Courtesy ksoTalk of nuclear power has been brought back into the spotlight, especially after the discovery of Iran’s uranium enrichment plant last September. A solution to the debate about whether countries should even have the capability of enriching uranium (the process required for attaining both nuclear energy and nuclear weapons) was posed more than 50 years ago by President Eisenhower. Eisenhower suggested that various countries should allocate uranium from their stockpiles for peaceful pursuits (i.e. nuclear energy). At the time it wasn’t received very well, but a recent BBC article reported that this vision has been renewed. As of November of last year, the United Nation’s International Atomic Energy Agency (IAEA) successfully negotiated with Russia to store 120 tonnes of nuclear fuel in a plant in Angarsk (a city in the south central-ish part of Russia). In 2010, similar arrangements are said to be made with Kazakhstan. The idea is to get developing countries that are thinking about using nuclear energy in the future to join in this program, eliminating their need to enrich their own uranium.
All of this got me thinking about how nuclear energy actually works. It turns out that nuclear power plants are not that different from regular coal-burning power plants. Both plants heat water to produce pressurized steam. This steam then drives a turbine, which spins a generator to produce electricity. The only difference between the plants is how the water is heated. Coal-burning plants…well, burn coal (fossil fuels) to produce the heat, while nuclear plants rely on nuclear fission. This is where nuclear power gets really cool!
So atoms are made up of protons, neutrons, and electrons; protons are positively charged, neutrons carry no charge, and electrons are negatively charged. Atoms have an equal number of protons and electrons (making the atom, itself, electrically neutral), but the number of neutrons can vary. Atoms of the same element with a different number of neutrons are called isotopes. The isotope of uranium that is needed for nuclear fission, and therefore, nuclear energy, is Uranium-235. This isotope is unique because it can undergo induced fission, which means its nucleus can be forced to split. This happens when a free neutron runs into the nucleus of U-235.
Courtesy wondigamaU-235 absorbs the neutron, becomes unstable, and breaks into two new nuclei. In the process, two or three neutrons are also thrown out. All of this happens in a matter of picoseconds (0.000000000001 seconds)! The neutrons that are released in this reaction can then go and collide with other on-looking U-235 atoms, causing a huge chain reaction (much like this). The amount of energy released when this happens is incredible- a pound of highly enriched uranium has about the same energy as a million gallons of gasoline. This energy comes from the fact that the products of the fission (the two resulting nuclei and the neutrons that fly off), together, don’t weigh as much as the original U-235 atom. This weight difference is converted directly into energy. It’s this energy that is used to heat the water that creates the steam, which turns the turbine that spins the generator, that produces power in the nuclear reactor that Jack built.
On the plus side, with nuclear power there wouldn’t be a reliance on fossil fuels. Nuclear power plants are cleaner because they don’t emit as much carbon dioxide as traditional coal-burning and natural gas plants. However, there are some downsides as well. Mining uranium is not a clean process, transporting nuclear fuel creates a risk of radioactive contamination, and then there’s the whole issue with what to do with the still-dangerous nuclear waste once the fuel has been used up.
Whether or not we should increase our nuclear power program is still debatable, but one thing I do know is that the science behind it is fascinating!
Courtesy toolmantimHere’s an article about a paper airplane virtuoso who’s trying to break the world’s record (held by himself) for keeping a hand-launched paper plane in the air. Engineer Takuo Toda of Japan not only wants to beat his old record of 27.9 seconds – set last April in Hiroshima – he’s also set his sights on achieving the nearly impossible - breaking the 30 second barrier. Actually, the record time of 27.9 seconds should require an asterisk in the record books since it was set using a paper plane with tape on it. The paper-only airplane record – using a single sheet of uncut paper - is 26.1 seconds, and Toda holds that one, too. This guy seems to be the undisputed king of paper airplanes, but I'm sure somebody out there can show him a thing or two. Check out some of the links below and maybe it can be you.
MORE ABOUT PAPER AIRPLANES
More about paper airplane aerodynamics
Build your own paper airplane (by former record holder Ken Blackburn
Build the best paper airplane
How to build 10 paper airplanes with animated instructions no less
Even more paper airplane designs
Courtesy Rich Anderson
Refrigerators today are bigger than in the 70s but use 75% less energy. This happened because of stricter energy efficiency standards. Efficiency standards can save more energy than current wind, solar, and geothermal energy sources combined!
This week at the United Nations' summit on climate change, U.S. Department of Energy (DoE) Secretary, Steven Chu, unveiled a $350-million investment plan to bring to the developing world everything from efficient refrigerators to solar lanterns.
