Here’s your infographic of the day, courtesy of Hipmunk: visual street signs to work as a helpful tool for pedestrians in various cities. The call out about DC is above, and the full guide (for those of you visiting other cities) is in the post.
Fair
The availability of wind power for renewable energy extraction is ultimately limited by how much kinetic energy is generated by natural processes within the Earth system and by fundamental limits of how much of the wind power can be extracted. Here we use these considerations to provide a maximum estimate of wind power availability over land. We use several different methods. First, we outline the processes associated with wind power generation and extraction with a simple power transfer hierarchy based on the assumption that available wind power will not geographically vary with increased extraction for an estimate of 68 TW. Second, we set up a simple momentum balance model to estimate maximum extractability which we then apply to reanalysis climate data, yielding an estimate of 21 TW. Third, we perform general circulation model simulations in which we extract different amounts of momentum from the atmospheric boundary layer to obtain a maximum estimate of how much power can be extracted, yielding 18–34 TW. These three methods consistently yield maximum estimates in the range of 18–68 TW and are notably less than recent estimates that claim abundant wind power availability. Furthermore, we show with the general circulation model simulations that some climatic effects at maximum wind power extraction are similar in magnitude to those associated with a doubling of atmospheric CO2. We conclude that in order to understand fundamental limits to renewable energy resources, as well as the impacts of their utilization, it is imperative to use a “top-down” thermodynamic Earth system perspective, rather than the more common “bottom-up” engineering approach.
17 Terawatts of electrical wind power would be 50-95% of the maximum land based wind possible with significant climate effects. There would be temperature and rain differences.
Of the 47 TW of energy that we use, about 17 TW comes from burning fossil fuels. So to replace this, we would need to build enough sustainable energy installations to generate at least 17 TW. And because no technology can ever be perfectly efficient, some of the free energy harnessed by wind and wave generators will be lost as heat. So by setting up wind and wave farms, we convert part of the sun’s useful energy into unusable heat.
“Large-scale exploitation of wind energy will inevitably leave an imprint in the atmosphere,” says Kleidon. “Because we use so much free energy, and more every year, we’ll deplete the reservoir of energy.” He says this would probably show up first in wind farms themselves, where the gains expected from massive facilities just won’t pan out as the energy of the Earth system is depleted.
Using a model of global circulation, Kleidon found that the amount of energy which we can expect to harness from the wind is reduced by a factor of 100 if you take into account the depletion of free energy by wind farms. It remains theoretically possible to extract up to 70 TW globally, but doing so would have serious consequences.
Photosynthesis also generates free energy, but without producing waste heat. Increasing the fraction of the Earth covered by light-harvesting vegetation – for example, through projects aimed at “greening the deserts” – would mean more free energy would get stored. Photovoltaic solar cells can also increase the amount of free energy gathered from incoming radiation, though there are still major obstacles to doing this sustainably
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While red food dye may still be a problem in young humans, for roundworms a commonly used lab dye remarkably increases their longevity. Basic Yellow 1, aka Thioflavin T is used in laboratories around the world. Apparently, for the commonly experimented on C. elegens, it provides a substantial lifespan boost. Healthy nematodes treated with the dye lived 50% longer, and those bread to have symptoms mimicking Alzheimer’s showed slowed disease progress. More
The Antikythera mechanism, one of the world’s oldest known gadgets, has coughed up another secret. In addition to tracking time and upcoming Olympic games, the mechanism was also great at tracking the motion of the Sun across the sky. More
This is one of those cool “so-thats-how-it-works” projects that is an easy weekend activity to teach yourself (or your kids) the basics of how a battery operates. More
It could get harder to indulge in a double cheeseburger and fries without feeling guilty.
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FDA proposes calorie counts on menus
It’s about time the ViewMaster got an upgrade. What’s that? It’s not a ViewMaster? Well, you could have fooled us, but either way, the thing’s finally going on sale exclusively at Target April 3rd, and everywhere else starting in June. As you might have already heard, Hasbro’s intro into the crowded 3D arena, simply titled My3D, does take a card from the old ViewMaster deck, but instead of enlisting cardboard discs, this thing uses your iPhone or iPod touch to bring you 3D entertainment. If your kid’s not already hooked on 3D, the $35 viewer could be a decent starter — then again, for $35 you could take yourself out to a nice lunch, give the rug rat a cardboard box, and call it a day. Full PR after the break.
Continue reading Hasbro’s My3D to turn iPhones into glorified ViewMasters starting Sunday
Hasbro’s My3D to turn iPhones into glorified ViewMasters starting Sunday originally appeared on Engadget on Sat, 02 Apr 2011 04:39:00 EDT. Please see our terms for use of feeds.
It’s not that you need a hardware-based H.264 live streaming encoder hanging around in your fifth pocket, but if you’re looking to capture more of life’s moments, why not? Scheduled for a proper introduction at NAB Show 2011, the Minicaster is capable of encoding and delivering a number of streams while also recording at the same time, and those settings can be tweaked directly on the unit itself. The company recommends using it with Wowza Media Server, and if you’re looking to become the world’s next Ustream star, investing in one of these may not be such a bad idea. Emphasis on may, given that the asking price is eluding us at the moment.
Continue reading Minicaster: the pocket-sized hardware-based H.264 live streaming encoder
Minicaster: the pocket-sized hardware-based H.264 live streaming encoder originally appeared on Engadget on Sat, 02 Apr 2011 02:27:00 EDT. Please see our terms for use of feeds.
As you may be aware, Amazon does actually already make it easier for you to shop at places other than Amazon.com with its Amazon Payments service, and it now looks like it might even be thinking about expanding things to brick and mortar stores as well. More specifically, Bloomberg is reporting that Amazon is exploring a mobile payment service based on NFC technology, which would let you pay for items and receive things like loyalty points using nothing other than an NFC-equipped cellphone. Not surprisingly, Amazon is also said to be considering some other features that would send folks back to Amazon.com — Bloomberg gives the example of someone shopping for jeans in a retail store who can’t find the right size, and says that they could simply scan the jean’s tag to order a pair online. Details are otherwise a bit light, and the service is apparently still not quite a sure thing, although a person familiar with the matter says Amazon will decide whether to go forward with it or not “in the next three to five months.”
Amazon said to be considering NFC-based mobile payment service originally appeared on Engadget on Fri, 01 Apr 2011 20:03:00 EDT. Please see our terms for use of feeds.
Gadgets come in all shapes and sizes, but it’s safe to say this is a big’un. Sure, it isn’t exactly portable in the traditional sense, and no 24 month contract is going to make it fit into our budget, but that doesn’t mean it can’t have a place in your life. It’s the Roadster Sport, the latest addition to the Tesla family and released to the world last summer. Version 2.5 is the fastest yet on the road, leaping from zero to 60 in 3.7 seconds yet still getting a rated 245 miles of range.
Of course, we all know that rated range doesn’t necessarily equate to real-world range, and real-world car performance doesn’t always live up to what you read in the magazines, either. Indeed in our testing we weren’t able to make it the full 245 miles that Tesla says you can in a roadster, nor did we come close to approaching this thing’s 125mph top speed. But, after spending plenty of hours wedged inside the cockpit of this $128,500 sporty EV we did walk away mighty impressed, not only with how it drove but in how it sounded. Read on, and you might just be too.
Gallery: Tesla Roadster 2.5 Sport
Continue reading Tesla Roadster 2.5 Sport review
Tesla Roadster 2.5 Sport review originally appeared on Engadget on Fri, 01 Apr 2011 16:30:00 EDT. Please see our terms for use of feeds.
