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Algae to crude oil: Million-year natural process takes minutes in the lab

pnnl.gov

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Re: Algae to crude oil: Million-year natural process takes minutes in the lab

#91

Post by ars »

beat wrote: post #60

Something to keep in mind, and the source of much misunderstanding in alternative fuel discussions... there are really three different systems involved! Energy capture, energy storage, and energy conversion (converting stored energy to work). Energy capture: Fossil fuel has the unpleasant problem that the energy was captured long ago, over very time-consuming (millions of years) natural processes. So it carries two f…

> Energy conversion: This is more about how it's used. We want vehicles, right?

No.

A small amount of energy is used for vehicles, but far far far more is used for fixed installations. Vehicles get all the press though.

Re: Algae to crude oil: Million-year natural process takes minutes in the lab

#92

Post by farinasa »

enraged_camel wrote: post #66
ChuckMcM wrote: post #65

And this boys and girls: ""Cost is the big roadblock for algae-based fuel," said Douglas Elliott, the laboratory fellow who led the PNNL team's research. "We believe that the process we've created will help make algae biofuels much more economical." Is why we won't run out of 'oil' at any time. Even at $500/barrel equivalent there is a point where if you must have 'crude oil' you can make it for a price. Of course at…

>>Is why we won't run out of 'oil' at any time. Even at $500/barrel equivalent there is a point where if you must have 'crude oil' you can make it for a price. Of course at that point its a 'renewable resource' which is kind of funny. Well, yes. We won't run out of oil in the ground either. The Earth actually has enough reserves to last us for thousands of years. When people say we will "run out of oil" what they act…

>I mean, do you know what would happen to gas prices if we had to pay $500/barrel?

Hmm, I truly wonder if we would actually still run around like headless chickens still denying the viability of electric or if we would actually see it as a viable alternative. It seems people will fervently argue a side no matter how glum/impractical/uneconomical the situation is.

Re: Algae to crude oil: Million-year natural process takes minutes in the lab

#93

Post by beat »

grecy wrote: post #81
chaz wrote: post #15

Earlier quoted context omitted.

Gasoline has tremendous energy density compared to other forms of storage. If you need that energy to be portable (like in a car or truck), you may still want to use petroleum. http://en.wikipedia.org/wiki/Energy_density

Right, but that doesn't mean anything when we're only getting ~16% efficiency in our ICE.

It means a lot. The Tesla Model S (a reasonable sedan) needs 85kwh to reach a 300+ mile range, and the drivetrain is probably about as efficient as electric cars will ever be. So realistically, we need 85-100kwh of power on board a reasonable car.

A single gallon of gasoline is ~33kwh of power. At 30mpg (easy for a sedan), 10 gallons (330kwh) is sufficient for a 300 mile range. So the Tesla is ~4 times as energy efficient as internal combustion, and unlikely to get any better.

Re: Algae to crude oil: Million-year natural process takes minutes in the lab

#94

Post by farinasa »

grecy wrote: post #81
chaz wrote: post #15

Earlier quoted context omitted.

Gasoline has tremendous energy density compared to other forms of storage. If you need that energy to be portable (like in a car or truck), you may still want to use petroleum. http://en.wikipedia.org/wiki/Energy_density

Right, but that doesn't mean anything when we're only getting ~16% efficiency in our ICE.

Good thing we have been doing better than that for some time now.

>The MAN S80ME-C7 low speed diesel engines use 155 grams (5.5 oz) of fuel per kWh for an overall energy conversion efficiency of 54.4%

>The efficiency of a combined cycle gas turbine system can exceed 60%.

http://en.wikipedia.org/wiki/Diesel_engine#Fuel_economy

In fact, it's shameful how underutilized diesel engines are in this world. Same with stirling engines.

Re: Algae to crude oil: Million-year natural process takes minutes in the lab

#95

Post by wil421 »

shortly wrote: post #85
wil421 wrote: post #82

Doesnt this take away from the real issue of fossil fuels? Pollution, increased CO2 and climate changes. Lets say this could scale and be economical tomorrow. Does anyone think the oil companies would let that happen or let their price per gallon at the pump decrease.

> Doesnt this take away from the real issue of fossil fuels? Pollution, increased CO2 and climate changes. No. Any CO2 released when these fuels are burned has to come from the algae. The algae gets it from the air. So CO2 is cycled, but not added to the atmosphere.

For my understanding, the problem with the fossil fuels is that they are trapped in the ground and we are releasing the carbon that was trapped in the ground into the atmosphere.

