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NASA Cancels "Sunjammer" Solar Sail Demonstration Mission

calidoscope Sunjammer was the orignal title (69 comments)

I remember one of my brother's first issues (Apr? 1964) of Boy's Life having "Sunjammer" as the cover story. AC Clarke later expanded the story under the name "Wind from the Sun". FWIW, Boy's Life is one of the magazines digitized by Google Books and you can look up the issue in question.

yesterday
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Wind Power Is Cheaper Than Coal, Leaked Report Shows

calidoscope Re:Article ignores variability (608 comments)

Actually, you're the one who comes across as being ignorant.

Baseload generation is generation is considered to be the lowest incremental cost dispatchable power source. No form of generation has 100% up time, but a well run plant will have very little unscheduled down time. The variability of wind is a huge problem when wind generation becomes a significant portion of total generation at a give moment, requiring a large amount of spinning reserve to keep the grid stable.

FWIW, the limiting factor in power output of an AC generator is not conductor heating, rather it is the amount of power that can be generated without the generator pulling out of synchronism, especially under fault conditions.

about a week ago
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Ask Slashdot: Best Books On the Life and Work of Nikola Tesla?

calidoscope Re:Edison invented the electric light? (140 comments)

What Edison invented was an incandescent light with a high enough resistance to make it possible to powered by a central station, along with the central station, a means of metering current, etc. Edison's work was mostly independent of Swan's.

about a week ago
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Ask Slashdot: Best Books On the Life and Work of Nikola Tesla?

calidoscope The Power Makers by Maury Klein (140 comments)

While this book is not a Tesla biography, it does give a good picture of how Tesla fit in with the beginnings of the electric power industry. The book does give Tesla proper credit for the invention of poly-phase AC and the induction motor, but also points out that Stanley and Thomson were working on AC distribution before Tesla along with a lot of refinement on the induction motor being done by Benjamin Lamme.

It is the likes of Lamme and Steinmetz that are the unsung heroes of the electrical age.

about a week ago
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Data Archiving Standards Need To Be Future-Proofed

calidoscope FITS standard (113 comments)

When the Vatican decided to digitize their archives, they chose to store the mages in FITS format for pretty much the same reasons. One thing FITS doesn't address is preventing unauthorized access to the data.

about a month ago
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3 Recent Flights Make Unscheduled Landings, After Disputes Over Knee Room

calidoscope Re:Today's business class is the 70s' economy clas (819 comments)

In 1972, SAN to OAK was $24.50 on PSA with no restrictions. Equivalent fare on Southwest is ~$260, cheaper fares are available but come with restrictions.

about a month and a half ago
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3 Recent Flights Make Unscheduled Landings, After Disputes Over Knee Room

calidoscope Re:cram lots of people in a confined space (819 comments)

Hmmm, "Get them out by Friday".

A bit OT, but I was surprised to learn that "Attack of the Giant Hogweed" was mostly based on fact.

about a month and a half ago
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Hitachi Developing Reactor That Burns Nuclear Waste

calidoscope Re:Good (200 comments)

Electorate, schmectorate, decisions like this are based on who provides the most campaign donations.

about a month and a half ago
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Hitachi Developing Reactor That Burns Nuclear Waste

calidoscope Re:Good (200 comments)

The proposed reactor design sounds a bit like the EBR-II at INEL, formerly the National reactor test site, with the design also referred to as the Integral Fast Reactor. This program got shut down in the 1990's, though stories have been told about people who were sent out to Idaho to shut it down came back as converts to the cause.

about a month and a half ago
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Power Grids: The Huge Battery Market You Never Knew Existed

calidoscope Re:Yes, we know that. (245 comments)

With solar power, you get peak power and peak air conditioning load around the same time.

Not quite. Peak demand in California is between 6 to 7PM, peak solar production is approximately 12 noon. Peak load does not drop signficantly until well after sunset.

about a month and a half ago
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San Onofre Nuclear Power Plant Dismantling Will Cost $4.4 Billion, Take 20 Years

calidoscope Not surprising (343 comments)

Decommissioning costs are still a lot less than it would cost to build the plant now. Letting the plant cool down for a few years makes the process simpler and safer, though the reactor vessel is going to be a challenge.

about 3 months ago
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Perlan II Project Aims To Fly a Glider To the Edge of Space

calidoscope Re: 100km (44 comments)

Something on the order of 97% of the atmosphere's mass is below 90,000'. 100km is an arbitrary value for the start of space, as the air at 100km is too thick to orbit and too thin to fly in (except dynamic soaring?). In imperial units, 100,000' seems to be the upper limit for flying and 100 miles is about the lower limit for orbiting.

The Perlan II sounds like it will handle like an unpowered U2 - where the planes ceiling will be defined by the "coffin corner" were the low speed stall (classic stall) approaches the high speed stall (Mach tuck from transonic airflow). Perhaps they will be using a more refined airfoil than the U2 to increase the Mach number for high speed stall.

IIRC, the pre-Perlan I sailplane altitude record of approx 47,000 feet was set sometime in the 1960's, surprising it took that long for someone to break that.

about 3 months ago
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The Truth About Solar Storms

calidoscope Re:The failure mode is transformer core saturation (91 comments)

I first heard about use of series capacitors in an electric power systems class, 1H 1975, so they have been around for quite a while. It would seem to me that the caps should be able to withstand the DC potential set up by a Carrington event.

about 3 months ago
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The Truth About Solar Storms

calidoscope Re:The failure mode is transformer core saturation (91 comments)

Any component for a high voltage transmission line is going to be gigantic. Google term "power transmission line series capacitors" should get you started.

about 3 months ago
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The Truth About Solar Storms

calidoscope Re:The failure mode is transformer core saturation (91 comments)

An alternative way of minimizing the effects of a severe solar storm on the grid would be placing series capacitors on the long AC transmission lines. This is done already to increase power transfer capacity of some lines.

Since the solar flare is visible many hours before CME hits, the utilities should have time to configure the grid for the storm. The oerative word here is "should".

about 3 months ago
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One Trillion Bq Released By Nuclear Debris Removal At Fukushima So Far

calidoscope Re:Is that a lot? (190 comments)

Not that much. A typical Tc99m scan involves injection a bit over a billion (10E9) bq per person, albeit half life is only 6 hours. Reminds me of a "warning sticker" for a CB radio - "Danger 5,000 milliwatts".

about 3 months ago
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Rocket Scientist Designs "Flare" Pot That Cooks Food 40% Faster

calidoscope Re:Wow. (204 comments)

I agree wholeheartedly that the pot is more similar to the Jetboil in principle than different. There is a difference in details in that the Jetboil is designed for lighter weight and better heat transfer efficiency than the pot at the expense of a more fragile design.

about 3 months ago
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Today In Year-based Computer Errors: Draft Notices Sent To Men Born In the 1800s

calidoscope Re:dmv (205 comments)

I don't there is anyone in the US who was born in 1897 or earlier.

about 3 months ago
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New Chemical Process Could Make Ammonia a Practical Car Fuel

calidoscope Mid 1960's Army research (380 comments)

There was an article or two in the likes of Mechanix Illustrated or related magazine about the US Army experimenting with ammonia fueled engines. Reports indiacted that engines would function, but had not been developed to the point of practicality. Shudder to think what kind of NOx levels are present in the exhaust.

about 4 months ago
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Scientists Measure Magnetic Interaction Between Two Bound Electrons

calidoscope Newton's ???? inverse cube law (26 comments)

I remember Newton's inverse square law, but magnetic dipoles were more than two centuries after his time.

about 4 months ago

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