Climate Renewables and Efficiency Deployment Initiative (Climate REDI) is a $350-million investment by major economies, including $85 million from the U.S., to bring everything from efficient refrigerators to solar lanterns to the developing world.
"The energy savings from refrigerators is greater than all U.S. renewable energy generation—all the wind, solar thermal and solar photovoltaics—just the refrigerators," Chu said in a speech announcing the initiative, noting the refrigerators also cost less. "Energy efficiency is truly a case where you can have your cake and eat it too. [But] it was driven by standards; it didn't happen on its own."
Source: Scientific American
U.S. Unveils a $350-Million Energy-Efficiency Initiative at Copenhagen
Courtesy kevjblackThe Large Hadron Collider, the LHC, the World Destroyer, the Hula Hoop of God, the RC Matchbox Racetrack of Zeus, the Contraceptive Ring of Gaia herself… has been turned on.
You remember how concerned you were about this, right? You were worried that, based on what that friend said and what you read on that webpage, the activation of the LHC could be the end of the world, if not the universe.
Well, I know you’re nervous about what you might find, but I think there’s no avoiding it—it’s time for our regular self-check. I’ll walk you through it.
Stand up, and place your arms at your sides, palms in. Move your hands back and towards each other, keeping the palms facing in. When your hands have nearly met behind you, pull them forward and make a grabbing motion with your hands.
Did your hands go through thin air, or did they encounter something soft yet substantial? If the latter is true, we can all breath a sigh of relief—the LHC didn’t destroy life as we know it, and your butt is safe. For now.
The collider was actually turned on on Friday, although the first collisions from its accelerating beams of particles weren’t expected until early December. Much to the scientists’ surprise, collisions were detected as early as Monday. Check again if you need to, Buzzketeers.
If you’re looking for something to worry about, however, you might consider the following: the machine isn’t anywhere near full power yet. The protons involved in Monday’s collisions had been accelerated to the point where they had 450 billion electron volts. In the next few weeks, the LHC team will accelerate the particles up to 1.2 trillion electron volts, and, eventually, the facility should be accelerating protons to 7 trillion electron volts. When you’ve got protons heading each way, that means collisions will involve 14 trillion electron volts.
Yowza, right? I mean, the next most powerful particle accelerator, the Tevatron in Illinois, can only inject 900 billion electron volts into its accelerating particles—the LHC can do more than 15 times that!
But what does that mean? That sounds like a frightening amount of energy, so why doesn’t the Earth rumble and moan like a house in a storm whenever a large particle accelerator is turned on? It is a lot of energy, especially when you’re concentrating it into individual protons, which are, of course, very very small. But an electron volt is a very small unit of energy; it is defined as being “equal to the amount of kinetic energy gained by a single unbound electron when it accelerates through an electrostatic potential difference of one volt.” One trillion (that’s a million millions) electron volts—one fourteenth of the total energy of the LHC’s biggest possible collisions—is approximately equal to “the amount of energy of the motion of a flying mosquito.” That might be a deceptively small analogy—I’m sure it takes much much much more than a few bugs on treadmills to get the LHC powered up, and, again, that’s a lot of energy to be concentrated in a single subatomic particle racing at nearly the speed of light—but it’s an interesting comparison.
Strangelets and micro black wholes: 0; continued existence: 1.
An 11-pound contraption built by LaserMotive of Kent, Wash., successfully climbed up a kilometer high cable suspended from a helicopter in 4 minutes 2 seconds. This qualified them for $900,000. If they had done it in 3 minutes the prize would have been 1.1 million dollars. In four years of the power-beaming competition, LaserMotive is the only competitor to qualify for a cash prize.
Million dollar prizes are motivating research and development in areas that probably wouldn’t be done otherwise, said Andrew Petro, manager of NASA’s Centennial Challenges program. Many of these challenges have just finished.
Winner in Contest Involving Space Elevator New York Times
In addition to other environmental technology add-ons that strip out the fly ash, sulfur dioxide and nitrogen oxides, the Mountaineer Power Plant in West Virginia now also uses a carbon-capture unit built by Alstom. Dubbed the "chilled ammonia" process, baker's ammonia is used to strip carbon dioxide from the cooled flue gas and then, by reheating the resulting ammonium bicarbonate, captures that carbon dioxide, compresses it into a liquid, and
pumps it 2,375 meters straight down into the Rose Run sandstone, a 35-meter-thick layer with a nine-meter-thick band of porous rock suitable for storage. (or...) into Copper Ridge dolomite, which has much thinner strata for possible storage, more than 2,450 meters down. Thick bands of shale and limestone that lie on top ensure that the carbon dioxide does not escape back to the surface. Scientific American
Only about 1.5 percent of the carbon dioxide billowing from its stack is being captured now. Scaling up the process to capture 20% of the CO2 will cost at least $700 million. The removal of carbon dioxide will add abouts 4 cents more to the current cost of Mountaineer electricity (roughly 5 cents per kWh). This chilled-ammonia technology should be available commercially by 2015.
