Thursday, July 22, 2010

Hawai'i's pond scum biofuel potential

Green water in a swimming pool is a sign of trouble.

But in many applications, pools of algae-rich water represent another kind of green: major financial investment, and significant financial reward. Often skewed more to the cost than the profit side.

Hawai'i is a hotbed of algae research, and much of that work is aimed at squeezing valuable biofuel out of the waterborne plants. But we're still some distance from being able to full your car, or your electric generating plant, with algae-based biofuel.

“Many years of both basic and applied science and engineering will likely be needed to achieve affordable, scalable, and sustainable algal-based fuels,” says a new U.S. Department of Energy report reviewing the status of a lot of the research. It's the National Algal Biofuels Technology roadmap.

Still, whodathunk pond scum would generate so much interest?

The report repeatedly cites Hawai'i as one of the places with lots of potential for this use.

First there's sunlight: “A significant portion of the United States is suitable for algae production from the standpoint of having adequate solar radiation (with parts of Hawaii, California, Arizona, New Mexico, Texas, and Florida being most promising).”

Then water: “Areas with higher annual average precipitation (more than 40 inches), represented by specific regions of Hawaii, the Northwest, and the Southeast, are desirable for algae production from the standpoint of long-term availability and sustainability of water supply.”

Although, of course, these can work against each other. Hawai'i is also cited as a place with high evaporation rates.

We are credited with a long growing season, and our water tends not to spend a significant part of the year in its solid form.

So, the Islands can readily grow this stuff. Why would we want to? Well, in the post-petroleum energy picture, there are all kinds of players, but there is still a strong role for liquid fuels. Oil is a stunningly dense form of energy storage, appropriate for things like running aircraft. Nobody's yet figured out how to stuff enough batteries into a 767 to power it across an ocean.

What's cool about algae as a source of oil? The study says: “1) high per-acre productivity, 2) non-food based feedstock resources, 3) use of otherwise non-productive, non-arable land, 4) utilization of a wide variety of water sources (fresh, brackish, saline, marine, produced, and wastewater), 5) production of both biofuels and valuable co-products, and 6) potential recycling of CO2 and other nutrient waste streams.”

The latter is why Hawai'i BioEnergy put its test facility next to a power plant on Kaua'i. It could use the carbon dioxide from the power plant exhaust as food for the algae. See Hawaii BioEnergy here.

That's just one of several algae biofuel experiments in the state, and they're represented on all the major islands.

There's HR BioPetroleum, a partner of Royal Dutch Shell, through their joint venture Cellana on the Big Island. And here.

Meanwhile, HR Biopetroleum has signed an agreement for a Maui algae biofuel facility with partners Alexander & Baldwin, Hawaiian Electric and Maui Electric.

And there's Phycal on O'ahu. More on why Phycal picked Hawaii here.

It's still all experimental. As the Department of Energy report says, “a scalable, sustainable and commercially viable system has yet to emerge.”

© Jan TenBruggencate 2010

Sunday, July 18, 2010

Atlantic/Pacific circulation drivers swapped 16 millennia ago

One way of looking at the global ocean current picture is that it's driven by gravity.

(Image: Left panel ‐ glacial current conveyor belt flow 21,000 years ago; Right panel ‐ reorganized conveyor belt flow 17,500‐15,000 years ago with deep‐water sinking in the North Pacific. Credit: IPRC.)

Cold water is heavier than warm water, so gravity lets it sink. Saltier water is heavier than less salty water, so gravity also forces it to sink.

Warm water flows northward in the Atlantic, gets chilled, and sinks. It sucks other water behind it, and pushes on the water in front of it, launching a system of currents that ultimately extends around the world.

Hawai'i scientist Axel Timmermann, of the University of Hawai'i's International Pacific Research Center (IPRC), is part of an international team of scientists who have studied what happened when this system stopped working 16 millennia ago. It was a period of dramatic climate change that scientists call the Mystery Interval.

They reported their findings in the July 9 issue of Science. A press release here.

A research team looked at sediment cores from 30 places around the Pacific, and studied the marine organisms that lived in the Pacific during the period in question.

They write that as the last ice age ended, between 17,500 and 15,000 years ago, melting glaciers dumped so much cold fresh water into the North Atlantic that it blocked the big current flow there.

But the world's ocean currents didn't stop. Instead, the North Pacific took over as the prime mover in current flow, said Timmermann's co-researcher and lead author in the Science paper, Yusuke Okazaki, of the Japan Agency for Marine-Earth Science and Technology:

“Around 17,000 years ago, the North Pacific surface waters grew saltier, and the resulting higher density there caused massive sinking. Newly formed icy deep water spilled out of the subarctic North Pacific at depths of 2000-3000 meters merging into a southward flowing deep western boundary current. A warm, strong poleward current, moreover, formed at the surface. It released much heat into the atmosphere and supplied water for the Pacific deep overturning circulation,” Okazaki said.

Timmermann said that the collapse of the North Atlantic current system might have launched a severe cooling episode, but that the new North Pacific current activity began moving water in such a way that equatorial heat was transferred northward, “and possibly prevented further cooling of the Northern Hemisphere.”

