411–420 of 589 posts
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re: waste heat, I've been thinking forever that someone must capture this. I've generally assumed the economics don't work out or no one has cracked it outside of scenarios like regenerative braking. We waste so much energy that we could capture and put back to use.
Something like 55-60% of the thermal energy created by burning fossil fuels is currently wasted.
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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.
Well, the speed depends entirely on how fast the pump is. Some are faster than others, but I never have to wait for a spot, and printing a receipt takes 5 seconds. Maybe diesel pumps are faster? I sometimes use the truck pumps at freeway service centres, and it comes out like a firehose. Only 130 miles? Is that normal? My car can easily go 600 miles on a 15 gallon tank (diesel), but I've had it for so long I don't re…
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Yes, one of the things that gets glossed over many times in this field (I used to do research in artificial photosynthesis) is that water gets consumed to create the fuel, and is released as vapor from every engine's exhaust. So to generate 10 million barrels requires about 10 millions barrels of pure water, per day, to satiate the US.
Yes, water is turned into fuel and oxygen. In most places the water can be obtained from moisture in the air (there is much more water than CO2 in air, and we are already mining the air, so we can get both). In the process the fuel is separated from the water, which remains in the reactor, and is topped off as it is used to make the fuel. No waste water.
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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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* producing solar panels and such also requires energy input, and these do have limited lifetime. What is the real full-cycle energy conversion ratio is? I wonder what this is, too, but a typical 300W panel with 20 year lifespan will generate something like 20MWh over its lifetime. You can't possibly use anywhere near that much energy to manufacture it.
My personal pet theory is that the energy consumption is more or less equivalent to the price. So as long as the solar panel is not economically viable, it does not provide an energy surplus. 20MWh is not much, it's $500-$3000 worth of energy, depending on taxes and stuff. Can you buy, install, connect, maintain, clean a 300W solar panel for 20 years for this price? Edit: Also, 20MWh is quite high. That's 9h of perfe…
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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!
If the alcohol upgrade to gasoline makes sense technically and economically for you, why is it not commonly done with (presumably much cheaper and extant in great volume) industrial alcohol today?
A lot of conspiracy theories are paranoid, but the propaganda machine of the oil industry is very real and managed to incite a lot of economically counter-productive policies.
You mentioned use nanotube to extract alcohol, is this process similar to chromatography? Do your nanotube's half-life long and stable, and the production now is in industrial scale and low-cost?
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Gasoline. Each metric ton of CO2 corresponds to approx. 113 gallons of gasoline. The amount of water is approx. 1:1 by volume.
Very rough calculation: * 60 kWh / gallon of gasoline * 100,000 gallons / year * = 6 GWh / year * = 3.5 MW solar array (from on-line calculator) * ~ 18,000 m^2 of solar panels (500W, 1.9m * 1.3m) (roughly 3 football fields of solar panels).
I'm skeptical, but fascinated by what you're doing. It sounds like all of the steps of your process are known, except: 1. CO2 fixation uses only electricity - no natural gas or other fossil fuels. It works at room temperature. 2. Distillation of the immediate products (alcohols) is not necessary. A carbon nanotube membrane solves the problem at room temperature through reverse osmosis. Correct? If so, then why target…