a metal, as the energy carrier in
its chemical soup. But the startup
faces two fundamental challenges.
One is supply. Vanadium is a global
commodity with a fluctuating
price. Right now, prices are high,
undermining Vionx’s economics.
The other problem is demand.
Government policies, which shape
the grid-storage market, were writ-
ten to support lithium-ion systems,
which typically can provide about
four hours of backup and which
degrade and need to be replaced
every few years. But Vionx’s
system is sized to be economically
competitive for about 10 hours of
storage—and to last 20 years or
more with essentially no degrada-
tion. The system’s beefiness brings
higher initial capital costs that
pencil out only when amortized
over more hours of electricity sales.
Buying a Vionx system to produce
four hours of juice would be like
buying a blowtorch to light a cigar.
“It’s a big issue,” says Vieau,
reflecting over a dinner of oysters
and fish at one of his favorite white-
tablecloth restaurants in Boston.
It’s also a familiar one. He finds
himself at Vionx today in much the
same dilemma that he did at A123:
with an energy-storage device that
he’s convinced is technologically
ready but that the market doesn’t
want, at least not yet. “The question
is, ‘Can you get to a point where
renewable energy plus storage is
cheaper than coal?’ And the answer
is yes,” he says, sipping a French
Chardonnay. “I’m as convinced
today that this is a reality as I was
in 2004 that the electric car was go-
ing to happen. But the question is,
when is it going to happen?”
V
IONX IS but one of many
grid-storage hopefuls
wrestling with that
dilemma. Another is
Form Energy, a startup that grew
in part out of the laboratory of Yet-
Ming Chiang, an MIT materials-
science professor who worked with
Vieau as the technological mind
behind A123. Form has raised
about $11 million, plus a recent
$3.9 million grant from the U.S.
Department of Energy. Among its
other investors are Breakthrough
Energy Ventures, a $1 billion
clean-energy-technology fund es-
tablished by Bill Gates and a who’s
who of other global billionaires,
and Saudi Aramco, the oil giant.
Form aspires to affordably
produce radically long-term
energy storage—enough not just
for 10 hours but for several days or
even weeks, which its executives
argue will be necessary to reach
percentages of renewable energy
on the grid that really will phase
out fossil fuels. The federal grant
Form won was to build a system
using sulfur as a key ingredient.
Chiang, chatting in his sunny office
in Cambridge, Mass., won’t say
whether the storage device Form
hopes to commercialize will use
sulfur. But, choosing his words
carefully, he says that “sulfur ap-
pears to be one of the most attrac-
tive, earth-abundant molecules.”
Nonscientific translation of “earth-
abundant”: cheap.
A few blocks from Chiang’s
office, I visit Malta, a startup
spun out last year from X, the
skunkworks of Alphabet, Google’s
parent. Like Form, Malta, based
on Stanford technology, plans to
use giant tanks and pumps to store
energy for several days or more.
But its technology aspires to store
energy as heat, an arrangement
it sees as more economic. Malta’s
investors include Breakthrough
Energy Ventures, a Swedish
heat-exchange-equipment maker,
and a Chinese renewable-energy
producer. As if out of a startup
documentary, the company is
based in a shared workspace in
Cambridge where cold-brew coffeeWHEN THE
WORLD’S
MOST
POWERFUL
WOMEN
SPE AK ,
STOP
TALKING.
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