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Let's burn more sunshine 4

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fast4door

fast4door

Mechanical
May 29, 2012
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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?
 
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TomDot said:
Cheap CFLs do suck. Decent CFLs come on quickly and have good color. They also have a very tiny amount of mercury (under 2 micrograms)

Early and current CHEAP CFLs do have the problems described above. Get decent bulbs (and I'm still talking less than $2/bulb at Costco or something) - and these are all solved issues.
Click to expand...

Exactly. For some reason with CFLs, people mysteriously forget that cost usually correlates pretty well to quality. They buy the cheapest brand of CFL they see, then when it doesn't work well criticize the entire technology, instead of just that brand.

Pay the extra 50 cents for a quality brand, you will get a quality product.

And if your electricity comes from coal, it will result in far less mercury going into the environment.
 
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KENAT said:
Pastoral farming could be massively reduced, certainly the livestock that get fed agricultural products rather than just grazing on land not well suited to traditional agriculture. Of course it may be that some of the non prim land may be suitable for some kind of biomass crop so soy curd all around everyone.

So there you go, without even increasing the amount of land devoted to food production/growing stuff how much biomass do those changes generate.
Click to expand...

I realize this sounds like something out of an Isaac Asimov story, but what if we had an entire planet of acceptable land for biofuel production? Say, Mars?




Just a fun thought :)

-Ian

"All models are wrong, but some are usefull" - George E. P. Box
 
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As far as depleating the soil, as in sugar beets, what is the difference between them and other crops? They all will deplete the soil if you don't add something back. Sure it's cheeper, and easer to use chemical fertlizers, but that is the problem with farming today. The rebuilding of the soils after a crop needs to include all the elements taken from it, not just N-P-K. That was the purpose of a manure spreaders was to add an organic mostly complete fertlizer back into the soil.

Now given that Minnesota is not well known for livestock, there maybe a local shortage of manure. This can be a problem. Another problem is that crop rotation isen't used anymore. Most backyard gardeners will tell you it is important, but big farmers don't do it.

As far as CFL's, I've had more problems with LED's failing, or the glue used just gives way. But then again most of my CFL's I got for free from the local electric company.
 
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cranky,

Legumes (beans, soybeans, clover) are the obvious counterexample. They will increase the nitrogen in the soil - they have a symbiotic relationship with some microbes, and "fix" nitrogen from the air.

Different crops have different effects on the soil. This is why "crop rotation" was born. Instead of having a field dedicated to corn, you would plant beans one year, corn the next and perhaps alfalfa for your livestock the next. The next field over could have the same rotation, but start on corn.
 
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Wasn't the subject poor substitutes for the real thing? KIDDING:)

Note to Admin: Would you please, please quit improving things?

Regards,

Mike
 
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Minnesota "Now given that Minnesota is not well known for livestock"? come on, have you ever been there? And "crop rotation isn't used anymore..." thats just hogwash
 
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Regarding nuclear fission, the number 1 major accident / 10,000 years of operation seems to be thrown around quite a bit in pro-nuclear literature. Sounds like a reasonable number, with our 500 some odd nuclear reactors in operation worldwide that would be once every 20 years. If nuclear suddenly went from 5% of global power to 50% or more using current technology would people really be able to stomach a Chernobyl or Fukushima level event every other year?

Comprehension is not understanding. Understanding is not wisdom. And it is wisdom that gives us the ability to apply what we know, to our real world situations
 
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Beet processing is an incredibly stinky process. Drive thru Ft Morgan Colorado any time of the day or night. A feedlot with 10,000 cattle would be an improvement. The beet trucks can't seem to keep the beets in the truck, so all the roads around there are like driving on grease during harvest.

I haven't seen natural gas-powered fuel cells mentioned? They appear to combine a widely distributed, cheap, fuel with a technology that is very scalable, and a conversion process that produces ~60% lower C emissions. An important consideration is that distribution losses of an electrical grid is eliminated (but yes, gas has to be pressurized to flow).
 
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i think there are "better" fission reactor designs. the problem is we've got some experience with the pressurised reactors we have today (good and bad experience ! ... you learn more form the bad experiences, unfortunately) but no experience with the un-tried designs. so no matter what they promise, it's hard to back them with no real world experience to draw on.
 
