What can I do with this wind turbine?
We received a question today that was a wake up call. We forget not everyone lives and breathes wind energy.
Ok, so what can you do with this wind turbine? Once you complete the steps in the instructions that come in the box, you can run an inverter from 12 volts or 24 volts and power common plug in appliances, laptops, lights, fans etc... If the wind is blowing you will be charging the battery with 2-160 watts. Add a solar panel and you can up that amount considerably. Watts accumulate in the battery so you can only take out as much as you put in. If you want more power storage you can add another battery in parallel.
100-300 watt inverters have dropped way down in price and can be purchased at your favorite store for a few$$$.
LYNX Wind runs shop lights, coil winders, laptops all off wind and solar. Adjusting your power usage is probably the quickest way to reducing your power bill. Adding wind and solar are far more expensive than just turning off lights and appliances. Wind and solar are more a matter of choice and desire than practicality in our western culture.
How Much power is in the wind?
Quite a lot of power. If there is enough to fly a kite there is enough to use. The problem is making something big enough to catch enough to be meaningful. The bigger the turbine the more stress on parts and the more people notice the machine. There is a balance between strength, efficiency, aesthetics that all have to be taken into account when putting up a wind turbine.
So for a 1 sq meter Turbine like the LYNX Seagull we can calculate the amount of power available in a 14 mph wind (6.25ms).
Of that power available we can estimate yield based on the type of design. Multiply available power by 40% for a really good turbine.
The result is 59 watts. Now consider that an alternator and wiring runs might be 60% efficient at best. The resulting power converted from wind to electricity will be about 32 watts. Now if winds are 28 mph the power in the wind goes up by a factor of 8x, however efficiency of the blades may decrease as the blades are bypassed and the also the alternator becomes less efficient as more power flows through the copper wire.
Calculating power based on average winds over a year will give you a sense of how much power there is.
How Much power will a wind turbine make?
This question is probably the most common and one of the biggest areas for misunderstanding in the field of wind power. For years many wind turbine companies were tempted to quote theoretical peak power in hopes of luring buyers their way. It's a tempting trap. More and more reputable manufacturers are now adopting a more honest approach and quoting average power in typical winds. But even that can be a bit of a sales pitch if the peak power is quoted. The truth is wind isn't steady from one moment to the next. It can vary by 100 watts in a second.
All that said, there has to be some way to compare a turbine's capability and efficiency. Looking at real wind data logged over a long period will reveal an average power curve. When you look at this data plotted it will look like a wide range of power for each given wind speed. This is because the moment before, winds may have been increasing or decreasing and some of the inertia is being stored or dissipated. The best way to look at the power output is to draw a trace through the scatter plot and expect that much power at any given wind speed.
The only constant is that wind is free.
What is TSR - Tip Speed ratio?
Some wind turbines turn no faster than wind speed. On a large diameter this can appear to be quite slow. On a propeller type turbine the tips may be traveling at 6x the actual speed of the wind. This can cause some annoying noise similar to the way a cracking whip can make quite a sound. A lift type VAWT will turn at 1-3 times the actual speed of the wind and under the speed at which produces sound.
A higher TSR is desirable to extract energy from a rotary alternator producing electricity. It means the resistance can be less, which results in more power, and less wasted as heat.
This is the tendency for a typical alternator to have a stiff feeling when you start turning it. You will feel a thump thump feel as the magnets attract to each of the steel stator poles. Given enough force this is quickly overcome and is not a big issue. But for turbines that have a low starting torque in low winds it is a big issue. That is why it is important to avoid cogging type alternators for small wind turbines. A non-cogging alternator has no steel in its stator and can free spin with the slightest of breezes. Cogging type alternators also lose some power to eddy currents - magnetic currents swirling through the steel laminates. This will turn to heat and requires air cooling. A non-cogging alternator only loses power due to the resistance of the windings.
Not everything that goes around in the wind makes power. CP is the abbreviation for coefficient of power. There are two important components in determining power from a blade moving through wind - lift and drag. If a blade produces just slightly more power (lift) than it takes to move through the wind (drag) it may have enough to use for making electricity, grinding grain or pumping water. A drag turbine doesn't use lift. It basically turns because the turbine blades or scoops exhibit more drag going with the wind than upwind. It will never turn faster than the wind and may have little power to use. A lift type turbine can exhibit tremendous power minus very little drag if it is designed well. This excess can be used for doing work. The trick is how to design for the desired rotary motion while lessening to a great extent the drag in the same rotary motion.
Can I power my house with wind?
An average house may use 2 kw on average, with peaks of 6 kw or more. To make this much power would require a windy location and a swept area as large as a small garage. Then the power needs to be stored for peak use, so that in times of calm the power can be drawn off. It really isn't practical. Personal Wind Power should be seen as an adjunct to regular grid power, and solar. On windy days you can put a significant amount of power into your home grid offsetting your power bill.
Can I power appliances directly?
In experiments at LYNX Wind CFLs and LED bulbs have been lit nicely by wind, however the bulbs can be quite dim one moment and way over powered the next. There is a danger that if the power to the load becomes too great, the load such as a bulb may burn out leaving no loading on the turbine. This is a dangerous situation for a wind turbine because there is nothing to slow it down.
The blades are very light and not as sharp or high speed as a typical propeller type turbine, however the turbine should be mounted above the reach of anyone. The voltage from the Sea Gull with its high output alternator should be respected. When it is connected to a 48 V battery or lower voltage battery, the line voltage is completely safe. However, if the output was left unconnected to a battery it could reach several hundred volts with high amperage - enough to be fatal. Never operate a wind turbine unconnected to a load!