I recently finished up a feature for the May issue of TR on the rare-earth supply crisis, in the process of which I learned in some detail about the dirty processes used to make green technologies like rare-earth permanent magnets for hybrid and electric car motors. With that in my mind, and continued problems at Japan's Fukushima Dai-1 in the news, stories on the unintended consequences of energy technologies have been catching my eye this week.

On Tuesday, the Japanese government raised the severity rating of the accident at Fukushima Dai-1 to level 7 on the International Atomic Energy Agency's scale, which puts it on par with Chernobyl. At IEEE Spectrum, Eliza Strickland takes a look at the numbers and explains why even though the severity level is the same as Chernobyl, this doesn't mean the situation is as dire. But it's not over. She writes:

When a reactor at the Chernobyl nuclear power plant exploded in 1986, it sprayed radioactive material high into the air. Then graphite in the reactor began to burn, which sent a plume of highly radioactive smoke into the atmosphere. The drifting smoke spread radioactive materials over a wide area, and more than 300 000 people were eventually evacuated and resettled in safer areas. In total, the Chernobyl accident released an estimated 14 million terabecquerels of radioactive material.

There are several competing estimates of the Fukushima Dai-1's total emissions to date--but it seems clear that the radiation release is much lower than Chernobyl's. According to Japan's Nuclear and Industrial Safety Agency (NISA), the plant has released a total of 370 000 terabecquerels of radioactive material to date, while Japan's Nuclear Safety Commission estimates the number at 630 000 terabecquerels.

Researchers at Cornell have turned over a piece of shale and found some bad news about natural gas, which burns cleaner than coal but, when its entire life cycle is taken into account, has some risks that some say have not been adequately addressed. In the New York Times, Tom Zeller reports on a Cornell study that says the chief component of natural gas, the greenhouse gas methane, leaks out of shale gas wells and pipelines at an alarming rate of 7.9 percent. Natural gas producers quoted in the story dispute the number, saying it would be bad business for them to let so much of their product go. TR will have a story looking at this issue sometime this week. From the Times story:

Mark D. Whitley, a senior vice president for engineering and technology with Range Resources, a gas drilling company with operations in several regions of the country, said the losses suggested by Mr. Howarth's study were simply too high.

"These are huge numbers," he said. "That the industry would let what amounts to trillions of cubic feet of gas get away from us doesn't make any sense. That's not the business that we're in."

And in good but vague news, the owner of the biggest rare-earth mine in the Western Hemisphere, Molycorp Minerals, announced late last week that it will be entering into a research agreement with the Ames National Laboratory in Iowa. The Ames Tribune has a short item. I sat in on the press conference and neither party would provide details about what rare-earth research problems they're tackling or how much money Molycorp will give Ames. But there are many problems to tackle, from coming up with more efficient ways to use the materials in magnets to cleaner processing methods. It seems likely, but I'm just speculating, that Molycorp would fund ongoing research at Ames on cleaner methods for purifying rare earth metals, the first step in making magnets and other products (making permanent rare earth magnets is in Molycorp's plans for the coming years). From previous interviews with Ames scientists, I've learned that the lab is developing a catalytic purification process that would eliminate the need to use fluoride, but previously had not had the money to get the process to pilot scale any time soon.

The U.S. Department of Energy (DOE) will release a report today pointing to the risk of disruption in the supply of materials critical to making hybrid-car batteries, energy-efficient lightbulbs, and lightweight wind turbines. China supplies 97 percent of these materials, a group of elements called rare-earth metals.

The report will be unveiled today at a conference at the Center for Strategic and International Studies in Washington, D.C. According to the New York Times, the Obama administration is expected to raise the issue with Chinese officials in trade talks today. China imposes export taxes on these materials, and this fall temporarily blocked their export to Japan, one of the biggest consumers, altogether. While research groups at Hitachi, GE, and academic labs work on alternative materials, mining companies outside of China are planning to ramp up production. But people in the mining industry are concerned about the repercussions of the movement, which occurred over a decade ago, of R&D, engineering expertise, and intellectual property out of the United States. The DOE report also points to these concerns about infrastructure, and indicates a political resolve to begin to remedy it.

Until the late 1990s, California's Mountain Pass mine was the world's major supplier of these materials, but a combination of environmental problems and the emergence of less expensive supplies from China pushed mining company Molycorp to halt production; the company let its mining permits expire in 2002. Still, the mine has remained the number two supplier of rare-earths outside of China, processing accumulated ore and selling about 3,000 tons this year. Reserves at Mountain Pass, California are the highest in the world outside of China.

Molycorp claims to have developed environmentally friendly processes and will restart active mining at a rate of 20,000 tons per year in 18 months, with the possibility to scale up to 40,000 tons under current permits. According to the company, 2010 U.S .demand is projected to be 20,000 tons. However, Molycorp will not sell all its product in the United States but will also focus on Japanese and European markets. The company last week announced a $130 million funding deal with Japanese company Sumitomo that promises the financier "substantial quantities of rare-earth products."

Lynas Corporation of Australia will begin active mining at the second largest reserve of rare earths outside of China, at Mt. Weld outside Perth, at the end of next year.

courtesy of ETH Zurich

Tiny "robots" that could perhaps someday help doctors examine organs, deliver drugs directly, or even perform microsurgery. But first researchers need to find reliable and accurate ways to control microscopic devices, which of course have little room for onboard power, sensors or propulsion.

Scientists have previously used methods including magnetic and electrostatic forces, and attaching live bacteria. In the latest issue of the International Journal of Robotics Research, researchers from ETH Zurich demonstrate particularly deft control of a microbot, dubbed MagMite.

MagMite, pictured above, is 300 micrometers by 300 micrometers (with a thickness of 70 micrometers). It consists of two magnetized components, connected by a tiny spring. In the presence of a magnetic field, the two pieces try to bend toward each other, storing that tension in the connecting spring. By turning the magnetic field on and off very quickly, the researchers can use the loaded spring to propel the microbot forward, and by changing the direction of the magnetic field the microbot will turn.

In the video below, MagMite wins the 2009 Nanogram RoboCup competition by autonomously pushing a tiny particle into a target while avoiding obstacles. Frutiger says the control method could also be useful in a lab setting for manipulating tiny biological matter. Currently, the MagMite only works in two dimensions.