tag:blogger.com,1999:blog-28509288803371972322024-03-05T05:32:38.075-05:00EnviroBuzzWhat's happening in the environment, environmental science, and clean tech.Arun Sinhahttp://www.blogger.com/profile/16448414776484904929noreply@blogger.comBlogger166125tag:blogger.com,1999:blog-2850928880337197232.post-66039563194925146092010-07-11T17:45:00.006-04:002010-07-11T20:14:31.615-04:00Why Oil Will Be With Us for a Long Time<a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhLpoLepsVf9RavZzBPXj8Ls3dWxOF9s2v9eZ-nBqsiSurfQHSB8NVdVi59bXssH7IUXAqEY5fC9LilqeX0-XjBILvIQnc4t73z08NJxpjjSL3p4oSzzmxrO9YSiXU99-EHEznCx6Viqjmt/s1600/oil_lamp.jpg"><img style="float: right; margin: 0pt 0pt 10px 10px; cursor: pointer; width: 179px; height: 193px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhLpoLepsVf9RavZzBPXj8Ls3dWxOF9s2v9eZ-nBqsiSurfQHSB8NVdVi59bXssH7IUXAqEY5fC9LilqeX0-XjBILvIQnc4t73z08NJxpjjSL3p4oSzzmxrO9YSiXU99-EHEznCx6Viqjmt/s320/oil_lamp.jpg" alt="" id="BLOGGER_PHOTO_ID_5492806266145138706" border="0" /></a>In a remote village beyond an unnamed hill, where the last road ended miles ago, a man picks up an earthenware bowl. He pours some refined oil into it – maybe vegetable oil, maybe palm oil. Into the oil he inserts a cotton wick, then puts a match to the wick.<br /><br />That lamp will shine all night long.<br /><br />That villager could never have gotten the same result with solar or wind – not yet, anyway. Until we find a source of energy that combines the convenience, cost and potency of oil, we'll never give up on the black gold.<br /><br />Yes, I understand oil has its drawbacks. But society has decided that oil's pros outweigh its cons. The scales will continue to tip that way for quite some time.Arun Sinhahttp://www.blogger.com/profile/16448414776484904929noreply@blogger.com1tag:blogger.com,1999:blog-2850928880337197232.post-26147049317318712502010-06-26T18:48:00.011-04:002010-06-26T20:01:16.389-04:00Using Solar and Nuclear Energy Won't Cut Our Oil Bill<a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjmzmUOOKtXMS4CW9cM9rVEgRKwVyeeLx-ftv2I79j2auqbG4krJcUV2R_BUr5rOlyh_6Iay_S9s76JrxoSfhyphenhyphenOBhDBjaJryAmpTwlN9UKhAPzzWpuhKfTfbJiLO6GZ6Rpw2i46ppuGOMz3/s1600/2_tankers.jpg"><img style="float: right; margin: 0pt 0pt 10px 10px; cursor: pointer; width: 280px; height: 167px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjmzmUOOKtXMS4CW9cM9rVEgRKwVyeeLx-ftv2I79j2auqbG4krJcUV2R_BUr5rOlyh_6Iay_S9s76JrxoSfhyphenhyphenOBhDBjaJryAmpTwlN9UKhAPzzWpuhKfTfbJiLO6GZ6Rpw2i46ppuGOMz3/s320/2_tankers.jpg" alt="" id="BLOGGER_PHOTO_ID_5487236551955624594" border="0" /></a>A few days ago I heard a radio talk-show host say we should cut our dependence on foreign oil by using more wind, solar and nuclear power. While this is a popular notion, increasing our use of these sources will do <span style="font-weight: bold;">extremely little</span> to reduce our oil consumption.<br /><br />Reason: Oil-fueled power plants generate <span style="font-weight: bold;">less than 1%</span> of U.S. electricity. Most of our power is produced from domestic fossil fuels like coal and natural gas.<br /><br />According to the <a href="http://www.eia.doe.gov/cneaf/electricity/epm/table1_1.html">U.S. Energy Information Administration</a>, in the 12 months ending March 2010, about 45% of our electricity came from coal, 23% from natural gas, 20% from nuclear plants, and 7% from hydroelectric sources.<br /><br />Renewable sources like wind, solar, biomass and others contributed nearly 4% of our power.<br /><br />So where does the oil we drill or import go?<br /><br />Once again, <a href="http://www.eia.gov/dnav/pet/pet_cons_psup_dc_nus_mbbl_m.htm">the EIA to the rescue</a>. In March 2010, finished gasoline accounted for 46% of our oil usage. <a href="http://www.eia.gov/neic/infosheets/petroleumproductsconsumption.html">The rest is used</a> in the manufacture of diesel oil, jet fuel, heating fuel, asphalt, plastics, etc., etc.<br /><br />Which means if we want to reduce our dependence on oil, we need to severely curtail our use of gasoline-powered cars.<br /><br />Fuel cells, anyone?Arun Sinhahttp://www.blogger.com/profile/16448414776484904929noreply@blogger.com0tag:blogger.com,1999:blog-2850928880337197232.post-6717196428904424022010-06-19T14:12:00.005-04:002010-06-19T17:34:58.795-04:00Some Chevrolet Volt Owners May Get 240-volt Charging Stations<a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiGv0W1LiJue5q5sdYSyT0kjxq3MOZZxTiPBa3kETcu0-DlswwCVUxtmm7hNSNRGqJq2VMsPWM5JhM1btKft288LXQL_M2PzsMfbS3WX_nOBv_wxsF6qNKPir5hV1MpiepEAFkBHjk7gJuF/s1600/volt03.jpg"><img style="float: left; margin: 0pt 10px 10px 0pt; cursor: pointer; width: 259px; height: 178px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiGv0W1LiJue5q5sdYSyT0kjxq3MOZZxTiPBa3kETcu0-DlswwCVUxtmm7hNSNRGqJq2VMsPWM5JhM1btKft288LXQL_M2PzsMfbS3WX_nOBv_wxsF6qNKPir5hV1MpiepEAFkBHjk7gJuF/s320/volt03.jpg" alt="" id="BLOGGER_PHOTO_ID_5484600771156367186" border="0" /></a>When the <a href="http://www.chevrolet.com/pages/open/default/future/volt.do">Chevrolet Volt</a> goes on sale later this year as a 2011 model, about 4,400 owners will be eligible for <a href="http://www.freep.com/article/20100618/BUSINESS0101/6180469/1320/Early-Volt-buyers-may-get-charging-station">free 240-volt charging stations</a>. The stations will be funded by federal stimulus money through a program administered by the U.S. Department of Energy.<br /><br />240-volt charging stations recharge the car in about 4 hours. Standard household 120-volt outlets take about twice as long to recharge the Volt.<br /><br />The Chevrolet Volt can travel 40 miles on electrical power alone. When the electricity runs out, an onboard generator powered by gasoline recharges the batteries and keeps the car running for, as GM says, "hundreds of miles."Arun Sinhahttp://www.blogger.com/profile/16448414776484904929noreply@blogger.com0tag:blogger.com,1999:blog-2850928880337197232.post-53995720896778636432010-06-12T09:04:00.001-04:002010-06-12T09:34:39.113-04:00Clean Energy R&D Funds Should Be Tripled in U.S.When the CEOs of 7 companies like GE and Microsoft talk with one voice, people should listen.