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Comment: Light but reactive element = high energy density (Score 1) 81

by Ungrounded Lightning (#47718377) Attached to: How Argonne National Lab Will Make Electric Cars Cheaper

"lithium is in the upper left-hand corner of the periodic table. Only hydrogen and helium are lighter on an atomic basis."

  I'm wondering if this is a non sequitur for electric batteries.

Not a non sequitur at all.

An important factor for batteries is energy density: How much energy is stored per unit mass. This is particularly important for electric cars: The higher the energy density, the less mass you havce to haul around for a given amount of "fuel", which means the less "fuel" is spent hauling your "fuel" around, so it's a more-than-linear improvement.

Lithium is both extremely light and a very reactive nonmetal. So you're talking about a lot of energy per unit mass for the lithium-based electrode's contribution to the reaction.

Comment: Re:Drop solar heat for direct conversion (Score 1) 442

by Smidge204 (#47711961) Attached to: Solar Plant Sets Birds On Fire As They Fly Overhead

Except you can not exceed the solar power that hits the surface of the planet from the sun.

...which is a hell of a lot of energy. Collectively it's several orders of magnitude more than we as a species could ever reasonably harness, let alone use.

You could, for example, generate more kWh of electricity by putting 15% nominal efficiency PV systems on the roofs of ONLY single-family homes in the US, based on 2010 census data (67% of 130 million residences being single-family homes, with an average size of 2,400 sq.ft.).

In other words, we could hypothetically generate more than 100% of the electricity we need in 7800 square miles - about 5 Rhode Islands. That's at 15% nominal efficiency, assuming only 4 hours per day of operation. In other words, an extremely conservative value.

Just putting things into perspective.
=Smidge=

Comment: Re:Some can be done - and is. Most is bull. (Score 1) 435

by Smidge204 (#47711197) Attached to: Is Storage Necessary For Renewable Energy?

What resources did you use to model these inputs? PVWatts I can understand for solar, but I'm not aware of any similar tools for wind and micro-hydro. Genuinely interested in what your data sources were.

Not that I'm yet convinced your model is applicable to a regional or national scale grid. Did you account for geographical diversity? Availability of these resources spread out over maybe 200-300 mile radius?

Also, peak demand of 5kW for 3 hours? My home has all electric appliances and I rarely, if ever, hit that... including the 3kW clothes dryer. This observation is neither here nor there, but that just strikes me as a high value.

To put things into perspective, I've been collecting minute-by-minute data for my own home's electrical usage (Got one of these things) and based on incomplete-at-the-time data it was looking like I could get away completely off-grid with a 6-7kW PV system and about 6kWH of storage. Less if I was smarter about how and when I used that power. Maybe your data doesn't have good enough resolution to really optimize the system.
=Smidge=

Comment: Re:Estimates (Score 2) 442

by Smidge204 (#47711105) Attached to: Solar Plant Sets Birds On Fire As They Fly Overhead

1. Solar Thermal plants are built in the desert because that's where they have the most ideal operating conditions. The fact that there are more birds in forests than deserts is completely irrelevant because they don't build concentrating solar plants in forests.

2. We would expect the casualties to scale roughly with the number of plants, so is you had 1,000 such plants, that would be 1,000x the casualties. Still a drop in the bucket compared to the billions of birds killed by feral cats every year in North America.

3. You are right, of course, however you have to consider a cost-benefit as well. The cost of preventing bird deaths from not building concentrating solar plants (both monetarily and environmentally) versus, say, the cost of preventing bird deaths by doing something about the cat population. If saving the birds is the priority, then perhaps your dollar would be better spent on programs to reduce feral cat populations than preventing solar thermal plants from being built.

=Smidge=

Comment: Re:12% of the population is Muslim (Score 1) 358

by Ungrounded Lightning (#47698599) Attached to: Ebola Quarantine Center In Liberia Looted

Well, they cannot become martyrs by just dropping dead. At least they have to kill some unbelievers as well...

Actualy, they CAN become martyrs by dropping dead - after deliberately NOT leaving the area of a plague and thus avoiding the spreading it, at the cost of their own lives.

