501–510 of 589 posts
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CO2 seems much worse pollutant than water long term, because it stays in the air. Water at high altitudes condenses, reflects some radiation back to space and then falls back down.
At high altitude, the water stays up long enough and has such a huge impact that even its long term averaged impact is greater than the CO2.
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The thought is kind of horrifying, but you could even make it a closed process - send your old phone to the factory, where it's burned to produce the plastics for your new phone.
That would open up a pretty good avenue for "recycling" then, and could possibly reduce waste plastic in the environment
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Jevon's paradox only applies because governments subsidize fossil fuels by failing to correct the market failure of their externalities. If they were taxed appropriately to compensate for the damage they do then synthetic hydrocarbon fuels would probably be viable in the cases where batteries are unsuitable because of insufficient energy density (e.g. long-distance aviation).
No. I think you really need to understand Jevon's paradox. I highly encourage you to do so - once I learned about it so much of the world became clearer.
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We expect a gallon of gasoline to require approx. 60 kWh of electrical energy. If the price of that electricity is below 5 cents, the economics work. If the price is lower, the efficiency of the conversion could also be lower if that optimized other costs (like capital). Electricity is routinely below 5 cents now at utility scale (wholesale), which is where we will want to be.
60 kWh capacity EV will get you (realisticaly) 200 miles. A gallon of petrol - 40 miles (realistcally and using UK gallon). According to Tesla their charging is 92% efficient so reduce that 200 to 184 miles. Your process is 4.5 times less efficient than just putting that electricity into the EV? Is that right? If so - and your process is carbon neutral (big if) - what's the point in a future where EVs dominate?
How could the math possibly work out on this? If a gallon of gas holds 33.70 kWh of energy, and you can get cheap electricity for $0.1/kWh, you're looking at $3.37/gallon if you have a magical process that converts with 100% efficiency. Even if you hit your efficiency goal, which would be impressive, who is paying $7/gallon for gas? Just buy an electric car. This can only possibly be useful when all of the oil is gon…
who is paying $7/gallon for gas? In the UK, people pay approx $6 per gallon for gasoline.
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But nobody makes trips to the gas station to refuel. Re-fueling is something that's done on the way at a convenient gas bar, and typically takes only 2–3 minutes.
I’m very skeptical about 2-3 minutes. Maybe if you disregard lost momentum and don’t keep track of your mileage or wait for a receipt or have to go around once or twice to find a spot or... Because I keep track of my mileage and have to carefully babysit the process (likes to overflow) I’d say I lose at least 10 minutes every time I get gas, and that’s every 130 miles or so.
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Automatic factory on Mars?
You could make a lot of stuff from the CO2 in the Martian atmosphere, for sure!
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We could use the alcohols as fuels directly (in flex fuel vehicles), but this wouldn't address the much larger market for gasoline. It's a simple and inexpensive upgrade, so makes sense to do it. We will definitely take advantage of carbon credits, tax incentives, etc too!
Organic feedstocks (non-fuel), although smaller isn't exactly a tiny market. Depending on how much control you have over the fixation process you might be able to tap into some high-value alcohol markets. That's the main reason I added the follow-up to the original questions. In other words, the flow of material would look like: CO2 -> polymers, drugs, and other useful solid materials There would be no [product] -> C…
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> Even once cars are all electric, I can’t see gas turbine engines in planes, trains and ships being replaced in a hurry. Of course most (non-electric) train engines use Diesel-electric propulsion ( https://en.wikipedia.org/wiki/Diesel%E2%80%93electric_transm... ). That's mostly because of the flat torque curve of the electric motor. Some ships do too. I'm not sure why you think that battery-electric train engines or…
A fun usage of dimensional analysis: Fuel capacity of a diesel electric locomotive: 6200 gallons Energy density of diesel fuel: 40kWh/gal Total energy capacity of full fuel load: 248 megawatt hours Tesla battery pack weight: 540kg Tesla energy capacity: 85kWh Weight of equivalent battery pack for a diesel locomotive: 248 MWh / (85 kWh / 540 kg) = 1575 metric tons Weight of a diesel locomotive: 196 metric tons So you'…
The side effect of not needing to use energy to haul your energy source around is pretty cool, too.
I may well be off the mark here, so would appreciate it if someone could tell me what I’m missing.