The world's oceans are a vast untapped energy
resource. Waves off the coast of the U.S.
could theoretically generate 2.64 trillion
kilowatt-hours of electricity per year.
That's about 64% of last year's total utility scale
electricity generation in the U.S..
We won't need that much, but one day experts do hope
that wave energy will comprise about 10% to 20% of
our electricity mix.
So wave power is really the last missing piece to help
us to transition to 100% renewables.
But while scientists have long understood the power of
waves, it's proven difficult to build devices
that can harness that energy.
So the ocean is a challenging, challenging
environment to work in. It's a challenging
environment to build infrastructure in.
It moves sometimes violently.
It's corrosive.
Now though, an influx of federal funding is helping
many U.S. companies gear up to test their latest wave
energy converters. As the nation's first full-scale
grid-connected test facility for these
technologies, called PacWave, is set to come
online over the next few years.
PacWave really represents for us an opportunity to
address one of the most critical barriers to
enabling wave energy, and that's getting devices into
the open ocean.
That will help the U.S. catch up with its European
counterparts, who've been testing wave energy devices
off the coast of Scotland since the early 2000s.
But while many prototypes have been developed, it's
still unclear what technology will prove viable
for grid-scale electricity production.
There's just this vast array of approaches to turning
oscillatory motion into ultimately electrical power.
We spoke with a number of companies pursuing different
technologies and learned how this emergent energy
source could help us transition to an
all-renewable world, if we can get it to work at scale.
Besides the fact that the ocean is a rough
environment, the very nature of waves themselves
means harnessing their energy is much less
straightforward than say, wind or hydropower.
Winds and currents, they go in one direction.
It's very easy to spin a turbine or a windmill when
you've got linear movement.
The waves really aren't linear. They're oscillating.
And so what we have to be able to do is turn this
oscillatory energy into some sort of catchable form.
There are a number of different ways to do this,
but generally speaking, devices work by harnessing
the up and down, back and forth or rotational motion
of the waves to drive a generator to create
electricity. Some companies are now attempting to
harness energy from multiple different modes of
motion.
And what we don't really know is which of those is
best in a real world, full-scale system.
One technology might work really well for large, slow,
open ocean swells. Another technology might work really
well for choppy or wind wave kinds of energy.
If wave energy proves to be scalable, it has the
potential to be an excellent complement to wind
and solar, since it can produce energy 24/7 in all
weather conditions. And while wind and solar
production peak in the spring and summer
respectively, waves are more powerful and consistent
in the winter. But the infrastructure required to
scale up any of these systems and connect them to
the power grid is complex and expensive.
So if you're building, let's say, a wave energy plant
offshore, you're going to have to build your mooring
and anchoring systems offshore. Cables will then
go from your wave energy converter down to a subsea
cable where you'd probably have a sort of a junction
box where you might plug 10, 20, 50 devices in with
one larger export cable that will then run along the
seafloor. But when it gets close to shore, you'll have
to drill it under the seabed, under the surf zone,
because that's a very active environment.
And then pop up in a location onshore.
PacWave, the Department of Energy-funded wave energy
test site off the Oregon coast, is building this
infrastructure now. It's a collaborative effort between
the DOE, Oregon State University, the National
Renewable Energy Lab, the European Marine Energy
Center, and a host of other marine energy experts.
The facility is fully pre-permitted, so companies
can trial their prototypes without concern about
regulatory delays.
The Department of Energy has funded eight different
companies to start deploying at PacWave
beginning in 2024, and we can't wait to have them on
site. This is really a seismic shift in the wave
energy community.
In the U.S., the DOE has been funding marine energy
for about a decade, a category which not only
includes wave power, but also power generated from
currents, tides, and temperature changes.
During that period of time, we've spent probably around
$500 million or so on marine energy.
But this year we actually saw a record amount for our
office, specifically for marine energy.
$112 million in 2022, and this also includes an
additional $110 million from the Bipartisan
Infrastructure Law. And at the beginning of this year,
the DOE announced $25 million in funding for eight
wave energy projects, which will comprise the first
round of technologies to be tested at the PacWave
facility. Of the eight projects, Bay Area-based
CalWave received the largest amount, $7.5
million. A small-scale version of CalWave's device
recently returned after a successful ten month
deployment off the coast of San Diego.
