Yesterday I just sent my buddy picture with energy generation in Germany. 32,8% coal!!! So the future will be burning coal to power emission-fee cars. It’s just shocking nonsense as I see it as an engineer.
I saw a video in YT where in a state like Utah in the US an ev becomes greener after the equivalent of few tens of gas tanks (don't remember the number). Will try to find out the sources.
> Switching to electric just because of that is worth in the long term
Is it, though?
Batteries are not exactly environment-friendly and hydrogen seems too often ignored.
I am not an expert so probably don't know many issues but on the face of it hydrogen seems much less disruptive than batteries.
Also, it is a bit easy to claim that we need to rush and have the luxury to make bad decisions. We have had decades and still have decades, and cannot change the whole infrastructure again in 10-20 years...
Batteries have downsides but apart from them, they do work.
Hydrogen can either be stored cryogenically (which is problematic in a car), or compressed. In the latter case, hydrogen leaks out through the metal (because its atoms are so small) and worse still, causes embrittlement of the metal.
So while we know how to build a battery car today, which is safe and stable, it's much less the case for hydrogen. It's not like you can take eg LNG car tech and just fill it with hydrogen.
The well-to-wheels analysis for an EV powered by a largely fossil-fuelled power grid is not good. Transmission and battery losses wipe out most of the (quite small) gains.
>a state like Utah in the US an ev becomes greener after the equivalent of few tens of gas tanks
Would love to see the source for that. Last time I checked, with a relatively "green" grid (something that almost everywhere in the US is a long way from achieving), the CO2 crossover point for an EV is at 20,000+ miles.
Batteries are expensive and motors are dirt cheap, so the only EVs with decent range are super high end, performance, luxury models.
Compared to a 500hp luxury SUV they're great.
Compared to an econobox they use about the same amount of energy per km.
They're up if you compare whole system emissions for the car vs. Emissions at a ff plant.
If you add in the fugitive methane or horror show that is coal mining and ash they're on par again.
The sleight of hand is in the definition of "emissions".
If you mean CO2 - then no, not really. If you are powering your EV with a fossil-fuel powered grid, then the transmission and battery losses make up for the small gain in power plant efficiency over an ICE (as I already said). The CO2 argument for an EV only works when the grid has a substantial "green generation" component.
If you mean "emissions that are immediately bad for people" - it depends who you are talking about. EVs replace tailpipe emissions at the point of use with centralised emissions, both at the point of manufacture, and at the point of charging power generation (which will most likely be in a Western country with well-controlled emissions). As a cyclist, I have to admit it's nice not to breathe in tailpipe fumes. I try not to worry too much about all the damage being done by EV manufacture far far away from me.
EVs waste a lot less power than ICEs after the motor. Much of it not for any reason that couldn't be true of an ICE as well except for design priorities.
200Wh/km of wall socket power is about 60MJ per 100km. If that came from coal in a modern-ish plant it's about 10-15kg of CO2. From gas it's around 5-8kg.
A highly efficient ICE produces 50gCO2e per km or 5kg for the same distance. This looks good until you consider that's not where the supply chain ends. Producing that petrol took another 3kg, or maybe 5kg if it was tar sands. A mostly-ff mix EV starts to look good here.
But it's also not end of the line for the gas plant. Fugitive methane will double its GHG output. Coal has NOx and some deleterious effects that aren't precisely GHG but are just as bad.
So the tesla produces more than the econobox. But an 'equivalent' once you game the metrics and compare against a Porsche Cayanne produces more than the tesla.
Really to reduce emissions quickly in urban or suburban areas we need more vehicles that look like a Zev, an Aptera, suzuki samba, a golf cart or a bicycle etc. and fewer that resemble a tesla or a monster truck (as well as more rail based vehicles).
I'm talking about electrical transmission losses. The worst-case is for high-current, domestic loads, where about 15% of the power from the electrical power generator is lost. Add in another approx. 15% for charging and discharging the EV battery, and it's not so good.
>200Wh/km of wall socket power is about 60MJ per 100km
You forgot the above losses.
>A mostly-ff mix EV starts to look good here.