<br /><br />The <a href="http://www.americanenergyinnovation.org/">American Innovation Energy Council</a>, a council of corporate leaders, <a href="http://www.nytimes.com/gwire/2010/06/10/10greenwire-corporate-heavies-urge-tripling-us-clean-energ-10089.html">urged Congress and President Obama to triple funding for clean-energy related R&D</a> from $5 billion to $16 billion per year.<br /><br />As reported in the Times, GE's CEO Jeff Immelt said, "The world is not going to wait for the United States to lead. This is about innovation; this is about competition; this is about energy security."<br /><br />We're not leading — <a href="http://www.nuwireinvestor.com/articles/united-states-renewable-energy-sector-is-falling-behind-the-rest-54977.aspx">that's a given</a>. But not only are we not following, we're looking in the opposite direction.<br /><br />Or is it that our only hope of being competitive is waiting for <a href="http://www.torontosun.com/money/2010/06/11/14353226.html">Chinese goods to become more expensive</a>?Arun Sinhahttp://www.blogger.com/profile/16448414776484904929noreply@blogger.com0tag:blogger.com,1999:blog-2850928880337197232.post-36266258401715292402010-05-30T13:50:00.004-04:002010-05-30T15:20:31.901-04:00Solar-Powered Plane "Solar Impulse" Makes Impressive Debut FlightOn April 7, 2010, the 3,500-pound solar powered airplane <a href="http://www.solarimpulse.com/">"Solar Impulse"</a> t<a href="http://technorati.com/technology/article/solar-powered-plane-solar-impulse-has/">ook off from a Swiss military airport near the town of Payerne</a> and flew for 90 minutes.<br /><br />In the history of solar powered flight, this is a highly significant achievement.<br /><br />12,000 solar cells, 880 pounds of lithium batteries and 4 electric motors of 10 hp each got the plane off the ground and kept it aloft at an altitude of nearly a mile. The solar powered plane took off at just 30 mph, reaching an average cruising speed of 44 mph.<br /><br />Watch a video of the maiden flight:<br /><br /><object width="640" height="385"><param name="movie" value="http://www.youtube.com/v/u54lQ9jiYpk&hl=en_US&fs=1&rel=0"><param name="allowFullScreen" value="true"><param name="allowscriptaccess" value="always"><embed src="http://www.youtube.com/v/u54lQ9jiYpk&hl=en_US&fs=1&rel=0" type="application/x-shockwave-flash" allowscriptaccess="always" allowfullscreen="true" width="640" height="385"></embed></object><br /><br />And if you think the plane looks too skinny and delicate to inspire confidence about its ability to carry passengers and cargo, remember that the <a href="http://www.acepilots.com/travel/Wright_Brothers_Flyer.jpg">Wright brothers' Flyer</a> looked puny too. But it spawned leviathans like the <a href="http://en.wikipedia.org/wiki/File:Giant_planes_comparison.svg">Antonov An-225 and the Airbus A380</a>.Arun Sinhahttp://www.blogger.com/profile/16448414776484904929noreply@blogger.com0tag:blogger.com,1999:blog-2850928880337197232.post-76954155731517769202010-05-27T17:55:00.006-04:002010-05-27T20:38:15.092-04:00Why Government's Response to Oil Spill Is Different From Other DisastersWhen a bridge falls down or a natural disaster strikes, the federal government knows what to do. It has the knowledge and resources to help. It can send food, water, tents, trailers, first aid, sandbags. It can deploy crews to rebuild roads and structures. It can coordinate efforts from private relief agencies.<br /><br />But when it comes to plugging an oil spill in 5,000 feet of water, the government can't do much. It doesn't have the know-how or technology to fix the problem.<br /><br />Frustrating as it may be, the solution lies with the oil and oil services companies themselves. They have the knowledge, the experience, the equipment.<br /><br />If this were, say, a bridge that was slowly buckling for a month, the government would be able to halt the crumbling. It has engineers who could do this in their sleep.<br /><br />But a specialized field like deep-sea oil drilling? Almost all the engineers with the relevant qualifications are working in industry — not in the government.<br /><br />Which is as it should be. We can't expect governments to spend time and money developing in-house expertise in every technology. That's the domain of the private sector. This distribution of skills between the public and private sectors leads to efficient allocation of the nation's wealth and resources.<br /><br />It's only a problem when the private sector misbehaves in a way the government can't remedy. Then all the government can do is criticize, cajole and threaten.Arun Sinhahttp://www.blogger.com/profile/16448414776484904929noreply@blogger.com0tag:blogger.com,1999:blog-2850928880337197232.post-35922301162092509582010-05-02T12:08:00.004-04:002010-05-02T12:13:32.334-04:00Area Taken Up by Wind Farms<a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEh9aMEEkxxbaCoYsDZdgIbtkQWqcgsDengOo7rK6x_m7FOE6rA6DzPlGH8hjdfDi74O6ow2C2chr7bGL9ZDYciVfA5QTS6MWSW3_Z4zmiEJHoJmv6BMmsGbiLCEkCs_LyhmWAzGiV5J72jt/s1600/wind.jpg"><img style="margin: 0pt 0pt 10px 10px; float: right; cursor: pointer; width: 151px; height: 244px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEh9aMEEkxxbaCoYsDZdgIbtkQWqcgsDengOo7rK6x_m7FOE6rA6DzPlGH8hjdfDi74O6ow2C2chr7bGL9ZDYciVfA5QTS6MWSW3_Z4zmiEJHoJmv6BMmsGbiLCEkCs_LyhmWAzGiV5J72jt/s320/wind.jpg" alt="" id="BLOGGER_PHOTO_ID_5466706332037983090" border="0" /></a>Wind produces little of the U.S.'s power: <a href="http://www.eia.doe.gov/cneaf/electricity/epm/table1_1_a.html">70,761 GWh in 2009</a>, or 1.7% of <a href="http://www.eia.doe.gov/cneaf/electricity/epm/table1_1.html">all electricity generation</a>. At the same time, wind farms seem to take up huge amounts of land. So I began wondering, if we were to aim for, say, making 50% of our electricity from wind, how much of our land area would that take up?