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Start-Up Uses Plant Seeds for a Biofuel

nytimes.com

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Re: Start-Up Uses Plant Seeds for a Biofuel

#31

Post by ars »

icegreentea wrote: post #30
ars wrote: post #24

Earlier quoted context omitted.

So lets save the expensive oil for transportation and stop burning it in fixed installations. The are plenty of electrical plants that burn oil.

Because even if you rationed oil for transportation, it's still going to grow sparse - and there's no reason to believe that the demand for transportation is going to go down. At best, the rationing scheme will slow down the current problem, and then you're back to where they are right now, trying to find viable and cheaper replacements for oil.

Lets solve the easy problems first.

Plus you can make oil from air plus energy. Coal plus water is even easier.

All we need to do is reduce the cost somewhat, it's not necessary to solve it fully.

Re: Start-Up Uses Plant Seeds for a Biofuel

#32

Post by ChuckMcM »

dredmorbius wrote: post #27
ChuckMcM wrote: post #10

Earlier quoted context omitted.

Pardon me for being a bit pedantic here but not all bio fuels require farmland. Bacterial based processes (generally e.coli) work in digestor/reactors), algae based fuels simply need access to sunlight (can be grown in tubes attached to the side of buildings). Further some starter crops can use land that is not deemed arable by farming standards.

The scale at which algae would have to be produced to provide even a small fraction of existing petroleum consumption would mean you'd be growing it on rather more area than you've got affixed to building facades. For the US alone, sever tens of millions of acres, at 15,625 square miles (40,468 km^2) per 10 million acres. If you were, say, build your 10 million acres of algae grow tanks along the length of US Interst…

You could grow algae in clear tubes across 15 square miles of the Mohave desert and not consume a single acre of arable farmland.

Re: Start-Up Uses Plant Seeds for a Biofuel

#33

Post by dredmorbius »

ChuckMcM wrote: post #32
dredmorbius wrote: post #27

Earlier quoted context omitted.

The scale at which algae would have to be produced to provide even a small fraction of existing petroleum consumption would mean you'd be growing it on rather more area than you've got affixed to building facades. For the US alone, sever tens of millions of acres, at 15,625 square miles (40,468 km^2) per 10 million acres. If you were, say, build your 10 million acres of algae grow tanks along the length of US Interst…

You could grow algae in clear tubes across 15 square miles of the Mohave desert and not consume a single acre of arable farmland.

Where are you going to get the water from?

If it's seawater, how are you going to return it to the ocean. You can't dump salt water on land -- it poisons the soil. Even freshwater evaporating in dry climates leads to salinization.

What's that going to cost you in energy inputs (pumping costs)?

Though the thought occurs to me that the Salton Sea in southern California might make a possibly suitable grow region.

Re: Start-Up Uses Plant Seeds for a Biofuel

#34

Post by ChuckMcM »

dredmorbius wrote: post #33
ChuckMcM wrote: post #32

Earlier quoted context omitted.

You could grow algae in clear tubes across 15 square miles of the Mohave desert and not consume a single acre of arable farmland.

Where are you going to get the water from? If it's seawater, how are you going to return it to the ocean. You can't dump salt water on land -- it poisons the soil. Even freshwater evaporating in dry climates leads to salinization. What's that going to cost you in energy inputs (pumping costs)? Though the thought occurs to me that the Salton Sea in southern California might make a possibly suitable grow region.

If we've posited a desert based system, I'm going to guess it is closed loop with respect to water (which is to say the water never leaves the system as anything except perhaps evaporation during post processing.) So the initial water budget probably comes from the aquifer or is imported. Once the system is running an interesting question is how much water would it lose over time.

And while that is an interesting question, it doesn't change the situation that no farmland was harmed in the process. :-)

Re: Start-Up Uses Plant Seeds for a Biofuel

#35

Post by dredmorbius »

ChuckMcM wrote: post #34
dredmorbius wrote: post #33

Earlier quoted context omitted.

Where are you going to get the water from? If it's seawater, how are you going to return it to the ocean. You can't dump salt water on land -- it poisons the soil. Even freshwater evaporating in dry climates leads to salinization. What's that going to cost you in energy inputs (pumping costs)? Though the thought occurs to me that the Salton Sea in southern California might make a possibly suitable grow region.

If we've posited a desert based system, I'm going to guess it is closed loop with respect to water (which is to say the water never leaves the system as anything except perhaps evaporation during post processing.) So the initial water budget probably comes from the aquifer or is imported. Once the system is running an interesting question is how much water would it lose over time. And while that is an interesting que…

For a system comprising tens to hundreds of millions of acres, incidental and transpiration water losses are going to be nontrivial.

Hermetically sealing such a system would be ... prohibitively expensive.

You'll be pumping water in from somewhere.

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