Green Energy FAQs

If you have got any questions on Mini Wind or Green Energy in general, just ask. What are the big ??? that may be holding you back from setting up your own MWT or other Renewables generating equipment? This is a great chance for you to get meaningful answers. Simply type your questions in the input field “Leave a Reply” below.


  • Q: How much of a breeze does there need to be in order for the turbines to move? And, how tall should the thing be in order to get a good breeze?

A: Almost all current models start producing electricity at roughly 3 m/s (6.7 mph).

Turbines should generally have an unobstructed ‘view’ of the wind for ‘clean’ (as in energy-rich) wind to hit the blades. As a rule of thumb, you generally need to place a turbine twice as high as surrounding houses, trees etc. A 35 ft mast usually yields very good results for most homes.

  • Q: Why is roof-top installation of MWTs not recommended?

A: The problem with roof-top is that roofs generate turbulence which, in turn, reduces ‘what”s in it’: wind moves like a wheel and starts rotating around itself once it hits an obstruction, roofs, trees etc are definitely obstructions. “Clean” wind moves straight ahead and is, thus, more powerful when it hits an intended obstruction like a mini wind turbine that converts this clean flow a lot better. Such clean wind is generally found roughly at twice the roof or tree level.

This is why a free-standing mast of, say, 35 ft to 45 ft in most residential will give a lot better results.

  • Q: Do I need to purchase other products besides the wind turbine, to produce electricity? Any info about US applications?

A: Yes. To have a running system, the power generated by the turbine (usually wild alternating current from revolutions of the magnetic generator) need to be (1) rectified and (2) transformed in order to be in the “right” voltage for your retail appliances.

For grid-tie installations, this is done using an inverter. State- of-the art inverters usually do both of the above jobs in one box and are designed for direct connection to your breaker box.

Inverters and other items for grid connection are usually sold in two variants. On this website, we are talking about the UL-approved 120V/60 Hz U. S. versions or 230V/50Hz EC-approved versions for Europe, Australia, New Zealand, South Africa etc.

  • Q: How much does a typical system cost, how ong is the payback time?

A: Taking a typical example of a small 1000W micro turbine the following parts-only prices should provide a ballpark figure: $2150 for that 1000W turbine itself, $1300 for a grid-tie inverter e g SMA WindyBoy, min $300 (to $900+) for mounting materials (or a sufficiently high guyed mast of approx 35+ ft), plus over-voltage regulators, cables and other small parts depending on your individual situation.

Given a total of roughly $4500 and an annual output of 1400 to 2300 KWh (in a typical U. S. class 3 or class 4 wind area) including the currently available 30% federal income tax credit, you might expect a payback period of roughly 9 years.

Further state or local incentives or Green Energy Programs will lower this period further, as will the upcoming U. S. feed-in tariffs that are expected at state level in the near future.

(Please note: this is only a very rough guide, as a question submitted that general is hard to answer w/o having further details on the individual situation.)

  • Q: I do not want to attach a turbine to my house. So besides a tower and turbine, what do I need? My appliances need to more or less run 24 hours a day…

A: In order to make a system run 24/7, a way of storing electricity is needed (as wind itself, unfortunately, is not guaranteed 24/7). Storing electricity is usually done using batteries but these are costly and environmentally detrimental — batteries also store only around 70% of the energy ‘stuffed into’ them and lose up to 50% of that on top, so you may end up with as little as 35% to 50% efficiency on the battery portion.

This is why a different solution might be considered, although this would mean losing the “appeal” of a fully independent or off-grid home. Where constant availability is mandatory, a ‘direct-hook’ to the grid would be desirable where you (still) buy power from the grid but feed out excess power back to the grid (if net-meteering or a feed-in tariff happened to exist in your area). You would, then, on balance or virtually run your home appliances on your own home-spun power, i e producing roughly as much as you consume in your home.

In most systems, you would normally need an overvoltage protection and an inverter to convert your MWT power to stabilized socket-grade electricity (120V/60Hz in the U. S. or 230V/50Hz in Europe etc).

  • Q: Could you kindly give a comparison of your system to the double helix system of home wind power generators. I have been hoping to find a system that combines art, color, wild life protection and good efficient engineering design in one package. (submitted by Adelle Jang)

A: The system you mention seems to be a Vertical Axis system. We only have one very small VAWT among our offerings (50 W rated capacity). Reason: VAWT are still mostly in an experimental stage, many horzaontal modesl are already… tested and …proven. Among them this http://www.miniwindsystems.com/?page_id=210 (“Airdolphin” — frankly, our least-favored one in some aspects, because it’s actually VERY efficient engineering, on one hand, comes at a HEFTY MANUFACTURER LIST PRICE on the other)!

Wildlife protection is, actually, not much different between VAWTs and HAWTs: even a small horzontal (propeller-style) turbine is (a) seen by birds and (b) heard by birds and bats and can therfore be avoided. Existing residual casualties among them DO also occur with windows, cars etc, and such residual fatalities cannot be avoided anyway. (Cars and conventional power etc poses a far more significant risk to bird and bat populations than a small turbine when the IMMEDIATE shift toward Green energy is done in due course and not postponed till the point where climate change severely affects animals, plants, and all of us.) Geese have been killed in the LaGuardia/Hudson river plane accident too, but aircraft are still not outlawed.Though I admit that I wouldn’t want to die in a trubine (of any design) the way some animals continue to do, that “wildlife argument” is sort of counter-productive when bearing the big picture in mind, for it means humanity would continue on that rotten energy path of coal, nuclear and oil which has to be left RIGHT NOW.

Art & color are also incorporated into “Airdolphin” with different colors available as a premium feature, see http://www.miniwindsystems.com/?page_id=210

I apologize for only comparing every of your points (above) to that Airdolphin model. I did this because it comes closest to most of the issues you raised. I am, actually, not overly into only touting our own products and would rather consider a broader approach but I, obviously, do not have so many details at hand for some other products I, quite hoestly, don’t know the first thing about — and it would be dishonest of me to pretend otherwise. We do, however, offer a broader view of thing on http://www.miniwindsystems.com/ where we publish a selection of wider news on the subject (whether or not the items are offered at this time or not). You may want to have a look there, too. We are trying to sell products, but we do so because we are also idealists and enthusiastic about the opportunities for (necessary) change available on this basis.

We are very much in favor of helix-style systems and VAWT in general and we are already working on that subject in order to come up with a feasible VAWT solution in the future. As this may take some time (1.5+ years at the very least), we recommend going for existing models for the time being.

Also, incentives programs (tax breaks, government subsidies or even FITs) are available NOW, and as always with fiscal programs, they can be chnaged anytime, even retrospectively (this would even be constitutional in the fiscal policy field)! So this might be a further incentive of ‘taking the money and run’ (and also let your own system run) as soon as possible — on top of the actual benefit of avoiding new carbon emmissions today and not tomorrow.