<br /><br />RenewableUK, a trade body for the UK wind and marine renewables industries, provides the answer. (There's no reason for me to believe that the UK's space requirements are different from ours.)<br /><br /><a href="http://www.bwea.com/ref/faq.html#space">According to them</a>,<br /><blockquote>To obtain 10% of our electricity from the wind would require ... 0.3% to 0.5% of the UK land area.</blockquote>They go on to say that less than 1% of this area would be used for foundations and access roads and that the other 99% could still be used for farming. By comparison, they say, 1.5% of the UK land area is covered by roads and about 77% is used for agriculture.<br /><br /><span style="font-size:85%;">Photo: National Renewable Energy Laboratory, Photographic Information Exchange.</span>Arun Sinhahttp://www.blogger.com/profile/16448414776484904929noreply@blogger.com0tag:blogger.com,1999:blog-2850928880337197232.post-24442592152472580162010-04-17T17:28:00.000-04:002010-04-17T20:56:08.254-04:00Battery-Driven LocomotivesYou knew batteries could power cars. Did you know <a href="http://www.comsol.com/industry/htmlpaper/general_electric_modeling_train_batteries/">they could also power locomotives</a>?<br /><br />Batteries can provide up to 2,000 horsepower to a locomotive. What's more, locomotives spend many minutes while dynamic braking, as opposed to cars that brake for only a few seconds at a time. The energy captured from regenerative braking can cut a locomotive's fuel use by 15%, equivalent to 25,000 – 30,000 gallons of diesel per vehicle per year, and eliminate more than 300,000 kg of CO<sub>2</sub> emissions, equivalent to that from 2,600 cars. The reduction in NO<sub>x</sub> emissions is even more significant.<br /><br />General Electric is currently modeling a sodium metal-chloride battery for use in hybrid locomotives as an alternative to the lithium and metal-hydride batteries used in cars. Key requirements for a locomotive battery are:<br /><ul><li>Higher energy densities</li><li>Ability to withstand the environment of a long-haul locomotive</li><li>Tolerance of cell failures in high-voltage strings, where batteries with failed cells continue to operate safely and effectively.</li></ul>GE has posted a video on its site about the future of battery-powered hybrid locomotives. To see it, <a href="http://www.ge.com/products_services/rail.html">click here</a>.Arun Sinhahttp://www.blogger.com/profile/16448414776484904929noreply@blogger.com0tag:blogger.com,1999:blog-2850928880337197232.post-10768408164594604412010-04-03T12:01:00.006-04:002010-04-03T13:04:18.144-04:00DOT-EPA Fuel Economy Rules - A Summary<a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiRR0YE-1iCSI6s6y38oPAn1FXXxfVawwYQS6vcndMQpK1xuah0FsbvI8L6tbXc99T0NShmB72rreL95_8nGMlnLqR2QcN5ttR9OFolaNEpyy9YnHdGFFY0MlzJ9mnRbz0djds20652UpLp/s1600/exhaust_car.jpg"><img style="margin: 0pt 0pt 10px 10px; float: right; cursor: pointer; width: 233px; height: 163px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiRR0YE-1iCSI6s6y38oPAn1FXXxfVawwYQS6vcndMQpK1xuah0FsbvI8L6tbXc99T0NShmB72rreL95_8nGMlnLqR2QcN5ttR9OFolaNEpyy9YnHdGFFY0MlzJ9mnRbz0djds20652UpLp/s320/exhaust_car.jpg" alt="" id="BLOGGER_PHOTO_ID_5455958126168912738" border="0" /></a>On April 1, 2010, the U.S. Department of Transportation and EPA <a href="http://yosemite.epa.gov/opa/admpress.nsf/d0cf6618525a9efb85257359003fb69d/562b44f2588b871a852576f800544e01%21OpenDocument">jointly announced</a> new national standards for automotive fuel efficiency and greenhouse gas reductions. Here's a summary.<br /><br /><span style="font-weight: bold;">Vehicles Covered</span><br />Passenger cars and light trucks, model years 2012 onward.<br /><br /><span style="font-weight: bold;">New Standard</span><br /><ul><li>Starting with MY 2012, improve fleet-wide fuel efficiency and lower greenhouse gas emissions about 5% each year.</li><li>By MY 2016, fleet fuel economy should be 34.1 mpg without credits for air-conditioning improvements, as required by DOT's National Highway Transportation Safety Administration rules.</li><li>By MY 2016, manufacturers must achieve a combined average vehicle emission level of 250 grams of carbon dioxide per mile.</li></ul><span style="font-weight: bold;">Potential Costs<br /></span>Building cars and light trucks that achieve the standard will cost carmakers an extra $52 billion for MY 2012 through 2016.<br /><span style="font-weight: bold;"><br />Potential Savings</span><br /><ul><li>$3,000 in lower fuel costs for each buyer of a covered vehicle, over that vehicle's life.</li><li>Nationally, 1.8 billion barrels of oil and nearly 1 billion tons of greenhouse gases over the lives of covered vehicles.</li></ul><span style="font-weight: bold;">Why the Executive Branch of the Government Loves the New Standard</span><br /><ul><li>The savings.</li><li>Realizing one of the Obama Administration's first major directives.</li><li>Clearer rules for all automakers, instead of three standards (DOT, EPA, and a state standard).</li></ul><span style="font-weight: bold;">Why the Legislative Branch of the Government Isn't Too Thrilled</span><br />Some senators say the rules could hurt the economy, and <a href="http://www.businessweek.com/news/2010-04-01/u-s-releases-final-fuel-economy-rule-for-vehicles-update1-.html">want to curb EPA action</a>.<br /><br /><span style="font-weight: bold;">Who Else Hates It</span><br />The <a href="http://www.api.org/Newsroom/statemnt-epafuelstd.cfm">American Petroleum Institute. </a><br /><br /><span style="font-weight: bold;">Who Else Loves It</span><br />Canada. On the same day as the U.S. action, Environment Canada <a href="http://www.ec.gc.ca/default.asp?lang=En&n=714D9AAE-1&news=B1DDFE4D-5147-46F9-BA97-BA1BDDC3B7A6">released proposed regulations</a> to reduce greenhouse gas emissions from new vehicles and which would harmonize with those of the U.S. starting with MY 2011.Arun Sinhahttp://www.blogger.com/profile/16448414776484904929noreply@blogger.com0tag:blogger.com,1999:blog-2850928880337197232.post-21283690063127901572010-03-27T09:29:00.002-04:002010-03-27T09:36:52.117-04:00Earth Hour at 8:30 pm Local Time Today<a href="https://www.myearthhour.org/home">Earth Hour</a> returns at 8:30 pm (2030 hours) local time today.