ORLANDO — Wind energy already accounts for about 5 percent of U.S. electricity generation, which crowned the nation as the global leader in wind production late last year. There is now more than 65 gigawatts (GW) of capacity in 39 states, but according to a new report
from the U.S. Department of Energy (DOE), wind should easily have the
potential to be installed in all 50 states.
How can the industry
accomplish this? Easy. Just follow Germany’s lead and install turbines
with taller hub heights. The U.S. currently installs turbines with an average hub height of 80
meters, but if it increases those heights to 110 meters, which is
commonly found in Germany and other European countries, the potential
output from wind turbines increases by 54 percent. Even more exciting,
if the U.S. uses 140-meter turbines, potential increases by 67 percent.
This may lead to entirely new markets in areas where wind was previously
mostly ignored, like the Southeast.
Light blue coloring identifies land area that meets the capacity
factor threshold today but sees an increase in the proportion of the
area able to achieve this threshold as a result of turbine and hub
height improvements. Orange coloring identifies new land area able to
achieve the minimum 30 percent net capacity factor level as a result of
turbine and hub height improvements. Credit: DOE 2015.
The report inspired wide discussion during a panel session at
Windpower 2015. Jose Zayas, director at the U.S. Department of Energy’s
Wind and Water Power Program, said that higher hub heights allow
developers to see the industry in completely new ways. “Higher heights
equate to better, more behaved wind, which gave us confidence to look at
110- to 140-meter hub heights,” said Zayas. “It is conceivable to see
wind in every state of the union.”
These new opportunities could make wind economical in areas where it
was not four or five years ago, said Paul Gaynor, executive vice
president of North America Utility and Global Wind at SunEdison, which bought First Wind late last year
and has been scooping up megawatts of projects since. “This is a great
opportunity to think about the country a little differently. It opens up
great areas with existing transmission, and if you can exploit these
areas it might make wind farms economic all of a sudden.”
Installing turbines at these heights may even open doors for cost
reduction, according to GE Power & Water’s CEO Anne McEntee. While
wind turbine costs have come down nearly 60 percent in the last few
years, there is still a lot of research and development to further
reduce costs. Just last year, GE introduced its Space-frame tower
that uses 50 percent less steel than traditional towers of the same
height, and can also be shipped in standard shipping containers, rather
than the oft-difficult methods used for traditional turbines. The tower
can also reach 139 meters, which could be ideal for these new prospects.
“Advancements like this are continuing to drive costs down,” said
McEntee.
Karen Conover, vice president of DNV GL agreed, stating that larger
hub heights can lead to even more advancements in other areas. “[Taller
turbines] enable technology improvements in other areas like rotors —
there are lots of improvements we can make,” said Conover. “We need to
shift focus from increased capacity turbines to efficiency, to whole
plant design and performance, to interacting with the grid.”
http://www.renewableenergyworld.com/articles/2015/05/higher-wind-turbine-hub-heights-higher-us-development-opportunity.html