admin answers:

It is not mechanically feasible to make a DFIG with a sufficient number of poles to match the synchronous speed to the optimum speed of a wind turbine. The space required for numerous stator windings would make the machine too large and heavy for mounting in the nacelle of the turbine. Since the speed increasing gear can not be eliminated entirely, the DFIG speed and the gear ratio are selected to optimize the cost, size and weight of the combination.

A PMSG using rare-earth magnets can be designed for a speed that allows the gear to be eliminated. The resulting machine has a larger diameter than a DFIG of the same power rating, but the cost and weight of the PMSG without a gear make it competitive with the DFIG package. The complete package comparison includes the cost and complexity comparisons of the electronic power conversion units and the expected reliability comparison of the two packages.

This is the basic outline of the design considerations. The complete analysis must be rather complex and contain assessments that are not viewed in the same way by everyone who undertakes such designs.

admin answers:

The only cost effective installation I’ve seen is at a home where connection to commercial AC power was very expensive. The home owner was quoted about $15000 to run a line to the house, and this became the alternate energy budget. Several solar panels, both for electricity and water heating were installed on the roof. A wind generator was installed on a 80 foot pole to supplement the solar panels. Battery banks, inverters, etc were installed inside to power the house. All appliances were selected to be very energy efficient, lighting was minimized, but remained adequate. The total price was less than quoted for commercial power, and comes with the added benefit of no further electric bills other than routine maintenance and repair of the system.

I think that if there is commercial electricity available you will be hard pressed to justify the expense financially. I’m installing a wind system to supplement the electric use in the house. Payback looks like it could take 10-12 years, but I’m not doing it as a money saving project, but rather as something to experiment with and learn. Instead of wasting money on cigarettes and beer every week, I’ve stashed money aside to finance my project.

I have pictures, electric diagrams, structural drawings, etc on my web page.
Http://members.rennlist.org/warren/wind.html

admin answers:

Here is an article that might answer your question from Ben Ford… He has been around for a while and is an experienced inventor and author on green energy .He showed me how cheap it is to build wind and solar… That will be me out there repairing my fence this summer and building solar and wind power!
Author Ben Ford
How would you react if your neighbor told you she was going to build wind turbines? Pretty impressed? The truth is that it is not difficult to build wind turbines and many homeowners are taking the challenge to build their own wind turbines as a cost-effective means to utilizing renewable energies. It isn’t exactly snap-your-fingers easy to build wind turbines either, but with the proper plans and a motivated builder you can be building wind turbines in no time.

It is definitely your best bet, before setting out to build wind turbines, to purchase an instruction manual or guide to follow. Remember that you get what you pay for when it comes to instructions. Make sure you find a manual that is easy to read with detailed instructions. There are also many online resources and forums to help guide you through your wind turbine building process.

To familiarize yourself with the basics, before you get started on your project to build wind turbines, there are four basic components to wind turbines. To build wind turbines you must be familiar with the towers, the batteries, the turbines and the tail and propeller assembly. The tools generally required to build wind turbines are simple as well, you will need wrenches, a saw and a drill. There may also be a need for additional tools depending on how of the wind turbine you will be building yourself.

One part that you will probably be ordering when you decide to build wind turbines is the motor. The motors on wind turbines do require regular maintenance and oiling for continued efficiency, but this is a small price to pay for the excellent energy these systems provide. In addition to the motor, you are definitely going to need a good-sized workspace. Depending on your target energy output, your propellers or blades could get up to 8 feet in diameter (4 ft blades).

It takes a little work to build wind turbines, but there is really nothing overly complicated about the process and generally the process can be fairly inexpensive once you are operational and your electric bills are dropping each month. Building wind turbines is also a fast growing occupation worldwide as technicians are tough to find. So learn how to build wind turbines for yourself and take advantage of the opportunities free electricity and know how can provide.

admin answers:

Hi Lara. We have been powering our home for 11 years now with the wind and sun. There are also solar water preheaters, rainwater collection tanks and a wood stove in the living room and shop. For the past 6 years or so, I’ve been going to the local schools and teaching seminars on solar power, and in some cases, the schools have run bus loads of kids out to our place to see a home like this first hand. One thing I’ve learned over the years is almost everyone asks questions about wind turbines first. There is something about them, the way they move, the noise people imagine when they see even a picture of one that draws their attention.