<br /><br />Last year, nearly 1 billion people in 4,100 cities in 87 countries on 7 continents celebrated Earth Hour. Landmarks that went dark for an hour included:<br /><ul><li>Empire State Building</li><li>Brooklyn Bridge</li><li>Broadway Theater Marquees</li><li>Las Vegas Strip</li><li>United Nations Headquarters</li><li>Golden Gate Bridge</li><li>Seattle’s Space Needle</li><li>Church of Latter-Day Saints Temple</li><li>Gateway Arch in St. Louis</li><li>Great Pyramids of Giza</li><li>Acropolis and Parthenon in Athens</li><li>Christ the Redeemer Statue in Rio de Janeiro</li><li>St. Peter’s Basilica in Vatican City</li><li>Big Ben and Houses of Parliament in London</li><li>Elysee Palace and Eiffel Tower in Paris</li><li>Beijing’s Birds Nest and Water Cube</li><li>Symphony of Lights in Hong Kong</li><li>Sydney’s Opera House</li></ul>The Earth Hour website has some <a href="http://www.myearthhour.org/earth-hour-video">cool videos</a>. Here's a slideshow of Earth Hour 2009:<br /><br /><object width="640" height="385"><param name="movie" value="http://www.youtube.com/v/peEf-4xHdeI&color1=0xb1b1b1&color2=0xcfcfcf&hl=en_US&feature=player_embedded&fs=1"><param name="allowFullScreen" value="true"><param name="allowScriptAccess" value="always"><embed src="http://www.youtube.com/v/peEf-4xHdeI&color1=0xb1b1b1&color2=0xcfcfcf&hl=en_US&feature=player_embedded&fs=1" type="application/x-shockwave-flash" allowfullscreen="true" allowscriptaccess="always" width="640" height="385"></embed></object>Arun Sinhahttp://www.blogger.com/profile/16448414776484904929noreply@blogger.com0tag:blogger.com,1999:blog-2850928880337197232.post-2159541789354972062010-03-25T22:04:00.003-04:002010-03-25T22:57:57.922-04:00Micro Hydro Power From the FlipwingA Seattle-based company called <a href="http://www.hydrovolts.com/">Hydrovolts</a> has been winning awards for its miniature turbine that you can drop into streams, canals, and pretty much any place that has a steady flow of water.<br /><br />The turbine, brand named Flipwing, will be produced in three sizes. The smallest will be about the size of a 2-drawer filing cabinet and the largest will be about 2 x 2 x 6 meters. It can be installed in the water stream vertically or horizontally.<br /><br />The Flipwing's blades swing open on the reverse upstream stroke, presenting their edge to the current. Thus the kinetic energy of the water flow is used almost entirely in turning the blades in the downstream direction.<br /><br />Hydrovolt's website is a bit opaque about the amount of electricity the Flipwing produces. Using an average market price of electricity of $0.11 per kWh, the site says the turbine can generate, in a 2m/sec current, $1,400 worth of electricity per year. By my calculations, that means it can make 12.7 MWh of electricity annually.<br /><br />Here's a video of a small Flipwing unit in operation in a stream. Hydrovolt has several more videos on its YouTube channel:<br /><br /><object width="480" height="385"><param name="movie" value="http://www.youtube.com/v/1UNe4hff_IA&hl=en_US&fs=1&"><param name="allowFullScreen" value="true"><param name="allowscriptaccess" value="always"><embed src="http://www.youtube.com/v/1UNe4hff_IA&hl=en_US&fs=1&" type="application/x-shockwave-flash" allowscriptaccess="always" allowfullscreen="true" width="480" height="385"></embed></object>Arun Sinhahttp://www.blogger.com/profile/16448414776484904929noreply@blogger.com0tag:blogger.com,1999:blog-2850928880337197232.post-76372796391506145722010-03-03T22:16:00.004-05:002010-03-03T22:39:27.566-05:00Wallpaper That Emits LightYou've heard of the incandescent light bulb, and the compact fluorescent light bulb, and the LED light bulb. How about a source of light that isn't a bulb, but an entire <a href="http://www.clickgreen.org.uk/news/national-news/121005-revolutionary-light-emitting-wallpaper-could-soon-replace-light-bulbs.html">wall that emits light</a>?<br /><br /><a href="http://www.lomox.co.uk/">LOMOX</a>, a company that develops <a href="http://www.howstuffworks.com/oled.htm">OLED</a> (Organic Light Emitting Diode) technologies, has built OLED materials that could be coated onto a film, which could in turn be attached to a wall. This would turn the entire wall into a light source.<br /><br />A light source that emits natural-looking light with a brightness of 150 lumens/watt.<br /><br />The film would consume just 3 to 5 volts of electricity, which means you could power it with a battery. LOMOX says it has overcome a major drawback of OLED technology: short product lifetimes.<br /><br />The company expects its lighting technology to reach the market in 2012.<br /><br /><span style="font-size:85%;">Via GlobalSpec.</span>Arun Sinhahttp://www.blogger.com/profile/16448414776484904929noreply@blogger.com0tag:blogger.com,1999:blog-2850928880337197232.post-4267832444202882982010-02-27T14:43:00.003-05:002010-02-27T15:13:47.084-05:00Solar Cells Made From Common SubstancesFrom CNET's Green Tech: Researchers at IBM have written a paper describing <a href="http://news.cnet.com/8301-11128_3-10451641-54.html">a solar cell made from common materials</a> like copper, zinc, tin and sulfur or selenium (CZTS).<br /><br />Conventional silicon and thin-film solar cells are made from scarce or expensive materials that limit production capacity and improvements, according to IBM. Solar cells made from abundant elements have no such cost or production constraints.<br /><br />The cells IBM describes convert only 9.6% of the solar energy falling on them into electrical energy. While this is 40% higher than what CZTS solar cells have achieved to date, it's far lower than the efficiencies of polysilicon and even thin-film solar cells.