The new Pacific activity may also have roiled up deep-ocean waters rich in carbon, and increased the globe's carbon dioxide levels, causing still more warming, the authors say. The result may have been that instead of the dying Atlantic circulation causing more cooling, the new Pacific circulation may have had the opposite effect, said IPRC's Laurie Menviel, another author of the paper.

“This could have catalyzed further warming and accelerated the glacial meltdown,” Menviel said.

It's an intriguing theory. Timmermann said more tests are needed to confirm the conclusions about activity during the Mystery Interval.

“Our findings caution against the Atlantic-centric view of abrupt climate change that has prevailed amongst climate scientists for the last 20 years. They highlight the complicated adjustments happening in the global ocean during these periods of climate change, in which the North Pacific was definitely a player to be considered.”

Timmermann also said that it is unlikely a similar Atlantic-Pacific swap could occur today, mainly because the Bering Strait between North America and Russia-Siberia was once iced over and now is open. That means water movement would prevent a dramatic salinity change that launched the North Pacific circulation system more than 15,000 years ago.

If this stuff fascinates you, there's a three-part National Science Foundation video interview with Timmermann here.

The paper: Okazaki, Y., A. Timmermann, L. Menviel, N. Harada, A. Abe-Ouchi, M. O. Chikamoto, A. Mouchet, H. Asahi, 2010: Deep Water Formation in the North Pacific During the Last Glacial Termination, Science, July 9, 2010.

© Jan TenBruggencate 2010

Wednesday, July 7, 2010

Time machine reveals Hawaiian prehistory: book

Any archaeological dig by definition takes you back in time, and the years-long studies at the Makauwahi cave and sinkhole at Maha'ulepu on Kaua'i chronicles a few thousand years of history.

David Burney calls the site a “poor man's time machine,” and does a remarkable job supporting that definition in his new book, Back to the Future in the Caves of Kaua'i.

I was struck by his opening lines: “Visitors come to Hawaii seeking paradise, but the truth is, these islands have become a kind of living hell for nature.”

Makauwahi, whose lost name was recovered as part of the investigation, chronicles the descent from a pre-human Hawaiian environment filled with unique forms of wildlife, and surrounded by a dense, diverse native dryland forest.

The initial blow came from the first invasion by humans and the rats they brought with them. Land use practices, and the use of fire helped bring about the initial decline. The arrival of Westerners speeded it up.

Burney did the work with a team of fellow scientists and volunteers, key among them the late archaeologist Bill Kikuchi and Burney's wife, Lida Pigott Burney. He calls his work paleoecology, the study of ancient environmentals through the use of fossil organisms, and Burney adds an overlay of archaeology to study human impacts on the natural environment.

Makauwahi is a stunning natural feature. A limestone shelf, formed by ancient sand dunes hardened into rock, eaten away from within by flowing water, forming deep cave systems. The roof of the largest cave portion has collapsed, creating a wide skylight, with dark caves extending from within it.

Burney found that it was possible to dig down through the wet sediment on the Makauwahi floor and turn the time machine's dial to points in the past.

The surface inches included plastics and beer poptops. A few feet through the Western period, iron fish hooks and goat bones were found. A few more feet through the early Hawaiian period, were canoe parts, shell fishhooks and a basalt mirrror. And then deep into the pre-human past, the bones of strange extinct birds and shells, and the pollen of long-lost forest plants were located.

He found old structure posts inside the cave, indicating its use in early human times, and he tracked down families with their own histories about the use of the cave. He found ancient traditions about the cave. He tracked the debris from a tsunami that helped fill the cave floor, and the silt from surrounding fields that flowed in during floods.

With a remarkable tally from seed and pollen studies of the plants that once existed around here, Burney and Lida Burney launched an ecorestoration effort, planting some of the species that their work proved had once thrived around here.

It's not a perfect restoration. Some of the plants are extinct. In other cases, the exact species can't be determined, so Burney and his team went to similar habitats to identify the most likely near relatives.

That's how the Ni'ihau fan palm, Pritchardia aylmer-robinsonii, came to be planted inside the cave, where it thrives. It might be the same Pritchardia species whose pollen was found in ancient sediments, or not quite. But it's likely close.

The ecological restoration effort is a step—rebuilding the past as opposed to discovering the past--another way of rolling back the clock.

In his summation, Burney recalls his book's opening lines about the environment's destruction by humans: “Wouldn't it be a big relief if we could discover, over the next few critical years, that humans can, in a similar stretch of a few generations, actually stop wiping out the rest of nature while maintaining or even improving the human standard of living.”

The book weaves a number of stories, about the history of the region, about a scientist's inquiries, about a family, and friends, and about how we are changing our planet. It's a good read. Pick it up at your local bookstore, or try the National Tropical Botanical Garden bookstore or other online resources.

Back to the Future in the Caves of Kaua'i: A Scientist's Adventures in the Dark, by David A. Burney, Yale University Press, New Haven & London, 2010, 198 pages, hardcover, $28.

