11 ms·
So 26.10pounds * (1.26 dollar/1pound) / (64kWh * 0.8)... that's $0.63/kWh. At EPA specified 33.7kWh equivalent per gallon of gas, that'd be 21.56$/"gallon" of
by rektide 4y ago
So 26.10pounds * (1.26 dollar/1pound) / (64kWh * 0.8)... that's $0.63/kWh.
At EPA specified 33.7kWh equivalent per gallon of gas, that'd be 21.56$/"gallon" of electricity. On average!
Yikes. We direly need to invest in scaling up environmentally friendly energy generation, in delivering it.
I don't have huge sympathy for drivers per se, but civilization needs energy, and we haven't invested enough effort into scaling out alternative energy.
- rootusrootus 4y ago> At EPA specified 33.7kWh per gallon, that'd be 21.56$/"gallon" of electricity. That's such a roundabout way of saying "fast charging in the UK costs the same as gasoline in the US"
- isaacg 4y agoUS average gas price is currently $4.60/gallon. UK average gas price is currently $7.99/gallon. Depends on how much more efficient the electric car is than the gas-powered car.
- cameldrv 4y agoElectric cars are usually about 4x as efficient as ICE in terms of energy input -> propulsive energy[1], so it's more like $5.50/gallon, but still pretty expensive. [1] http://www.afteroilev.com/Pub/EFF_Tank_to_Wheel.pdf http://www.afteroilev.com/Pub/EFF_Tank_to_Wheel.pdf
- clysm 4y agoWhile EVs are much more efficient, you don't factor in vehicle efficiency when calculating $/eGallon. $20/eGallon is huge. My cost at home to charge is $4.10/eGallon, regardless of the efficiency of the car using it.
- cameldrv 4y agoSure. However, IMO it's more useful to look at it from this standpoint: Most usage of energy has to go through a thermal->mechanical energy conversion step. Carnot efficiency practically limits this to 20-60% efficiency or so. In general, the smaller the engine, the worse the efficiency. If your energy input is electricity, this conversion has already happened at the power plant. If your energy input is gasoline, it happens in the car. It's sort of like comparing your salary pre-tax vs. post-tax if the tax rate is 70%. There's a big difference. Most of the other energy conversions like electrical->mechanical, mechanical->electrical, electrical->battery or battery->electrical can be done at 90%+ efficiency.
- rektide 4y agoI pity the consumer that ignores how efficient their vehicle is to justify paying 3x as much for energy. I think this is intensely backwards & wrong a way to look at it. In my view, all EV chargers should be mandated to express a $/"gallon" equivalent on them. So consumers know the real actual physical reality truth of the situation. Hiding this, making EV buyers unaware of their own efficiency, is making the market blind. The market should be aware of the truth. Edit: your EV should also make it clear that it has 2-3 gallons of capacity. Because it's awesome & the future & we should all do it. But that doesn't change the fact that the dude in the F250 over there is paying 1/4th as much for the same energy you're getting, and that matters and should be seen.
- lupire 4y ago33.7kWh/gal is for MPGe, which is a measure of energy content, but it ignores efficiency of converting every into motion.
- rektide 4y agoThat doesn't matter. Consumers should measure & compare how much we pay for the energy we input to our systems.
- erik_seaberg 4y agoIf global warming is the reason we care, CO₂ per passenger-mile (km, whatever) is what we should minimize. This includes the advantages of electric motors and nuclear power and transit and the disadvantages of coal power and low transit utilization.
- rektide 4y agoPeople won't be able to appreciate how much CO2 they're saving if they just see they're paying 1/2 as much at the pump. If, on the other hand, we show people that their whole fillup is 2 "gallons" of electricity, then suddenly it's crystal clear how awesomely energy efficient your vehicle is. Looking only at work obfuscates vehicular performance. It ends up compounding a bunch of different factors. If we just told people how much energy- how many "gallons" of electricity- are going into their car, they'd understand much better. It'd be up to them to find out how polluting their grid energy was. But it should be much more efficient than the gas car, which still has yet to do most of it's energy conversion & is about to throw 66%+ of the energy input away to heat.
