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Comment Re:Amusing (Score 1) 306

In the context of electric vehicles, the big benefit here is the huge reduction in energy needed to thermally manage the batteries, which would decrease the range loss associated with cold and hot weather.

As it is now, lithium ion batteries need to be in a pretty narrow temperature window to perform adequately and not degrade too quickly.

Comment Re:Why (Score 4, Informative) 201

Batteries can store and discharge about 6-10 times the energy required to create them in their lifetimes.

That number seems very low. Got a source?

I was wondering too and did some searching. It looks like the number is realistic. What I found...

I hope I didn't screw up the math. If I did, please ridicule me and mod me down....

Modern EV batteries which are temperature controlled and charge limited have, so far, shown extremely low degradation over 100,000K EV miles.

The owner of this Volt, who is a member of a Facebook Volt owner group claims to still get the EPA rated 35 miles per charge from his Volt after 120K EV miles...

http://www.voltstats.net/Stats...

I personally own a Volt with 32K EV miles and still get the same EV range...

http://www.voltstats.net/Stats...

One charge in a Gen1 Volt is about 10.5 kWh. This means that over 100K EV miles, a Volt battery stores in the neighborhood of 29 MWh of energy.

1/10 of that would by 2.9 MWh

A quick search shows 828MJ per kWh of capacity to produce a lithium ion battery pack. This equates to 3.68 MWh to produce a 16kwh Chevy Volt battery pack.

https://www.quora.com/How-much...

Given that those Volt battery packs have shown little to no degradation so far, it's safe to say they have quite a bit more useful life to go, so they will probably make it close to 36 MWh of lifetime storage, but they will eventually succumb to the laws of physics though and start to degrade.

Comment Re:Make the colleges pay for low value educations (Score 1) 537

Value to the economy is not necessarily value to society.

However, that doesn't seem to be happening, and besides, there's no measurable way to claim that these individuals DO contribute their potential to society in any greater amount than those who are not similarly educated.

Of course there is. You could analyze societal data (like crime rates, school quality and performance, voter participation, healthcare outcomes, etc) among populations with varying education levels and fields.

Comment Re:It's a bit like when Reagan took office (Score 1, Interesting) 432

It was as if the hostage takers are all frightened of what Reagan would do

To the contrary, they knew exactly what Reagan would do. They made a back room deal with Iran during the election - an act of Treason by the gipper.

Reagan should have died of his dementia in federal prison.

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