When it comes to wind or solar power you have 2 questions to answer. First, how much are you trying to produce. You said, "help power my house?" In this case, any size you are comfortable purchasing and installing will help. If you want to run everything most of the time like we do, then you have some more math to do. The second question is, "Do I want a stand alone system that can operate without grid power, or just produce some power to dump into the grid." This is important. We had a stand alone system for years, meaning if we produced too much for our home and our batteries were full, then the rest was wasted. But it also means if the grid power goes down, we still have power. Grid tied systems need the grid to operate, they use it like a battery. They are less expensive and simpler to install, but cannot operate if the utility company has an outage, they simply shut down. There is a third type system just coming out, a hybrid. It has a battery bank, but ties to the grid at the same time. If the grid fails, it will power your home until the battery runs down. If you have wind or sun, this might be all week. These systems are the most expensive to purchase and operate, and more complicated than the other two, and are less efficient because they use some power keeping the batteries charged all the time.

For most people that want to get started, I recommend they build up a small system first and experiment with it. We did 11 years ago, it had one small panel, a 50 watt size, 4 golf cart batteries, and a 300 watt wind turbine from Southwest Windpower that was designed for a boat. Everything cost us $1,100 USD, and everything except the turbine is still operating today. We use the 12 volt power for kitchen lights, small electronics, like cell phone chargers and flashlights, and a radio and fan. There is a great magazine called Home Power that gets into doing all these things, and it doesn’t cost much to subscribe. They even ran 2 articles on our home, one on our small system, and another on our full sized one several years later. If you subscribe, you can use their online search to look for those articles, search for, "Small System First." There are also some great websites, I will list some below.

As far as building your own wind turbine, it can certainly be done, but look for instructions first. And shy away from the vertical axis types, they look really cool and people say they are better because they can take wind from any direction. Wind only blows one way at a time, and the horizontal units have no problem with this because of thier tail. The real reason is because the vertical units are horribly inefficient. Generally they convert about 5 to 8 % of the incoming wind to electricity, horizontals run closer to 30%, this is why all the power companies are using the horizontal types. Check out Mick Sagrillos article about them in the AWEA website to learn more. Do some more reading, and if you can, get to one of the energy fairs listed in the back of Home Power, we did 12 years ago, and that is how we got here today. Good luck Chris, and take care, Rudydoo

A Wind Turbine can be connected to the power grid for an unbelievably small amount of money. Even then, solar Power is subsidized, as well.

In most areas of the world, wind power depends on expectations, and is a slave to expectations.

God bless those that can take advantage of this.

Here, in NYC, at Ground level, we can count on 9 mph. Hardly enough to make sense. But at higher levels???

I Propose that every building, above 14 flooors, in NYC have a wind power plant. What a great GREEN thing to do….

and what is the electrical power output of the turbine lkikely to be ?

please show the working out.

thanks

Hey Avatar, rather than my giving you the answer, I’ll send you to the source and you can see the formulas and examples along with explanations yourself. It’s interesting to note that the most efficient turbines today only convert around 25 – 30 % of the winds energy to electricity, or torque. There is a theoretical limit of 39% called the Betz Limit, named after the engineer that discovered it. Vertical axis rotors, for all their popularity are very inefficient, around 5 – 8 %. They look really neat, but you don’t see any of them in the utility power companies wind farms, there is a reason. Check out the American Wind Energy Association website at AWEA.ORG, or google, "Wind Turbine Power Formula," and look for a link to the AWEA website, it is all spelled out there. Good luck, and take care, Rudydoo

Figure about $10k-$15k. You need to install a device that will keep the phase and frequency of your wind turbine in sync with the grid. The name of the devices escapes me at the moment. But Google grid connected power systems and you’ll get a relatively good idea. it also depends upon what equipment you are including. Is your turbine charging batteries? Then are you using an inverter to convert the battery DC to grid AC? That will add cost. There are a host of other things you must consider.

Now the reality:
Wind is NOT constant — and is not dependable. I think you need at least about a 7 mph wind, just to begin turning the propellers. If the wind can not remain at better than 7 mph, you get ZERO power. What then? So then in addition to the wind turbines, you need at least 150 MW of "other" generation — such as Natural Gas Turbines (basically a stand alone jet engine) , or a coal fired power plant. So now you have expensive costs for "redundant" generation.
In addition — this is their "maximum" generation at say a 15 mph wind. What happens when the wind is only 10 mph? You maybe get only 50 MW when you need 150 MW. Big Problem.
Then, the biggest problem: On a hot 95 degree summer day — when everyone needs power the most — everyone is running their Air Conditioning all out. But now that is the days the wind is NOT blowing. If the wind was blowing — it would be much cooler. So on the hottest days, when the most power is required — the wind does not blow — and the wind turbines produce no power.
Then the maintenance issues are so bad on these wind turbine units that many companies are just abandoning these wind units in place, and just walking away. They are not economical at all. Without massive "Government" subsidies — free money from the Government — our tax money — no one would even touch these.
The installed costs are high — the maintenance costs to keep them running are high — there are additional cost for the "back-up" generation that they were supposed to replace, but in reality can’t replace.
It may be a Politically Correct policy right now — but in reality not a good or rational decision.

Wind turbines are those large modern structures that you see with 2 or 3 blades that look like airplane propellers. The blades revolve and are coupled to generators to generate electric power.

Windmills are rarely built today, most of the ones you see are old. They have 4 large rectangular blades. The blades are usually coupled to an internal mechanism, like a flour grinding mill.

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higher inertia comes from,
a.blade angle
b.projected area of the blades
c.mass of the blades