- vimwizard 4y ago>I don't have huge sympathy for drivers per se Must be nice living in a major city
- potatolicious 4y agoIs a "synthetic gallon" unit really the right thing to measure here? It seems like $ per distance traveled is more appropriate. At $0.63/kWh, assuming a car like the Mustang Mach-E - it'd cost $44.10 to "fill up" the 70 kWh battery. That gets you ~250mi of range, for ~$0.18 per mile. For comparison to ICE cars - take a similarly-sized crossover like the Toyota RAV-4 which gets ~27 mpg. At current gas prices in my area of ~$4.50/gallon that works out to about $0.17 per mile. In the UK the petrol option is considerably more expensive: at ~$8/gallon the ICE option is closer to $0.30 per mile. So the fast-charge EV option is either tied (by US prices) or significantly better (by UK prices) than the ICE option? It's certainly a far cry from the $21.56 equivalent measure you've got. Obviously the math changes somewhat depending on what your benchmark EV/ICE cars are, but at first glance this doesn't actually seem like a bad deal. It's certainly a far cry from the >$20 "gallon" measure. [edit] I was inspired to do the math on what the non fast-charging option would look like based on household electricity prices in my area. At $0.13/kWh the Mustang Mach-E would run about $0.037 per mile. Wow. Even in a state with much higher electric prices (say MA, at $0.24/kWh) that'd still work out only to ~$0.07/mile. Really hard to beat that for gas prices.
- reducesuffering 4y agoProblem is that EV (at least in CA) has huge upfront opportunity cost, depreciation, $500/yr registration, and hefty insurance cost because it’s a $40-$50k car. It’s going to take a lot of ~$0.10 miles (like 50k/yr?) for a $170/yr registration, $25/mth insurance 10 year old Prius to cost as much as an EV. Granted: new vs. used car, and used EV will become cost efficient in a few more years.
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- rektide 4y ago> Is a "synthetic gallon" unit really the right thing to measure here? It seems like $ per distance traveled is more appropriate. I think the value of the MPGe equivalent is glaringly overwhelming, in that it provides a real, truthful, honest & physical equivalency that can grounds understanding & give us a common scale to measure with. We should absolutely think about filling up with electricity in an equivalent way to thinking about gallons of gas. That most electric cars only have ~3 gallons is a feature of them being so efficient. But when a gallon costs as much as it does, that should also be visible and notable. I don't want consumers having two totally decoupled notions of usage. There needs to be some way to think-laterally across electric & gas cars. Being able to understand that gas prices are way lower than electricity prices- as they are- should set off alarm bells. Justifiably. Energy is God's Honest truth. Value is imaginary, a far far downstream happenstance of infinite cofactors. The gallon-of-gas equivalent is absolutely a brilliant move, grounds us to something truthful, & is how we should think of things. Shout out (again[1]) to the Technocracy Movement, which in 1937 proposed an Energy Distribution Card[2], to represent energy consumption embodied in the products & items & work of the world around us. Having a science-oriented, grounded frame of reference to begin to approach reality from is a win, is an opportunity to get humanity thinking straight, able to actually understand a complicated world, simply. Because it's true & honest & real. Only when things are comparable are they real. Money hides, not enlightens the impacts & comparability. Edit: it's been slow for me to accept, but I realize the truth might dissuade people from considering EVs, based off the $/"gallon" idea. I guess I'd say it's important to emphasize the reciprocal end as well: that their 68kW car only has 2 gallons of "gas" capacity. (That's where all the people up-talking MPGe/efficiency circle back around into being right!) Still, I think the uniform scale is incredibly important, makes real something we otherwise could never understand- it emphasizes how massively more efficient E's are. But the prices also could dissuade. But I don't want to dissuade people. Electric cars are awesome. But we need a ground-truth to compare across. [1] https://news.ycombinator.com/item?id=31525240 https://news.ycombinator.com/item?id=31525240 [2] https://www.technocracyinc.org/the-energy-distribution-card/ https://www.technocracyinc.org/the-energy-distribution-card/
- ajross 4y ago> At EPA specified 33.7kWh equivalent per gallon of gas As others are pointing out, this analysis is assuming that the EV and the ICE vehicle are using the same amount of input energy to travel the same distances, and that's not true at all. A median EV is 2-3x as efficient by this measure, because even a cheap motor gets you to 90+% efficiency, where even a well-tuned piston engine running in its sweet spot is going to be around 30-40% due to thermodynamic losses. Basically: car exhaust is really hot, that's all waste energy, and EVs don't have exhaust.
- rektide 4y agoJust the same as all these others also being wrong, that doesn't matter. Why should you a consumer think in any other terms? Why are gas users getting energy at 1/3rd the price you are? It's wrong-headed to factor in your own efficient usage against yourself. It's idiotic in extreme. There's a physical real truth about the price of energy you are getting: spinning any other yarn to consumer is just that: fakery & deception. People need to stop proposing anti-truthfulness.
