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Written by Philip Proefrock on 11/12/11
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This article is part of a series on alternative possibilities in nuclear power.
Previously at EcoGeek: Alternative Possibilities in Nuclear Power
Pebble Bed Reactor
The pebble-bed reactor was supposed to be another intrinsically safe, and "melt-down proof" design. "Pebble bed reactors are helium-cooled, graphite-moderated reactors in which the fuel is in the form of tennis ball-sized spherical "pebbles" encased in a graphite moderator. New fuel pebbles are continuously added at the top of a cylindrical reactor vessel and travel slowly down the column by gravity, until they reach the bottom and are removed." Cooling uses an inert gas such as helium, rather than a liquid, which simplifies many of the reactor systems.
"The use of helium and graphite allows the reactor to burn the fuel efficiently and to operate at much higher temperatures than conventional light water reactors." Since the pebble bed reactor was already designed to operate at very high temperatures, and since its cooling medium was a gas, rather than a liquid, the control systems for a pebble bed reactor could be much simpler. The largest problems that need to be dealt with for a boiling water reactor - overheating and coolant boiling away - are not concerns for a pebble bed reactor. The pebble bed also produces less power as the temperature rises, so the design is effectively self-limiting.
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Here at EcoGeek we write about all the various and powerful ways in which our brains are saving our planet. Enjoy! |
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Written by Megan Treacy on 23/01/12
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Last week, Apple officially unveiled its iBooks 2 textbook platform where iPad users can download electronic versions of textbooks that are not only interactive, but cheaper too. Apparently, it was just what educators and students were waiting for because early reports are saying that in just its first three days the iBooks store saw 350,000 downloads of e-textbooks.
Apple has partnered with the three textbook publishers Pearson, McGraw Hill, and Houghton Mifflin Harcourt, who together represent 90 percent of the textbook market. The e-textbooks come equipped with features like 3D animated models, random pop-up quizzes and the ability to create sticky notes on pages and then have them assembled into digital 3 x 5 notecards for use as study aids.
The digital textbooks also come with the advantage of being updated whenever new information comes along, keeping owners from having to purchase subsequent editions. Even with these added elements, high school e-textbooks cost $14.99 or less.
Studies have shown that once a certain threshold of e-books are downloaded, replacing the purchase of hard copy books, the carbon footprint of the e-reader or tablet itself is canceled out and from that point forward users are making a positive environmental impact.
With the size and weight of textbooks, that threshold could be even lower than with a typical book. Between the Amazon's Kindle textbook store and the new Apple textbook store, students now can save their backs, their wallets and help the environment: win-win-win.
via Engadget
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Written by Megan Treacy on 22/12/11
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The City of Austin, Texas may enact one of the toughest bag bans in the country come 2016. The city council is set to vote on the ban next month that would require retailers to only offer reusable bags.
The ban would include a three-year adjustment period starting in 2013 for retailers and consumers to get prepared where single-use bags could still be purchased at 25 cents each. Once 2016 hits though, only reusable bags would be allowed and that would include City of Austin facilities and all city events.
Some single-use bags would be exempt from the ban, including: restaurant carryout bags, bags for wine and beer, dry cleaning bags, newspaper delivery bags and bags that hold meat, fish, produce, bulk foods or pharmaceuticals.
Reusable bags would be defined as bags that are made of fabric or durable materials or thick paper or plastic with some recycled content. The city would pay for an aggressive marketing campaign to get the word out about the ban with proceeds from the 25 cent fee.
via Austin Statesman
Image via mtsofan
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Here at EcoGeek we write about all the various and powerful ways in which our brains are saving our planet. Enjoy! |
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Written by Philip Proefrock on 26/03/12
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I have a new smart meter on my house, and I'm far from the only one. The number of smart meters installed across the country is growing quickly. Smart meters are digital, rather than analog, equipment to measure the amount of electricity each customer uses. However, smart meters are able to collect more data than just the electricity that has been used, they can also track the amount of electricity used as well as when it was used. Smart meters also are often equipped with wireless two-way communication for easier meter reading, among other uses.
The White House recently announced an agreement with nine "major electricity suppliers" under which consumers will be able to get access to data about their own energy use. In addition to getting the information themselves, this would allow consumers to use third-party applications to track their energy use and "empower consumers to make wiser energy decisions." Congressional representative Ed Markey plans to introduce legislation that would require this information to be available to all consumers.
image: EcoGeek
via: Rep. Markey Press Release
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