<br /><br />However, IBM's cells use only small amounts of material. If the cells' efficiency were pushed up to 12%, they would be commercially viable alternatives to current products.Arun Sinhahttp://www.blogger.com/profile/16448414776484904929noreply@blogger.com0tag:blogger.com,1999:blog-2850928880337197232.post-27371033665794761212010-02-27T10:43:00.003-05:002010-02-27T14:27:03.403-05:00Marines Target Solar Energy Development on Front LinesIn remote battle locations, electronic devices used for communications and targeting run on electricity from generators. Transporting fuel to these places is risky and expensive. The Navy is therefore <a href="http://defensesystems.com/articles/2010/03/11/defense-it-3-greens.aspx?admgarea=DS">focusing on renewable energy to power computers in the field</a>.<br /><br />During the first quarter of this year, the Navy will start procuring renewable power systems made up of solar panels and rechargeable batteries. Known as the Ground Renewable Expeditionary Energy System (Greens), it can provide an average continuous output of 300 watts of electricity, with peaks of up to 1 kW.<br /><br />According to the report in <a href="http://defensesystems.com/">Defense Systems</a>, that's enough to power most of the essential communications and targeting electronics that Marine forces would need in remote locations.<br /><br />Last October, Navy Secretary Ray Mabus announced <a href="http://www.2009military.com/military-news-story.cfm?textnewsid=3976">five energy goals through the year 2020</a>. One of the goals is to ensure that by the end of the next decade, at least 40% of the Navy's total energy consumption comes from alternative sources.Arun Sinhahttp://www.blogger.com/profile/16448414776484904929noreply@blogger.com0tag:blogger.com,1999:blog-2850928880337197232.post-2691866786992839592010-02-20T18:27:00.013-05:002010-02-27T10:15:39.345-05:00How Nuclear Power Works<table style="width: 232px; height: 170px;" align="right"><tbody><tr align="left"><td><a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhjNvIBX_O-eTl569cuUz3d6ShRUcCl_lBzH9u6zCqzGmL0RllUnq16cHr6un0ZzcL_g0h3tDQpY3M6x0ETj55B0JStgnxnF3TI2awSLTGjb2jdMz4qgQetjA4eRxtFxLsdx6DSQ3Gt_PfW/s1600-h/nuclear+cooling+tower.jpg"><img style="margin: 0pt 0pt 10px 10px; float: right; cursor: pointer; width: 232px; height: 166px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhjNvIBX_O-eTl569cuUz3d6ShRUcCl_lBzH9u6zCqzGmL0RllUnq16cHr6un0ZzcL_g0h3tDQpY3M6x0ETj55B0JStgnxnF3TI2awSLTGjb2jdMz4qgQetjA4eRxtFxLsdx6DSQ3Gt_PfW/s320/nuclear+cooling+tower.jpg" alt="" id="BLOGGER_PHOTO_ID_5440499784925368882" border="0" /></a></td></tr><tr align="left" style="font-family:arial;"><td style="padding-left: 15px;"><span style="font-size:85%;">A hyperboloid cooling tower at a nuclear power plant. The tower transfers excess heat from the water to the atmosphere.</span></td></tr></tbody></table>A nuclear power plant generates electricity by heating water to produce steam, which drives a turbine. The heat is created by splitting uranium atoms.<br /><br /><a href="http://www.chemicool.com/elements/uranium.html">Uranium</a> is the heaviest naturally-occurring atom in nature. Its nucleus has 92 <a href="http://hyperphysics.phy-astr.gsu.edu/HBASE/particles/proton.html">protons</a> and, in its most common form, 146 <a href="http://www.historyoftheuniverse.com/neutron.html">neutrons</a>, giving it a mass number of 238. It is indicated by the symbol <sup>238</sup>U<sub>92</sub>, or just <sup>238</sup>U. For our purposes, we'll refer to it as U-238.<br /><br />Over 99% of uranium is U-238. Another 0.7% of the element is of a form (or <a href="http://www.colorado.edu/physics/2000/isotopes/index.html">isotope</a>) that has not 146 but 143 neutrons. This is U-235, and is of chief interest to us, because this is the form that can be split manually and that discharges heat on splitting.<br /><br />Uranium extracted from the earth must be enriched until it contains 2% to 3% of U-235. (Weapons-grade uranium is enriched to 90% U-235.)<br /><br />The U-235 is placed in a container in a nuclear reactor, where it absorbs neutrons. On being hit by a free neutron, the uranium atom splits into two smaller atoms (typically krypton and barium) and releases two to three neutrons and a huge amount of energy as heat. This event is known as fission.<br /><br />Each U-235 atom that undergoes fission releases 200 million electron volts, or MeV, of energy. Now 1 MeV is extremely tiny, so tiny you would never feel it. But one gram of U-235 has 2,562,553,191,489,360,000,000 atoms. When all those atoms split, the electron volts emitted add up to a lot of energy (you do the math!). Actually, one gram of U-235 produces the <a href="http://www-istp.gsfc.nasa.gov/stargaze/SnucEnerA-5.htm">same amount of energy as 5.16 tons of TNT</a>.<br /><br />Obviously, we can't have that. The fission of uranium must be controlled. Fortunately, there's a way to do that.<br /><br />Ordinary water, heavy water or graphite are used to slow the neutrons down, and rods of cadmium or barium are inserted into the container to absorb neutrons and thus control their concentration.<br /><br />As a result, all that fission energy is safely channeled toward making steam, which powers the turbine, thereby generating electricity.<br /><br />And if you live in Connecticut, know that about 38% of your electricity comes from nuclear power.Arun Sinhahttp://www.blogger.com/profile/16448414776484904929noreply@blogger.com0tag:blogger.com,1999:blog-2850928880337197232.post-7882018988963197732010-02-13T21:45:00.003-05:002010-02-17T22:12:23.293-05:00Renewable Energy Industry Groups Urge Stronger U.S. Renewable Energy StandardCEOs representing renewable energy companies in the U.S. <a href="http://awea.org/newsroom/pdf/2-4-10_RES_Alliance_for_Jobs_release.pdf">released on Feb. 4, 2010, a study (pdf)</a> that showed increasing our renewable electricity standard to 25% by 2025 would support 274,000 jobs.