- ajross 4y ago> Why should you a consumer think in any other terms? Why are gas users getting energy at 1/3rd the price you are? What is "energy" then? Are you trying to compare effectiveness of EVs vs. combustion engines as... building heat? No engine exists under the laws of physics to deliver useful work with that "energy" you're getting cheaply in gasoline. That's a ridiculous point. You buy gas, just like you buy electricity, to move your car. So measure the motion, not the heat.
- rektide 4y ago> What is "energy" then? Do we really need to regress to 7th grade science class? Go read wikipedia if you need to[1]. > Are you trying to compare effectiveness of EVs vs. combustion engines as I'm trying to prevent energy-efficiency from being bundled into the cost of energy. I'm trying to make the price of energy explicit & directly comparable, because it is & it should be, & is a ground truth provided by physics and science that is directly comparable. By doing so, I'm hoping consumers realize just how remarkably efficient EVs are > No engine exists under the laws of physics to deliver useful work with that "energy" you're getting cheaply in gasoline. This truth does nothing to convince me that we should remain oblivious to the comparative efficiencies of our systems. Knowing how much energy we put in, and seeing how far it gets us: that is the real truth, that is how we understand our impact in the world. It also is useful for helping us assess & appraise the energy we get: knowing the price/kWh is directly comparable, tells us how comparatively & competitively well our energy delivery pipelines are doing, which is yet more important & vital information to understand. Trying to bundle all the factors together breeds naught but stupidity & ignorance. Highly dislike. No one learns anything without shared frames of reference. Energy is the common frame physics provide. Science lets us celebrate & appreciate the gains (& let's us also understand weaknesses we ought improve on too). [1] https://en.wikipedia.org/wiki/Energy https://en.wikipedia.org/wiki/Energy
- stefan_ 4y agoFast charging stations are a rare convenience service, they are not offered at the cost of the energy input. Neither, of course, is gas - just the energy going into refining that stuff could move an EV far.
- rektide 4y agoThis seems like a genuine and honest & truthful & scientific assessment. It was at +2 briefly but is now, 59 minutes in, at -2. It's insane to me that truth is so heavily downvoted. What in the frak do you people have to object to? Are ya'll thinking I'm anti EV? Anything but. The reciprocal measure is that your EV should also count "gallons" of gas. That your car only has 2, 3 gallons of gas should make it clear what a wonderful contribution EV drivers are making to the world. Truth & physical reality are wonderful. Don't be afraid. It feels so vicious, the bitter bitter absurd downvoting! I don't get it. Can we please find sanity, by accepting physical reality & science in to how we think about things? I wish I had some idea why truth was so objected against, but the protests here are just so pitifully wronghearted.
- pornel 4y agoThat's a weird way to calculate it. From an EV perspective it sounds like calculating fuel cost in bales of hay :) In the UK such comparisons are typically done in pence per mile. EV efficiency varies, but it's typically somewhere between 3-4mi/kWh. At 57p per kWh (the current InstaVolt rate) DC fast charging is 14p-19p per mile. At UK's current 170p/l petrol price, to pay 14p-19p per mile, you need an ICE car with 34-46mpg. Home charging is about 20p per kWh, which is roughly 6p per mile. An ICE car with equivalent per-mile cost would need to have over 100mpg. People who are lucky to have a fixed-price tariff with off-peak rates can still get 2.5p/mile.
- rektide 4y agoWhy would you factor your own efficiency against yourself? Why would you voluntarily ignore the fact that you are paying 4x more than the person filling up in petrol? > That's a weird way to calculate it. Why? Why would you ignore that you are paying 4x as much for the same energy? Why would you count your own energy-efficiency against yourself at the pump? EV owners should be proud. They should take pride that their vehicle goes so far on 2 "gallons" of electricity. But the world should also face that gas prices are absurdly stupidly cheap, and that we are bad at electricity still, that electricity coming from the grid & through a charger is preposterously expensive. We should optimize & work on this, but right now we can't even see what a glaring absurdity it is that charging prices are so absurdly stupid high. Having a uniform way to compare energy usage makes all the sense.
- pornel 4y agoEV puts almost all of its energy into moving the car, while ICE loses majority of the energy to heat. ICE is simply incapable of using most of the energy contained in gasoline (you'd need to have a steam turbine or such). The efficiency difference is so dramatic, that it makes up for the price difference. A unit of energy for an EV may be much more expensive, but it also makes it go farther. Utility of cars is in movement, not in being an energy sink, so it makes more sense comparing directly based on utility rather than the energy they burn.
- 4y ago