Flying on Vegetables

By Matthew L. Wald

Crude oil from algae manufactured by Sapphire Energy for Continental Airlines. Converting the airline industry to biofuels may be easier than converting the car market.

The scheduled flight on Wednesday of a Continental Airlines 737 fueled in part by biofuels made from jatropha and algae was experimental (see my report on the state of biofuels in the airline industry from Wednesday’s paper here). But if the fuel can be certified by international standards agencies, it could become as common as, say, ethanol added to gasoline.

It might be even more so, because the goal is a “drop-in” substitute that can be used at any percentage, in any jet or any airport fueling system.

In theory, people in the industry say, replacing petroleum in airplanes could be easier than replacing it in cars, even though jet fuel has to meet specifications that are of little concern on the highway, like weight (hauling fuel is a major use of fuel, after all), or how well it flows at 40 degrees below zero, which is a temperature big planes face for hours as they cruise in the stratosphere.

Because fuel quality has such importance to safety, some energy experts thought aviation would be the last to switch. “For 40 years we had the philosophy we’d be the ones using the last drop of oil,’’ said Carl E. Burleson, director of the Federal Aviation Administration’s Office of Environment and Energy.

But compared to the market for gasoline or diesel, the market for jet fuel is simpler, industry experts say.

The number of fueling stations and customers are both much smaller than for motor vehicle fuel, making marketing easier. The number of engine manufacturers is smaller, too, so there are fewer parties to convince when switching to something new. And unlike the specifications for gasoline, which vary from state to state and country to country, there is a single standard for jet fuel, regardless of where it is sold.

As with substitute motor fuels, though, substitute jet fuel has mixed environmental implications. European carriers have tested fuel made from palm oil, but recent studies have persuaded some environmentalists that clearing tropical jungle to make space for palm plantations is a mistake, releasing more greenhouse gases than the new fuel will save. And the only petroleum substitute in common use now is made from coal, a switch that can save money and petroleum but makes greenhouse gas problems worse.

The precise carbon effect of using algae, jatropha or other substitutes will be studied closely and probably litigated, because airlines say they want to use such fuels to meet European regulations taking effect in the next few years, which will force them to cut carbon output or buy carbon allowances.

[Via greeninc.blogs.nytimes.com]

Fuel from Vinegar? Zeachem Gets $34 Million to Try it Out

The start-up says it can turn an acre of poplars into 2,000 gallons of fuel that bears some resemblance to salad dressing.

Zeachem, a cellulosic ethanol company that says it can get more fuel out of plant matter than its competitors, has just raised $34 million in a second round of funding to see if its formula will work on a grand scale.

Investors in the second round included Mohr Davidow Ventures and Firelake Capital but also Valero, the large oil refiner, and PrairieGold Venture Partners, a VC firm that specializes in alternative fuel. Valero also recently invested in algae fuel start-up Solix.

"We're seeing a migration with the chemical and refining guys. They see that it (cellulosic ethanol) is going to be part of the energy solution," said Jim Imbler, Zeachem's CEO. "For people working on thin margins on a lot of barrels, it makes a lot of sense."

The company, which was founded by execs from the petrochemical industry and biologists from Coors, takes a somewhat novel approach to turning cellulosic plant matter into liquid fuel that combines both thermochemical and biological techniques.

The process, Imbler says, realistically could let Zeachem get 135 gallons of fuel for every bone dry ton (BDT) of plant matter. Theoretically, you could get to 160 gallons, but the additional expense would eviscerate the gains.

Competing processes, such as turning plant matter into synthetic gases, or having genetically enhanced bacteria do the job focused on one approach or the other only yields 90 to 115 gallons. High capital costs and delays have already put the cellulosic ethanol industry behind schedule. Congressional mandates to get 100 gallons into circulation in the U.S. next year will likely be missed. Instead, only around 28.5 million gallons will get pumped out.

So far, Zeachem has only demonstrated that it can produce fuel at those levels in lab bench tests and computerized simulations. It will next build a 1.5 million gallon-a-year facility to unwind unforeseen kinks and operational issues that crop up in actual production. That should be complete by the middle of next year.

If all goes well, a 25 to 50 million gallon-a-year facility will follow. Zeachem, by the way, isn't the only ethanol maker taking a combination approach. Coskata, which is working with GM, also mixes biology and industrial chemistry.

How does it work? After separating plant matter into cellulose, hemicellulose, and lignin, Zeachem employs a microbe to convert cellulose and hemicellulose--which can account for 61 percent of the material in wood--into acetic acid, the signature ingredient of vinegar, rather than alcohol. The conversion into acetic acid does not give off carbon dioxide, leaving more carbon in the fuel.

Meanwhile, the company cooks the lignin to extract hydrogen. The hydrogen is subsequently combined with the acetic acid to produce ethanol. Two-thirds of the energy in the ethanol comes from the acetic acid, while one-third comes from the added hydrogen, said Imbler, which is similar to the ratio of initial molecules from the wood. In a sense, the company is blowing apart wood and reforming it as an alcohol.