Martyrdom doen't just come from being killed in a religious war.

Another way to become a martyr, for instance, is to die in childbirth.

Yet another is to die while defending your home and/or family from robbers or other attackers (as my wife pointed out to a crook who was trying to extort "taxes" for a local gang.)

Comment: Early reports indicate they may have had reasons. (Score 2) 358

by Ungrounded Lightning (#47698539) Attached to: Ebola Quarantine Center In Liberia Looted

According to a report I saw (following a link from the Drudge Report yesterday):

1)The early symptoms of Ebola are very similar to those of Malaria, to the point that people with malaria are being thrown into the ebola quarantine camps. (Also: Many of the people who HAVE ebola, or their support network, may THINK thay have malaria.)
2) The camp ran out of gloves and other protective gear - leaving the staff and patients unable to clean up after and avoid contagin from the body fluid spillages of the actual ebola patients. Come in with SUSPECTED ebola and you soon have ebola for sure.

That, alone, would make it rational for someone not yet sick or mildly sick, incarcerated in the camp, to break out and hide out.

3) Stories are circulating in the area that ebola is a myth and the oppressive government factions/first worlders/take your pick of enemies are using this story, plus the odd malaria case here and there, to create death camps and commit genocide in a way that gives them plausible deniability.

That idea, of course, can lead to mass action by some of the local population to "rescue" their fellows and sabotage the camps.

The whole think is a real-world example of the cautionary tale "The Boy who Cried 'Wolf'". When the officials lie to the people for their own benefit, repeatedly, until the people come to expect it, the people won't believe them when they are telling the truth about a real threat - and all suffer.

Comment: Re:Truly sad (Score 1) 358

by Ungrounded Lightning (#47698411) Attached to: Ebola Quarantine Center In Liberia Looted

Ebola is one mutation away from being airborne transmissable. It already happened with Ebola Reston -- fortunately for us all, that turned out to be transmissable to monkeys but not humans.

I've heard reports that it may have happened with this one, too.

It doesn't have to be as GOOD at doing airborne transmission as, say, the common cold, to be a BIG problem.

Comment: Re:Some can be done - and is. Most is bull. (Score 1) 435

by Smidge204 (#47696889) Attached to: Is Storage Necessary For Renewable Energy?

A single home isn't a very good proxy for a regional or even national scale grid.

With your house example, the only options are solar and generator. In reality you would have more than these two options. For example, add wind to the mix. You can argue that it's not 100% but it will cover a lot of run time at night, saving you battery capacity and reducing the required over-sizing of your PV system. Perhaps instead of 400% oversizing on PV, you only need 200% PV+Wind oversize.

Now add in something else... biogas perhaps. That covers you a little bit more and you can again reduce your oversizing.

Now add geothermal, hydro, solar-thermal (which works at night), and you start to easily fill in the gaps.

The US had 1,153 billion watts of generating capacity as of 2011 (Nameplate ratings, spreadsheet) and used ~3,797 billion kilowatthours that year. Naively we can say that if all our powerplants ran at 100% nameplate capacity, we could generate an entire year's worth of electrical energy in just about 3300 hours, or about 4 months... giving us a roughly 300% oversize on our electrical generating capacity *now*.

The key, of course, is that none of those plants are operating 24/7/365, and rarely are any of them operating at peak capacity.
=Smidge=

Comment: Re:There is a big construction boom in Germany... (Score 1) 435

by Smidge204 (#47696309) Attached to: Is Storage Necessary For Renewable Energy?

I'd also point out that Germany's accelerated decommissioning of nuclear power plants (all shutdown in 8 years) has a lot more to do with the coal plants than the increase in renewables.

Doesn't make sense: Coal power has actually decreased since 2000 when it was first decided that Germany should ween themselves off of Nuclear power, and the slight increase in coal power in the past two years is only a fraction of retired nuclear capacity, both in total and as a percent of total generation.

Germany's renewable energy push is what's filling that gap. If it wasn't for the nuclear phase-out, they'd probably have lost a third of their coal plants instead.
=Smidge=

Take care of the luxuries and the necessities will take care of themselves. -- Lazarus Long

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