111–120 of 130 posts
It simply puts real numbers against various different ways of getting our energy, and in terms of EROEI (Energy Returned on Energy Invested).
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>>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.
Since we've already flown electric planes that statement is, in a weird way, actually true. They've already been "electrified."
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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.
Also this is something of an enviro-slur but renewable ideas are typically horribly polluting but the small scale types handwave past it. A gasoline engine can output exhaust cleaner in some ways than its input air, especially WRT hydrocarbons in smoggy areas, but a coke/charcoal oven is just beyond filthy polluting, which scales pretty well to one dude and his one car but is a non-starter for 100M American cars. The interstate would be unimaginable.
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…
However, if you move the process out into the desert and use concentrated solar power to provide the heat then you have a solar power process running at 50% efficiency to produce a stable portable store of energy, which makes a lot more sense.
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> 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…
Its a way to convert one sort of energy to another. E.g. solar to petro. Its sensible, has a place in our economy, and is not ignorant, though the article didn't make this all clear.
Doing some very, very rough estimates, I figured we would might be able to take 20 barrels of algae slurry, "cook" them (@ 350°C & 3000 PSI) for a thousand hours and get one barrel of petrol. Little or no mention of other inputs/processes involved.
My point is, we will be able to do this if we have to, but it will not be cheap, and even if we have the money we may not have other resources to do it at large scale. Like... to make it available for all motorists in the world to drive happily ever after. It is more likely that this will be an strategic resource that governments will use to fulfill needs that cannot be fulfilled any other way (like (military) aviation... you cannot just stick a Mr.Fusion in the tale of a plane and go to the infinity and beyond).
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But is it better than turning that geothermal energy into electricity and transmitting it to a battery in an electric car? Edit: To be clear, I'm not saying there isn't a need for oil. Just wondering what the efficiencies are for each route, and whether this process means that we don't even need electric cars any more (doubtful, but I thought I'd ask)
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
I think planes, rockets and various military applications (e.g an infanterist carrying a zillion gadgets that have to be powered for hours) are the only examples of cases where this process might be beneficial.
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As green as it gets, since the CO2 that is released from burning the fuel has been taken out of the atmosphere by the algae a short time before that. The only issue is to take care of the byproducts and algae production process, which can create local pollution issues - cheaper not to do it, but nothing that hasn't been done before in sufficient scale.
> As green as it gets The massively polluted by oil derivative combustion atmospheres of L.A., Mexico City and Beijing beg to differ.
Of course local pollution is a concern, but it will always be wherever there are high concentration of people around.
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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 stirlin…
(That's a marine engine though. Larger engines are more efficient.)
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My claim is that the energy equation is independent of oil availability. We aren't going to "run out of energy" as some people postulate. Knowing that is helpful sometimes. You might want to check the EROEI numbers for algae fuels, the NASA paper suggests that they are lower than they are for oil. They make that claim based on lower transportation costs (feedstock is made 'onsite' of the refinery), and a simpler refi…
Your original claim was that because of economic laws ($500/barrel argument) we will never run out of petrol. (ergo, will be able to find a way to violate laws of physics, because we want to). If you now want to change your argument and discuss why and how is this technology going to solve our energy problems, I am all ears.
First, a nit pick, I said "oil" (not petrol) but petrol is a product made from oil and mentioned in the article so its not a big deal.
My claim is that we can make "petrol" out of the air if we want [1]. It does not violate any laws of physics (or thermodynamics). Using petrol to make petrol this way is not effective since the translation leaves you will less petrol than you started with. Using power supplied by a nuclear reaction (as an example) to make petrol this way will convert locally generated nuclear power into transportable "chemical" aka "petrol" power. As most of the energy in the fischer-tropsch process is heat you can use concentrated solar just as easily. the electrical energy used is primarily in running the cooling pumps. Given that "oil" (and from oil, petrol) can be made out of renewable feedstock (CO and H2), I claim we won't ever "run out".
The economic principle I was alluding too was substitution, where an equally effective good at lower cost replaces a good at higher cost in the market. If petrol is $10/liter, cars powered by electricity will replace cars powered by petrol. That is an economic substitution of equal function at a lower cost.
On the Algae process. At least the NASA version required much less heat and cooling the the fischer-tropsch process and in the NASA case no arable farmland (you can grow algae in clear tubes bolted to the sides of buildings if you want). Providing yet another alternative to acquiring long chain hydrocarbons that are more cost effective to create than using a nuclear reactor connected to a Fischer-Tropsch reactor. The challenge of algae systems has been capturing a low marginal cost of additional oil from a process that was not continuous (you want to make a gallon you pay the cost of running the cycle for 1,000 gallons regardless). If however you can make a gallon for the marginal cost of producing an extra few gallons of algage scum, then you can amortize your costs more effectively and carry less risk. Both of these things encourage adoption and production.
Is that clearer? And for the record I don't think I've changed my argument at all here, just filling in the bits which you might have missed.
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My claim is that the energy equation is independent of oil availability. We aren't going to "run out of energy" as some people postulate. Knowing that is helpful sometimes. You might want to check the EROEI numbers for algae fuels, the NASA paper suggests that they are lower than they are for oil. They make that claim based on lower transportation costs (feedstock is made 'onsite' of the refinery), and a simpler refi…
"We aren't going to "run out of energy" as some people postulate." Why?
[1] in the literal sense forever here is 1000's of years, the exemplar is a either a breeder reactor (demonstrated) so thorium reactor (proposed)