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>If you pull your funding out of oil and gas, less scrupulous people will take their place and happily rake in the profits, Agreed. You create opportunity for

>If you pull your funding out of oil and gas, less scrupulous people will take their place and happily rake in the profits, Agreed. You create opportunity for at least a short term advantage. >make alternative energy cheaper, and the demand for oil and gas will disappear IDK, it seems the actual demand for oil will remain high. We’ll shift from using it in energy production and transportation to plastics, manufacturing, lubes and other refined oils, aviation which to shift to electric will need another 50 years of battery tech it seems, etc.

darksaints 7y ago
> IDK, it seems the actual demand for oil will remain high. We’ll shift from using it in energy production and transportation to plastics, manufacturing, lubes and other refined oils, aviation which to shift to electric will need another 50 years of battery tech it seems, etc. Agreed on the uses for oil, but I think planes are a lot closer than you think, but not via batteries. Fuel cells will be what is used, IMO. All of their disadvantages that make them a terrible fit for cars are pretty much null for planes. Electric motors are reaching 15 kw/kg. SOFC designs are now reaching 2.5 kw/kg power density and > 60% efficiency. With waste heat recovery, 80% efficiency is on the horizon. All combined, my napkin math (which could be wrong) shows those power densities are almost double that of even state of the art jet engines like LEAP. Which just leaves the fuel aspect. SOFCs, due to their high operating temperatures, allow for a lot of fuel flexibility. Technically, they could still use regular jet fuel. While that wouldn't get rid of the fossil fuels, the much higher efficiencies would result in significant decreases in the demand for fuel, which have additional efficiencies (It takes a lot of fuel to fly a lot of fuel). However, I wouldn't rule out hydrogen. The traditionally cited disadvantages of liquid hydrogen are significantly minimized for aviation. You don't really need heavy duty cryo tanks: planes operating at 15km altitudes are already at -50 degrees C, and the consumption rates would be higher than the evaporation bleedoff rates. When descending or ascending, temperatures are higher, but consumption rates are also higher. That means that the optimal insulation is a weight/bleedoff optimization problem, and I wouldn't be surprised if current foam insulation technologies were good enough. I've found an example of a 125kL vacuum-insulated tank that only needed a constant 390W of cooling to maintain zero boil-off [0], meaning that that rate of fuel bleedoff without cooling is <390W. That is 2-3 orders of magnitude lower than the consumption rates of jet aircraft, which gives a lot of leeway for reducing the insulation requirements. And even if it doesn't work, liquified renewable methane might still work, with its higher boiling point and higher volumetric energy density. [0] https://iopscience.iop.org/article/10.1088/1757-899X/278/1/012012/pdf https://iopscience.iop.org/article/10.1088/1757-899X/278/1/0...
- SlowRobotAhead 7y ago
  You could be entirely right about planes. But... Here is what I know! We're still largely using 1940s tech when it comes to many planes. Aside from spaceships, planes are the most likely to kill you when something goes wrong. So I think that's why they are slow move to new technology. So maybe fuel cells are the way to go. Maybe hydrogen. But, I still kind stick with the idea that if the tech was out and fully worked out today, in 40 years, there will still be planes flying around on piston drive ICE drinking refined kerosene.

darksaints 7y ago

> IDK, it seems the actual demand for oil will remain high. We’ll shift from using it in energy production and transportation to plastics, manufacturing, lubes and other refined oils, aviation which to shift to electric will need another 50 years of battery tech it seems, etc. Agreed on the uses for oil, but I think planes are a lot closer than you think, but not via batteries. Fuel cells will be what is used, IMO. All of their disadvantages that make them a terrible fit for cars are pretty much null for planes. Electric motors are reaching 15 kw/kg. SOFC designs are now reaching 2.5 kw/kg power density and > 60% efficiency. With waste heat recovery, 80% efficiency is on the horizon. All combined, my napkin math (which could be wrong) shows those power densities are almost double that of even state of the art jet engines like LEAP. Which just leaves the fuel aspect. SOFCs, due to their high operating temperatures, allow for a lot of fuel flexibility. Technically, they could still use regular jet fuel. While that wouldn't get rid of the fossil fuels, the much higher efficiencies would result in significant decreases in the demand for fuel, which have additional efficiencies (It takes a lot of fuel to fly a lot of fuel). However, I wouldn't rule out hydrogen. The traditionally cited disadvantages of liquid hydrogen are significantly minimized for aviation. You don't really need heavy duty cryo tanks: planes operating at 15km altitudes are already at -50 degrees C, and the consumption rates would be higher than the evaporation bleedoff rates. When descending or ascending, temperatures are higher, but consumption rates are also higher. That means that the optimal insulation is a weight/bleedoff optimization problem, and I wouldn't be surprised if current foam insulation technologies were good enough. I've found an example of a 125kL vacuum-insulated tank that only needed a constant 390W of cooling to maintain zero boil-off [0], meaning that that rate of fuel bleedoff without cooling is <390W. That is 2-3 orders of magnitude lower than the consumption rates of jet aircraft, which gives a lot of leeway for reducing the insulation requirements. And even if it doesn't work, liquified renewable methane might still work, with its higher boiling point and higher volumetric energy density. [0] https://iopscience.iop.org/article/10.1088/1757-899X/278/1/012012/pdf https://iopscience.iop.org/article/10.1088/1757-899X/278/1/0...

SlowRobotAhead 7y ago
You could be entirely right about planes. But... Here is what I know! We're still largely using 1940s tech when it comes to many planes. Aside from spaceships, planes are the most likely to kill you when something goes wrong. So I think that's why they are slow move to new technology. So maybe fuel cells are the way to go. Maybe hydrogen. But, I still kind stick with the idea that if the tech was out and fully worked out today, in 40 years, there will still be planes flying around on piston drive ICE drinking refined kerosene.