46 ms·

> seem to be saying that renewables require improvement due to the scale of the problem. Certainly they must be competitive in terms of energy density otherwis

by aksss 6y ago

> seem to be saying that renewables require improvement due to the scale of the problem. Certainly they must be competitive in terms of energy density otherwise how can they substantially displace another energy source? Today renewable tech is not energy dense enough. > Once renewables are sufficiently cheap ..cheap in total lifecycle cost (not end user cost of panel), carbon negative and sufficiently energy dense (transportable at light weight/low volume relative to stored energy) > it's just building more of them. For all of this, please remember we're talking global scale for electricity generation (<30% of fossil fuel use today), plus transportation, and manufacturing, not just electric use at my house or even a small country. Straight cost - you mention taxes and regulation. This implies regulatory disincentives to produce and consume fossil fuels. It's relevant to note that at no time in recorded human history have humans backed off the consumption of an energy source unless a better replacement (more dense) was found. We nearly deforested the US east coast and almost killed off a whale species until coal came along and saved both (true story). Now we couldn't go back if we wanted to because civilization assumes a certain amount of energy input. Reducing it would have huge humanitarian impacts. Stabilizing it would be good, but this unfairly puts a huge burden on developing regions who would likely not tolerate it anyway. Technology improvement - Look in the graph below at where diesel is relative to a Li-Ion battery. That's the gap it needs to make up at 5% efficiency gain per year (many orders of magnitude). It's beyond optimistic to say that would be covered any time soon barring a miracle (the track record shows that Moore's law doesn't apply to solar cells and batteries). https://en.wikipedia.org/wiki/Energy_density#/media/File:Energy_density.svg https://en.wikipedia.org/wiki/Energy_density#/media/File:Ene... Even if you doubled the rate of efficiency improvements to 10% annualized, it's still an unrealistically wide gap to make up in my lifetime at least. Fundamentally, for your position to be true you have to assume a miraculous leap forward in technology. And/or you have to assume some global-scale rational decision making (or force) to reduce consumption voluntarily (or involuntarily :/), in contrast with the whole of historic human behavior regarding energy consumption. Seems like there's a lot of hope involved there.

pfdietz 6y ago
> This implies regulatory disincentives to produce and consume fossil fuels. It's relevant to note that at no time in recorded human history have humans backed off the consumption of an energy source unless a better replacement (more dense) was found. We have plenty of examples of humans forgoing technologies that turned out to have downsides. And it's a near universal truth that dire warnings were given about these restrictions, warnings that turned out to be vastly overblown. Technology does step up to the plate when market incentives are in place. > Look in the graph below at where diesel is relative to a Li-Ion battery. Li-ion batteries do not have to become as energy dense as diesel for fossil fuels to be displaced. Some applications don't require that energy density. We are already seeing battery electric buses, for example. In other cases something other than batteries can be used, for example hydrogen. In the worst case, net zero CO2 diesel can be made synthetically, using energy from renewables (and carbon from either CO2 capture or biomass; use of biomass would be limited to these edge cases.) We are already at the point technically where a great deal of fossil fuel for transportation would be displaced if transport paid the true cost of CO2 emission. > Fundamentally, for your position to be true you have to assume a miraculous leap forward in technology. No, the roadblock is not technology, it's proper carbon pricing. That is the biggest obstacle.
- aksss 6y ago
  > plenty of examples of forgoing technologies I didn't say technologies, I said energy sources. > batteries do not have to become as energy dense as diesel We need a storage mechanism that allows the energy gained from renewable sources to power things without interruption. Two examples illustrate the problem today - for renewables to power a cargo ship the battery load-out required to move that loaded container ship would materially reduce its cargo capacity because it's wasting so much space and mass on literally tons of batteries. Compare the capacity, speed, and installed power of MV Yara Birkeland (electric container ship) to the OOCL Hong Kong (diesel powered cargo ship) for an idea. Another example is Tokyo suffering a predictable 3-day cyclone every year, where 27 million people need 22 gigawatts of electricity. Imagine the battery array needed for that (with its inherent cost, maintenance, limited lifespan and acres of space in a space-constrained land). So these are two easy examples of why storage density needs to increase by orders of magnitude to meet the bar you set of 100% replacement. It won't be Li-Ion, it has to be something else, but that "something else" doesn't exist yet and the track record of an annualized 5% efficiency improvement for storage tech (which is generous but imagine even doubling it to 10%) per year won't catch up in our lifetimes. The math speaks for itself. > roadblock is not technology, it's proper carbon pricing If it were just pricing, it presumes that I have equivalent systems to implement and I just need to pay a premium for one vs the other. But that's not the case as illustrated in the examples above (and there are many, many more - airplanes, continuous smelting) where the existing energy storage tech doesn't work. So technology is an enormous roadblock. As to carbon pricing - carbon pricing regimes require world-wide cooperation. IF you can get that, it effectively means limiting fossil fuel usage, right? Otherwise why are we doing it? So limiting fossil fuel usage in a situation where there is no suitable replacement as described above, ultimately means you need to tell some guy in India that he can't have an air conditioner and some family in Africa that their agriculture development programs need to take a hit for lack of synthesized ammonia. This is a very unequal proposition. Alternatively, you can preserve that growth rate in the developing world and tell people in the developed world that they need to rewind their lifestyles in all ways (housing, vehicle mass, etc) to the early 1960's, which is when the US last had a consumption rate at the level needed to impact global warming. This is probably the preferable solution, but how tenable do you think either of these propositions really are? There are undeniable humanitarian costs - not just monetary costs - to reducing fossil fuel use today when there are no (at scale) suitable replacements.

