Global warming

[DonPMitchell]

In the USA, many evengelicals believe these are the End Times, and so there is no need to worry about the environment.  Although not religious myself, I prefer jdbenner's point of view.

I care about the environment and climate issues, I am just very cynical about all political mass movements.

Just wait until the Earth's magnetic field starts to reverse, which may happen in the next few centuries.  I've already heard a lot of crap about this, from the likes of Neil deGrasse Tyson, claiming the Earth will be scorched by space radiation if this happens.  Do real scientists ever appear on TV?

[Satanic Mechanic]

Do real scientists ever appear on TV?

Nope, unless they look like Baywatch babes.

SM

[jdbenner]

I care about the environment and climate issues, I am just very cynical about all political mass movements.

I am also troubled by the way politicians and the media portray environmental issues.  Usually junk science or a Panetheism to defend there position.

As for the science they rarely concider all effects of their plans.  What about the pollution inherent in processing pressis metals, for as fuel cell catalysts?  Or, is solar cell construction non polluting.  What about battery disposal? Why all the hype about Hydrogen?  Hidreg en must first be separated from outher molecules, water methane etc, in an endothermic reaction. And storage issues are a defiant disadvantage.

The Panetheism is expressed by the attitude that puts plants and animals ahead of people.  Are we as humans a disease, as I have herd some state?  Or are we the gardeners, maintaining order?

[Satanic Mechanic]

As for the science they rarely concider all effects of their plans.  What about the pollution inherent in processing persis metals, for as fuel cell catalysts?  Or, is solar cell construction non polluting.  What about battery disposal? Why all the hype about Hydrogen?  Hidreg en must first be separated from outher molecules, water methane etc, in an endothermic reaction. And storage issues are a defiant disadvantage.

I can answer some of your questions: 
-Growing photovoltaics generates a lot of arsenic waste and it cannot be reclaimed.
-The U.S has been recycling batteries since 1972.  98% of the battery is recycled.
-Hydrogen was a "technology fad" to the media for the last eight years.  Same problems with hydrogen still exist; generation, containment/storage and cost.

SM

[Johno]

True, although Hydrogen does have a couple of REAL advantages if we can overcome those disadvantages.  To wit:

* Efficency of use.  As an energy transfer medium from electrical energy to vehicle energy it has the potential to be very useful. A fuel cell currently has 60% efficiency or greater, and that would have to be one of the best ways to get electricity from generation site to vehicle.

* I can't think of much apart from petroleum that could be used to create jet fuel (although I am happy to stand corrected if someone knows an alcohol based alternative).  LH₂ is about the only realistic option, and even then it will take a lot of time and money to perfect.

[DonPMitchell]

Given time, I think market forces can solve these problems.  Academic scientists futz around with hard problems for decades.  But when someone focuses professional engineers on a specific probelm, it gets solves pretty fast.  I am hoping that energy prices will propel the issue (e.g., "we can make money from solar power now").  Markets have a harder time reacting to negative reinforcement (e.g., "global warming is bad for business").

Solar power seems like the best long-term energy source.  1400 watts/meter of free energy is nothing to sneeze at.  It just is expensive to convert and store it now.

Fuels with carbon would be fine if they are made from CO2 in the atmosphere, instead of new carbon.  And ultimately, petroleum may be more important for plastics and chemicals than as something to just burn.

This leads me to think that bio-fuels are a good idea, but not the ones currently proposed.  Ethanol from corn is a farm-subsidy boondoggle that doesn't work.  Where you would make a fortune is by breeding or maniuplating crops to produce energy in a better form.  Or, develop a way to utilize the whole corn plant, and not just the little bit of starch in the seeds.  Corn is actually very efficient, it can grow six inches a day, but most of the biofuel in it is cellulose, which is hard to chemically break down.

[Johno]

Bearing in mind I can see what you mean about ethanol, I did want to ask a question of someone with more of a clue on this than me:

Okay, we grow a plant for ethanol (in Australia, it will most likely be sugar cane).  It is made largely of Carbon from the atmosphere, correct?

So: Production of ethanol already involves a carbon sink.  Now, we extract sugar to ferment for ethanol.  This process releases some of that carbon.  Once the fuel is burned, a little more of said carbon is released.  The remainder of the carbon is released as the waste rots.  So all the carbon is returned to the environment. 

Yet the carbon was extracted from the atmosphere anyhow. This would seem to therefore mean that this fuel is carbon neutral - correct?

(Leaving aside the fact that it is also being used as an excuse to pay inefficient farmers yet another subsidy, but I digress).

[cartmancakes]

We need to learn how to recycle better.  For example...

I live in Phoenix, AZ.  Nasty summers, lots of energy used in air conditioners.  Quite necessary, really.  My father-in-law came up with a solution that he is currently implementing.  He decided to use a small wind-mill against his A/C unit.  It blows at 27MPH, and the wind-mill just needs 25MPH to generate a decent current.  Turns out, the exhaust air from his A/C will end up powering about half of the needed electricity for his A/C. 

I thought that was brilliant.

[jdbenner]

He decided to use a small wind-mill against his A/C unit.  It blows at 27MPH, and the wind-mill just needs 25MPH to generate a decent current.  Turns out, the exhaust air from his A/C will end up powering about half of the needed electricity for his A/C.

If the energy in the air current was suplied by a fan, and the air current powers the wind mill, then the fan motor powers the wind mill.  The windmill slows down the air (the kinetic energy in the air is extracted).  So eather the fan will have to work harder to push the air through the heat exchanger, or the fan was over powered to begin with.

This scheme smacks of perpetual motion.

No Offence to your Father in Law

[jdbenner]

Bearing in mind I can see what you mean about ethanol, I did want to ask a question of someone with more of a clue on this than me:

Okay, we grow a plant for ethanol (in Australia, it will most likely be sugar cane). It is made largely of Carbon from the atmosphere, correct?

Correct.

This would seem to therefore mean that this fuel is carbon neutral - correct?

Also correct.

If you want to learn more about relative efficiencies of various Bio fuels check out this Science News Article.
http://www.sciencenews.org/articles/20060715/fob4.asp