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The Attempt to Put Creationism Back in The Classroom
Hypatia
State governments are grappling with massive budget deficits, overburdened social programs, and mountains of deferred spending. But never mind all that. For some conservative lawmakers, it's the perfect time to legislate the promotion of creationism in the classroom. In the first three months of 2011, nine creationism-related bills have been introduced in seven states—that's more than in any year in recent memory:


http://motherjone...+Marble%29

Holy thit - NM is on the list.

*Going to pack now*
Edited by Hypatia on 03/24/2011 22:47
 
catman
Well, don't come to TX if you want to get away from it!
"If I owned both Hell and Texas, I'd live in Hell and rent out Texas." - General Sheridan
 
Jeebus
I would like to tell them what to do with it.
 
seeker
Think how much easier this makes education. The answer to everything is 'magic'.
"Those who cannot remember the past are condemned to repeat it." - George Santayana
 
Bob of QF
Or the Kristian Translation of "magic": GodDidIt
Quantum Junction: Use both lanes

Reality is that which is left, after you stop believing.
 
JohnH
I like some of the explanations for the need for these laws. They show the intellectual capacity of some of the proposers.

As I was afraid might be the case at least one state is allowing global warming to be questioned. It shows the abilities of true believers. Some phenomenal percent of climate scientists know their is a strong human caused component to climate change, the few that don't get equal billing.
 
catman
I can't say that I know that humans have a lot to do with climate change, but it seems extremely likely, about as likely as that there is no god.

One thing that really bugs me is how 'green' a lot of people think they are because they drive electric cars. Meanwhile, those coal-fired power plants continue spewing pollution and greenhouse gases into the air. Only if the electricity is produced in a nonpolluting way are the electric cars actually 'green'. Coal is worse than petroleum.
"If I owned both Hell and Texas, I'd live in Hell and rent out Texas." - General Sheridan
 
JohnH
catman, the physics are fairly clear and the bulk of climate scientists are in agreement. I think there is a difference between the "philosophical" question if there is a god. It is difficult to present scientific evidence one way or another about god, other than the bible is bs.

And, you are very correct electric cars use power that is often produced by dirty plants. I thought about doing the calculation when I was still an engineer but I found that collecting all the appropriate data was difficult. I will point out that efficiencies as high as 85% are readily obtained with electric motors and can go as high as 95%. The problem is determining what the loses are in providing variable speed control and generation and transmission efficiencies.

Typical gasoline powered engines are around 30+% efficient. These questions are not easily answered.
 
catman
I know the efficiencies of electric motors is higher, but that isn't what I was referring to. (And no, I don't think I'm some sort of "supreme being"!) Smile

You make a good point concerning the poor analogy I made between the likelihood of humans being a major component of climate change and the unlikeliness of a god. I don't see how seven billion people on this planet burning coal to make electricity, destroying the rain forests and driving petroleum-powered vehicles can not have an effect on the atmosphere and thus the climate. As for a god, if there happens to be one, it is supremely unconcerned about us humans.
"If I owned both Hell and Texas, I'd live in Hell and rent out Texas." - General Sheridan
 
seeker
30%? I didn't realize it was that low.
"Those who cannot remember the past are condemned to repeat it." - George Santayana
 
Bob of QF
seeker wrote:

30%? I didn't realize it was that low.


At least-- some are slightly higher, others not so much.

What's interesting? Is a great deal of lost energy goes out the tailpipe, in the form of hot exhaust gasses and unburned fuel.

Think about it: what does a catalytic converter operate on? What is there to catalyze? Unburned fuel.

Engineers have weaned the infernal combustion engine of as much fuel as they can (lean burn engines) but too little, and it simply doesn't work. They are at the ragged limits of what's possible with the tech.

What's sad, to me, is that there are other methods of generating rotary motive impulses, using liquid fuels, than a piston engine. And these other ideas have the potential to be much more efficient.

That being said?

One ought to point out, that even at 95% efficiency of a well-engineered electric motor? The energy losses between the point of origin-- power plants-- and the final product-- that automotive electric-- are worse than a gasoline engine...

