admin answers:

Hey Marcus, there are two reasons, cost and efficiency. The old grain mills had to transmit the torque to the building at the bottom mechanically, they didn’t have electric generators and voltage regulators in those days, if they did, they would certainly have run a pair of wires down that tower instead of some gears and push rods. The other reason, efficiency, is a bigger player today than it was 100 years ago. Most modern turbines today, which generally have 3 long slender blades instead of a dozen or so square metal ones can convert about one third of the energy in the moving column of air to electricity. The old style turbines you saw on farms centuries ago were maybe 5% efficient. The other reason for those big rectangular blades was starting torque, mainly to start the water pump. They were not interested in having the thing run well, or at all in 100 mph winds with tremendous RPM’s, it would simply destroy the entire mechnism.

We run our home on solar and wind right now. Our wind turbine is a commercially made unit a little bigger than a ceiling fan, but can develope almost 1000 watts in good wind. It is small and light enough to take up to the top of the tower in a backpack and install by hand with ordinary hand tools, that was the main reason we selected it. For our home, we should have a larger one, maybe 1500 watts or so, but the weight of the generator almost requires the use of a small crane at that point. I do not know of anyone using helicopters to install or service rotors today. The large commercial ones actually have ladders built into the inside of the tower, and space to work inside the tower top housing. Smaller ones like mine either go on a Rohns Guyed Lattice tower, or similar type of tower, which has a ladder built into the framing for climbing, or they use a crane truck to reach the top.

In our experience the last 11 years, the only thing that needs periodic service is the electronics, regulators, and batteries, which in our case is at the bottom of the tower. In fact, those devices are all in our battery room in the garage. Our previous turbine was a smaller unit with the generator and electronics all in the housing. Each time the regulator burned up or malfunctioned, the entire unit had to come off the top of the tower. This was the main reason we upgraded to the unit we have now. Exposure to the elements, gusty winds and even lightning never seem to bother the generator itself, so we make very few trips up the tower these days. Take care Marcus, Rudydoo

admin answers:

Here is a great website if your looking to make your own wind turbine at home.

Www.Squidoo.com/HomeMade-Green-energy

admin answers:

Oh you northerners 🙂
I’m from NC, so listen up. Unless you are on the coast, you won’t need to worry. Just be prepared if your area is forcasted to be in a flooding zone. By the time it gets up there the winds are supposed to be mostly tropical storm force, so don’t worry about that unless you have large trees on your property. You should have a few things though:
-enough bottled water supply for a few days
-first aid kit
-flash lights
-batteries, lots and lots of batteries
-weather radio in the event the power gets knocked out
-possibly a generator if you really want power in your home
-non-refrigerated food
-and also have supplies in the event that you need to clean up your property afterwards (chainsaws, brooms, leaf blowers, etc)

I’m supposed to get hit tonight/tomorrow so I’ll be having fun. Good luck!

admin answers:

You’re asking a difficult question only because the technology is improving each month. What is the best today probably won’t be the best next year. For wind power you will need a wind availibility survey describing the average wind conditions throughout the year for your locality. Every homesite is a bit different. To establish a cost/benefit analysis your first have to know how much wind energy is available.

admin answers:

The question is written to allow for a rather simple solution, unlike the challenges of real wind turbine power and energy estimation.

Energy = Power x Time

Electric power produced = conversion efficiency x gross wind power

Gross wind power = power density x turbine swept area

So, with all the equations at hand, we can solve the problem.

Turbine swept area = 2 x pi x (25 m)^2 = 3927 m^2
Wind power density = 500 W/m^2

Thus, Gross wind power = 500 W/m^2 x 3927 m^2 = 1.9635 x10^6 W = 1.9635 MW

Electric power produced = 0.25 * 1.9635 MW = 0.49087 MW

Since the problem identifies the wind power as long-term average, we can calculate the average energy produced in a year.

Energy (Joules) = Watts x seconds
Energy = 0.49087 MW x 31536000 s = 15.487 x10^6 MJ
But the question asked for energy measured in kilowatt-hours (kWh).

So, Energy = 490.87 kW * 8760 h = 4300100 kWh produced in 1 year.

Unfortunately, a real wind turbine would produce this energy in an unscheduleable manner, typically peaking when the demand (load) is lowest. That’s the challenge of wind energy.

admin answers:

Wind energy is not continues and hence it is not going to cut your bill drastically. Even the wind farms can built not to feed continuously to the grid but intermittently. For individuals the cost of wind turbine is going to be very expensive compared to the power bill. Good to go for one with the impact on environment but if you ar going for saving dollars then you are going to be disappointed.