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Posts Tagged ‘the environment’

The Atlantic Wind Connection (AWC) will stretch from New Jersey to Virginia, moving power up and down the shoreline to the highest capacity markets along the coast. As envisioned, it would eventually link some 6,000 megawatts worth of offshore wind turbines into the land-based transmission system, supplementing traditional power infrastructure with enough power to serve some 1.9 million households. Even before wind farms are constructed, the AWC would ferry cheaper power from southern Virginia to expensive energy markets in New Jersey.

The cable itself will be copper lined with about 2 inches of insulation, and it will be big; each foot of cable will weigh about 30 pounds. To bury it in the seafloor a jet plow – a tool that shoots ocean water into the sea floor at high to pressures to blast a trench – will cut a path for the cable, which will eventually be covered over again with sediment.

There are already some undersea transmission lines running off the Atlantic Coast, but this is the first line that will collect power from generators along the way. This presents a particular technological challenge. The AWC will carry direct current rather than alternating current like the onshore grid. DC is more efficient at moving power over long distances, but DC works best for point-to-point transmission rather than lines that have many inputs and outputs along the way.

To make the AWC work efficiently, the system will employ a series of substations along the way that section it off into a series of direct journeys rather than long line with lots of entry and exit points. Like offshore oil platforms, these intermittent platforms will absorb the power from future wind farms and introduce it to the grid via four connection point in Virginia, Delaware, and southern and northern New Jersey, saving wind developments the trouble and expense of having to build their own connections to shore. That in turn should lower the cost of entry for offshore wind projects, hopefully spurring development along the coast and making way for a future where alternative energies make up a bigger share of America’s energy portfolio.

[Google, NYT]

An unmanned Global Hawk recon drone will join a team of aircraft--all equipped with advanced weather instrumentation--to observe the 2010 storm season closer than ever before

This weekend, NASA is launching a six-week mission to study the formation and intensification of hurricanes, hoping to inform forecast models and improve hurricane prediction abilities. The GRIP experiment (for Genesis and Rapid Intensification Processes) involves more than a dozen satellite-quality scientific instruments onboard a Global Hawk unmanned drone, a converted WB-57 cold-war bomber and a modified DC-8.

Ramesh Kakar, the weather focus area leader for NASA's science programs, says the goal is to improve understanding of the physical processes that generate hurricanes. He hopes forecasters will assimilate GRIP data into their prediction models, improving forecasts and providing earlier warning for communities in a burgeoning hurricane's path.

So he's hoping for some storms.

"Of course I do not want these to get to the land -- just allow them to be spinning and then just move on," he says. "But yes, I hope we do get enough cases, that Mother Nature allows us to see enough genesis cases so that we can say this was a successful mission." The mission is timed to take advantage of the peak hurricane season, which generally starts in mid-August.

Click to launch the photo gallery for a closer look at aircraft and instruments of the GRIP mission

Scientists are increasingly skilled at predicting a hurricane's path once it forms, but it's very difficult to tell whether a tropical disturbance will grow into a named storm and if so, how big it will get, says Bill Gray, a renowned hurricane forecaster at Colorado State University who is not involved in the GRIP mission.

"It's a problem of the physics. We don't have good enough observations," he says. "A hurricane is a very complex thing. It requires large-scale features to be of a certain characteristic, and to understand the small-scale -- how the clouds evolve, the wind and condensation, see how these all interact with each other -- it's a complex thing. It's not so easy to piece all this physics together."

That's the goal of GRIP, Kakar says. Instruments on the Global Hawk are designed to study hurricanes' innards, using a microwave radiometer and radiosondes that rival the equipment used on NASA's next-generation tropical weather satellites, one of which won't launch until 2013. It contains instruments to measure wind, both horizontally and vertically; temperature and water droplet distribution inside clouds; pressure and humidity; and lightning.

The WB-57 airplane includes a new instrument that will take high-resolution radar measurements of the wind profile, from the ground to the aircraft's height, around 60,000 feet. This will give scientists a good idea of the wind speed around the hurricane.

The information can be used to produce better models, according to Tim Miller, an atmospheric scientist at NASA's Marshall Space Flight Center and principal investigator for the Hurricane Imaging Radiometer instrument.

"Even though we're only measuring the ocean's surface, computer models can take that information and use it to help develop a three-dimensional structure of the hurricane," he says.

Gray says a detailed picture of how hurricanes form could help forecasters make better guesses, but every storm is different.

"They develop and intensify in different ways. Often you go measure one or two systems and think you understand it, but then you find next year, a system will form quite in a different way," he says. "The storms are so variable in their structure and how they intensify and so on, that it is very hard to generalize."

He and colleague Phil Klotzbach just updated their forecast for the remainder of the season, and they're calling for 10 named storms. Gray says the ocean's thermal heat capacity is high and sea-surface temperatures are increasing; what's more, a La Nina effect, bringing cold water to the eastern equatorial Pacific, has taken hold.

Gray rings a bell on the Colorado State campus every year around Aug. 20, to herald the active part of the hurricane season.

"Given all those factors, we'll eat a lot of crow and be very surprised if this is not a very active year," he says.

But Kakar says even if the Atlantic remains quiet, GRIP will be a success.

"We will be looking at cases where there is potential for tropical storm formation, and it may not form. But that's again a successful experiment, because the G of the GRIP is focused on what happens in the genesis -- why some disturbances become tropical storms and some do not," he says. So either way, we will learn."

Nuclear energy is looking like it will be a big part of a fossil-fuel-free future in the U.S. But the big question remains as big as ever: What's to be done with the waste it generates?

