Aryana Nakhai: When we think about the ocean we likely think of summertime and the beach,
but what we may not immediately think about is the amount of potential there is for harnessing
clean energy from the ocean.
We call this marine energy.
This video will cover what marine energy is, why it's important, types of marine energy
resources and technologies, some considerations and challenges, and how researchers at NREL
are actively working to address these challenges.
Where there are bodies of moving water there is energy, and the movement of water creates
a vast amount of kinetic energy that can be harnessed to generate power.
There are several marine energy resources that are distributed throughout the United States,
providing unique opportunities to different states and regions.
Marine energy is a type of renewable energy derived from waves, tides, ocean currents,
free-flowing rivers, and manmade channels.
So, what are some of the opportunities and benefits that marine energy can provide?
Levi Kilcher is a water power researcher at the National Renewable Energy Laboratory.
Levi Kilcher: Marine energy is a super exciting technology because the resource is immense.
Wave energy is a massive resource that exists along the entire US coastline, especially
along the West Coast of the US.
Tidal energy, which you can think of basically underwater wind turbines, is another technology
that has a massive resource and has a lot to offer.
And some of the things that make these technologies particularly exciting is they're very forecastable and predicatble.
We have satellites that are constantly measuring the waves, and so we can see the waves propagating
across the ocean.
We know where they're going to go and so we can plan for that energy to arrive on sort
of weekly or daily time scales.
Marine energy, I think, is especially exciting because it complements other renewable energy
sources in terms of the time of year and the time of day that energy can be provided.
It's also right there on the coastline where a large fraction of our population lives.
And so, these are just some of the examples of why marine energy is so exciting and so promising.
Aryana Nakhai: You may be wondering how do marine energy technologies work?
In a nutshell, marine energy devices capture energy from the movement of water
and convert it to electricity.
That electricity can be transferred via underwater power cables.
There are lots of different marine energy technologies that are being developed to test
and measure different ways to capture our ocean's massive amounts of energy.
The point absorber is one type of wave energy device that floats on the surface of the ocean, like a buoy.
The ocean waves make the buoy move up and down – or heave – in an oscillatory motion.
This motion creates the relative motion needed to convert the energy in the waves into power.
This is an example of a tidal river or ocean current turbine.
These turbines are similar to traditional wind turbines, but instead, the kinetic energy
of the moving water is captured by spinning blades facing the direction of flow instead of wind.
These devices are submerged and anchored at the bottom of a riverbed or ocean.
As the current flows, it spins a turbine and generates power.
Levi Kilcher: Marine energy technologies like wave and tidal energy are at a very early
stage of technology development.
Tidal energy is a little bit farther along.
We're starting to see successful demonstration projects of single devices and we're at the
point now where we're ready to scale that up to larger arrays of devices, whereas wave
energy is at a much earlier stage.
We're still testing single devices, trying different types of concepts, and really just
trying to figure out what's going to work.
The energy, once you have a device in the water, is free.
But building that device, operating it, and maintaining it, all that costs money.
And so, in marine energy we have these big questions about how we're going to get these
costs down because working in the ocean is an extremely challenging place.
And you also couple that with wanting to take care of the environmental impacts of your technology.
You don't want your technology to have unintended negative consequences on the environment.
Aryana Nakhai: The National Renewable Energy Laboratory performs research and development
as well as economic analysis to inform future research and provide data to accelerate the
development of marine energy.
NREL researchers collaborate closely with the wave and current energy communities to
provide expertise in computer modeling and simulation, laboratory testing, and open water
validation to enhance the development of marine energy technologies.
Michael Larson: This is a really exciting time to be a researcher in marine energy.
The industry is at such a nascent stage of development where there's many technologies
out there that have the potential to become commercially successful, and it's just really
fulfilling to get to work with those companies and innovators to understand and develop the
next generation of technologies that ultimately will become our commercial energy solutions in the future.