Domestic wind turbines have taken a lot of stick over the last few years, mainly because they do not produce anything like the output the manufacturers’ claims. Although this is true in some cases, the main problem is siting the turbines in unsuitable locations with inadequate wind supply.
Small home/residential wind turbines at first got a lot of bad press for not performing the way that buyers expected. Usually, however, the main problem was due to improper siting, or location, of the turbine. Before purchasing or installing a wind turbine, it is important to check the wind conditions in your desired location. (Links are provided below for finding average wind speeds in the US and UK.) Once the location has been confirmed to be suitable, the manufacturer of the proposed wind turbine should be requested to carry out an in-depth wind survey. (Click the image to enlarge.)
Typical Wind/Power Output Charts
The Skystream Residential Wind Turbine
One of the latest innovations in small-scale wind power turbines is the Skystream residential wind turbine. It produces 2.4kW output in optimum wind conditions, which is possible due to its design and tall mast.
This is an article on residential wind turbines, and in particular the Skystream 3.7 mode. We begin with an examination of the main components and installation details.
Skystream Wind Turbine Diagram
Image: Drawing by Willie Scott, 21/10/2010
Skystream 3.7 Model Key Components Description and Installation
The Skystream residential wind turbine has the following components:
- Nacelle - The nacelle contains all the operating components, and is air cooled through vents at the top. It also has a transmitter aerial fitted to transmit real-time information on the turbine's performance.
- Blades -Three 6’ fiberglass composite blades are shaped to optimize performance in the available wind. These are designed to operate quietly, safely, and efficiently, which is achieved by managing the blade-tip speed using a built in electronic control that also almost eliminates the noise associated with small wind turbines.
- Rotor - The rotor houses the blades and drives the alternator through a shaft which passes through the nacelle. The wind cut-in speed is 8 MPH and rated power is at 29 mph, with the rotor operating between 50 and 330 RPM. An electronic stall-control regulating power control and RPM offers protection against over-speeding and high winds.
- Alternator - The alternator is a unique neodymium permanent magnet, slot-less design, being a direct drive from the turbine rotor by a shaft passing through the nacelle.
- Inverter -Converts the power generated by the alternator to suit the household power.
- Sound Isolator - Fitted between the nacelle mounting and the supporting tower it consists of anti-vibration mounts and sound insulators, preventing transmission to the tower.
- Tower - The tower, onto which the nacelle is mounted before installation, is around 35’ high. it has a flange at the bottom for fitting to foundation base.
Concrete founds are poured into the excavated area into and long corrosion-treated foundation studs are set into them.
Once the foundation is dry, the tower is erected and lowered onto the studs, lining up the flange holes with the foundation bolts. Once aligned and its verticality checked, the bolts are tensioned. A trench is dug for the power supply from the turbine and the cable is laid from the base of the tower, to the house distribution board via a disconnect switch.
1. youtube - installation video.
2. bithenergy - description of Skystream wind turbine.
Summary of Skystream Features
The Skystream has the following features:
- Blades – These are swept blades and designed to be quiet, efficient, and safe. Their main advantage is in their shape and their tip speed being electronically controlled.
- Real-time Monitoring - This is enabled by software supplied by Skystream, which when downloaded transmits the turbine operating and output values and conditions wirelessly, through an on board transmitter.
- Alternator – This is a unique neodymium permanent magnet, non-slotted design which is directly driven by the turbine rotor.
- Rectifier – Converts the current and voltage to household suit supply from grid.
- Noise Reduction – Noise reduction is achieved by the electronic control of blade tip speed. The direct drive requires no gearbox, and anti-vibration bolts between the nacelle mounting and the tower provide additional quieting.
Tower – The 35’ tower enables the turbine to use optimum air currents. This is the same height used for wind socks at aerodromes.
1. skystreamcommercial - Manufacturer’s description and specifications.
2. windpoweringamerica - map of USA giving information of wind conditions by area.
3. segen – map of UK giving information of wind conditions by area.