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Comment Re:It is all about baseload (Score 1) 488

Water pumping is slow. Hydrogen is fast, esp when it is being used dynamically at the receiving end. I would suggest that hydrogen does not need to be stored at the receiver the way water is currently for potential energy. And it is potential energy that we are talking about. The problem becomes a much more dynamic one.

Comment Re:It is all about baseload (Score 1) 488

rethink your costs. you do not need to store water and pump it uphill. You store hydrogen close to the coast where it is made, and pump it uphill at much lower cost than pumping water, to the existing power stations and their existing power distribution grid feed points. Then use fuel cells/gas turbines to generate, 24 hours per day. Countries like Denmark with low sunlight flux can import bulk hydrogen from countries closer to equator with low cloud cover fraction.

Submission + - Houston, we may have a problem, or O'Brien's Law 1

ipsender writes: It is written that O’Brien observed Murphy to be an optimist. While NASA labours over the next manned mission to Mars, it is worth considering, as an interested public, the scale of what NASA’s engineers are trying to achieve.
All previous attempts to send missions to Mars have been unmanned. Of the 40+ missions since 1960, about 40% could be deemed a success. Transporting humans to Mars obviously will add to the complexity. Everything about a Mars mission is more difficult: the time in space required, at least 24 months, means longer exposure to radiation for humans and hardware, longer opportunity for hardware parts to fail, larger amounts of stores including fuel and gases to carry, and the similar risks faced by the Apollo mission for landing on the planetary surface and subsequent take-off. Add to these the time and distance factors, making rescue missions extremely unlikely to be effective. Of the previous handful of Apollo expeditions carrying humans, one (Apollo 13) almost ended in disaster when an incorrectly-engineered part failed, and was saved only by ingenuity and persistence by ground and flight teams, and the integrity of the surviving systems. Even on the ISS, the excellent science and engineering invested in the manufacture of components does not prevent the failure of water recycling systems, ammonia pumps, solar panel bearings, spacesuit water containment systems, main bus switches, torn solar panels, and computers. Then there is the unlikely but ever-present risk of collision with high-relative velocity objects in space. Astronauts, some of the best and brightest, most committed, highly-trained, and adaptable folk, are ready for risk. But what of the ethics of sending people on such a risky mission? Has enough been achieved to significantly reduce that risk? I would argue not. Scientists and engineers approach difficult problems with good design, excellent materials and manufacture, testing and retesting, especially of integration of systems. Then they may add redundant systems, or backup. But to date, a single craft is planned for the mission. It works or it does not. Would it make more sense to send a small flight of craft, at least three, with interchangeable spare parts, crew exchange ability and redundant stores? With more than one landing craft for rescue of a surface crew if necessary, and each craft able to support the entire crew for a return journey to Earth, a super-redundancy can be achieved. The development costs for three craft are the same as for one craft, so that the extra costs are only for crew training, manufacture and launch (probably more processes are accountable). After all, Chris Columbus crossed the Atlantic and returned using three ships. What do Slashdotters think?

Submission + - NASA News Briefing on Mars Orbiter Science (nasa.gov)

ipsender writes: NASA will host a news briefing on Thursday, Aug. 4, at 11 a.m. PDT (2 p.m. EDT) about a significant new Mars science finding. The briefing will be held at NASA Headquarters in Washington.

The new finding is based on observations from NASA's Mars Reconnaissance Orbiter, which has been orbiting the Red Planet since 2006. Mars Reconnaissance Orbiter is managed by NASA's Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, Calif., for NASA's Science Mission Directorate in Washington.

Social Networks

Mafia Wars CEO Brags About Scamming Users 251

jamie writes with a follow-up to our recent discussion of social gaming scams: "Mark Pincus, CEO of the company that brought us Mafia Wars, says: 'I did every horrible thing in the book just to get revenues right away. I mean, we gave our users poker chips if they downloaded this Zwinky toolbar, which was like, I don't know... I downloaded it once and couldn't get rid of it.'" TechCrunch also ran a interesting tell-all from the CEO of a company specializing in Facebook advertisements, who provided some details on similarly shady operations at the popular social networking site.

Comment Vale, JG B (Score 1) 162

Indeed sadness comes with the passing of a courageous writer. Courageous because he attempted the difficult feat of overtly connecting the strange erotic and violent internal world of unconcious (and not so unconscious) fantasy with patterns in and products of human civilisation. His more surreal and difficult work sometimes proposed that the human condition, if not genetics, were somehow pre-ordinately composed with information which could be expressed biologically, in not always adaptive ways, to socially or environmentally bizarre changes and crises. His melding of the more basic human urges with technological sophistication drew a range of extreme responses amongst avid readers and critics, which perhaps suppressed a wider appreciation of some of his predictive ability and linguistic adeptness. It could be argued that a proportion of his surreal writing was a product of the horrors he witnessed in concentration camps as a child, but if so, he took a long time to tell his story in direct terms - in 'The Empire of the Sun'. But even if so, we have been enriched by his foretelling of perspectives on humanity in allegory which few others have attempted. Vale, to a generous story-teller.

Comment Re:17 cents/kwh and it MIGHT get down to 10? (Score 1) 325

"Edison's Pearl River Power Station started up its generator on September 4, 1882, in New York City. About 85 customers in lower Manhattan received enough power to light 5,000 lamps. His customers paid a lot for their electricity. In today's dollars, the electricity cost $5 per kilowatt-hour!"

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