City lights of India are visible from space in this November 12, 2012, image by the Visible Infrared Imaging Radiometer Suite (VIIRS) on the Suomi NPP
satellite captured this nighttime view of India. (Credit: NASA)
There goes conventional wisdom…again.
Turns out that an intelligently
designed, renewably-powered electric grid with storage technology can
juice up a real grid to 99.9 percent by the year 2030 at prices
comparable to today. That's according to a very thorough piece of new
research by researchers at University of Delaware and Delaware
Technical Community College.
To come to this verdant conclusion,
the researchers developed a computer model that sorted through 28
billion combinations of renewable energy sources and storage systems.
Each combination was tested over four years of real historical hourly
weather data and electricity use in a real regional grid that
represents one-fifth of the United States' entire electric grid. So
these folks appear to have been doing everything possible to make
their study realistic as possible.
“These results break the
conventional wisdom that renewable energy is too unreliable and
expensive,” said the study's co-author, Willett
Kempton, of the University of Delware's College
of Earth, Ocean, and Environment, in a press release. “The key
is to get the right combination of electricity sources and storage —
which we did by an exhaustive search — and to calculate costs
correctly.”
The right mix includes a combination of wind power, solar power
and storage in batteries and fuel cells, the researchers report, and
would nearly always generate more electricity than needed without
raising energy costs.
And surprisingly, more storage is not the key
to this renewable grid. Rather, the researchers found that generating
more electricity than needed during average hours would be cheaper
than storing excess power for later high demand. That's because
storage is expensive and batteries or hydrogen tanks have to bigger
for each additional hour of stored electricity.
“For example, using hydrogen for storage, we can run an electric
system that today would meet a need of 72 Gigawatts (GW), 99.9
percent of the time, using 17 GW of solar, 68 GW of offshore wind,
and 115 GW of inland wind,” said co-author Cory Budischak, of
Delaware Technical Community College.
In other words, you need a
higher renewable energy capacity than traditional power generators,
because wind and solar do not generate at their full capacity all of
the time.
There are loads of more details in the
study itself, which is in the Journal of Power Sources. But
the take away message is clear: A renewable grid can be done. It just takes some smarts.