Wind power is actually a bit of work. The machines are mounted in very inaccessible places, they have moving parts that break down, they can make unwanted noise, and anyone within a quarter mile has to see the thing, yet everyone wants to learn more. Pictures of solar panels are cool, but they never move or even change color when they run. Pictures of a biomass operation sound absolutely ugly. Probably the wood stove would be the best of them. If it were me, and you wanted to draw attention with your poster, go with wind. Look online for interesting pictures of turbines, particularly in unusual places, like a remote artic weather station, next to a camping tent, on a sailboat or a mountain. A really good eye catcher is a big one with a technician hanging on the side of the tower in a harness working on the turbine. That really gives you a great idea how large the units can be. I’ll list some places you can look for photos, and information you can add to the poster. Good luck Lara, and take care, Rudydoo

admin answers:

I think with any system if energy is removed then the ‘natural’ state of the system must be disrupted somehow. With wind we must consider how much we are taking out of the overall system. The first thing to note is that the winds are largely driven by solar heating – causing high and low pressures to form through air density differences which act to even out by transporting air between them. The sheer scale of the energy and the vertical distribution of the wind means that even with our best efforts we can currently only harvest a small amount of the wind energy at surface level, let alone for the whole 10km of the troposphere. The effect that this will have is for the wind farm to be ‘seen’ by the lower winds as an area of increased surface friction, in a similar way to a large tree might be seen. This might lead to local effects close to the turbines but I don’t think it would be noticeable without high-tech equipment. As for global effects like El Nino then we would have to be seriously affecting the upper controlling winds (like the jet stream) and global circulation cells.
I would say that if the entire globe was covered in wind turbines then I would expect some dampening of the atmospheric circulation system, but since this is unlikely and we currently (key word!) extract a tiny percentage of the available energy then it is not of concern.

According to Greenpeace, we currently extract 6.0xE4 MW per year in the world. The total energy in the global wind is estimated at 3.6xE9 MW. With five orders of magnitude difference we have a long way to go before we impact on the wind in the atmosphere. Also there is a limit of 59% (called Betz limit) on how much we could extract.

To be green I think we should reduce our energy consumption, be efficient, and use the whole set of renewable available to “play with a full set of clubs”. In addition, I think we should return to this issue if wind power begins to extract a more significant amount of energy from the atmosphere.

admin answers:

Tidal power is a means of electricity generation achieved by capturing the energy contained in moving water mass due to tides. Two types of tidal energy can be extracted: kinetic energy of currents due the tides and potential energy from the difference in height (or head) between high and low tides.
The extraction of potential energy involves building a barrage. The barrage traps a water level inside a basin. Head is created when the water level outside of the basin changes relative to the water level inside. The head is used to drive turbines. In any design this leads to a decrease of tidal range inside the basin, implying a reduced transfer of water between the basin and the sea. This reduced transfer of water accounts for the energy produced by the scheme.

Tidal power is classified as a renewable energy source, because tides are caused by the orbital mechanics of the solar system and are considered inexhaustible within a human timeframe. The root source of the energy comes from the slow deceleration orbit of the moon around the Earth, and the deceleration of the Earth’s rotation. Tidal power has great potential for future power and electricity generation because of the total amount of energy contained in this rotation. Tidal power is reliably predictable (unlike wind energy and solar power).

The efficiency of tidal power generation largely depends on the amplitude of the tidal swell, which can be up to 10 m (33 ft) where the periodic tidal waves funnel into rivers and fjords. Amplitudes of up to 17 m (56 ft) occur for example in the Bay of Fundy, where tidal resonance amplifies the tidal waves.