"And we have no new bugs and no new equipment," he said. In other words, genetically modified plants aren't needed and the company uses conventional chemical processing equipment.

The company's process is optimized for making fuel out of hybrid poplars, but Zeachem continues to experiment with eucalyptus and other plants. Although hybrid poplars might prove to be the best trees for fuel, expect to see a variety in the future. Tree companies and ethanol refiners don't want to become dependent on a monoculture that could be wiped out or seriously damaged by an unknown pest.

"The forest of the future is going to be more of a mosaic," he said.

Expect to see fairly substantial improvements in forest yields as well. To date, tree producers have bred trees to produce wood for structures or furniture, i.e. hard, durable wood. That's the opposite in some ways of what you want for ethanol. Tree producers have only just begun to think of liquid fuel as a primary market. The breeding for these qualities thus is just beginning. Some early breeders are already reporting 20 BDT per acre. Many of these types of trees could be grown on marginal land.

Even if you knock it down to 15 BDT, the company could possibly support a 100 million gallon a year plant with 50,000 acres.

Zeachem will likely not aim at the general transportation market. Like some other ethanol providers, it will aim at big customers with trucking and transportation depots that buy fuel directly.

[Via www.greentechmedia.com]

Ocean Energy from Warm Water and Wind

Ocean energy has received a lot of space recently, and from the comments posted online and in e-mails I've received, it's reassuring to find that people are reading the columns, and to discover their interest and concerns. It's time to move on to other ocean issues, but there are two other sources of ocean-related energy that I want to cover.

One is Ocean Thermal Energy Conversion OTEC, a concept that has been around for more than a century but never successfully developed on a commercial scale. It sounds a lot like OPEC, but is clearly worlds apart. The oceans cover 71 percent of the Earth's surface and are heated daily by the sun, so there is a vast amount of solar energy stored in warm surface waters. The challenge is how to extract it economically. OTEC generates electricity by taking advantage of the temperature difference between the warm surface water and cold water at depth. As in any heat engine, the greatest efficiency is obtained when the temperature differences are the greatest. Differences of at least 20 degrees Celsius 36 degrees Fahrenheit are common in tropical latitudes such as Hawaii. However, the relatively small temperature difference means that large flows of both warm and cold water are required.

In a closed OTEC cycle, the warm surface water runs through a heat exchanger to vaporize the working fluid, and the vapor runs through a turbine to generate electricity. The required cold water is brought from the depths up to the surface through the cold-water pipe, and it condenses the working fluid back to liquid. A practical cold-water pipe is one of the two key technologies required to commercialize OTEC, and is a huge component, being about 33 feet in diameter and twice as tall as the Empire State Building.

Lockheed Martin is using modern fiberglass and low-cost composite material manufacturing methods to develop a cost-effective, reliable cold-water pipe. Workers at their nearby Palo Alto/Sunnyvale location recently completed an initial small-scale "proof-of-principle" demonstration of the new fabrication process, and the company recently received a $1.2 million grant from the U.S. Department of Energy to demonstrate it at large scale. OTEC could enable Hawaii to achieve energy independence, ending its almost total reliance on expensive imported oil.

Wind power has been growing at a pace comparable to solar power with the worldwide capacity increasing at 32 percent per year, on average, for the past decade. Generation costs have fallen by 50 percent over the past 15 years and modern wind turbines have improved dramatically in their efficiency and reliability. More than 70 countries around the world are now using wind power, with the U.S. in the lead with 21,000 megawatts of existing capacity enough to power nearly 17 million homes, and an additional 8,600 megawatts under construction. California is second behind Texas in wind energy development with 2,500 megawatts of existing capacity. The growth of new wind farms has been spurred by a modest tax credit, but one that Congress has repeatedly threatened to eliminate, which has slowed investment.

While we usually think of wind turbines on hillsides such as Altamont Pass on the way to Stockton, wind farms can also be sited offshore. Depending upon water depths, different foundation systems are required, including floating platforms at greater depths. One of the largest offshore areas in the U.S. with shallow water is off Cape Cod, where a major wind farm proposal 12 miles offshore is moving forward, despite some local opposition. While local concerns about how wind turbines might affect offshore views may have some merit, they must be balanced against the social costs of other forms of electrical power generation.

Wind turbines can also be built farther offshore in deeper water, although foundation costs increase with greater water depth, and costs of connecting with existing power grids increase with distance offshore. Still, there are advantages to siting wind farms further offshore. Wind speeds tend to be higher and the wind is steadier, which means more energy is available.

A recent study of the offshore wind energy potential along California's coast using existing technologies indicates we have the potential to provide 26-112 percent of the state's total electrical needs, depending upon the height of the wind turbines and wind velocities utilized. This may be our best near-term, renewable ocean energy opportunity.

Gary Griggs is director of the Institute of Marine Sciences and Long Marine Laboratory at UC Santa Cruz. He can be reached at griggs@ucsc.edu.

[Via www.mercurynews.com and Alternative Energy blog]