<br /><br />The study was released by <a href="http://www.res-alliance.org/">RES Alliance for Jobs</a>, a coalition of businesses and organizations that support Congressional enactment of a strong federal Renewable Electricity Standard (RES).Arun Sinhahttp://www.blogger.com/profile/16448414776484904929noreply@blogger.com0tag:blogger.com,1999:blog-2850928880337197232.post-69379618539251360522010-02-03T22:08:00.002-05:002010-02-03T22:58:12.689-05:00Battery Than Can Produce Utility-Scale PowerThink of an aluminum plant running in reverse, generating electricity instead of consuming it.<br /><br />That's the concept behind a new <a href="http://web.mit.edu/newsoffice/2009/liquid-battery.html">stationary battery large enough to produce utility-scale power</a>, a technology being developed by MIT Professor David Sadoway.<br /><br />The battery produces power by making a sandwich out of 2 layers of liquid metal alloy with a layer of a salt in between, and then placing the entire sandwich in an electrolyte. Ions flow from one metal layer through the electrolyte to the other layer, generating electricity. The whole system is maintained at 700° C.<br /><br /><a href="http://arpa-e.energy.gov/NewsMedia/News/tabid/83/ItemId/13/vw/1/Default.aspx">Sadoway's project has already received a grant</a> of nearly $7 million over 5 years from the Department of Energy's <a href="http://arpa-e.energy.gov/">Advanced Research Projects Agency-Energy</a>, or ARPA-E. Soon after that, the French oil company Total <a href="http://www.total.com/en/about-total/news/news-940500.html&idActu=2174">announced a $4-million research agreement</a> with MIT to jointly develop a smaller version of the battery.<br /><br />In its press release announcing the grant for the battery (along with names of other grant recipients), ARPA-E said:<br /><blockquote>If successful, this battery technology could revolutionize the way electricity is used and produced on the grid...</blockquote>Arun Sinhahttp://www.blogger.com/profile/16448414776484904929noreply@blogger.com0tag:blogger.com,1999:blog-2850928880337197232.post-67315769796041273872010-01-30T15:20:00.001-05:002010-01-30T17:06:14.880-05:00Massive Gains Possible from Energy Efficiency, Says McKinsey & Co.There is a McKinsey report out that shows the <a href="http://www.mckinsey.com/clientservice/electricpowernaturalgas/US_energy_efficiency/">potential savings of non-transportation energy in the U.S.</a> simply through efficiency.<br /><br />According to the report, we could (emphasis mine):<br /><blockquote>reduce annual non-transportation energy consumption by roughly 23 percent by 2020, <span style="font-weight: bold;">eliminating more than $1.2 trillion in waste</span> – well beyond the $520 billion upfront investment (not including program costs) that would be required. The reduction in energy use would also result in the <span style="font-weight: bold;">abatement of 1.1 gigatons of greenhouse gas emissions annually</span> – the equivalent of taking the entire U.S. fleet of passenger vehicles and light trucks off the roads.</blockquote>For a pdf copy of the report's executive summary, <a href="http://www.mckinsey.com/clientservice/electricpowernaturalgas/downloads/US_energy_efficiency_exc_summary.pdf">click here</a>.<br /><br />For the full 165-page report, <a href="http://www.mckinsey.com/clientservice/electricpowernaturalgas/downloads/US_energy_efficiency_full_report.pdf">click here</a>.Arun Sinhahttp://www.blogger.com/profile/16448414776484904929noreply@blogger.com0tag:blogger.com,1999:blog-2850928880337197232.post-13028655995599134282010-01-23T21:37:00.001-05:002010-01-23T22:53:25.441-05:00Sustainable Packaging Using BioplasticsJust about everything we buy is covered in plastic packaging at some stage of its production cycle. With oil prices rising and consumer demand for sustainable packages growing, companies are turning their attention to packaging made out of bioplastics.<br /><br />The benefit of bioplastics is, of course, that they <a href="http://maps.grida.no/go/graphic/how-long-does-it-take-for-some-commonly-used-products-to-biodegrade">degrade in the environment</a>.<br /><br />As the video below explains, bioplastics can be made from a range of plants such as sugarcane, wheat, tapioca, potato and soy.<br /><br />Using vegetable products in packaging, however, means they have to be diverted from the food supply — which could lead to food shortages and higher prices. So chemical manufacturers are also looking into making bioplastics out of agricultural waste.<br /><br /><object width="425" height="344"><param name="movie" value="http://www.youtube.com/v/1XPXM4JRfec&hl=en_US&fs=1&"></param><param name="allowFullScreen" value="true"></param><param name="allowscriptaccess" value="always"></param><embed src="http://www.youtube.com/v/1XPXM4JRfec&hl=en_US&fs=1&" type="application/x-shockwave-flash" allowscriptaccess="always" allowfullscreen="true" width="425" height="344"></embed></object>Arun Sinhahttp://www.blogger.com/profile/16448414776484904929noreply@blogger.com0tag:blogger.com,1999:blog-2850928880337197232.post-81619926970771299682010-01-23T17:00:00.006-05:002010-01-23T18:32:01.884-05:00Plastic Solar Cells Provide Light in Villages Lacking ElectricityPhotovoltaic solar cells have long been seen as the most efficient source of inexpensive lighting in rural villages that lack electricity.<br /><br />Now a scientist at Denmark's Risø National Laboratory for Sustainable Energy has built <a href="http://spectrum.ieee.org/green-tech/solar/plastic-solar-cells-roll-into-unlit-villages/0">a lamp made of a flexible plastic sheet</a> on which are embedded a photovoltaic (PV) solar cell, an LED light source, a lithium battery, a diode and copper circuitry.<br /><br />The rectangular plastic sheet is about the size of an overhead-projector transparency (<a href="http://www.officemax.com/office-supplies/presentation-equipment-supplies/transparency-film">yes, they still exist</a>). Snapping together the fasteners on two corners of the sheet results in a funnel-shaped structure that produces directional light.<br /><br />The solar PV cell charges the lithium battery during the day so the battery can power the LED bulbs at night. The cell is made of organic polymers and carbon nanostructures. It is inexpensive to produce but converts only 1% to 2% of the energy falling on it to electricity.