Re: Algae to crude oil: Million-year natural process takes minutes in the lab

#96

Post by beat »

wil421 wrote: post #83
seren wrote: post #2

> The system runs at around 350 degrees Celsius (662 degrees Fahrenheit) at a pressure of around 3,000 PSI, combining processes known as hydrothermal liquefaction and catalytic hydrothermal gasification. I wonder what it the energy ROI of the whole process. It is not mentioned in the article, so it is not sure it is positive.

Gasification is a fascinating process I was just recently aware of. Some guy got his truck to run on a certain type of oak. https://www.youtube.com/watch?v=yYGKn12Weu4

Scalability is a fascinating process, too. But oak trees aren't scalable.

There are lots of ways to generate local "renewable" energy optima from waste products. Unfortunately, none of them scale.

Re: Algae to crude oil: Million-year natural process takes minutes in the lab

#97

Post by chaz »

grecy wrote: post #81
chaz wrote: post #15

Earlier quoted context omitted.

Gasoline has tremendous energy density compared to other forms of storage. If you need that energy to be portable (like in a car or truck), you may still want to use petroleum. http://en.wikipedia.org/wiki/Energy_density

Right, but that doesn't mean anything when we're only getting ~16% efficiency in our ICE.

Gasoline is still way ahead. It still has ~40x the density of batteries. Even at 16%, it's still going to be about 6x as efficient as batteries, even if batteries + electric motors are at 100% efficiency.

A Toyota Camry car carries 17 gallons of fuel, which, at 6 lbs per gallon, is about 100 lbs. At 28 mpg, that's enough to travel 476 miles. The Tesla S carries a 900 lb battery which is enough to travel about 250 miles. In miles per lb, that's 4.7 for the Toyota, and 0.28 for the Tesla.

Obviously, there are a lot of other considerations than just miles per lb, but gasoline's energy density and portability are stellar.

Re: Algae to crude oil: Million-year natural process takes minutes in the lab

#98

Post by Symmetry »

crpatino wrote: post #69
ChuckMcM wrote: post #65

And this boys and girls: ""Cost is the big roadblock for algae-based fuel," said Douglas Elliott, the laboratory fellow who led the PNNL team's research. "We believe that the process we've created will help make algae biofuels much more economical." Is why we won't run out of 'oil' at any time. Even at $500/barrel equivalent there is a point where if you must have 'crude oil' you can make it for a price. Of course at…

> Even at $500/barrel equivalent there is a point where if you must have 'crude oil' you can make it for a price. Sorry, but this is just ignorant nonsense. EROEI is what counts here, not raw "profits". If your $500/barrel price point was calculated using inputs that require total energy investment equivalent to 2 barrels of oil @ $150/barrel... this is a stupid way of burning perfectly good and relatively cheap natu…

EROEI only matters if this is your only source of energy. At $500/barrel it would make sense to use solar power for the energy intensive bits. Nothing says your conversion plant has to run day and night.

Re: Algae to crude oil: Million-year natural process takes minutes in the lab

#99

Post by tedsanders »

enraged_camel wrote: post #66
ChuckMcM wrote: post #65

And this boys and girls: ""Cost is the big roadblock for algae-based fuel," said Douglas Elliott, the laboratory fellow who led the PNNL team's research. "We believe that the process we've created will help make algae biofuels much more economical." Is why we won't run out of 'oil' at any time. Even at $500/barrel equivalent there is a point where if you must have 'crude oil' you can make it for a price. Of course at…

>>Is why we won't run out of 'oil' at any time. Even at $500/barrel equivalent there is a point where if you must have 'crude oil' you can make it for a price. Of course at that point its a 'renewable resource' which is kind of funny. Well, yes. We won't run out of oil in the ground either. The Earth actually has enough reserves to last us for thousands of years. When people say we will "run out of oil" what they act…

Cars, ships, and trains may be electrified, but I don't think planes will ever be electrified. A huge advantage of fossil fuels over batteries is energy density, and energy density is very important for planes.

Re: Algae to crude oil: Million-year natural process takes minutes in the lab

#100

Post by brc »

Symmetry wrote: post #98
crpatino wrote: post #69

Earlier quoted context omitted.

> Even at $500/barrel equivalent there is a point where if you must have 'crude oil' you can make it for a price. Sorry, but this is just ignorant nonsense. EROEI is what counts here, not raw "profits". If your $500/barrel price point was calculated using inputs that require total energy investment equivalent to 2 barrels of oil @ $150/barrel... this is a stupid way of burning perfectly good and relatively cheap natu…

EROEI only matters if this is your only source of energy. At $500/barrel it would make sense to use solar power for the energy intensive bits. Nothing says your conversion plant has to run day and night.

You say that like solar power is free. To calculate the EROEI, you have to include the energy from solar.
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