The renewable power of ocean waves

We know about solar energy and wind energy but one company in California, Calwave, is harnessing the renewable power of ocean waves to produce both electricity and freshwater. As part of our ongoing series of reports Peril and Promise: The Challenge of Climate Change, Calwave co-founder Marcus Lehmann joins Hari Sreenivasan via Google Hangout.


We know about solar energy and wind energy, but one company in California, CalWave, is harnessing the renewable power of ocean waves to produce both electricity and fresh water.

As part of our ongoing series of reports, 'Peril & Promise: the Challenge of Climate Change,' CalWave co-founder Marcus Lehmann joins me now via Google Hangout.

Marcus, thanks for joining us.

First of all, explain what CalWave does.

Yeah, thanks for having us.

And we're developing a new technology that is similar to the offshore windmill, but uses the power of ocean waves to generate electricity.

And as a second application, we're looking into desalination for freshwater production.

Well, harnessing the power of a wave has been around for a while, but how do you figure out where to put this, and what kind of an object is underwater that creates this energy?

Yeah, so that's really our big innovation, that we're able to harness the power efficiently so that's one criteria.

But at the same time, we can also survive storms really well.

And that's what we found were exactly the two features that a windmill needs to survive and operate and be commercially competitive.

And, yeah, we've implemented similar features into our design.

One of the things that I've seen is this idea of a wave carpet.

Is that the core product?

So that was our initial technology.

We started as a shallow-water design, close to shore.

That's also based on the research here conducted, and then based on that initial concept, we further developed it as part of the U.S. Wave Energy Prize.

So the Department of Energy started a nationwide competition similar to the XPRIZE, and, yeah, we've been competing in that for two years and advanced quite well.

So, give me some idea of how much energy you can generate with this wave carpet on a per-square-meter basis, or how it compares to, say, solar or wind on the land?

Yeah, so, we see that one of the advantages of wave power is actually that it's not competing directly with solar and wind.

It's more complementing.

And I think in the future, we need the mix of all renewables available, and so wave power can contribute with a resource that is more predictable.

That means the utilities and the consumers, they can plan better ahead.

With solar and wind, it's very volatile.

That means any other second, the wind can change, and so we need a lot of storage or a very fast ramp-up of gas power to complement that.

So that's the first one -- It's really the predictability.

The second one is the energy density, as you mentioned.

So, on average, the climate we're targeting at the moment has 50 to 60 kilowatts per meter of coastline in California and Oregon, and other locations like Hawaii.

And so that gives an advantage that compared to a windmill where we say a square meter of wind has one kilowatt, yeah, we require less land and hope in the long run, actually, to also become less carbon efficient, or less carbon impactful, because of the pure energy density of waves.

And what about the fact that so many populations live near water?

And usually one of the big challenges is getting the power from the wind turbines to the cities where people live.

Yes, so, we see the fact that we are fully submerged allows us to be closer to the load centers, and we found in the U.S., actually, half of the population lives within 50 miles of the coastline.

That means having a technology that can be close to the big load centers on the cities like San Francisco or L.A.

and the other coastal cities and the West Coast, that gives you great advantage because the cable costs are going to be lower.

And also transmission lines are not needed.

So, one of the concerns people always have is what's the impact on the ecosystem where these things are placed?

Whether it's a wind turbine and the birds that might be affected or solar panels and what happens to grazing lands?

What happens underwater if you're putting out these wave carpets or other devices?

Yeah, so, I would say our structure and the structural impact can be compared to other existing offshore structures.

So, as you mentioned, windmills, they have fast-moving blades, and they're not used to it because that normally doesn't happen in nature.

So they can't see them.

They just fly through it and think there's no obstacle.

In our case, we're moving with the water particles, with the wave motion.

So the mammals can actually see it.

It's like a pier, you would say.

So they're able to notice it and pretty much navigate around it.

But where are you in terms of the competitive landscape?

Are there are lots of other companies trying to harness wave technology now?

Yes, it was actually quite interesting.

It is an early-stage industry compared to wind and solar, but we're moving forward quite well from the concept phase to a demonstration phase.

So there are multiple test sites.

The U.S. actually just awarded a group in Oregon to implement a 40 million test site that is planned to go online in 2020, exactly to facilitate this demonstration phase.

And that's a very critical step for us, because that's how we can prove the cost competitiveness of this technology and how we can operate it.

So, what's the best-case scenario?

Let's say five years from now, if we're having another conversation like this, you're standing in the gleaming giant lobby of CalWave.

What do you hope happens, and how do you see this technology rolling out?

Yes, so, for us, the next phase will be demonstrating the technology before we really provide it as a solution to the market.

And an ideal scenario in 5 years is that we can co-locate offshore wind and offshore wave sharing infrastructure, sharing installation, reducing the costs for both technologies.

And also kind of utilizing the cable connection, interconnection at its most efficiency, and, yeah, I think there are great challenges -- I mean, there are still challenges ahead, but it's a huge potential where multiple offshore technologies can collaborate.

All right. Marcus Lehmann, co-founder of CalWave.

Thanks for joining us.

Thank you so much.