<br /><br />Sure, the light is dim, but the price ($27 for now) is about half what a villager would pay for a year's worth of kerosene to fuel an existing lamp. Each plastic sheet/lamp would last for a year. After all, you can flex a plastic sheet only so many times before it cracks.<br /><br />Frederik Krebs, the lamp's inventor, hopes to start selling them this year. The market consists of 1.5 billion people in villages in Asia, Africa and Latin America that don't have electricity. Many of these places are so inaccessible they may never be on the grid.<br /><br />If you were wondering whether <a href="http://www.amazon.com/Coleman-Battery-Powered-Lantern-Personal/dp/B0009PUQ6O/ref=pd_sim_sg_1">an ordinary battery-powered lamp</a> might not cost less, the answer is no. The batteries would run out after about 20 hours, which means each customer would have to buy hundreds of batteries to keep the lamp lit for a few hours every night of the year.Arun Sinhahttp://www.blogger.com/profile/16448414776484904929noreply@blogger.com0tag:blogger.com,1999:blog-2850928880337197232.post-77219730619383628442010-01-16T11:01:00.004-05:002010-01-16T12:00:33.692-05:00Internet's Power Usage Could Be Reduced 99.9%Smarter data coding could <a href="http://www.newscientist.com/article/dn18377-worlds-communications-network-due-an-energy-diet.html?DCMP=OTC-rss&nsref=online-news">cut the energy used by the world's data networks 99.9% by 2015</a>.<br /><br />The New Scientist reports that Bell Labs has launched a coalition of information and communications industry experts called <a href="http://www.greentouch.org/">Green Touch</a>. The consortium has the vision of "significantly reducing the carbon footprint of ICT [information and communications technology] devices, platforms and networks."<br /><br /><span style="font-weight: bold;">Smarter Coding Cuts Through Noise</span><br /><br />Green Touch members have identified many approaches to cutting energy use by data communications networks:<br /><ul><li>Today's networks use high levels of power to rise above the noise inherent in communications channels. Bell Labs plans to develop low-power networks by implementing a code that detects low-power signals and ignores the noise.<br /><br /></li><li>An <a href="http://www.mit.edu/%7Emedard/medard.html">MIT engineer</a> is looking at ways to bundle data traveling over similar routes, which will reduce traffic on trunk routes that consume large amounts of power.<br /><br /></li><li>A <a href="http://ww2.ee.unimelb.edu.au/staff/rst/">professor at the University of Melbourne, Australia</a>, will consider "ways to make modems and phones go into a sleep mode when not in use — but from which they can wake up quickly." <br /><br /></li><li>Other efforts will focus on power savings in memory and displays, and on changing user behavior.</li></ul><br />Generating the power for our telephone, internet and cell phone networks releases 300 million tons of carbon dioxide into the air every year, says the head of research for Bell Labs. That's equal to the emissions from 50 million cars, or one of every 5 cars registered in the U.S.<br /><br />Imagine the reduction in air pollution if 99.9% of those cars — or 49.95 million cars — were taken off the road.Arun Sinhahttp://www.blogger.com/profile/16448414776484904929noreply@blogger.com0tag:blogger.com,1999:blog-2850928880337197232.post-91008726194714865452010-01-09T19:38:00.006-05:002010-01-09T20:42:40.408-05:00Smog Standard Strengthened By EPA<a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgYOYuaqlzimTHwag2dLgJzGM8SF1bqr7TEN7ARBmTk6Yvmn6hfY4n9aGoM2gbdHmDhbEMjXetQve9zG52oCb-6vwiS_LietYjw2RevWA-j7jArh2Cf47QKayxZ3qqOgmJmeiBrDKwP-ahT/s1600-h/smog_los_angeles.jpg"><img style="margin: 0pt 10px 10px 0pt; float: left; cursor: pointer; width: 306px; height: 128px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgYOYuaqlzimTHwag2dLgJzGM8SF1bqr7TEN7ARBmTk6Yvmn6hfY4n9aGoM2gbdHmDhbEMjXetQve9zG52oCb-6vwiS_LietYjw2RevWA-j7jArh2Cf47QKayxZ3qqOgmJmeiBrDKwP-ahT/s320/smog_los_angeles.jpg" alt="" id="BLOGGER_PHOTO_ID_5424920434561925138" border="0" /></a>The EPA is proposing to steeply <a href="http://yosemite.epa.gov/opa/admpress.nsf/d0cf6618525a9efb85257359003fb69d/d70b9c433c46faa3852576a40058b1d4%21OpenDocument">lower the existing standard for emissions</a> of particles that cause ground-level ozone, better known as smog.<br /><br />According to the EPA, "Ground-level ozone forms when emissions from industrial facilities, power plants, landfills and motor vehicles react in the sun."<br /><br />Under the proposed "primary" smog standard, emissions would be limited to between 0.060 and 0.070 parts per million (ppm) in eight hours. A separate "secondary" standard would vary with the seasons and protect plants and trees. The agency did not say what this standard would be.<br /><br />The new smog standard replaces the 0.075 ppm limit the agency set in March 2008.<br /><br />The agency estimates that implementing the new smog standard would cost industry $19 billion to $90 billion. But its benefits to human health would range from $13 billion to $100 billion, mainly from reduced premature deaths, aggravated asthma and bronchitis cases, and hospital and emergency room visits. Another benefit to society from the lower smog standard: fewer people missing work and school days because of ozone-related symptoms.<br /><br />“Smog in the air we breathe poses a very serious health threat, especially to children and individuals suffering from asthma and lung disease. It dirties our air, clouds our cities, and drives up our health care costs across the country,” said EPA Administrator Lisa P. Jackson. “Using the best science to strengthen these standards is a long overdue action that will help millions of Americans breathe easier and live healthier.”<br /><br />Children are at the greatest risk from ozone, the agency said, because their lungs are still developing, they are most likely to be active outdoors, and they are more likely than adults to have asthma.