Not at all. By your (very optimistic) calculations, they are about the same. You'll never pay off the CO2 debt of manufacturing the EV battery, let alone start averting the climate catastrophe!
>Really to reduce emissions quickly in urban or suburban areas we need more vehicles that look like a Zev, an Aptera, suzuki samba, a golf cart or a bicycle etc. and fewer that resemble a tesla or a monster truck (as well as more rail based vehicles).
Very true. Weird that all of the currently-pushed solutions involve large and expensive EVs that barely do any good.
200Wh is about a 20% estimation-factor on top of the commonly claimed 160Wh/km for a tesla. This accounts for any losses from charger to battery. Losses past that point are irrelevant because the point of measurement is battery drain per km. Differences between the test protocol and real world should be mirrored in the econobox stats. Emissions figures were commonly quoted per kWh at the wall socket.
> Not at all. By your (very optimistic) calculations, they are about the same. You'll never pay off the CO2 debt of manufacturing the EV battery, let alone start averting the climate catastrophe!
Precisely my point? I'm asserting that a city-car econobox has better marginal per km emissions than a luxury sports EV. A cayanne will have about 4-6x the emissions as the econobox and that comparison will favour the tesla. Also please do point out where they were optimistic -- there are very few ICEs that get 50g/km?
EV makers play sleight of hand by eliminating the segment of small light cars that can get you two cities over, then claiming their replacement in the form of a luxury performance car is 'better' by comparing it to luxury performance SUVs.
> Not at all. By your (very optimistic) calculations, they are about the same. You'll never pay off the CO2 debt of manufacturing the EV battery, let alone start averting the climate catastrophe!
This isn't as much as you think, most of the industry isn't using NMC anymore and there's less of the expensive materials per cell even compared to earlier LFP variants. If you're not insisting on obscene power densities and range you'll never use then 30kWh of LFP batteries has GHG impact commensurable with a few thousand km of usage of either the econobox or the coal powered luxury EV -- it doesn't take much to tip the balance. Similarly you can use motors without scarce metals.
> Very true. Weird that all of the currently-pushed solutions involve large and expensive EVs that barely do any good.
Because EVs are here to save the car industry not the planet. Although they do have one positive externality: a bunch of people willing to pay $500-1000/kWh allowed for the development of the battery industry where doing it to reduce emissions would have never happened.
Yep, agree with all of that.
>Because EVs are here to save the car industry not the planet.
Especially this.
I've already made the point that EVs are almost like Rai Stones - an immobile indicator of wealth.
That's probably a bit too far. The range issues are very much overblown edge cases. If you're going to make a new personal vehicle it should probably run primarily on a small LFP battery -- whether pure plug in or hybrid.
Modern cars in general are ridiculous, anti-practical conspicuous-consumption symbols of just how much power the owner has to ruin the lives of those around them. EVs are not much different in that regard.
So like a Rai Stone?
>it should probably run primarily on a small LFP battery -- whether pure plug in or hybrid.
If you go down that route, you'll probably work out that people should be riding e-cargo bikes everywhere (I've been tempted myself)
> If you go down that route, you'll probably work out that people should be riding e-cargo bikes everywhere (I've been tempted myself)
They're great. Mine has a solar panel over the cargo bed and never needs charging (literally do not own an AC charger for it). You need some minimal level of concession from driving culture and infrastructure to make them survivable though. They also don't cover all use cases (but carrying the *%#$ full sheet of plywood that is always brought up as somehow being an essential daily staple is quite possible with a variety of designs or trailers).
Interesting - what's your average daily mileage? I'm relatively familiar with the power requirements of EVs, and large-scale solar installations. I have no idea what kind of average charging power a small solar panel provides!
It's a nominal 200W panel (older fairly inefficient monocrystalline, big enough for a small sunshade which is its main function) and will fill the 1.1kWh battery in about a day (in a near-optimal climate), or two if the weather is meh. Before I mounted it on the trike I could get ~100-150km before plugging it into the panel on flatter ground or about 20-30km on a route with several big hills (12% grade) and a heavy (50kg bike + 50-100kg cargo + 75kg rider) load.
