Archive:000/Calc:If all vehicles were electric: Difference between revisions

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(Created page with "Suppose we keep the status quo of transportation,<!--car culture--> but make all vehicles electric. This raises some basic questions: * How much electricity would we need to power all the vehicles? * How much energy would it take to manufacture vehicles - both in the short term and long term? * Which critical minerals would we need, and how much of each? * Could the minerals be recycled from vehicles at their end-of-life? ==Powering the vehicles== Electric cars are...")
 
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==Powering the vehicles==
==Powering the vehicles==
Electric cars are more energy-efficient than gas cars, but use a different ''type'' of energy, so this might seem like "comparing apples to oranges". But still we can use this fact to help make an estimate. Let's start by establishing a simple ratio:
Electric cars are more energy-efficient than gas cars, but use a different ''type'' of energy, so this might seem like "comparing apples to oranges". But still we can use this knowledge to help make an estimate. Let's start by establishing a simple ratio:


{{dp
{{dp
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|<nowiki>li_ion.charge_discharge_efficiency</nowiki>
|<nowiki>li_ion.charge_discharge_efficiency</nowiki>
|<nowiki>85%</nowiki>
|<nowiki>85%</nowiki>
|<nowiki>When you charge a lithium-ion battery, this much of the energy is stored. The rest is lost as heat.</nowiki>
|<nowiki>When you charge a lithium-ion battery, this much of the energy can be recovered. The rest is lost as heat.</nowiki>
|<nowiki>Range: 80 to 90 %</nowiki><br /><nowiki>
|<nowiki>Range: 80 to 90 %</nowiki><br />
from wikipedia; haven't found original source yet</nowiki>
}}
}}
{{calc
{{calc
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So far we've looked at ''cars'' - but what about buses, trucks, planes, ships, etc? So far, there isn't a lot of data available. So for these next estimates, we just have to assume that the ratios are ''similar enough''.
So far we've looked at ''cars'' - but what about buses, trucks, planes, ships, etc? So far, there isn't a lot of data available. For these next estimates, we just have to assume that the ratios are ''similar enough''.


We ''do'' have data on how much energy the world currently uses for ''transportation'' (which we could also break into subcategories, but we won't right now, for simplicity sake). So if we apply the ratios from above:
We ''do'' have data on how much energy the world currently uses for ''transportation'' {{p|which we could also break into subcategories, but we won't right now, for simplicity sake}}. So if we apply the ratios from above:
{{dp
{{dp
|<nowiki>transport.energy</nowiki>
|<nowiki>transport.energy</nowiki>
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|terawatts
|terawatts
}}
}}
<small>These wattage ratings would be ''power averaged over time''. Peak power could be higher, but hopefully we'd find ways to smooth that out.</small>
<small>These wattages are ''power averaged over time''. Peak power could be higher, but hopefully we'd find ways to smooth that out.</small>


And there we have a simple estimate of how much electricity we would need if all vehicles ran without fossil fuels.
And there you have it, a {{p2|simple|There are probably a lot of more precise estimates to be made at some point.}} estimate of how much electricity we would need if all vehicles ran without fossil fuels.




