Friday, March 1, 2013

Sizing up wind turbines: How big are they?

For those staying nearby a wind farm, the mighty tall hub with giant fan blades may be your familiar view. But for the rest of us, here is how to get the hint of how big is a standard 1.5MW - 2MW wind turbine.

Study shows that that, the larger the turbine is, the greener the electricity, i.e. smaller carbon footprint. This effect was due both to size of the turbine as well as the learning and experience gained with the technology over time. Currently, as at end-2012, the largest wind turbine is Siemens 6 MW (megawatt) SWT-6.0-154 offshore turbine in Denmark.

Siemens 6MW wind turbine is the largest to date
Siemens 6MW wind turbine Specifications

Type                    : 3-bladed, horizontal axis
Position               : Upwind
Diameter              : 154 m
Swept area           : 18600 m²
Speed range         : 5-11 rpm
Power regulation : Pitch regulation with variable speed
Rotor tilt               : 6 degrees

Type                        : Self-supporting
Blade Length            : 75 m (B75)
Aerodynamic profile  : Siemens proprietary airfoils
Material                   : GRE
Surface gloss           : Semi-gloss, <30 / ISO2813
Surface colour          : Light grey, RAL 7035

Hub height      : Site specific, could be up to 130 m

The giants are getting bigger!

However, current trend is that wind turbines are getting bigger. In January 2013, British company, Blade Dynamics, announced it was developing blades of up to 100 meters in length dwarfing the size of existing Siemens 75-meter turbine blade. Sitting on top of a tower 170 meters high, the structure will be 270 meters in total.

In comparison, KL Tower stands at 421-metre high while Petronas Twin Towers at 452 metres. So, when completed, Blade Dynamics' 270 metres structure is pretty tall.

Size comparison

Comparing these turbines with other structures, it is easy to see why many people are protesting against large wind farming due to noise pollution and their unsightliness.

How much power can they generate:

Estimated capacity with good wind, i.e. wind blowing within designed range.

Researchers say that bigger wind turbines are more cost effective, but there should be limit somewhere when the cost of building the towers are more that the selling price of electricity generated.

Let's hope they are not near your home.

References (image credits and facts):

1) Wind turbine with the world's largest rotor goes into operation - Siemens
2) Wind Energy - The Facts
3) Solvent Green - Windfall
4) Siemens 6.0 MW Offshore Wind Turbine

1 comment:

thomas said...

Wow!That's huge,things like this need to be maintained by the OEM
or else we will get something like
that in Perhentian Kecil.