by aksss 6y ago

pfdietz 6y ago

> This implies regulatory disincentives to produce and consume fossil fuels. It's relevant to note that at no time in recorded human history have humans backed off the consumption of an energy source unless a better replacement (more dense) was found. We have plenty of examples of humans forgoing technologies that turned out to have downsides. And it's a near universal truth that dire warnings were given about these restrictions, warnings that turned out to be vastly overblown. Technology does step up to the plate when market incentives are in place. > Look in the graph below at where diesel is relative to a Li-Ion battery. Li-ion batteries do not have to become as energy dense as diesel for fossil fuels to be displaced. Some applications don't require that energy density. We are already seeing battery electric buses, for example. In other cases something other than batteries can be used, for example hydrogen. In the worst case, net zero CO2 diesel can be made synthetically, using energy from renewables (and carbon from either CO2 capture or biomass; use of biomass would be limited to these edge cases.) We are already at the point technically where a great deal of fossil fuel for transportation would be displaced if transport paid the true cost of CO2 emission. > Fundamentally, for your position to be true you have to assume a miraculous leap forward in technology. No, the roadblock is not technology, it's proper carbon pricing. That is the biggest obstacle.

aksss 6y ago
> plenty of examples of forgoing technologies I didn't say technologies, I said energy sources. > batteries do not have to become as energy dense as diesel We need a storage mechanism that allows the energy gained from renewable sources to power things without interruption. Two examples illustrate the problem today - for renewables to power a cargo ship the battery load-out required to move that loaded container ship would materially reduce its cargo capacity because it's wasting so much space and mass on literally tons of batteries. Compare the capacity, speed, and installed power of MV Yara Birkeland (electric container ship) to the OOCL Hong Kong (diesel powered cargo ship) for an idea. Another example is Tokyo suffering a predictable 3-day cyclone every year, where 27 million people need 22 gigawatts of electricity. Imagine the battery array needed for that (with its inherent cost, maintenance, limited lifespan and acres of space in a space-constrained land). So these are two easy examples of why storage density needs to increase by orders of magnitude to meet the bar you set of 100% replacement. It won't be Li-Ion, it has to be something else, but that "something else" doesn't exist yet and the track record of an annualized 5% efficiency improvement for storage tech (which is generous but imagine even doubling it to 10%) per year won't catch up in our lifetimes. The math speaks for itself. > roadblock is not technology, it's proper carbon pricing If it were just pricing, it presumes that I have equivalent systems to implement and I just need to pay a premium for one vs the other. But that's not the case as illustrated in the examples above (and there are many, many more - airplanes, continuous smelting) where the existing energy storage tech doesn't work. So technology is an enormous roadblock. As to carbon pricing - carbon pricing regimes require world-wide cooperation. IF you can get that, it effectively means limiting fossil fuel usage, right? Otherwise why are we doing it? So limiting fossil fuel usage in a situation where there is no suitable replacement as described above, ultimately means you need to tell some guy in India that he can't have an air conditioner and some family in Africa that their agriculture development programs need to take a hit for lack of synthesized ammonia. This is a very unequal proposition. Alternatively, you can preserve that growth rate in the developing world and tell people in the developed world that they need to rewind their lifestyles in all ways (housing, vehicle mass, etc) to the early 1960's, which is when the US last had a consumption rate at the level needed to impact global warming. This is probably the preferable solution, but how tenable do you think either of these propositions really are? There are undeniable humanitarian costs - not just monetary costs - to reducing fossil fuel use today when there are no (at scale) suitable replacements.