Frequently Asked Questions
Wind Turbine Power
Q. How much power will a wind machine produce?
A. Machines are rated at maximum output at wind speeds of 30-35 MPH. A 10 KW machine will produce 10 KW of power per hour at that wind speed. Since that type of wind is not always blowing, the multi-blade design enables the start up generation of power at 3-6 MPH and as the wind speed increases, so does the power output.
Q. What if the wind isn’t blowing?
A. If you have a utility interconnect there is no problem as the utility’s power takes over. If you have been connected to the power line and putting your excess power into the line causing your meter to turn backwards, you will have a credit until the end of the year that you can use when you have to buy electricity from the power company so you will not be charged unless you use more power than you have a credit for. With an independent remote power system, power that is stored in batteries can be used during times when no power is being generated
Q. How tall of a tower will I need?
A. A tower must be no shorter than 15 ft above any obstruction within 300 ft radius. The minimum recommended height is 30 ft. A good way to find out how tall your tower will need to be is to use 5 helium balloons with a 100 ft string. Every 10 ft put a ribbon down to the height of 30 ft, and watch which ribbon is sticking out straight, that is the height you want to put your machine for the best performance. Make the ribbons about 10 ft long.
Q. What is the power factor in the Wind?
A. Every time the wind doubles, the power factor increases 8 times (8:1 ratio). For example, if you have a 10 KW wind machine and the wind would blow at 12 MPH for 24 hours you would get 49.9 KW in that time. But if the wind would blow 24 MPH but only for 12 Hours, you would get 419 KW in that time.
Q. What size machine will I need?
A. The size of machine needed depends upon the amount of power you use. The higher the electrical demand you have, the larger the machine needed. Also if you live in an area with low wind you would need a larger machine in order to produce the most power with the available wind.
Q. What kind of tower should I have?
A. You could have a guyed tilt tower, which is less expensive or you could have a free standing tower which costs more. A free standing tower does not need to have guy wires so it uses less overall ground space, and a free standing tower also has better stability.
Q. What is a Guy-Less Tilt tower?
A. A GLTT is a 40’ tower that hinges 15’ above the ground. It can be lowered by one person with an industrial hand winch with a built in disc brake.
Q. What does an inverter do?
A. An inverter converts DC power to AC power.
Q. What voltage can I use?
A. Inverters come in 12V—24V—48V, 120V DC to 120 Volt AC power.
Q. What is a Sine-wave Inverter?
A. A Sine-wave Synchronous is true 60 Hertz cycle just like household power from the power company.
Q. What is a modified Square Wave Inverter?
A. Modified Square Wave works with most appliances, but can not be interfaced with the power line.
Q. Can I run my house with wind power?
A. If you live in a windy area and have battery back up.
Q. Should I get a three blade, a single blade, or a multi-blade machine?
A. If you have a constant high wind, you could use a two or three blade machine. If your average wind is below 12 MPH you would be much better off with a multi-blade, as they start at much lower wind.
Q. Do I need a gearbox?
A. A gearbox has up to 50% friction loss.
Q. What size machine should I buy?
A. Big enough to take care of your power needs. It is recommended to go 25% above your average power consumption.
Q. Can I sell my excess power?
A. Yes you can sell your excess power. The Federal Government requires that the power company buys the power. Check with your state utility commission as states have different incentives for alternative energy.
Q. What is the most efficient type of turbine?
A. The permanent magnet machines are the best in direct drive generators because they are 90% efficient.
Q. What is a permanent magnet alternator?
A. Permanent magnet alternators are self energizing. It does not need to be fed with power.
Q. Should I combine wind & solar?
A. Solar and wind are a good combination. You will always get some amount of power from solar during the day, even if it is cloudy. On most cloudy days it is windy, and on most clear sunny days there is little wind so they compliment each other.
Q. What if I do not get enough power from wind & solar?
A. You could add more wind machines or solar panels, or you could add a generator for stand by power. Or you could cut back on your consumption to conserve energy.
Q. Should I buy more batteries?
A. Remember that you should never mix old and new batteries. No matter how much you start out with, if you keep drawing out of it, and don't replenish it you will run out!
Energy that Does Not Cost the Earth
Whether you are interested in reducing domestic electricity bills, Net metering or just Generating green electricity to power your business or home, Eco Builders can work with you to find your sustainable energy solution.
