More green than using the fossil fuel to turn the wood into paper and then sequestering it into a landfill when you’re done?
There is also the option of using high pressure air as a propellant. So any increase in engine efficiency gained through a novel design is to be encouraged.
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Possibly not! I suppose technically it would depend on the paper production process and the landfill. Paper degrades pretty fast in our local landfill, but then again the local landfill churns everything up pretty good and generates a lot of natgas.
I’ve often thought that handcrafting heirloom furniture from wood is a nice way to tie up atmospheric carbon.
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I was thinking of cellulose-based biofuel. CF “Sustainable Energy without the hot air,” which calculates that replacing petrol with biofuels would require setting aside really large areas of land for growing the cellulose (I forget what the best crop is - hemp? or something else?).
https://www.withouthotair.com/
If you use cellulose derived methanol or electricity instead of diesel to run the agricultural machines, then biofuel is carbon neutral by definition. I won’t say the same about the government subsidized ethanol fuel program in the US, which is basically an ecologically destructive corn grower’s subsidy program in greenwashed disguise.
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on one hand, we’re not quite in the ‘end’ just yet. But I don’t want to seem to disagree with your sound points on energy density and such.
We -can- make hydrogen with nearly any technology that can create electricity, so that has to include stationary wind and solar and hydro sources. We might pick nits about -zero- pollution levels or trade-offs - but carbon-neutrality is nearly possible if not achievable.
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Can’t say that often enough! Bush II has a lot to answer for…
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Mazda have their SKYACTIV-X and I can see decent markets for small, very compact IC engines as hybrid powerplant components over the next 30 years or so, even as electric takes a lot of the market.
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Fuel cells are fine for some applications but their power output is modest and fixed. Cars need to provide rapid bursts of power for acceleration, which IC engines and batteries are ideal for. So you would have to buffer the output of the fuel cell with a battery and if you model it I think you will finish up just using the batteries.
Its similar to why turbine engines didn’t work out for cars. They can cruise fine but not accelerate.
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You seem really stingy on providing a single citation of a new combustion engine providing a smaller carbon footprint than a new electric engine (serving the same power needs, obvs).
I am not asking for you or anyone else to “point it out,” I am asking for a reliable citation.
Am looking for data and analysis, not persuasion and argument.
Because that isn’t my point. Engine to engine of course it isn’t going to produce less carbon. My point is that the overall ecological impact, including carbon emissions, might be the same. Get your electricity from a coal plant having coal trucked in? Going to be much more similar. Get it from a wind farm, then it is going to be much better. The problem is, it is really hard to hard quantify all the numbers - vs just quantifying engine vs engine emissions.
But here is an over view:
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Yeah, but the disadvantage of using compressed air is the huge energy inefficiencies that are an inherent limitation of physics, not engineering. When you compress air you get adiabatic heating, even in a perfect, frictionless compressor. Unless your air tank can be perfectly insulated and allowed to be safely heated to thousands of degrees, you need to let it cool off during compression, so the heat becomes wasted energy. Even if you then run the compressed air through a perfect, frictionless air powered motor, (which will require additional heat input from ambient air or some other source to keep from freezing from adiabatic expansion, BTW) you’re still less efficient overall than if you use a modern ICE or electric car.
None of that is meant to imply that engines designs that reduce friction aren’t a great thing, though.
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From wiki:
An estimated 323 million tons of cellulose-containing raw materials which could be used to create ethanol are thrown away each year in US alone. This includes 36.8 million dry tons of urban wood wastes, 90.5 million dry tons of primary mill residues, 45 million dry tons of forest residues, and 150.7 million dry tons of corn stover and wheat straw.[53]
And that is not counting growing sustainable crops like switchgrass which requires far less inputs than corn. Think about the metabolic efficiency of harvesting from a perennial root system rather than a plant that has to generate all that from scratch every year. We spend tremendous amounts of money and energy growing and harvesting cellulose only to landfill it or compost it. We should be doing cellulosic in addition to solar and wind electricity. Had oil stayed above $120/barrel we’d have seen this commercialized by now.
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Eh I think your splitting hairs there. We probably get more fuel out of a crop by processing methyl rather than ethyl alcohol.
Your still locking more land up in industrialised farming monoculture (for fuel instead of food) which is not environmentally benign or even inert. The processesing of either sugar or cellulose is like wise not environmentally inert.
And both processes are only as green/carbon neutral and the infrastructure around them. It’s still an “eventually” and “if” situation. If the electrical grid is sustainable. If there are farming machines you can run off the green fuel itself. If transpiration Both before and after processessing are both similarly green. And so on. It’s still an infrastructural problem. And the particulars are largely identical. Intensively farming 50,000 acres of hemp isnt at all better for anything than intensively farming 50,00 acres of corn. Or wheat. Or quinoia.
And either approach still needs a clean system already in place before they’re clean. Wither fuel still tends to output more carbon then the plants pull from the atmosphere when burned, because plants also tends to extract sequestered carbon from the soil. So it’s a slow/stall rather than reverse situation. Methanol isn’t a magic bullet just cause it sounds better in a headline.