By offering a $10 million dollar prize, the Progressive Insurance Automotive X PRIZE seeks to enable development and stimulate demand for clean, fuel efficient vehicles.
In the Design Judging process, automotive experts evaluated 97 registered entries for:
53 vehicles are moving forward in the competition with 28 represented in the Mainstream Class and 25 represented in the Alternative Class.
43 teams, representing 18 states, 10 countries and 6 fuel types, now advance to the most exciting phase of the competition, performance and safety testing. Vehicles will be tested for efficiency, performance and durability under real-world conditions. Vehicles will race the clock through cities, up hills, and will need both speed and distance capability.
Half of the $10M purse will be awarded to the Mainstream Class winner. The remaining $5M will be split between two winners in the Alternative Class - one vehicle with side-by-side seating, and one vehicle with tandem seating. Performance testing will begin in spring 2010 and winners will be announced in September 2010.
And, let’s face it, who hasn’t had the urge now and then? At the “Quantum to Cosmos” physics conference in Waterloo, Canada, seven physicists were asked, "What keeps you awake at night?" (Apparently, they meant “what issue in science” as opposed to love, money, or lack thereof.) The panel came up with some pretty heavy questions:
Why are the fundamental laws of nature the way that they are? There doesn’t seem to be any reason why they couldn’t be some other way. Are there, perhaps, other universes with other rules?
How does the Observer Effect work? This is a little deep for me, but apparently at the sub-atomic level, simply observing a particle over here can effect another particle thousands of miles away. How does nature do that?
What is the nature of matter, anyway? Especially the “dark matter” which is theorized to exist in outer space, messing up all our gravity calculations.
On a related note, will string theory ever be proven? String theory is the latest theory for how matter and energy interact at the sub-sub-sub-atomic level. And while it is very elegant and seems right on paper, no one has any idea how to conduct an experiment to prove or disprove it.
How do complex systems arise out of simple, basic particles and forces? You know, complex systems. Like life, the universe, and everything.
How did the universe begin, anyway? Physics can only take us back to a few fractions of a second after the Big Bang, a moment at which the universe was very small, very hot, and very dense. Before that, the laws of physics break down. No one knows how to describe the Bang itself, or how / why it happened.
Which brings us to, what are the limits of science? Science is based on observation and experiment. But, at some point, you run into ideas that can’t be tested. In theory, it’s entirely possible that there are other universes. But we’re stuck in this one—how would we ever know?
If anyone has answers to any of these questions, please send them to Canada ASAP. It sounds like there’s a bunch of scientists up there who could use a good night’s sleep.
Como Park will have 3 or 4 circulating shuttle buses next year to help solve the traffic and parking problem at the Como Park Zoo and Conservatory. They will allow free and easy parking by the State Fair grounds and within 7 minutes, will drop you off at the front door.
Ultracapacitor buses have low maintenance cost, low operation cost, zero tailpipe emission, and can reach a zero carbon footprint if powered by renewable energy sources.
The estimated savings in energy costs over the 12 year life of the bus (at current electric and oil prices) is $200,000.
Ultracapacitors will only power a bus for 5-10 blocks, then need about 3 minutes to recharge. Only two recharge stations would be needed, one at the parking lot and one a the conservatory drop off. The bus recharges while passengers load and unload. Capacitors do not wear out like batteries. A capacitor bus is 40 per cent cheaper to build than a battery powered bus. Because the buses can use regenerative braking, they use 40 percent less electricity than an electric trolley using over head wires.
I hope to one day live in a house that produces more energy than it uses. A competition between 20 such houses is going on right now on the Mall in Washington DC. The Solar Decathlon joins 20 college and university teams in a competition to design, build, and operate the most attractive and energy-efficient solar-powered house. Points awarded in ten categories determine the overall winner. As of today (Mon) we have climbed up to 7th place(click for most recent rankings).
I have been excitedly working my way through information as it comes in. You can follow a umn_solar_house Twitter feed and there is an ICON Facebook fan page. The Solar Decathalon landing page allows you to jump to photos, videos, and team websites(not working? Try the site map). The University of Minnesota's ICON landing page branches off into a blog, a virtual tour, and lots of educational pages about design. The media (WCCO News and Washington Post) and bloggers (myself included) will be all over this. I recommend GetEnergySmartNow.com's cheat sheet and their overview of the UMN ICON house. You can also download a 966KB PDF media kit about the Solar Decathlon.