<br /><br />The public may comment on the smog standards for 60 days after the proposal is published in the <a href="http://www.gpoaccess.gov/fr/">Federal Register</a>.<br /><br /><a href="http://www.nytimes.com/2010/01/08/science/earth/08smog.html">According to the New York Times</a>, under the current smog standard of 0.075 ppm,<br /><blockquote>322 counties of the 675 that monitor ozone levels are out of compliance. If the 0.070 limit is adopted, 515 counties would be out of compliance. Only 15 of the 675 monitored counties now meet the 0.060 standard.</blockquote>The Times reports that the agency expects to issue a final rule in August. The new rules would be phased in between 2014 and 2031.Arun Sinhahttp://www.blogger.com/profile/16448414776484904929noreply@blogger.com0tag:blogger.com,1999:blog-2850928880337197232.post-24693842111099215542010-01-06T22:52:00.003-05:002010-01-06T23:11:25.127-05:00Coal Fly Ash Spill in TVA Greater Than Waste Released in All U.S. RiversThe <a href="http://www.tennessean.com/article/20091213/COLUMNIST0106/912130367/1008/OPINION01">coal fly ash spilled</a> at the Tennessee Valley Authority's Kingston power plant on Dec. 22, 2008, carried toxic metals like arsenic, mercury and barium.<br /><br />According to data from the EPA, the amount of metal in that one spill <a href="http://www.tennessean.com/article/20091209/NEWS0201/912090397/1009/NEWS01">exceeded what was released into rivers by power plants throughout the country during the entire year</a>.<br /><br />The EPA estimated that 2.66 million lbs. (1.2 million kg) of 10 toxic metals flowed into the Emory River.<br /><br />Meanwhile, area residents <a href="http://www.tennessean.com/apps/pbcs.dll/article?AID=2009912230387">filed hundreds of lawsuits</a> against the TVA before the 1-year deadline expired for personal injury claims.Arun Sinhahttp://www.blogger.com/profile/16448414776484904929noreply@blogger.com0tag:blogger.com,1999:blog-2850928880337197232.post-58988266669800471472010-01-02T09:13:00.004-05:002010-01-02T09:38:58.235-05:00Paper or Plastic Shopping Bags? In D.C., That'll Be an Extra Nickel, Please<a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhp-FtZ0EOHL5yv6weYsb_4eacmTSu5aEEvDSin9Opw10jqSNg51JjW51HU9JXTHwPHZc3EgT1V7y2SJX90n5GwRIPemYp_4aub0VzlJ0mKZMTpyH2J2Uj7rBa-mYPR3J67lZj79WvUuwpp/s1600-h/DC_plastic_bag.jpg"><img style="margin: 0pt 0pt 10px 10px; float: right; cursor: pointer; width: 131px; height: 175px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhp-FtZ0EOHL5yv6weYsb_4eacmTSu5aEEvDSin9Opw10jqSNg51JjW51HU9JXTHwPHZc3EgT1V7y2SJX90n5GwRIPemYp_4aub0VzlJ0mKZMTpyH2J2Uj7rBa-mYPR3J67lZj79WvUuwpp/s320/DC_plastic_bag.jpg" alt="" id="BLOGGER_PHOTO_ID_5422151821564498130" border="0" /></a>Washington, D.C., has started imposing a <a href="http://green.dc.gov/green/cwp/view%2Ca%2C1248%2Cq%2C463102.asp">5 cent fee on plastic and paper bags at businesses that sell food or liquor</a>. The fee went into effect on Jan. 1, 2010.<br /><br />The extra charge on each bag is expected to generate $3.6 million for the city in its first year. Three to four cents of each nickel collected will be spent to clean up the Anacostia River.<br /><br />Reactions from D.C. residents ranged from enthusiasm to incredulity.<br /><br />The Washington Post says <a href="http://www.washingtonpost.com/wp-dyn/content/article/2010/01/01/AR2010010101673.html?hpid=sec-metro">it's one of the toughest measures in the country.</a> Neighboring states Maryland and Virginia may introduce similar laws this year.<br /><br />Last year, <a href="http://www.envirobuzz.net/2009/08/seattle-rejects-20-cent-disposable-bag.html">Seattle residents voted against a 20-cent per bag tax</a>.<br /><br />Could a similar tax be coming to your city or state? Maybe. Sometimes, an avalanche begins with one pebble rolling down the hill.Arun Sinhahttp://www.blogger.com/profile/16448414776484904929noreply@blogger.com0tag:blogger.com,1999:blog-2850928880337197232.post-63024242600886329822009-12-30T18:34:00.009-05:002009-12-30T19:37:41.148-05:00Large Dams Lead to More Rainfall<table style="width: 320px; height: 120px;" align="right"><tbody><tr align="right"><td><a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhRZCHCkk_ntUskeGEhw9HrqKvXPvosJhnhL5BwnM0KYluUBHzue6Z9KWCApZexSONCDEfpplB5gZRoEtzEUGDGtRCJY31p0fHxVC3DowyoWMqfluakLaKGqe9taPDF-U3WFv0My0bc6Zch/s1600-h/Dam.jpg"><img style="margin: 0pt 0pt 10px 10px; float: right; cursor: pointer; width: 320px; height: 100px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhRZCHCkk_ntUskeGEhw9HrqKvXPvosJhnhL5BwnM0KYluUBHzue6Z9KWCApZexSONCDEfpplB5gZRoEtzEUGDGtRCJY31p0fHxVC3DowyoWMqfluakLaKGqe9taPDF-U3WFv0My0bc6Zch/s320/Dam.jpg" alt="" id="BLOGGER_PHOTO_ID_5421189504716640258" border="0" /></a></td></tr><tr align="left"><td> <span style="font-size:85%;"><span style="font-family:arial;">Photo: ClaudioT.</span></span></td></tr></tbody></table>From the Things You Never Thought Of dept.: <a href="http://www.newsweek.com/id/228574">Dams lead to higher rainfall and more floods.</a><br /><br />Scientists from the <a href="http://www.tntech.edu/">Tennessee Technological University</a> and the <a href="http://www.colorado.edu/">University of Colorado, Boulder</a>, explain why large dams bring more rain.<br /><br />First, the reservoir behind the dam produces excessive evaporation that falls to the earth as rain. This seems obvious.<br /><br />But what's more, says the Newsweek article that reported on the finding, "dams increase atmospheric instabilities in the vertical profile of temperature and humidity."<br /><br />The increased instability "enhances the amount of convective energy in the air above the reservoir." That means more thunderstorms of greater intensity than before. That, in turn, means higher and more frequent floods than engineers had calculated when they built the dam.<br /><br />And that, say the scientists, "...raises concerns about dam safety."Arun Sinhahttp://www.blogger.com/profile/16448414776484904929noreply@blogger.com0