Category: Mobility

How to rescue biofuels from a sustainable dead end

In 2011, I scrutinized a gathering wave of biofuels for Nature, and that deep dive on making fuels from woody rather than sugary plant material remains one of my most-cited works. Perhaps because we nailed what emerged as the technology’s as-yet-insurmountable hurdle: making the conversion processes work consistently at industrial scale.

A little over a decade later Nature take another look at the sustainability of biofuels. The picture isn’t pretty, thanks in part to the failure of those cellulosic fuels.

Biofuels continue to grow in ways that overlap with food crops, contributing to agricultural expansion at the expense of carbon-storing forests and grasslands. And poorly conceived and regulated mechanisms for tracking and rewarding carbon storage by farms threaten to exacerbate the trouble.

It will take a “ground-up revamp” for agriculture to get biofuels right, both for the environment and for farm communities. As we conclude, it looks like déja vu all over again: “If the sustainability of biofuels depends on such fundamental changes, one has to wonder whether another next-generation biofuels failure isn’t the more likely outcome.”

Read the full story @Nature, or in Scientific American.

by pfairley

Scientific American: Solar And Wind Power Could Ignite A Hydrogen Energy Comeback

Hydrogen is flowing in pipes under the streets in Cappelle-la-Grande, helping to energize 100 homes in this northern France village. On a short side road adjacent to the town center, a new electrolyzer machine inside a small metal shed zaps water with electricity from wind and solar farms to create “renewable” hydrogen that is fed into the natural gas stream already flowing in the pipes. By displacing some of that fossil fuel, the hydrogen trims carbon emissions from the community’s furnaces, hot-water heaters and stove tops by up to 7 percent.

So begins my February 2020 feature article for Scientific American which explains why hydrogen energy — presumed dead after a round of hype and disillusion two decades ago — is roaring back. Renewable hydrogen is central to the European Commission’s vision for achieving net-zero carbon emissions by 2050, for example, and a growing focus for the continent’s industrial giants. As of next year, all new turbines for power plants made in the European Union are supposed to ship ready to burn a hydrogen–natural gas blend, and the E.U.’s manufacturers claim the turbines will be certified for 100 percent hydrogen by 2030.

This time around it is the push to decarbonize the electric grid and heavy industry—rather than hope for fuel cell vehicles—that is driving interest in hydrogen. “Everyone in the energy-modeling community is thinking very seriously about deep decarbonization,” says Tom Brown, who leads an energy-system modeling group at Germany’s Karlsruhe Institute of Technology. Cities, states and nations are charting paths to reach nearly net-zero carbon emissions by 2050 or sooner, in large part by adopting low-carbon wind and solar electricity. Integrated energy models show that they’ll have a hard time keeping the lights on during periods of low wind and sunlight without hydrogen, and that hydrogen will pay for itself long before it solves that problem.

by pfairley

Power Vampires Possess Smart Cars

By driving smarter, autonomous cars have the potential to move people in and around cities with far greater efficiency. Their projected energy performance, however, has largely ignored their energy inputs, such as the electricity consumed by brawny on-board computers. First-of-a-kind modeling shows that autonomy’s energy pricetag could be high enough to turn some into net energy losers.

Continue reading “Power Vampires Possess Smart Cars”

by pfairley

The Self-Driving Car’s Bicycle Problem

Robotic cars are great at tracking other cars, and they’re getting better at noticing pedestrians, squirrels, and birds. The main challenge, though, is posed by the lightest, quietest, swerviest vehicles on the road. “Bicycles are probably the most difficult detection problem that autonomous vehicle systems face,” says UC Berkeley research engineer Steven Shladover. Nuno Vasconcelos, a visual computing expert at the University of California, San Diego, says bikes pose a complex detection problem because they are relatively small, fast and heterogenous. “A car is basically a big block of stuff. A bicycle has much less mass and also there can be more variation in appearance — there are more shapes and colors and people hang stuff on them.” Bikes are also being left behind by the machine learning techniques that enable detection systems to train themselves by studying thousands of images in which known objects are labeled. Most of the training, to date, has employed images featuring cars, with far fewer bikes. Continue reading “The Self-Driving Car’s Bicycle Problem”

by pfairley

Chinese Bullet Trains’ Worrisome “Black-box” Controls

In August we brought you disquieting news that Hollysys Automation — the supplier of a control system implicated in China’s deadly bullet-train collision this summer — also provides controls for China’s nuclear reactors (which are multiplying just as fast as its high speed rail lines). The Hollysys story now looks darker after informed speculation reported in the Wall Street Journal that the company may not fully comprehend how the control systems work. Continue reading “Chinese Bullet Trains’ Worrisome “Black-box” Controls”

by pfairley

Nuclear Safety Implications in China’s Bullet Train Wreck?

The hand-wringing over China’s high-speed train wreck last month may have just begun if the government’s current explanation for the crash proves out. At present official fingers are pointing to a failure in the trains’ signaling system. The firm that installed them, it now appears, provides similar equipment for the nuclear reactors that China is building just as fast as it is adding rail lines. Continue reading “Nuclear Safety Implications in China’s Bullet Train Wreck?”

by pfairley

Compressed-air Car Proponents Losing Faith

Licensees of the much-hyped AirPOD minicar are pressing for results from Motor Development International, the Luxembourg-registered firm behind the compressed-air-powered vehicle. In recent postings to their websites and coverage by European news sources, some of MDI’s partners are now openly questioning the technology and MDI’s capacity to develop it — questions that Spectrum raised in November 2009 in the investigative feature, “Deflating the Air Car.”

When Spectrum’s feature went to print, MDI was guaranteeing mass-production of AirPODs within a few months at its development base on France’s Cote d’Azur. A year and a half later there is no sign of the promised minicars and their advertised 140-kilometer range, and outspoken licensees are blaming MDI. Continue reading “Compressed-air Car Proponents Losing Faith”

by pfairley