Nuclear reactors create high-level nuclear waste, composed of spent fuel rods loaded with the still-radioactive isotopes created when uranium-235 fissions. Some of those isotopes, like cesium-137 and strontium-90, have half-lives of 30 years or so -- but high-level waste also includes plutonium-239, which has a half-life of 24,000 years. Thanks to the fission process, fuel rods are actually more radioactive when they come out of the reactor than when they go in. But at the moment, using the spent rods as a source of fuel just isn't cost effective. And 24,000-year storage solutions are hard to come by, it turns out.

In our gallery, an overview of some of the options being considered today.

Additional reporting by John Bradley

As of today, Wednesday, June 9, the oil spewing from the Deepwater Horizon well could have powered 38,000 cars, 3,400 trucks and 1,800 ships for a full year, according to University of Delaware professor James J. Corbett.

Corbett, a marine policy professor, has a Web site that calculates the spilled oil's lost potential on a daily basis. He uses an estimate of 19,000 barrels a day, the most recent government guess. He says he created the site to put the spill in perspective that petroleum users can easily understand.

Meanwhile, Science Magazine estimates $1 million in oil is being spilled each day.

And that's saying nothing of the lingering economic effects.

[PhysOrg]

Michael Gratzel invented low-cost solar cells that can be turned into electricity-generating windows, mobile solar panels and other devices. He won the $960,000 (€800,000) Millennium Technology Prize, awarded every other year by Finland's Technology Academy.

The cells use nanocrystal films to produce power from sunlight, the BBC reports. The particles are so small that they don't scatter light, and can collect solar energy from all sides. The cells are fairly cheap to make -- they use dye squeezed from berries, for instance -- which the Finnish academy said could be a breakthrough for solar energy.

Gratzel, who was born in Germany and now directs the photonics and interfaces laboratory at Ecole Polytechnique de Lausanne, in Lausanne, Switzerland, told BBC that natural photosynthesis was his inspiration.

The cells have already been used in consumer products, including as battery-charging backpacks. Gratzel suggests making windows from them -- "You could think that the glass of all high-rises in New York would be electricity-generating panels," he said.

He said he would invest his winnings in further research.

Three shortlisted entries were all vying for the world's biggest technology prize. The others were Sir Richard Friend of the University of Cambridge, who invented the OLED, and Stephen Furber of Manchester University, the principal designer of the ARM 32-bit RISC microprocessor, which is used in gadgets from iPhones to Zunes. Friend and Furber each won $179,775 (€150,000).

[Millennium Technology Prize via BBC]

Perhaps most optimistic is U.S. Coast Guard Adm. Thad Allen, the federal government's top man on the job, who this morning told the L.A. Times that the efforts to reduce the well pressure to zero appeared to be working. The drilling mud being pumped into the riser by ships on the surface has apparently reduced the well pressure significantly, though the pressure is still persisting.

Another senior technician working the top kill said initial data coming back from the well has triggered a sense of general optimism among engineers on the scene, as it appears the drilling mud is indeed beginning to accrue within the well and slow the flow of oil and gas. Moreover, the well is holding together, allaying the chief concern that the damaged riser might rupture again under the pressure.

If engineers can get the pressure down to zero, they should be able to begin pumping cement into the hole, capping the well and stopping the leak.

Of course, even if the well is capped there's still the issue of the quarter million barrels of oil that have already leaked from the ocean floor. Or is it half a million? Experts trying to pinpoint just how much oil is loose in Gulf waters have been studying video of the gushing oil plumes in an attempt to revise BP's initial estimate of 5,000 barrels per day. Their analysis, released this morning, says we're likely looking at more like 12,000 to 19,000 barrels per day, which means that as of May 17 some 260,000 to 540,000 barrels of crude had flowed into the ocean. That means at minimum, this disaster surpassed the 1989 Exxon Valdez disaster a full ten days ago.

You can watch the live feed of the ongoing top kill via our prior coverage here.

[New York Times, Los Angeles Times, Wall Street Journal]

The battery consists of two large silos filled with crushed rock. Electricity generated by the turbine heats and pressurizes argon gas and feeds it into the first silo. The gravel is heated to more than 900 degrees as the hot, pressurized argon passes through, though by the time the argon leaves the chamber it has cooled to ambient temperature.

The argon is then fed into the second silo where it returns to normal atmospheric pressure, initiating a cooling effect that chills the gas and rock to -256 degrees. Thus, the electricity is stored as a temperature difference between the two chambers. If the wind ceases to blow, the process is reversed, feeding the cold gas back into silo number one, powering a generator as it makes the transition back to hot from cold.

The process isn't a perfect closed energy loop, but Isentropic claims a complete trip through the cycle retains up to 80 percent of the original electricity. Even better, gravel is cheap; the cost per kilowatt-hour falls somewhere between $10 and $55, depending on the costs of other materials. Isentropic also claims the batteries are highly durable; according to the company's founder, a 164-foot tall silo with an equal diameter would retain half its energy even if left untouched for three years.

All that sounds pretty good, but Isentropic has yet to fully prove out the idea. The vast temperature differences generated by the argon sound quite drastic, and the director of the UK Energy Research Centre points out, gravel isn't the ideal material to have inside of machine with moving parts. As such, Isentropic is designing a pilot plant that could store 16 megawatt-hours in two silos just 23 feet tall by 23 feet in diameter. That's enough to cover a pretty big neighborhood during a long, windless stretch. The company is also in talks with an unnamed utility to build a larger demonstration facility.

[Guardian, Isentropic]