© Jan TenBruggencate 2010

Saturday, July 3, 2010

Hyper efficient cars near the X Prize finish line; liquid fuel/electricar battle revisited

It turns out that building a four-seater car that can get 100 miles to the gallon isn't easy.

Even if you offer a $10 million prize to do it.

(Image: the Edison2 car, a four-seater with a single-cylinder turbocharged engine. Credit: Edison2.)

With all the interest in bringing electric cars to Hawai'i from folks like Korean carmaker CT&T, and Project Better Place, it's interesting to look at the future of high fuel-efficiency vehicles. It turns out a lot of them are electric--but it also turns out there's a new view on powerplants.

The Progressive Insurance Automotive X Prize offered $10 million to build a car that could go 100 miles on a gallon, and it got lots and lots of interest. Dozens of companies, colleges, backyard shops, high school shop classes and innovative entrepreneurs hopped up to say they could do it.

Ultimately, 26 vehicles were accepted into the testing, which is conducted by Consumer Reports. The testing includes such requirements as that the car be able to run the required distance and that it's stable enough to be safe for the highway (for example, it doesn't flip over on a sharp turn).

There are also emissions tests, fuel economy tests, and ultimately, the requirement that the car be able to run for hours, getting the required 100 miles to the gallon (or in the case of vehicles run on electricity, fuel cells or other non-gas engines the equivalent.)

But after two rounds of testing, there's only one team—which has two vehicles—still in the running for the Mainstream class prize for a traditional four-seat, four-wheeled car that mainstream consumers might buy.

Another 13 vehicles are still alive in the Alternative class, which includes all kinds of interesting cars with two or three wheels, generally seating two people instead of four. Here is the rundown on the standings so far.

The final phase of testing will take place during the last two weeks of July at the Michigan International Speedway, and the X Prize is to be issued in September.

Cars don't need to be gasoline fueled. They can be run on alternative fuels, and even electricity. Indeed, a lot of the alternative cars are electric cars.

The remaining competitor in the Mainstream class is a team called Edison 2, which has two versions of its “Very Light Car,” which are both powered by internal combustion engines.

The cars run a single-cyclinder, turbocharged 40-horsepower power plant. It uses E85, which is 85 percent ethanol and 15 percent gasoline. And as the photo above shows, it's not your grandmother's Oldsmobile.

The Edison2 team is largely made up of sports car racers. Their cars seat four, have room for your luggage, and advertise a top speed of 100 miles an hour. They have a 6.5-gallon fuel tank, and before you worry that this is just too small, Edison2 says the cars have a range of 600 miles.

The key, according to the Edison2 website, is weight and wind resistance. So they worked very hard to build an aerodynamically efficient shape, and to cut weight wherever possible. For example, they used carbon-fiber instead of metal in some places, and managed to cut the weight of brakes from a pound to a few ounces.

They also claim the car is more recyclable than most.

The remaining cars in the competition are broken into two alternative classes, one for vehicles with side-by-side seating and one with tandem seating—one in front of the other. Edison2 also has a car in this group. Here's the list from the X Prize folks, listed by team name, car name, where they're from and how their car is powered.

Alternative Class - Tandem
Commuter Cars, Tango (Spokane, WA) Battery Electric
Edison2, Very Light Car #95 (Charlottesville, VA) Internal Combustion Engine
Spira, Spira4u (Carrollton, IL/Banglamung, Thailand) Combustion Engine
X-Tracer, E-Tracer 7002 (Switzerland) Battery Electric
X-Tracer, E-Tracer 7009 (Switzerland) Battery Electric

Alternative Class - Side-by-Side
Amp, amp'd Sky(Cincinnati, OH) Battery Electric
Aptera, Aptera 2e (San Diego, CA) Battery Electric
Li-ion Motors, Wave II (North Carolina) Battery Electric
RaceAbout Association, RaceAbout (Finland) Battery Electric
Tata Motors, Indica Vista EV X (Coventry, UK) Battery Electric
TW4XP, TW4XP (Italy) Battery Electric
Western Washington University, Viking 45 (Bellingham, WA) Gas/Electric Hybrid
ZAP, Alias (Santa Rosa, CA) Battery Electric

One of the odd features of the competition is that most of the cars are electric, but the only competitor still standing in the Mainstream class uses a liquid fueled engine. From the Edison2 website, here's their explantation for that.

“Edison2 entered the X Prize accepting the conventional wisdom that success would require an electric or hybrid electric drive. In fact, this assumption underlies our name, Edison2.

“Examination of the interplay between weight, drag, regenerative braking and acceleration, however, demonstrated to us the key importance of low weight and low aerodynamic drag in automobile efficiency, and led us away from a hybrid or electric drivetrain.”

Indeed, the competitor says, the heavy batteries required in an electric car work against the vehicle's fuel economy. The company blog says six pounds of gas has the energy contained in 500 pounds of battery.

Many teams think outside the box to reach the electric car conclusion. Interestingly, this team thought outside that box, and got back into the original box.

© Jan TenBruggencate 2010