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Comment You can already get paid for reducing usage. (Score 1) 82

When there is a surge in power usage, power companies have to spool up a fast-acting power plant to keep up with demand. Power companies don't like doing that because the power they produce is pretty expensive, and also tends to be entire fossil fuel fuelled. There is already a scheme in New York and California where you can voluntarily reduce your usage during surge periods called 'OhmConnect' ( https://www.ohmconnect.com/how...). You can actually get paid for not using power during these periods, and if you have a smart thermostat you can set it to turn off AC automatically (or just alter the temperature thresholds) during those periods to get paid by the power company.

Now, if you happen to have a large-capacity battery in the car connected to your house, you could have it set up so that during surge periods it uses energy from your car, and then charges it up afterwards. You get those sweet power company bucks without having to actually change your power usage behaviour at all.

Comment Re: These will be (Score 1) 77

This was seen at 5000' 15 miles east of LAX, which puts it firmly in the LAX Bravo, which is illegal for Part 103 aircraft without prior authorization. Furthermore, part 103 aircraft are not permitted to fly over congested areas, irrespective of airspace.

http://www.usppa.org/federal-a...

However, as long as the jetpack weighs less than 254lbs, has less than 5 gallons of fuel, does not do more than 55kts in level flight, and has a stall speed of 24kts or less, then there are lots of other places you can legally fly it.

Comment Re:7000Wh/kg for graphite foam (Score 1) 298

It's not 7000Wh/kg, it's 7000W/kg.

(See also https://www.graphene-info.com/...)

That means you can get a lot more power from a given weight of aluminum ion battery than you can from lithium ion, but the energy density at 160Wh/Kg is not as good as for instance Tesla batteries, at ~260Wh/Kg.

It's a shame - I got excited for a moment because a 3x energy density for batteries could entirely revolutionize general aviation.

Submission + - Tatooine was likely orbiting in the same plane as its twin suns

The Bad Astronomer writes: A new study by astronomers of binary stars shows that exoplanets orbiting them (circumbinary planets) will orbit in the same plane as the stars if the two stars are relatively close together. If the stars are farther apart, the planets may have a perpendicular (polar) orbit around them. This study looked at the protoplanetary disks of dust and gas around binaries to draw this conclusion. Extrapolating to fiction, this means Tatooine in Star Wars was coplanar with its host stars.

Submission + - Remember that 70-solar-mass black hole announced last week? Yeah, not so much.

The Bad Astronomer writes: Last week, scientists announced the discovery of a stellar-mass black hole with 70 times the Sun's mass, far heftier than theory predicts they can get. Within days, though, four separate papers have come out casting extreme doubt on the claim. They show that the data weren't processed correctly, and that the black hole is closer to Earth than first assumed, which changes the calculations and makes it a more normal 5 — 20 solar mass object.

Submission + - Nearby star is Sun's long-lost sibling

The Bad Astronomer writes: A nearby star, HD 186302, was almost certainly born from the same cloud of gas the Sun was 4.6 billion years ago. Astronomers have found it has an almost identical chemical composition as the Sun, is on a similar orbit around the Milky Way, and has the same age (within uncertainties). Interestingly, it's only 184 light years away, implying statistically many more such stars are waiting to be discovered.

Submission + - Gamma Cephei Ab: The *actual* first discovered exoplanet

The Bad Astronomer writes: The history of the first truly discovered exoplanet is a mess. The first pulsar planet was found in 1992 (after the retraction of a discovery the previous year), and the first one around a Sun-like star in 1995. There was even evidence of one in a spectrum taken in 1917! But the first one actually found is Gamma Cephei Ab, in 1988. Incredibly, that claim itself was retracted in 2002... but then shown again to be real in 2003.

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