As with wind power, selection of location is critical for a tidal power generator. The potential energy contained in a volume of water is

E = xMg
where x is the height of the tide, M is the mass of water and g is the acceleration due to gravity. Therefore, a tidal energy generator must be placed in a location with very high-amplitude tides. Suitable locations are found in the former USSR, USA, Canada, Australia, Korea, the UK and other countries (see below).
Several smaller tidal power plants have recently started generating electricity in Norway. They all exploit the strong periodic tidal currents in narrow fjords using sub-surface water turbines.____For more information go to the site below.

admin answers:

Homebuilt wind power generators can be built with just a few parts that you probably already have laying around your home.

If you want to power household items like TVs, washing machine etc then you will need an inverter. These are quite cheap though.

I got my instructions on homebuilt wind power generators from http://www.earth4energy.com and it made life HEAPS easier for me.

admin answers:

You are to be commended for pursuing alternative energy sources. Try one or all of the links bellow. I hope this helps.

Http://www.cetsolar.com/windpower.htm

Home

http://www.absak.com

http://www.solardyne.com

http://www.wind-works.org/books/wind_power2004_contents.html

admin answers:

About 6 MW is the largest. That size is many US$M.

Here is one list
http://en.wikipedia.org/wiki/List_of_wind_turbine_manufacturers

you can get others by searching for “wind turbine manufacturer”

admin answers:

Hey Chelsea. Wind turbines produce what is called wild AC initially, and not usable in most homes and buildings. Normally, the wild AC is converted to DC power, like a car battery by the wind tubines own control box so that it can be used to charge a battery bank of some sort. We have a home that is powered by the wind and sun, our wind turbine was built by Southwest Windpower of Flagstaff, AZ. There are other manufacturers around.

There are 2 primary ways to get the wind power into your home. One is a stand alone system like ours. The wind turbine and solar panels feed into a large battery bank whenever the wind or sun is available. Then a device called an inverter converts the battery power to normal household AC power and feeds it into the home. The other type which is fast becoming the desired approach is a grid tied system. You take the windpower and feed it directly into a grid tied inverter that converts it straight to the electrical grid, no battery. If you are producing more than you can use, the excess feeds out into the grid and is used by your neighbors, and your electrical meter spins backwards. If you are using more than you are producing, the shortage is made up from the grid and your meter spins forward. At the end of the month the meter is read, and you are billed for the difference. These are less expensive and simpler, no battery or charge controllers to buy or replace. The only problem is if the grid loses power, your wind turbine has to shut down, you can’t balance your turbiner directly to the needs of one home, the excess has to go someplace all the time. Hope this helps, take care, Rudydoo

admin answers:

Hey Jesse, you’re timing is perfect. Solar actually might be the best environmental way to produce electricity, but many of your anwers here are correct that it will never produce the power we need, not because solar isn’t powerful enough, but because the way we harness it is quite inefficient. Solar electric, or, “photovoltiac,” panels only convert about 12% of the incoming sun into electricity, the rest just heats up the panel. Arguments such as Erins that they offset agricultural production are baseless since most of these devices are on the roof tops of homes and businesses, or in the desert. Our home has been powered by the wind and sun for 11 years now, my panels sit on the garage roof, I don’t grow tomatoes up there, and they run the entire home. We have a wind turbine in the field behind our home, and in 11 years, I’ve never found a single dead bird under the turbine. The flower bed in front of our homes picture window is another story though. In the first days of the Altamont Pass wind project in California, there was a problem of dead birds, specifically Golden Eagles, which are rare raptors. Turns out the particular type of blade they used there mimmicked the mating call of these birds. Since then turbine blades have been redesigned, and the problem of bird kills has been pretty much eliminated. Solar electric panels are still very useful, but the real answer is actually in the desert.

