Turbine size: is big always beautiful?
Today’s turbines can be mind-bogglingly big, but big is not necessarily better. Mike Woebbeking, Vice President of GL group and chair of a session at EWEA 2012 in Copenhagen on 16 April that delves into turbine size, tells the EWEA blog that size isn’t everything…
How has the average turbine size changed over the last decade?
Ten years ago the average size was around 1.5 MW, today it is close to 3 MW. Thus the average size of onshore wind turbines more or less doubled. For offshore wind this is more difficult to say. A decade ago there were only very few turbines installed offshore. The average size could be assumed to be around 1.5 MW. Today the average offshore turbine size is below 5 MW, however 7 MW turbines and bigger are under development. The average size of offshore turbines has roughly tripled within a decade.
How big do you think turbines will be by 2020?
In 2020 the average onshore turbine will be 4 MW. The average offshore turbine will be in the range of 12 MW.
What are the pros and cons of bigger turbines?
This is difficult to answer as there are many pros and cons for all existing types of turbines, sizes and concepts and the answer is very much depending on the site, its conditions and the strategy of the project as well as availability of components and turbines, not to mention pricing, capital and operational expenditure.
And how about smaller turbines?
If we are talking about smaller turbines, the benefits are easier ways of installation, availability of these products, building permissions (depending on the market) etc. However the capacity factors are limiting.
What are you hoping to get out of EWEA 2012?
Besides all the networking opportunities we will learn about the history in wind turbine development and challenges of the past, delegates will understand the actual challenges and needs in turbine design of the present as well as take home solutions to face these and last but not least all of us will look into the future and foresee the forthcoming turbine technology.
More on EWEA 2012: www.ewea.org/annual2012
Once SMALL IS BEUTIFUL and now BIG IS BOUNTIFUL!
In the 70s there were designs from NASA and Growian of MW size but they were not successful.
WONDERS OF COMMUNITY PARTICIPATION IN WINDMILL
The TvindMill (Tvind Møllen, Skorkærvej 8, Tvind, 6990 Ulfborg , Denmark) is one of the biggest windmills in the world (54 m). It is an impressive building, constructed by the pupils of the school with the advice of experts.
The construction of the mill started in 1975, and today the mill supplies the many school-buildings with electricity.
There is a lift inside which takes people to the top. It is a tourist attraction. I visited visited the Wind Turbine thrice when I worked in.
Tvindkraft was created to show the way forward for wind energy – and to show the way out for nuclear power. But the most important thing was probably that the Teacher Group showed that it was possible for normal people, without any significant scientific education, to build a large wind power plant. With their determination, their drive, their elbow grease and common sense, cooperation and support, where help was to be found, this unparalleled structure was created – despite comments like: “You are doing wind power a disservice by trying to build a windmill”, and despite the fact that no authority wanted to give any financial assistance to the windmill construction, although it clearly followed the recommendations of the ‘Akademiet for Teknisk Videnskaber’ [Academy for Technical Sciences] to promote the development of wind energy in Denmark, with both practical experiments as well as research projects.
Tvindmill is a Downwind Turbine
Upwind Vs Downwind Turbines:
An Upwind turbine faces into the wind with the turbine blades in front of the Nacelle while a Downwind turbine has blades to the rear of the Nacelle and faces away from the wind. Up-wind turbines are by far and away the most common, but down-wind turbines (usually two-bladed) are also used in certain situations.
Incidentally in India few Downwind Turbines were installed.
Dr.A.Jagadeesh Nellore(AP),India
Wind Energy Expert
E-mail: anumakonda.jagadeesh@gmail.com