Yeah, the device we're testing at PacWave will be a
larger version of this, so nearly double the size and
ten times the amount of power. And so this unit
specifically was able to power about 30 households.
The x800, our megawatt class system, produces
enough power to power about 3,000 households.
So our target is 20-year deployments at sea.
And I think that's very achievable with maintenance
interventions about every 4 to 5 years.
CalWave's tech is classified as a submerged pressure
differential device. It operates completely below
the surface of the water, and as waves rise and fall,
surge forward and backward, and the water moves in a
circular motion, the device moves too.
Dampers inside the device slow down that motion and
convert it into torque, which drives a generator to
produce electricity. Lehmann likens it to how
electric cars recharge when braking.
As the electric car goes downhill and you put on the
brake, it would produce power.
And so the waves move the system up and down and every
time it moves down, we can generate power.
That oscillating motion we can turn into electricity,
just like a wind turbine.
Seattle-based Oscilla Power was awarded $1.8 million
from the DOE, and it's getting ready to deploy its
wave energy converter off the coast of Hawaii at the
U.S. Navy Wave Energy Test Site.
While this facility is smaller than the planned
PacWave facility, it's currently the nation's only
grid-connected site for tech like this.
The system that we're deploying in Hawaii is what
we call the Triton-C.
It's about a third of the size of our flagship
product. It's designed to be 100 kilowatt rated, and
it's designed for islands and small communities.
Nair and many others are excited by wave energy's
potential to generate electricity for remote
regions, which rely on expensive and polluting
diesel imports to meet their energy needs.
Oscilla Power uses a technology known as a
two-body point absorber.
Part of the Triton-C floats on the surface and moves
with the waves in all directions, up and down,
side to side, and rotationally.
Underneath the float hangs a large ring-shaped
structure, which stays relatively steady, thus
generating force on the lines that connect it to the
float. That force is then used to rotate a gearbox to
drive a generator.
So under very weak waves we get a lot of pitch and roll
motion in our system. At very strong waves, we get a
lot of surge motion. And in the most prevalent wave
climate, we get a lot of heave motion, that's up and
down motion. So across all of these, the system
certainly moves enough for us to be able to capture
energy efficiently across a wide range of climates.
Oscilla Power plans to deploy a larger,
megawatt-scale device in India in 2024 and then move
on to testing at PacWave.
The DOE also awarded Charlottesville,
Virginia-based company C-Power over $4 million to
develop and test its grid-scale wave energy
converter, the StingRAY, at PacWave.
But before that testing takes place, the company is
focused on commercializing its smaller scale system,
the SeaRAY, designed for lower-power applications.
Think about sensors in the ocean, research, ocean data
gathering. Maybe it's monitoring or inspection.
The next step, Lesemann says, is powering ocean
robotics and operating equipment.
And then you think about diesel gen set replacement
for island power.
Then we start to work our way towards charging
networks for autonomous surface vessels.
And then eventually to terrestrial, to grid
applications.
The SeaRAY consists of two floats and a central body,
the nacelle, which contains the drive train.
As waves pass by, the floats bob up and down,
rotating about the nacelle and turning their own
respective gearboxes, which power the electric
generators.
We have a SeaRAY that will be deployed off the coast of
Hawaii this fall, and that's a two kilowatt
version. We've got a number of customers that are
involved with us. Saab is one, who's one of the global
leaders from a subsea robotics perspective.
Biosonics is another, with a static data gathering
system.
After these initial applications, C-Power will
work on scaling up its SeaRAY so that it's capable
of satellite communications and deep water deployments,
before building a 200 kilowatt StingRAY to test at
PacWave.
The European Marine Energy Center, or EMEC, was the
first test site in the world for wave and tidal
technologies when it opened in 2003.
We've had something like 35 different devices in the
water, from 22 different companies from, I think 11
different countries.
Some of those include Finnish company Wello Oy,
which produced power for the grid in Scotland during
its two deployments at EMEC, and has subsequently
been deployed in Spain, and Scottish company Pelamis,
which became the first offshore wave energy
converter to produce power for a national grid in 2004.