... much is lost in the actual creation of the electric current-- generators are not all that efficient at converting rotary motion into power (alas I don't recall the exact figures, but 50% seems about right).

Then resistance in the delivery wires takes it's toll -- ever notice major power-delivery wires never accumulate ice or snow? Too warm... more losses in the transformers, to step it down to consumer voltages.

A >>huge<< loss in the battery's charging methodologies. More loss in the battery itself-- batteries are just not that good at taking the energy put into them, and putting it back out-- 30%? I think or less. Is why they get hot when you charge them, and why they get hot when you discharge'em too. Think: warm cell phone during a long call...

Then another huge loss at the motor-controller.

So what percentage of the initial energy (burning coal, burning oil, falling water) actually makes it to the 95% motor? I have no idea, but I'd wager less than 1%...

Grin

Perspective-- you gotta keep it all in perspective.

Edit: some googling, and it appears some of my figures have been made obsolete by modern batteries and modern motor-controllers. Some sites quote up to 90% efficiency for modern battery chemistries, and as high as 80% on the controllers-- this is much higher than when I last looked.

More, some sites claim that even the modern gasoline engines are down around 20% efficient, which is lower that what I'd discovered-- I suppose it depends on who's doing the measurements?

I did note that most of the sights I found, failed to consider energy losses from the point of origin (powerplants), and only measured raw energy going into the battery, and power coming out at the wheels.

To me, a highly disingenuous oversight.

Pfft
Edited by Bob of QF on 01/18/2012 14:48
Quantum Junction: Use both lanes

Reality is that which is left, after you stop believing.
 
JohnH
Bob of QF, you made an excellent analysis of why I gave up trying to figure out if there was in fact a net energy use benefit to electric cars. So many variables to keep track of and dependent on a bunch of information that is hard to find, a simple one what is the average power loss to a retail customer per kw. Or what is average percentage of renewable electrical power nationwide.

For your and others information for a long time motor controllers relied on resistance to vary speeds. Modern chopper controllers use a sort of pulsing to vary speed and are much more efficient, they were terribly expensive when new but have come down greatly in price.
 
Bob of QF
JohnH wrote:

Bob of QF, you made an excellent analysis of why I gave up trying to figure out if there was in fact a net energy use benefit to electric cars. So many variables to keep track of and dependent on a bunch of information that is hard to find, a simple one what is the average power loss to a retail customer per kw. Or what is average percentage of renewable electrical power nationwide.

For your and others information for a long time motor controllers relied on resistance to vary speeds. Modern chopper controllers use a sort of pulsing to vary speed and are much more efficient, they were terribly expensive when new but have come down greatly in price.


I just wish they'd come down even more-- I had once considered home-brewing up an around-town all electric. Such projects abound on the web.

And purchasing an otherwise sound car with a blown engine is cheap enough to do. I had planned on using a used motor from an electric fork-lift, and getting a manual transmission automobile, putting in a buncha lead-acid deep-discharge batteries here and there (to keep it balanced).

But, when I priced a modern controller? They >>start<< at $2000 and rapidly go higher... this is a basic controller too-- with no reverse (although that's simple enough) and certainly no regenerative braking.

To solve the gearing issue, I had planned on mating the motor directly to the tranny's input shaft, skipping the clutch-- you don't need one-- simply let off power to the motor, it coasts, and shift as you normally would. And a tranny obviates the need for the reverse switchgear too-- simply go into reverse on the tranny. Most projecteers who've done this, comment that 2nd gear is your most used setting, rarely needing the others. Occasionally going to 3rd gear on a long stretch of highway, to conserve battery power a wee bit. And the observation of having the advantage of a mechanical reverse is plain enough. In 1st gear, most of these can also pull up stumps, if you can find the traction...

Smile

Alas, what ended the project was that controller's pricetag-- and finding one used is all but impossible, at least when I looked. End of the line, for now.
Quantum Junction: Use both lanes

Reality is that which is left, after you stop believing.
 
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