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Don't talk about the potential from non-fossil energy sources until you've read this book. He even does calcs on how long our uranium, thorium and seaborne uranium and thorium would last.

Without nuclear and without fossil fuels, there isn't going to be a future without some MAJOR adjustments to how people use energy, i.e. how and where they live, what they consume, how they get around, and how many of us there are.

Biofuels, geothermal, solar and wind are all partial solutions, with benefits and consequences depending on what you use them for and how you deploy them.

Take it from someone in the business: making liquid transport fuels from non-food biomass is a tricky, expensive business. It's way easier to dig or pump fossil carbon from the subsurface, refine it and use it. The most efficient way to use nonfood biomass to generate energy is to burn it to make low-grade comfort heat or to make electricity. On an energy returned per unt energy invested basis, you can only transport that bulky biomass a certain distance before you get less out of it than you invested to harvest and transport it.

Note also that intensive agriculture (i.e. what is used for food production) is not sustainable in most places at current yields without a hell of a lot of fossil fuel-derived fertilizer.

People don't make major changes to how they live unless they're forced to, and then they do it reluctantly. Even making them pay more doesn't do it very well. There is tremendous elasticity in the energy use supply/demand equation.

The only thing which works less effectively at reducing energy consumption than making people pay more for the energy they use, is NOT making them pay for it.

Until there's a cost to dumping bad things into the atmosphere, people will prefer to dump sh*t into the atmosphere because it's cheap and convenient to do so. You can't run an energy industry entirely on government subsidy.

Fortunately, frac'ing has generated a bumper crop of natural gas in North America, allowing us to leave more of the worst fossil carbon (coal, tar sand and oil shale) in the ground for a while longer- if we choose to. However, the cheap NG makes it cheaper to exploit tar sand too, and the differential in price between oil and gas promotes what I consider to be energetically wasteful technologies such as SAGD for tar sand and Fischer-Tropsch conversion of natural gas. As the easier sources of liquids become scarcer and hence more expensive, carbon intensity to recover those fuels will inevitably increase.
 
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Eh, being willing to use fast breeder reactors increases effective uranium by about 100x, since we will use all of it instead of just the (<1%) U235. Thorium is even more prevalent than uranium. Reprocessing "spent" fuel increases energy further. Plenty of energy to provide 100% of world electricity for centuries.

On the engineering side, nuclear is a solved problem. Social/political/cost issues remain. Cost is driven in large part by the social and political issues.

As you noted, non-food biomass is not really a solved problem - at least not at a useful scale.
 
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TomDOT, while nitrogen fixation is important in crop rotation, but it dosen't fix other soil deplations. Which is the point of using bio derived fertlizers. Many farmers don't even use crop rotation, just add factory made stuff.

I can get behind green, if you can tell me what is green and non-objectionable. That's my objection to nucular, wind, biomass, etc. It's not the concept, it's the attitude that we have to fight anything we disagree with. And suprise someone always disagrees.
Fix the attitude, that some times we need to accept something we disagree with for the greater good. Make things positive, by not being negitive to everything.
 
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I agree, "Hot Air" should be required reading. Another book I really liked (you'll have to buy it unfortunately) it "The Solar Fraud". Rhetoric is a little pointed at times, but the physics is dead on.

Regards,

Mike
 
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Correction!!

This source: is wrong by 3 orders of magnitude in the amount of solar energy hitting the earth. I had said earlier that there wasn't enough solar to replace the amount of energy we need on a daily basis; that is now completely wrong. There's craptons of solar, if we can just harness it.

The issue, as pointed out earlier, us that if you're using farmable land to produce biofuels, we can't eat. So I'll ask again: someone tell me what's going on with algae? Theoretical outputs are way higher than soy or corn, so what's the holdup? How can it be so hard to grow? I'm sitting next to a pond full of the stuff right now - are wetlands going to end up being outrageously economically productive?

And come on - if the Native Americans could take grass and domesticate it into corn, what the heck is our problem? We can sequence genomes and splice anything we want in there!
 
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