38 May/June 2022
Machines
9COURTESYPLASMAKINETICSto achieve these high pressures. Plasma Kinetics
claims its process provides the same storage den-
sity as 5,000 psi compressed hydrogen gas but
without compression—eliminating pumps, com-
pressors, and chillers.
The company uses a light-sensitive, film-like
“nano-photonic” material to absorb hydrogen,
wound in thousands of layers inside a large can-
ister. Each extremely thin layer has a lattice
structure that binds hydrogen and prevents other
elements from interfering with its absorption.
The company’s process begins by connecting a
hydrogen production “buffer tank” (into which
electrolyzed or steam-reformed gas initially goes)
to a hood with input and output pipes sitting atop
a 20-foot container, which holds 70 canisters of its
nano-photonic film.
On command, H 2 is released from the buffer
tank through the hood into the main container
holding the 70 canisters. When a canister recog-
nizes the presence of hydrogen gas, a valve inside
opens, allowing gas to f low inside. The negatively
charged nano-photonic film has a strong affinity
for positively charged H 2 , absorbing it in minutes
at simple atmospheric pressure.
“If you can provide 10 kilotons of hydrogen per
hour to a Plasma Kinetics system, it can absorb all
10 kilotons,” Smith says. “It’s just a matter of how
much you want to scale.”
Regardless of the source, the result is H 2 stored
in a solid state, according to Smith. The company
anticipates 28 kg of H 2 per cubic meter in 2023
without the need for pressure or energy to store
the hydrogen. That could be useful in challenging
batteries, a relatively dirty technology: Plasma
Kinetics claims that its storage film and housings
require no rare-earth elements.
By the end of 2023, it will have a prototype
demonstration facility completed. Among those
eager to see it will be Steve Christensen, a research
scientist at the National Renewable Energy Labo-
ratory in Golden, Colorado, who has extensively
studied hydrogen storage and cautions that there
are hurdles to its adoption.
Utilities and their investors, Christensen says,
lack understanding of H 2 storage and are com-
fortable with current utility-scale battery energy
storage systems. And because they’re unsure
about the potential cost savings that H 2 offers
through bypassing the need to compress, cool,
and/or liquefy hydrogen, utilities are reluctant to
pass the cost of investing in new energy storage
to customers.
“Is that actually as important a driver in the
cost of the technology as we might expect? It’s
hard to g uess now if it will be cheaper” than exist-
ing systems, Christensen says.
Smith says his movie projector–like system
is nonetheless competitive and will get better as
fuel- cell tech improves. He estimates that the
price of hydrogen when using the Plasma Kinetics
system will be less than $3.00 per gallon-equiva-
lent, while hydrogen is currently sold in California
for $16.51 per gallon-equivalent as of March 2022.
Plasma Kinetics still faces skepticism, and
likely opposition, from entrenched battery inter-
ests. Smith acknowledges the long slog, and that
much remains to be proven. But by force and by
circumstance, he’s slowly dismantling the stack
of challenges of hydrogen energy storage.
“I just took it to the next step in the same man-
ner we do in microchip manufacturing,” Smith
says.“You design [H 2 storage] in layers, and each
layer affects what it needs to affect.”Apples-to-apples efficiency
comparisons among gas-powered
cars, electric vehicles, and fuel-cell
cars are tough. Here’s a quick look
at how they stack up.GAS-POWERED
CARS
A typical gas-
powered car
achieves a 400-
to 500-mile range
with a 20-gallon
gas tank that
weighs 122
pounds full.TESLA MODEL S
The latest Model S
delivers a 390- to
412-mile range
with a 1,200-pound
electric battery
pack, housed across
16 modules: two in
the front, 14 on the
bottom of the car.FUEL-CELL CAR
Plasma Kinetics
says it could deliver
a fuel-cell car with
a 400- to 500-
mile range with a
20-cassette/fuel
cell combination
weighing 794
pounds.HYDROGEN VEHICLES VS.
ELECTRIC CARS