Large Wind Generator vs. Array of Small Ones

The only possible advantage would be the cost. The larger wind generators can produce more power with lower wind speed (longer blades - lever action,) but are much more expensive.

There are a few disadvantages and problems with putting them on transmission towers; The blades will cause reflections and vibrations, and the generators will cause electronic noise that will interfere with the transmissions.

To repair the wind generators, you have to shut down the transmitters.

Maybe if you used the back up towers, or old obsolete towers it would be feasible.

If you do not need the height of a current transmission towers, you could break it down into 2 towers.

Three main points will cause problems with this idea.

1) The existing transmission tower structure is not designed to support the weight.

2) The turbine blades need to be parallel with the transmission cables to prevent (among other things) accidentally hitting them. There is no guarantee the wind direction will be perpendicular to the turbine blades.

3) But the main problem is overall generation efficiency. The wind farms are built in specific areas for a reason. There is little point putting wind turbines in areas that won't produce high average wind speed, you will never be able to get the turbine to produce enough power during its life to break even with the energy and materials necessary to make it in the first place.

Small turbines mounted on the top that could be turned into the wind are a potential possibility, but then you are likely going to need an additional transformer to step up the turbine generator voltage. They also won't be a very efficient way of producing the power (and will look very ugly). I cannot see this being an acceptable practice over building existing large turbines and high towers.

Hi,

if we want to make a success of wind power we will have to go up further.

As wind speed increases with height there is little doubt that we need the big ones.

Force times velocity is power.

Maximum obtainable force is mass-flow times velocity.

Mass flow is density times velocity.

So power is ~ velocity³

We cannot waste this.

Size will be limited by material strength.

Skyscrapers have shown that 500m is possible, so will do wind-generators.

And wind-generators are going offshore: wind-speed is much higher, cabling cost and building and maintenance cost is much higher, but vast good areas available. Success will depend on reliability and survivability in severe winter-storms (in Europe) and tropical storms elsewhere. I do not expect to see these in hurricane regions.

This is a chance to make this technology really a good investment.

Today this is only experimental tax-payers money burning.

RHABE

For me it is a good idea, I'm thinking of it myself.

Why don't we put them on the lighting poles along highway's?

A bit stronger pole and you can put a 30 KW vertical axis turbine every 30m.

Vertical axis turbines have lower noise problems.

Highways usually have a bit of free space which will enable the wind to gain in power.

After all it is the political will.

Hi,

this would be great,

what size estimate do you have: diameter of mast, height, propeller?

30KW at peak wind or at 5m/s?

Estimated cost (single units today)?

Estimated maintenance cost?

Estimated KWh/a generated?

Thank you

RHABE

But most poles close to highways have to be "break-away" poles for transportation safety reasons. Increasing the strength to carry the loads of the turbine would make this difficult.

This is a requirement which is indeed adopted for poles which are hit more than once.

99% of the poles is never hit and when the oil is out they will never be hit anymore.

The power poles will save more lives than they will cost due their enhanced rigidity. Only difficult to measure.

To learn more about small size wind power electric generators, visit www.youtube.com, then search for "Hong Kong wind generators." Then look at "Motorwind Turbines at Sea School, Hong Kong" and "Wind Turbines offer cheap energy."

Friends,

Consider the advantages and disadvantages of each approach:

Many small units: + Easy to erect, + Production volume gives decreased unit costs, + Less visual disturbance from a distance, + Greater diversity of units for increased stability of system and decreased risk of system harm from unit failures, - Reduced efficiency, - Reduced wind speed (because of typically lower mounting height), - Increased maintenance because of more units.

A few large units: + Greater efficiency, + Higher wind speed, + Reduced harm to flying birds, - Greater damage risk if blades fail, - Objections to visibility on skyline.

I suspect that the specific site's conditions will influence the choice of turbine size and mounting height; and that the optimum choice for each installation can be different. However, I also suspect that standardization of sizes and designs will give significant long-term savings and allow large unit manufacturing, installation, and operating costs to be lower per installed kWh than those for smaller units.

Regards, --John M.