Energy Towers Touted as Future Source of Electricity
By Stuart Winer September 14, 2003
From giant energy towers to new solar power units, alternative forms of
energy came to the forefront last month at a joint Israeli-U.S.
conference in Jerusalem. And the participants, including senior
officials at the U.S. Department of Energy, said they duly impressed by
Israel's innovations that will help generate news forms of electricity.
When President George W. Bush delivered his state of the union address
in January 2003 he called for energy revolution as a national target for
the United States. "Our third goal is to promote energy independence for
our country, while dramatically improving the environment," Bush said.
The energy requirements of Western countries largely fall into two
categories: powering vehicles and generating electricity.
The conference - called Cooperation for Energy Independence of
Democracies - kicked off with the first ever demonstration of a
commercial hydrogen fuel cell in Israel. The cell, slightly smaller than
a desktop computer, generated enough electricity to run a laptop
computer using hydrogen from an attached gas cylinder.
Former US senator Rod Grams, addressing the conference, stressed the
importance of energy independence to both Israel and the United States.
"We have faced energy crises and Israel has no natural energy resources
of its own," Grams said. "By gaining independence we lessen the chance
of energy being used as a weapon. Israel does have brain power, so let's
turn that into energy."
The choice of location for the conference was significant according to
various speakers. The Honorable Admiral (ret.) Thomas J. Gross, US
Deputy Assistant Secretary of Energy, who attended the conference, said
"Israel is a superior location for technical and scientific talent."
Whereas hydrogen fuel cells, which generate electricity from liquefied
hydrogen gas, are seen as the future replacement for gasoline and
diesel, conference participants learned that a variety of methods are
being investigated in Israel as alternative, renewable methods of
Israel, as a desert country, is one of the world leaders in the field of
solar power and local companies used to conference to show what the
future holds in power from the sun.
"A square yard of desert absorbs as much energy over a year as you can
get out of a barrel of oil," says Professor David Faiman, of the Ben
Gurion University Solar Energy Center.
Producing the hundreds of megawatts of energy required by communities in
developed nations requires vast areas of desert covered with solar
However, research by Israeli companies is working to improve efficiency
of solar systems.
Barbra Shaw, marketing manager for Solel, a Beit Shemesh based company
says that the turbulent energy supplies in California and the southwest
of the United States, coupled with world events over the last two years
shows that it is time to develop solar power sources. Solel took over
Luz, a solar company that set up solar power units in California nearly
20 years ago. The units use 'troughs', rectangular mirrors with a
parabolic curve that focuses the sun's rays to provide energy.
Today the company has nine plants in the Mohab desert, operated by three
different local power companies. Between them, the solar plants, which
cover an area of 500,000 square meters provide over 350 megawatts of
electricity to half a million Californians.
That output, says Shaw, is about to get even better. By improving the
technologies of the heat collecting panels the company hopes to increase
power output by up to 20 percent.
"That is very significant," Shaw says. "It means the size of the plant
can be smaller which brings down set-up costs.
Solel's expertise is in the coating of a heat collecting glass element
that runs the length of each parabolic mirror. Reflected rays from the
sun heat the oil which is used to turn water into steam to power
"What makes it so efficient is the coating on the glass," Shaw says.
Solel is also developing technologies to use solar power for
Hot water at 100 degrees centigrade passes through an 'absorption
chiller' where a chemical process turns the hot water in to cool air.
"It is like an air-conditioner with out a compressor," Shaw says.
Solel is now posed to build larger, more powerful plants. The company is
seeking to form alliances with American companies in order to build five
100 megawatt plants in the southwest United States.
The problem of providing power at night or in winter is can be solved by
have a natural gas back-up source.
"A solar thermal power plant is like a regular plant just its fuel
source is the sun," Shaw explains. "It has turbines that produce
electricity. For night or winter you can change the energy source to use
However, one group of researchers at the Faculty of Agricultural
Engineering, Technion-Israel Institute of Technology is taking an
entirely new approach to generating electricity: Energy Towers.
The idea is the brain-child of Professor Dan Zaslavsky and makes use of
the convection of air through a hollow tower to turn turbines. Cold
water droplets sprayed into the top of tower evaporates cooling the air
which then sinks to the bottom of the tower and turns the turbines.
Zaslavsky claims that forty such towers could generate enough
electricity for the whole world, not just today, but for the foreseeable
The team set up Sharav Sluices to promote the idea and Doctor Rami
Guetta, project manager says the company is already in negotiations to
build a 10 megawatt tower in India. Other countries that have shown a
serious interest are Australia, Chile, and a French engineering company
that is interested in providing the mechanical infrastructure for the