Seafloor Carpet Turns Surf’s up to Lights On

At the University of California, Berkeley, a team of engineers is pioneering ocean-source energy technology by using “carpet” to capture the energy generated by ocean waves.

The team, which includes wave energy guru and Assistant Professor Reza Alam, and Ph.D. Marcus Lehmann, an engineering researcher, aims not only to capture the kinetic energy contained in the ocean, but eventually to use it to purify seawater – drinking water being an increasingly diminishing resource on planet Earth.

This is particularly true where ever-growing populations living in coastal cities like Los Angeles demand greater and greater quantities of non-saline water for drinking, bathing, washing dishes and clothing, and for irrigation. (Re that latter, it’s disturbing to know that more than half America’s produce begins life in the warm, fertile and currently drought-stricken Central Valley).

As the United Nations Environment Programme (UNEP) notes, half the Earth’s population (about 3 billion people) lives within about 35 miles (or 60 kilometers) of a seacoast, and 75 percent of the globe’s largest cities are located on ocean shorelines. By 2025, that figure is expected to double.

The reason? Man has, since ancient times, migrated to the edges of oceans to take advantage of the edible wealth of sea life, which is more easily captured by fishing than land-based animals are by hunting. Coastal cities also capitalize on one of the oldest transportation modes known to man, namely shipping (which is less energy intensive than freight trains, trucks or airplanes).

Moreover, the Berkeley team has conducted experiments showing just how energy-rich ocean waves are. For example, less than 11 square feet (or one square meter) of their ingenious “carpet” – which is able to capture more than 90 percent of wave energy – is enough to power two U.S. households, or about 1,800 kilowatts of energy. One thousand eighty square feet, or 100 square meters, would generate the same amount of energy as a soccer field covered in solar panels. And all that energy would be generated in or near the world’s coastal cities, where the energy demand is greatest.

The system itself consists of a network of hydraulic actuators overlaid with a rubber mat whose future composition, presumably a durable and salt-water-resistant elastic composite, remains a secret at this point, according to Lehmann.

The cost of this energy is calculable. The cost of desalination can’t be estimated, since the wave energy project is still in its infancy vis-à-vis wave power conversion and absorption, but in its tertiary stages should surpass current desalination costs (from $.40 to $.90 per barrel in Saudi Arabia). A barrel is 31.5 gallons or 119.5 liters.

In these initial stages, however, Lehmann and colleagues are banking on a report from Carbon Trust which indicates that wave energy could produce more than 2,000 terawatt hours (or a phenomenal 2 billion kilowatt hours, or kWh) per year. This is enough to power two million U.S. homes, each using 1,000 kWh, which is well above the average.

Lehmann and his colleagues have also thought ahead to the environmental and sustainability issues. Unlike offshore wind (notably Cape Wind, the recipient of a $600 million loan that will not make it less of an eyesore from the Kennedy Compound in Hyannis Port, or less of an irritant to gas and oil tycoon, and Nantucket shoreline owner, Bill Koch), wave energy production is invisible.

This is because the project(s) rests about 60 feet under the surface, and in otherwise useless sea floor areas, or dead zones, like the Gulf of Mexico. This, forming at the mouth of the Mississippi River, in Louisiana, is the largest in the world. In addition, such projects will, in no location, impinge upon the visual and physical world dominated by fishing or recreational boating, or sea life.

The Alam/Lehmann team seems to have come upon the perfect recipe for “clean” energy. Still, as a rational person, I know nothing is perfect. Lehmann agrees:

“The exact location is part of our research. The downsides are more material needed for the same absorption efficiency at deeper water locations, and (the fact that) the ideal location will not be directly on the ocean floor to minimize environmental impact, sand erosion and sediment residue.”

Within the next two years, Lehmann anticipates testing the system in the field, in either Hawaii or Newport, Oregon, both of which provide wave test centers. (I expect the team to vote for Hawaii, as who wouldn’t?)

In the interim, Lehmann and colleagues continue to use the wave-testing tanks at UC Berkeley, the results of which were presented at the 10th European Wave and Tidal Energy Conference, Aalborg University, Denmark, September 2013.

One of the biggest hurdles to wave energy, according to Lehmann, may be the fact that each wave energy siting will require different materials, tools, and techniques, from the “carpet” material to the height of the hydraulic actuators.

“The challenge of wave energy is to design specifically for every individual characteristic of the designated wave site. Our system allows a lot of parameters to easily adjust.”