It was also the first to be purchased by a utility
company, though financial troubles ultimately forced
the company to cease operations. Well EMEC has
seen its share of successes and disappointments, no
company has yet commercialized a grid-scale
wave energy converter, so Kermode is more than happy
to see more players and more testing facilities
popping up.
We firmly believe that this is an international endeavor
and we're not going to win this just because some
people on a small Scottish island manage to crack this.
This will be dealt with because the scientific and
technical community has really put its shoulder to
this and found a way to make it work.
But while PacWave and EMEC are focusing on testing
offshore devices, one Swedish company, Eco Wave
Power, thinks it will be quite a while before these
complex devices can reliably produce power.
I would like to see more companies focusing on easier
projects that will give the population, the investors,
the government the safety to say, okay, now it's safe
to legislate, now it's safe to invest, now it's safe to
believe in wave energy.
That's why Eco Wave Power is installing onshore devices
on breakwaters, piers, and jetties.
The only thing in our technology that is in the
water are the floaters which belong in the water.
All the expensive conversion machinery is on
land just like a regular power station.
So basically this enables a very low installation,
operation, and maintenance costs.
As a floater moves up and down with the motion of the
waves, it drives a hydraulic piston, which
compresses fluid that's then stored in an
accumulator. When the fluid is released, it turns a
hydraulic motor, which powers an electric
generator. While near-shore and onshore waves aren't as
powerful as offshore waves, Braverman says that current
technologies aren't able to fully take advantage of that
extra energy potential, meaning the energy produced
from her company's floaters is on par with the offshore
competition. Eco Wave Power produced power for the grid
in Gibraltar for six years, powering around 100 homes
with its 100 kilowatt system, when operating at
peak efficiency. The company is finalizing
another 100 kilowatt grid-connected station in
Israel, and has signed an agreement to install its
devices at the Port of Los Angeles, starting with a 100
kilowatt installation and hoping to scale to 15
megawatts, which could power about 15,000 homes.
There are still many unknowns when it comes to
wave energy tech, including whether costs can fall
enough to become competitive with fossil
fuels.
In order for marine energy to be competitive, we need
to be at cost parity with solar and wind or offshore
wind. So really driving at that less than $0.06 a
kilowatt hour.
But that's a long way away.
The projections for the levelized cost of energy for
the wave energy devices are $0.60, $0.80, a dollar per
kilowatt hour.
Wave energy has really struggled to get solid
deployments at the moment, mainly to be brutally
honest, because hydrocarbons have been so
cheap.
And while there are ongoing efforts by the DOE and the
companies themselves to monitor the impact of their
devices on marine ecosystems, it will take
time to get a full picture of the impact.
Really, this is going to have to be something that we
learn as we put systems into the water.
But we're funding environmental monitoring,
funding work to really understand the interaction
of species with deployed systems.
And we take this very seriously.
Questions about potential environmental impacts could
delay the permitting process as companies move
beyond testing and attempt to commercialize.
One thing that could make permitting easier though, is
if there's convergence around a particular design
principle.
There are different applications that require
somewhat different approaches. But I think for
the mainstream you will see some form factor
convergence.
Right now though, it's far from clear what technology
will rise to the top for grid-scale electricity
generation. But in the meantime, experts say that
there are many exciting low-power opportunities.
Data gathering, subsea robotics, operating
equipment, that's today.
That's ready to go today.
Next, many point to places in the Arctic, like Kodiak
Island in Alaska, as potential early adopters of
the tech, since there's so little solar power there in
the winter and the community relies on
expensive diesel generators for power.
Estimates vary for how long it will take before we see
wave farms providing power to the mainland, but most
agree that it won't be this decade.
So we have a goal of setting about one gigawatt of power
by 2035, and we really see that as the first
opportunity for wave energy to come online to serve the
nation's grid.
Scale up will largely depend upon continued government
support in the U.S. and abroad.
The recent passage of the Inflation Reduction Act,
which includes $369 billion earmarked for clean energy
and climate change mitigation, has many
optimistic. But Kermode says that globally, we need
to be even more aggressive about getting these devices
in the water.
It does take time to do this.
Question is, do we have time? And so do we need to
get at this harder than we are at the moment?
And I would suggest we really, really do need to be
quite aggressive in what we're doing and really push
hard.