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

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

#51

Post by toomuchtodo »

jccooper wrote: post #26
dagw wrote: post #13

Earlier quoted context omitted.

Sure, that's better in the few scenarios when it is reasonable to do so. But electric engine technology is still very limited, and we're a long way from replacing all internal combustion engines with electrical. I doubt we'll seeing transatlantic passenger flights in electric airplanes any time soon. The other huge advantage with oil is that it is a very efficient, stable and easy to transport store of energy. Transp…

I'm petty sure I'm being pedantic, but to be clear: Electric engines (motors) are great. Highly efficient, simple, powerful, scalable both ways, and reliable. If you've got electricity available and want things to move, they're the way to go. It's the batteries that are sub par, in many ways.

That's exactly why diesel locomotives have always been diesel generators connected to massive electric motors; the best of both worlds.

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

#52

Post by toomuchtodo »

hcarvalhoalves wrote: post #43
peg_leg wrote: post #30

I'm still against it. Burning caloric mass for energy when so much energy is around us is just plain ignorant. We need to move to solar and wind power.

> Burning caloric mass for energy when so much energy is around us is just plain ignorant. No it isn't. What the algae does is exactly it: harness all that "energy around us", which is scattered around and hard to get, in a more efficient manner.

Burning the resulting synthetic petroleum is still highly inefficient; you're only going to get 1-5% total efficiency with most of the energy being converted to waste heat.

I could see this being used to generate fuel on-site at remote airports or places where its difficult to truck liquid fuel, but electricity is still going to be the way to go. Its just too easy to move it (with HV transmission lines) compared to large amounts of liquid fuel.

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

#53

Post by [deleted] »

xexers wrote: post #47
mseebach wrote: post #36

Earlier quoted context omitted.

The energy content in algae comes from the sun, so this is solar energy, just being captured in the form of liquid hydrocarbons instead of electricity.

I understand that... but aren't you still going to have smoggy cities with biofuels? Even if they are net carbon neutral, they suck up carbon while being produced and then are burned in cars driving in the city, thus creating smog in the city... smog which has all kinds of health problems.

[deleted]

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

#54

Post by pjc50 »

VLM wrote: post #18
pjc50 wrote: post #4

Earlier quoted context omitted.

The algae->oil part of the process necessarily loses energy, so it all comes down to the process of turning sun into algae. Which is not itself very efficient, but may be cheaply scalable. I think if you just care about renweable EROI and not about storage in convenient petrol form then wind and solar are still the winners.

"storage in convenient ... form" If you can't store it, you can't use it, so it doesn't matter how green it is, it won't be used. The ideal transportable liquid fuel is diesel with gasoline a very close second. Some peculiar and temporary engineering and economic issues make gasoline ideal for passenger cars but in a very long run perspective the whole world is going diesel, its just the future has arrived a little q…

Sure, but people use nonstorable electricity just fine, so I disagree with your first sentence.

Biogas rather than biodiesel might appear as a farm fuel in the future, either from manure or wood gasification. But not while underground gas is still cheap enough to flare.

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

#55

Post by angersock »

peg_leg wrote: post #30

I'm still against it. Burning caloric mass for energy when so much energy is around us is just plain ignorant. We need to move to solar and wind power.

You can't beat the energy density of hydrocarbon fuels for many applications. Sorry.

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

#56

Post by mseebach »

xexers wrote: post #47
mseebach wrote: post #36

Earlier quoted context omitted.

The energy content in algae comes from the sun, so this is solar energy, just being captured in the form of liquid hydrocarbons instead of electricity.

I understand that... but aren't you still going to have smoggy cities with biofuels? Even if they are net carbon neutral, they suck up carbon while being produced and then are burned in cars driving in the city, thus creating smog in the city... smog which has all kinds of health problems.

Yes, cars still pollute, although the bad smog we're seeing in eg. China has more to do with unclean combustion and no or poor filtering than is has to do with hydrocarbon fueled cars per se.

The reason a scalable carbon-neutral liquid hydrocarbon solution is attractive is that it's a drop-in solution to CO2 emissions. Battery-powered cars are neat and might well be the way of the future, but it's a very long play. Even if we had the money to replace all cars on the face of the planet with Priuses, there are some very significant constraints on the production on batteries in the form of rare earth minerals. Also, even if you did that, there's still trucks, ships and airplanes to address, never mind that most of the planet's electricity isn't exactly cleanly produced. The carbon-neutral liquid hydrocarbon solution on the other hand would be applicable without any of those constraints.

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

#57

Post by valarauc4 »

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.

As somebody who works in the fuel industry. We easily can keep about 3-5 liters of fuel at ~15,000 psi for injector testing in about ~1kw to 2kw watts of power (with 350F heating). So not super far off.

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

#58

Post by UnFleshedOne »

johnchristopher wrote: post #44
hobbes300 wrote: post #34

Earlier quoted context omitted.

> I struggled with the question of how to transport that energy to where we'd like to use it Lasers

Thus spoke our prophet: Let me tell you one of my pet peeves: space solar power. Okay, the stupidest thing ever. If anyone should like space solar power, it should be me. I got a rocket company and a solar company. I should be really on it, ya know. But it's like, super obviously, not going to work because, ya know, if you have solar panels - first of all, it has to be better than having solar panels on Earth, so the…

Isn't the point of solar in space, well, space? You get less efficiency, but you are not going to run out of deserts nearly as fast. So the ultimate scale is not limited.

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

#59

Post by eterm »

johnchristopher wrote: post #44
hobbes300 wrote: post #34

Earlier quoted context omitted.

> I struggled with the question of how to transport that energy to where we'd like to use it Lasers

Thus spoke our prophet: Let me tell you one of my pet peeves: space solar power. Okay, the stupidest thing ever. If anyone should like space solar power, it should be me. I got a rocket company and a solar company. I should be really on it, ya know. But it's like, super obviously, not going to work because, ya know, if you have solar panels - first of all, it has to be better than having solar panels on Earth, so the…

Can't we skip the conversion and use giant optical lenses to focus sunlight onto panels on earth? ;)

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

#60

Post by beat »

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 flaws: burning it destabilizes the atmosphere, and it's a fixed resource that will eventually run out. In the long game (>100 years, when humans could be around for millions more), nuclear fission has the same problem. So the only really stable, long-term sources of energy are solar (including indirect solar like wind) and geothermal (including indirect gravitational energy like tidal).

Energy storage: This is where liquid and gas fuels have a huge win and battery storage has a huge lose. It's probably impossible for batteries to achieve the density and convenience of gasoline and other liquids. They're safe, easy to handle, etc. Even though electric motors are several times more efficient than combustion motors, liquid fuel storage efficiency more than makes up for it. Plus it requires no change to existing infrastructure.

Energy conversion: This is more about how it's used. We want vehicles, right? So we have to consider the operational goals and constraints of vehicles.

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