But we're not done, because we also need energy to ''manufacture'' the vehicles...
But we're not done, because we also need energy to ''manufacture'' the vehicles...
==Manufacturing the vehicles==
Producing batteries is energy-intensive. That's one reason why electric vehicles are more expensive. ''You can help expand this section by joining the {{talk}}.''
==Minerals==
First we have to estimate how much [[energy storage]] would be needed. Here's a very quick-and-dirty estimate:
{{dp
|ev.battery
|65.2 kWh
|Energy capacity of the average electric vehicle battery
|<cite>Useable battery capacity of full electric vehicles</cite><br />https://ev-database.org/cheatsheet/useable-battery-capacity-electric-car
}}
{{dp
|world.cars
|1.446 billion
|
|<cite>How Many Cars Are There In The World in 2022?</cite><br />https://hedgescompany.com/blog/2021/06/how-many-cars-are-there-in-the-world/
}}
{{dp
|commercial_factor
|2
|
|Without this, we'd be calculating for just personal vehicles. But we also need to factor in commercial vehicles such as buses and trucks. These vary widely in size, and data is hard to find, so for simplicity sake, we just assume that they'd add up to about the same as personal vehicles - thus doubling total energy storage needed. This assumption is based on the fact that freight trucks are a somewhat smaller share of [[energy demand scenarios|energy demand]] than passenger vehicles, but the trucks probably need a longer range.
}}
{{calc
|world.cars * ev.battery * commercial_factor
|terajoules
|vehicle_energy_storage_needed
}}
===Lithium-ion batteries===
[[Lithium-ion batteries]] are the current standard for electric cars and most small gadgets (phones, laptops, etc).
Is there enough lithium in the Earth?
{{dp
|<nowiki>li_ion.cell_voltage</nowiki>
|<nowiki>3.6 volts</nowiki>
|<nowiki>Voltage of a single lithium-ion cell.</nowiki>
|<nowiki>https://www.cei.washington.edu/education/science-of-solar/battery-technology/</nowiki><br /><nowiki>
https://www.fluxpower.com/blog/what-is-the-energy-density-of-a-lithium-ion-battery</nowiki><br /><nowiki>
It's 3.6 volts for the "cobalt type" of lithium-ion battery. Other types might have a very slightly different voltage.</nowiki>
}}
{{dp
|<nowiki>li_ion.lithium_by_energy</nowiki>
|<nowiki>0.3 grams per amp hour li_ion.cell_voltage</nowiki>
|<nowiki>To store a given amount of energy in lithium-ion batteries, this is how much lithium would be needed.</nowiki>
|<nowiki>https://batteryguy.com/kb/knowledge-base/how-to-calculate-the-lithium-content-in-a-battery/</nowiki><br /><nowiki>
The article says lithium per amp hour. We convert this to lithium per watt hour (energy), by including the cell voltage.</nowiki>
}}
{{dp
|<nowiki>lithium.reserves</nowiki>
|<nowiki>18425000 tonnes</nowiki>
|<nowiki>Lithium metal: Total global mineral reserves</nowiki>
|<nowiki>https://www.statista.com/statistics/268790/countries-with-the-largest-lithium-reserves-worldwide/</nowiki><br /><nowiki>
Added up all the countries: 9,200,000 + 4,700,000 + 1,900,000 + 1,500,000 + 750,000 + 220,000 + 95,000 + 60,000 = 18,425,000 metric tons</nowiki>
}}
{{dp
|<nowiki>li_ion.cobalt_by_energy</nowiki>
|<nowiki>20 kg per 100 kilowatt hours</nowiki>
|<nowiki>To store a given amount of energy, in lithium-ion batteries (cobalt type), this is how much cobalt would be needed.</nowiki>
|<nowiki>https://www.energy.gov/eere/vehicles/articles/reducing-reliance-cobalt-lithium-ion-batteries</nowiki>
}}
{{dp
|<nowiki>cobalt.reserves</nowiki>
|<nowiki>7.1 million tonnes</nowiki>
|<nowiki>Cobalt metal: Total global mineral reserves</nowiki>
|<nowiki>https://www.statista.com/statistics/264930/global-cobalt-reserves/</nowiki>
}}
{{calc
|vehicle_energy_storage_needed * li_ion.lithium_by_energy
|% lithium.reserves
}}
Just barely. How about cobalt?
{{calc
|vehicle_energy_storage_needed * li_ion.cobalt_by_energy
|% cobalt.reserves
}}
Not viable.
===Hydrogen fuel cells===
Platinum, an extremely rare metal, is a key component of both fuel cells & electolyzers. Scalability is unlikely.{{qn}} There might be other options that involve only more abundant materials, but with somewhat less energy efficiency. [https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=&cad=rja&uact=8&ved=2ahUKEwjT3KORkJL8AhXKnGoFHVzOARUQFnoECAwQAQ&url=https%3A%2F%2Fwww.princeton.edu%2Fnews%2F2019%2F06%2F17%2Fhydrogen-fuel-cells-mundane-materials-might-be-almost-good-pricey-platinum&usg=AOvVaw2dRNQTnW2TjonbmM1iL84Q More research is needed.]
==Recycling==
Minerals are scarce enough that [[recycling]] is absolutely crucial. ''You can help expand this section by joining the {{talk}}.''
==Conclusion==
Electric vehicles, ''in their current form'', are probably '''not''' a viable way to help stop [[climate change]]. Here are some ''other'' options worth exploring:
* Using some other type of battery, which doesn't depend so much on cobalt.
** Perhaps [[lithium-sulfur]] batteries?
** Or even [[sodium-sulfur]] batteries?
*** This wiki doesn't yet have enough information to say how viable these battery types currently are.
* Electric vehicles with '''much smaller''' battery capacity, for city driving only.
** This would be a challenge for marketers & entrepreneurs.
* [[Public transit]], especially [[trains]].
* Making neighborhoods [[walkability|walkable]].