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> What's the environmenal impact of a hydrogen fuel cell versus a rechargeable battery with a comparable range? Battery-electric vehicles are about 2-3 times m

> What's the environmenal impact of a hydrogen fuel cell versus a rechargeable battery with a comparable range? Battery-electric vehicles are about 2-3 times more energy efficient than hydrogen fuel cell vehicles, according to VW [0] > Doesn't making a battery require mining a ton of metals? Less, actually - a bit under half a tonne of metal in a Tesla battery pack, most of it nickle (as of 5 years ago) [1] > How efficient is the recycling of spent batteries? Roughly 92% [2] and improving. A car purchased today would have its battery recycled in ~10 years, so it'll be higher by then. [0] https://insideevs.com/news/406676/battery-electric-hydrogen-fuel-cell-efficiency-comparison/ https://insideevs.com/news/406676/battery-electric-hydrogen-... [1] https://electrek.co/2016/11/01/breakdown-raw-materials-tesla-batteries-possible-bottleneck/ https://electrek.co/2016/11/01/breakdown-raw-materials-tesla... [2] https://electrek.co/2021/08/09/tesla-battery-cell-material-recovery-new-recycling-process/ https://electrek.co/2021/08/09/tesla-battery-cell-material-r...

Youden 5y ago
My point was that the environmental impact encompasses more than just the energy usage. What I wanted to get at with my questions was "what's the ratio of bad stuff produced per kilometer driven for hydrogen and for batteries?" How much more mining is needed to produce a battery pack than a fuel cell? How much more waste metal is there? Are there any chemical pollutants in either system? Both systems are going to have different ratios between Bad Stuff and efficiency and my unqualified guess is that hydrogen _might_ be better.
- SECProto 5y ago
  > What I wanted to get at with my questions was "what's the ratio of bad stuff produced per kilometer driven for hydrogen and for batteries?" Right. When comparing objects of similar complexity, cost of the object is generally pretty proportional to bad-stuff-produced, with exceptions for unpriced externalities (carbon emissions being a big one, and mining or refining in low-responsibility jurisdictions being another). The carbon emissions of battery pack manufacturing are small[1] relative to lifetime emissions from an ICE car, not totally sure for FCEV. > Both systems are going to have different ratios between Bad Stuff and efficiency and my unqualified guess is that hydrogen _might_ be better. I couldn't find anything specific to FCEV, but my gut instinct is that FCEV would be dramatically worse - hydrogen is reformed from natural gas, necessarily entailing carbon emissions. If you're going to release the CO2 from natural gas anyway, might as well do it by burning in a high-efficiency turbine and use the energy to charge your BEV at high end-to-end efficiency. Or if you're going to consider "green" hydrogen, might as well use the renewable energy to directly charge a battery, at 3x higher efficiency. [1] https://theicct.org/sites/default/files/publications/EV-life-cycle-GHG_ICCT-Briefing_09022018_vF.pdf https://theicct.org/sites/default/files/publications/EV-life...

Youden 5y ago

My point was that the environmental impact encompasses more than just the energy usage. What I wanted to get at with my questions was "what's the ratio of bad stuff produced per kilometer driven for hydrogen and for batteries?" How much more mining is needed to produce a battery pack than a fuel cell? How much more waste metal is there? Are there any chemical pollutants in either system? Both systems are going to have different ratios between Bad Stuff and efficiency and my unqualified guess is that hydrogen _might_ be better.

SECProto 5y ago
> What I wanted to get at with my questions was "what's the ratio of bad stuff produced per kilometer driven for hydrogen and for batteries?" Right. When comparing objects of similar complexity, cost of the object is generally pretty proportional to bad-stuff-produced, with exceptions for unpriced externalities (carbon emissions being a big one, and mining or refining in low-responsibility jurisdictions being another). The carbon emissions of battery pack manufacturing are small[1] relative to lifetime emissions from an ICE car, not totally sure for FCEV. > Both systems are going to have different ratios between Bad Stuff and efficiency and my unqualified guess is that hydrogen _might_ be better. I couldn't find anything specific to FCEV, but my gut instinct is that FCEV would be dramatically worse - hydrogen is reformed from natural gas, necessarily entailing carbon emissions. If you're going to release the CO2 from natural gas anyway, might as well do it by burning in a high-efficiency turbine and use the energy to charge your BEV at high end-to-end efficiency. Or if you're going to consider "green" hydrogen, might as well use the renewable energy to directly charge a battery, at 3x higher efficiency. [1] https://theicct.org/sites/default/files/publications/EV-life-cycle-GHG_ICCT-Briefing_09022018_vF.pdf https://theicct.org/sites/default/files/publications/EV-life...