Let's burn more sunshine 4

[fast4door]

Climate change deniers, go away.

So let's say global warming is caused by pulling tightly-packed carbon out of the ground in solid/liquid form, then combining it with oxygen and creating more CO2 than there was previously. Let's also say we want to simply freeze the amount of CO2 in the atmosphere and dispense with this "sequestration" baloney. In that scenario, we would need a carbon-neutral course of energy. That leaves nuclear or solar or bio-fuels. I want to talk about bio-fuels.

Here's what I can't figure out. Nature has been capturing sunlight and turning it into carbohydrates and lipids for like a trillion years. There's tons of energy out there. We're really good at disassembling those hydrocarbon chains inside of cylinders, turbines, etc. We should be able get good old nature to make our fuel for us. Is there any hope to the people that want to make biodiesel from algae? Are the yields unrealistically low?

 

[cranky108]

As dumb as this sounds, there are gas turbines that operate at 3600 rpm. So what's the advantage of the higher speed?
What's the exaust tempeture of an otto cycle engine?

If efficency was the important factor, then why aren't we using 2 cycle engines? They should have twice the power output for the same mass.

As far as that goes why did VW get away from the air cooled engines?

The understanding I see is we want a vehicle that is efficent, polution free, and is inexpencive. You can't have all three so it was decided that price will be ignored. The problem with that thinking is, people not being able to afford a newer vehicle, will keep older vehicles alive, which defetes the gains you are hopeing for.

 

[SomptingGuy]

One word cranky: "legs"

- Steve

 

[KENAT]

The M1 Abrams has a gas turbine, and is very thirsty as I understand it. Plus there's the issue of what to do with that nice hot exhaust which for cars is not an insignificant issue.

Cranky, power to weight ratio is not necessarily related to efficiency.

Pat - thankyou.

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[patprimmer]

Air cooled VWs where a tad noisy and despite power to weight potential for the day and stress levels engine life balance, the cost and noise where insurmountable. The similar design is still used in aircraft where noise is not such an issue but power to weight and reliability most certainly are.

Regards
Pat
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[rb1957]

aren't 2-cycle engines inherently less effcicent than 4 stroke engines ?

i think turbines work well with a steady load, and don't respond well to rapid changes in load.

but aren't we headed towards electric/hybrid vehicles ? this at least moves the CO2 question to large scale power plants which i guess are inherently more efficient than millions (or craptillions ?) of smaller sources ? personally i'd be much happy with the AGW debate if we were encouraging developing countries to "leap-frog" the traditional gasolene engines and adopt a more electrical based engines. rather i see we're penalising the developed economies, and giving developing countries free license to do whatever they want. and don't get me started on crabon trading scams ... damnit, i started myself on it ...

 

[patprimmer]

That depends on what you mean by efficiency.

Regards
Pat
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[cranky108]

Well the problem with mass transit, out side major cities, is it cost to much (both to install and maintain). So cars are unlikely to go away in the near future. Buses are unconfortable, and they don't go where I want to go (like near enough to my house). The roads are unsafe for bikeing, because of the bad drivers.

Sounds like a list of excuses, but where is a solution?

Would it not be better to make telacommunting a reality for more people? Why do I need to be physically at so many meetings?