housing to lock the unit onto the mounting pole. A loose spring eliminates the need for a troublesome slip ring and allows the unit to rotate.
The KISS wind generator weighs a total of 23.5 pounds. The aluminium disk and the blades weigh only 4 pounds, exerting only minimal pressure on the 3/4" motor shaft and bearings.
The rotor has a radius of 30 inches. The housing is 24 inches in length and the controlbox is 4" by 6" - a compact unit by anybody's standards.
 The testing of Doug's wind generator was carried out by mounting one on a truck and driving around at varying speeds, recording the output.
An ingenious way of checking the machine out without having to wait for the right conditions to prevail!
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