Over the past few years, the media has focused attention on new small wind inventions and “technology breakthroughs,” creating havoc and confusion among consumers, The hype of selling a new turbine design is often initiated in a press release that’s poorly vetted by the unsuspecting or uneducated reporter. Most of these designs are marketed as being roof-mounted, and many, though not all, are vertical axis technologies.
We frequently get questions about such designs, although it is very difficult to educate a reporter or homeowner on the physics and fluid dynamics of airflow and the engineering of such designs in a few paragraphs or a short phone call. However, examining the history of small turbines can be very useful.
Vertical axis technology actually predated “modern” horizontal wind-electric turbine designs. In the 80-plus years since their invention, vertical axis turbines and most all other manner of unique rotor designs have given way to two- or three-bladed horizontal axis turbines atop tall towers. Why? Because they work, they generate electricity, and most importantly, they do so economically over many years.
The latest eye-candy gizmo that inevitably generates little energy because it sports a small collector (that is, rotor) and is sited on a rooftop or short tower where there is little to no usable fuel is soon abandoned in the marketplace. This is Darwinian economics at its best. To quote Dutch wind expert Eize de Vries, successful modern wind turbine designs have come from “evolution, not revolution.”
If you insist on pursuing unusual designs that are touted as new or superior technologies, but provide little to back up their claims, make sure that you look beyond the marketing hype. Then, seek out satisfied owners—those without a vested interest in the sale—and ask them about their experiences with the turbines. Don’t take it from us, but listen to the many people who have been burned and, unfortunately, soured on small wind technology because they made a poor investment choice.