An accommodation which wind and solar seem unable to grant. For example, the Mojave Desert solar project mandated the removal of native (and seriously endangered) desert tortoises. And it’s now common knowledge that wind energy companies have filed at least 14 separate applications that would allow them to kill eagles, albeit inadvertently through turbine blade rotation.

Boeing’s SBRC Makes Biofuel from Agricultural Rejects

A decade ago, biofuels were considered the Holy Grail of combustion-engine fuels.

Measurably cleaner than fossil fuels, they were the proverbial light at the end of the tunnel, at least according to some clean energy experts.

Fast forward to 2008, when the biofuel industry’s withdrawal of food crops such as corn, rice, wheat and palm oil caused a world-wide food crisis that affected almost everyone, but the poor most of all. Prices jumped from 102 percent (for rice) to 204 percent (for corn). Food riots spread from Haiti to Bangladesh, and from sub-Saharan Africa to Egypt.

Closer to home, but no less desperate, the most impoverished residents of Mexico and South America were reduced to eating nothing but corn tortillas, since the cost of the cornmeal precluded also buying vegetables on the little money they could scrape together at the end of the day.

It was Darrin Morgan who said, “Corn ethanol is a perfect example of how not  to do things.”

Morgan, who is the Seattle, Washington-based Director of Sustainable Aviation Fuels and Environmental Strategy at The Boeing Company, is refreshingly blunt. Sometimes that directness seems the only way to reach people bombarded by the deluge of 21st century information sources.

And Morgan’s news is exhilarating: Boeing’s research consortium (Boeing, Honeywell UOP and Eithad Airways; known jointly as the Sustainable Bio-Energy Research Consortium (SBRC) at the Masdar Institute of Science & Technology in Abu Dhabi has found a class of plants that can grow in the desert, on salt water.

These plants, known as halophytes (or xerohalophytes), have been adapted by Nature over thousands of years to survive harsh growing conditions, notably saline water and desert soils. These halophytes are also nearly indifferent to high temperatures and water shortages, making them ideal for the purpose.

Nature also, and perhaps unintentionally, made these halophytes low in the lignites that make plants grow upright and bind their structure. This means that it takes much less energy to extract the highly useful sugars that go into making of superior biofuels – a discovery that seems to be a first, since no one else appears to have patented the process.

The final step of the equation, notes the SBRC, is incorporating aquaculture; the raising of plants and fish in a cooperative, water-based environment. This final stage provides a perfect complement to halophytes, which thrive on fish wastes comprised of the very ingredients found in chemical fertilizers. The entire pilot project fits on a two-hectare plot within the Masdar City limits, and bears the name “integrated seawater energy and agriculture system”, or ISEAS.

Is it sustainable?

“Yes!” says Jessica Kowal, Boeing Commercial Airplanes Environment Communications representative. “In fact, that sustainability awareness is what a colleague of mine called ‘the triple bottom line; economic, social, and environmental.”

Kowal also reminds me that Boeing has other partners around the globe, most recently with South African Airways, or SAA, and the Roundtable on Sustainable Biomaterials (RSB), an enterprise which aims to help small landowners enter the biofuels marketplace.

But Boeing does not follow in the path of some other multinational monopolies like Monsanto, which requires that farmers grow a single, genetically modified and licensed crop.

“What we are seeing is that, in some cases, there may be opportunities to develop new biofuel crops. That is, to add a crop to a farmer’s itinerary.  It’s not an either/or scenario, it’s an ‘and’.” Kowal notes, adding that Boeing and its partners are very much committed to the idea that this initiative has to be productive on many levels, including the environment, in countries where they roll it out.

The fact that the initiative relies on two resources that are considered worthless in most locations – salt water and desert soil – is a big plus. The addition of fish or shrimp, as in aquaculture, is clearly a value-added proposition. The fact that Boeing’s consortium is also looking at a newer and even more energy-efficient fuel conversion technique puts the initiative well over the top. That both the FERC (United States Federal Energy Regulatory Commission) and the UAE, or United Arab Emirates, are offering their leadership is, in Kowal’s words, “very exciting!”

“The aviation industry has been looking at biofuels for a long time, and there is a real desire to find an alternative to petroleum.”

Welcome to the real Holy Grail. And for those who cite the aviation industry as being highly pollutive, Kowal is quick to note that it accounts for only about two percent of transportation industry emissions according to a 2013 fact sheet from the IATA, or the International Air Transport Association.

It’s hard to imagine, but in the not-too-distant future major airlines may operate in a very real near-zero-emissions framework, without having to buy into carbon credits or ecosystem “fixes”.

Not that that’s a bad thing.