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Methanol, or something like it, is the answer to the question “how will we fuel the engines that cannot be electrified if we stop using fossil fuels completely?” It’s not a magic bullet, it’s part of a wholistic long term solution to switching the planet to 100% sustainable energy sources.
eta: Ethanol biofuels are produced from food via yeast. So you’re using just a tiny fraction of the crop, and you’re using something that otherwise could be fed to humans or livestock. It’s a really stupid approach to making biofuel. To make methanol, all you need to do is destructive distillation of plant matter. As a bonus, you get charcoal, which can be ploughed back into the agricultural field to enhance its fertility.
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Besides the downsides others have mentioned, most fuel cell tech uses hydrogen as fuel. Other fuels for fuel cells exist in the laboratory but are even less ready for prime time than hydrogen fuel cells.
Outside of the car industry propaganda that was used to kill California’s 1990’s requirement that a certain percentage of cars be emission free, hydrogen is a really lousy fuel. The energy density is extremely low even if you compress the hell out of it, so you end up with a big, heavy, spherical fuel tank that takes up more room than batteries would for the same range. It’s a flammable gas like methane, but if you adulterate it enough to have an odour, you’re going to kill the fuel cell with contaminants, so if the tank leaks, you won’t know it until you are on fire. And the energy required to obtain hydrogen without producing carbon emissions is ridiculously high, so the efficiency of the overall system is really extremely poor. I am sure there are more downsides I have forgotten.
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Thank you!
However, while I very much agree that we need to take a comprehensive accounting of environmental impacts of our technologies, your cited article says (emphasis added):
“We’re shifting pollution, and in the process we’re hoping that it doesn’t have the environmental impact,” says Abraham. He believes that when you add all the environmental impacts, they still come out in favor of electric vehicles. (The Union of Concerned Scientists agrees; it found that even when you add in emissions from battery manufacturing, EVs generate half the emissions of a conventional car over the course of its life.)
You originally wrote:
Well, no, but the whole “point” of “electric good, gas bad” is the emissions and carbon foot print, which depending on what you are running your power plant with, and how it gets to that power plant can be as bad or worse, or only marginally better.
I do not think halving the carbon footprint is “as bad, worse, or only marginally better.” And, indeed, the overall carbon emissions are not the same.
Full disclosure: I do not own a car.
Well dammit. That is all.
These people are probably further along the path to application. (including a $1mil darpa project) I swore I heard about them here, but I couldn’t find any articles with a search.
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There are processes for getting ethanol out of the rest of the crop. The rest of the crop can be processed for methanol. There are processes in the works using things other than yeast. And even without those those other portions of the plant can be used for something else. Including animal feed (where they were edible) and fertilizer (compost!).
The crops typically used. Especially the corn in question. Aren’t usually the sorts of crops used for food. Different varietals grown specifically for industrial processing. While some of the products coming out of those (like say processed soy bean oils, modified food starch/corn starch, and various grade of corn syrup) may have ended up in the food system. And I think there is some cross over between animal feed varieties and processing varieties of corn at least. Ethanol grows out of and lives in the end of agriculture that’s already primarily about chemical processing.
The rise in corn prices/pressure on the market isn’t so much about taking food and selling it for something else as it is about switching land use over from growing food crops. To growing industrial crops for processing. Methanol still has that same problem. Land you use to grow hemp for methanol. Is land you aren’t growing food on. So you’ve either destructively cleared new land, or converted food producing land.
Because you aren’t going to replace the volume of fossil fuels we use without large growing operations and heavy production. And last I check the traditional feed stock for methanol production was CORN!
Large, intensive monoculture operations are bad for the environment generally. They’re hell on soil quality. Involve intense use of fertilizers, pesticides, and herbicides (often made from CORN!). They prompt erosion. Especially of top soil. And where all that shit washes into water shed and wetlands it causes massive damage to ocean ecosystems. The ocean being our major carbon sink, and already off kilter enough to accelerate global warming without much further input. And these sorts of farms are murder on biodiversity across the entire ecosystem.
A process that typically releases a large amount of carbon into the atmosphere.
You know what else charcoal does? Releases a whole hell of a lot of carbon into the atmosphere when you burn it. We’re sort of at a loss for what to do with all the other sorts of coal we have and produce at the moment. So I suspect it would really become waste. Waste that sequesters some carbon, but still. Though there are some other in the year 2000 ideas out there that require ample supply of mostly pure carbon.
More seriously every complaint you have about ethanol is pretty much there about methanol. Most of the positives you cite could be just as true of ethanol under the one day maybe system you’re indicating. Neither is particularly green at the moment. And won’t be until our infrastructure around energy and farming are completely different.
Methanol probably produces more fuel by weight of grown crop though, because currently one practical process uses the whole plant to out put one sort of fuel.
Personally I like the sound of those algae and yeast/bacteria breeding tanks and digestors better. Can be done in a large warehouse, doesn’t involve farming at all. Put outs more fuel. And there are versions operating for ethanol, methanol, biodeisel and some other alternative fuels in the works. Some of the digestors you essentially toss garbage in the top and get fuel out the bottom. But those aren’t really producing much (if any) volume ATM. So mixing them into our current, really, real system. Doesn’t reduce overall carbon output. Ethanol, and if it was a market force Methanol. Might. Its the same calculus on fracked natural gas. In so far as it displaces (and has mostly displaced) mined coal. Its reduced environmental damage and carbon emissions.
