Wind Power

Small wind turbines, towers and hybrid controllers for off grid sites.

Wind is worth doing if your site is genuinely exposed and consistently windy. If it is not, the same money spent on more panels and more battery will give you more power on average, and we will tell you so. Where wind does earn its place is alongside solar rather than instead of it: it generates during winter and at night and through the cloudy, windy weather when panels produce least, which is exactly when a solar only system is most likely to come up short.

The reason the site matters more than the turbine is that power from wind goes up with the cube of the wind speed, so a site averaging 6 m/s and one averaging 4 m/s are nearly a factor of three apart. That is also why tower height matters as wind speed increases with vertical height, and why a turbine tucked in behind a shelterbelt or a house is wasted money no matter how good the turbine is.

The turbines run from 450W at 12V up to 3500W at 48V. The 400W is a 1.7 m three blade rotor for about 70 kWh a month in a 5.5 m/s wind. The 1KW horizontal is the same on a 2.4 m rotor for about 175 kWh a month, in 24V or 48V, and both cut in at 3 m/s and sit on a 6 metre tower. The vertical is a five blade aluminium rotor at 24V, supplied with its hybrid controller and dump load. The 3500W at the top is a 3 m five blade rotor at 48V, about 450 kWh a month in a 5 m/s wind, and it also comes with its controller and dump load.

Every turbine needs a wind controller, not a solar one. A turbine cannot simply be disconnected when the battery is full, because with no load on it there is nothing holding the blades back, so the controller sends the surplus to a dump load instead. The hybrid controllers here take a turbine and solar (optional) at the same time and come with the required dump load. The TriStar controller does the same job by diversion and handles hydro as well.

Every output figure on these pages is quoted at a stated wind speed, and it is worth reading it that way rather than as a monthly total. Tell us your site, how exposed it actually is and what you are generating already, and we will tell you honestly whether wind is worth doing.