The Germans are working on a project right now to use the sun and heat in the desert to make electricity which will be more like 60% efficient. How it works is they use large concentrators to focus the hot sun on collectors that heat oil to several hundred degrees. The oil is circulated into a huge insulated tank, then an oil to water heat exchanger is used to take sea water, boil it into steam and run a steam turbine. The turbine turns a generator and makes electricity. As a by product, the recondensed steam becomes fresh water, the salt is naturally extracted in the boiling process and seperated out, and the fresh water is then used to irrigate crops that will grow alongside the solar concentrators. So we can take a patch of desert, devoid of life, make electricity and grow food all at the same time with just the power of the sun. They will produce enough power to run all of Europe with just the northwest corner of the Sahara. No wildlife will be displaced, but the crops, partial shade and water will attract new wildlife to the area. Another benefit of this system is with all the oil heated and stored in an insulated tank, it can continue to boil water even when passing clouds shade the concentrators, or well into the night. So now we have access to solar power at night too. And the oil is continually recirculated, none of it gets burned or used up. Once it’s operating, it can continue to produce electricity and fresh water for decades without any emissions. It is very promising, and if it works as well there as they hope, I’m sure in another 10 years you’ll see them on all continents, including ours.

Stick with your choice for solar Jesse, we did 11 years ago, and our array puts out the same amount of power today as it did then. I’ve never turned a screw on my solar array or had to add a drop of oil, and our home has not been without power for even a minute in all those years. Hard to put a price on that. In your research you will undoubtedly hear the argument that, “Solar panels never produce as much power as was used to produce them.” This is blatently false, tons of research has been done to prove that the, “Embodied Energy,” in a solar panel is earned back in just a few years. But even if it weren’t, it wouldn’t matter. Coal, oil and natural gas electric plants never earn back their embodied energy because no matter how efficient they might be, once you build one, it then has to be fed more fuel to make electricity, so it never does get even environmentally. It always amazes me how we’ve been burning coal and oil for years, but as soon as someone comes up with something as clever as a photovoltiac panel, the world is always trying to discredit it. Keep that in mind when you are doing research and answering questions about this subject.

You can see articles and pictures of the project by clicking on the links below, or try venturing out on your own by googling phrases like, “Desertec Project,” or, “Northwest Sahara Solar Project.” You will probably find some great photos to use too. Take care Jesse, Rudydoo

admin answers:

The only vertical axis wind turbines I’m familiar with are the Maglev generators. You can find them at
www.greenstrides.com/2007/11/27

admin answers:

Here is a web site for you to start with

http://www.shop.solar-wind.co.uk/acatalog/marine_wind_generators_wind_turbines_aerogen.html

they supply small wind generators for boats, in both 12v and 24v application, capable of charging up to 3 banks of batteries. The web site will describe each system.

There is also much more info on line if you do a google search.

Http://www.google.com/search?hl=en&safe=off&rlz=1T4GGLL_enUS344US344&q=small+boat+marine+wind+turbines+in+europe&btnG=Search&aq=f&aqi=&aql=&oq=

hope this helps

admin answers:

The more exact distance is 2,140 miles, still it will take you at least 15 days if weather & winds work in your favor.

You will need at least a 36 footer minimum – 46 footer if you need to be a bit more comfortable.

Your problem will be not enough space for stuff, the kind of food you take, fuel, and fresh water. Not one sailboat I know of in the under 50′ range will carry enough fuel to run your motor continually for more than a few days. So, you won’t be able to carry enouth fuel to continually run your engine or generator – therefore, you will have to get food that does not require refrigeration.

The Pacific crossing in that area is not friendly.

Without all of you having experience on a sailboat on the open seas – you would be much better off buying 24 first class tickets on a cruise ship and taking more friends. It would be much more fun, and much less cheaper.

admin answers:

Forget about grants. If you want it bad enough you will get off your lazy butt and earn the money to build one. Why should someone else pay for you to have a wind turbine?

admin answers:

(I got this from my solar guy)
In New Jersey it’s a pretty good deal. I’m not making a political statement, just a financial one.

For Residential:
30% Federal Tax Credit
SRECs are good until 2026, currently selling at $655/SREC (which means for every 1MW produced). They are mandated by NJ State Law.

For Commercial:
30% Federal Grant
SRECs are good until 2026, currently selling at $655/SREC (which means for every 1MW produced). They are mandated by NJ State Law.
Accelerated Depreciation (allows you to depreciate 85%-100% of the cost of the system the first year)

The IRR is between 20-30%.
~~~~~~~~~~~
Good luck.