The trike is pretty speed limited by handling though (20-25km/h) and it takes very little effort on the flat to keep it above the 25km/h speed limiter. On flat ground or shallow hills (1-2%) during the sunny part of the day (9-3) I can't use more power than the panel provides without going up hills because of the speed restriction.
I'd imagine on a bakfiets in an area where 32km/h limiters were allowed you'd get about 30-50km depending on the terrain.
Some back of the envelope:
Consider this: https://www.bakfiets.com/elektrische-bakfiets/cargobike-clas...
A less ghetto lid than my arrangement would be 0.63m^2
This would fit okay as a lid: https://www.solar4rvs.com.au/sunman-earc-100w-flexible-solar...
a little narrow and would hang over the edge a little.
Assume it's about 45 degrees from optimal (70%) and that you're getting the average irradiance from somewhere like denmark (1000kWh/yr). You'll get about 71kWh/yr. Cut off 7kWh for charging loss so 62kWh.
A typical bike battery is 500Wh, so 120 charges or 1 full charge every 3 days.
A charge might get you 20km or it might get you 90km, but for a typical rider with moderate hills who puts in a 40-60W contribution (same effort as walking) and doesn't want to risk grinding home the last 10km on a cloudy day, a reasonable ballpark is 50km/day. So you're looking at ~15-20km (but you'll need to charge it in winter), or maybe up to 5x that (and decent range even in winter) if you think very carefully about parking, live in a better climate for solar, and do 25 rather than 32.
It's a nominal 200W panel (older fairly inefficient by new standards monocrystalline, big enough for a small sunshade which is its main function) and will fill the 1.1kWh battery in about a day (in a good climate of 1800kWh/yr), or two if the weather is meh. Before I mounted it on the trike I could get ~100-150km before plugging it into the panel on flatter ground or about 20-30km on a route with several big hills (12% grade) and a heavy (50kg bike + 50-100kg cargo + 75kg rider) load.
The trike is pretty speed limited by handling though (20-25km/h) and it takes very little effort on the flat to keep it above the 25km/h speed limiter. On flat ground or shallow hills (1-2%) during the sunny part of the day (9-3) I can't use more power than the panel provides without going up hills because of the speed restriction (ie. It gains charge).
I'd imagine on a bakfiets in an area where 32km/h limiters were allowed you'd get about 30-50km depending on the terrain.
Some back of the envelope:
Consider this: https://www.bakfiets.com/elektrische-bakfiets/cargobike-clas...
A less ghetto lid than my arrangement would be 0.63m^2 or up to 150W nominal if it was a perfect fit and a high end panel.
This would fit okay as a lid: https://www.solar4rvs.com.au/sunman-earc-100w-flexible-solar...
a little narrow and would hang over the edge a little, not far offour benchmark.
Assume it's about 45 degrees from optimal (70%) and that you're getting the average irradiance from somewhere like denmark on a meh week (1000kWh/yr) where you only think carefully about your parking spot at home. You'll get about 71kWh/yr. Cut off 7kWh for charging loss so 62kWh.
A typical bike battery is 500Wh, so 120 charges or 1 full charge every 3 days.
A charge might get you 20km or it might get you 90km, but for a typical rider with moderate hills who puts in a 40-60W contribution (same effort as walking) and doesn't want to risk grinding home the last 10km on a cloudy day, a reasonable ballpark is 50km/charge. So you're looking at ~15-20km/day (but you'll need to charge it in winter every week or so), or maybe up to 5x that (and decent range even in winter) if you think very carefully about parking, live in a better climate for solar, and do 25 rather than 32.
Start burning coal
Pretend that nuclear waste from coal released uncontrollably from chimneys and ash dumps does not exists.
In the meantime renewables, especially wind have been growing rapidly and have accounted for more than 50% of all electricity generation in 2020. In 2021 Wind alone was nearly a quarter of the whole electricity production.
There are plenty other methods to store energy but most involve gravity. Batteries can be used for small scale rapid reactions to changes in demand or production. Actually fully switching to EVs as a side effect can create a distributed system of energy storage.