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Comment by kylec | Hacker News Reader

I was talking to my father a few weeks ago about electric cars, and I wanted to quantify how much going electric would save him so I ran some numbers. Where he lives gas is currently somewhere around $2.20/gallon. His car gets around 30mpg combined, so he's paying ~$0.073/mile.

Tesla's website contains a "charging estimator" for the Model S, which estimates a cost of $12.04 for a total charge of 300 miles in a 90D. In the fine print, they state that the calculation is based off of the assumption of $0.12/kWh cost for electricity, which works out to a total of 100kWh to fully charge a 90D to 300 miles of range. However, he pays far more than $0.12/kWh - he actually pays $0.22/kWh. This means that the fuel cost of the Model S for him is exactly the same: ~$0.073/mile.

I write this to say that I had always assumed that electricity was far cheaper than gasoline, and I was surprised when I ran the numbers and saw that it wasn't. It seems that articles like this assume that of course people will switch to electric cars in droves once the cars get cheap enough and the range is good enough, but unless electricity becomes cheaper or gas becomes more expensive, many people, like my father, will choose to continue to drive gas-powered cars.

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Bigger issue seems to be people overestimate how much they spend on fuel. You buy the car once, but you refuel it hundreds of times over its lifetime, giving the impression that fuel is a big expense.

For example, if you assume $0.073/mile, for 100,000 miles, that is $7300. If going electric cuts that in half, you save only $3650, which is only ~10% of the cost of the vehicle.

Looking at total cost of ownership (car + maintenance + fuel) makes much more sense than just fuel.

It's even worse than that, because eventually the battery pack will have to be replaced.

While Tesla may cover that under some warranties, people who bought something like a Nissan Leaf are SOL. Their cars start losing range much quicker than a Tesla, because of the need to charge almost daily due to lower range.

Google shows the replacement cost for a Nissan Leaf battery at $5,500. Going by your calculations for 100k miles (which is Nissan Leaf's warranty range for the battery), the electricity cost will have to be $1,800 for it to make sense to buy. That's going to be nearly impossible to achieve.

The math starts to become a bit better at $4/gallon, though.

Does that replacement cost for the Leaf battery include the core credit for returning the old battery? Those batteries still have value, and if they can be re-manufactured or re-purposed as stationary storage batteries, that could reduce the cost significantly.

How much is this credit?

Depends on how much the old battery is worth. It's like replacing your transmission in an ICE. When you replace your transmission, you get a rebuilt one for like $1k. The actual price for a transmission is like $2, but if you send them the broken one from your car to rebuild for the next car, you get a Core credit.

I did a similar calculation (CA power is wayy expensive). There are additional considerations however, which is 'overhead gas' (or gas spent going to and from the gas station) not a lot but its something you don't buy if you charge at home, and "price fluctuations", buying gas has literally gone from $2 to nearly $5 back to nearly $2 over 5 years. My electricity has gone up slightly over those same 5 years. From a "predictive" point of view, it helps that it doesn't fluctuate as much.

Under the category of 'hacks' is the story of the guy who uses heating oil from the house boiler to run a generator which charges his electric car. Heating oil is generally sold without any of the associated gas taxes and so cheaper per gallon than #2 diesel at the pump.

I guess it makes a lot more sense to own an electric car in Europe, where gasoline prices are around 1,50 euro per liter, or $6,50/gallon, while electricity prices are around $0.20/kWh.

Still, recharging an electric car is still a lot more inconvenient than refueling a normal car.

Only on road trips or if you have an extremely long commute. The vast majority of the time with an electric car it's much more convenient because you charge overnight. You never have to go to a gas station again.

Taken to its logical conclusion (a hired fleet model for cars rather than individual ownership), the charging becomes someone else's problem and they get to leverage economies of scale that you as an individual wouldn't.

I think it makes a lot more sense to switch to electric car right now. But taxes contribute to more than 50% of the retail gas prices in Europe. So what would happen when majority of drivers switch to electric cars? How european governments will recoup lost tax revenue?

But the tax difference is just temporary - if EV's become popular - charging will be taxed too.

I think it would be impossible to tax charging (how would you know if someone is charging off the grid via solar?), but you could probably institute some sort of per-mile charge when renewing the car registration.

I disagree. Fuel is only one part of a car's cost. The capital expense, maintenance and insurance are other costs.

You pay a really high premium for electrics. If you insist on buying a new car, the TCO of a Honda Fit or similar car will be lower than an electric, and you avoid whatever bullshit that you need to deal with from the vendor (i.e. Using the dealer for all repairs) and dealing with charging stations and carrying the various adapters.

To wit: the 12V battery in a prius (the one that fills much the same role as the battery in a gas-only car) "repaired" at the dealer, using OEM parts, in 2016, is pushing $300

this post is from 2012, OEM battery was $235 at the time:

http://www.priusonline.com/242-prius-battery-charging/20810-...

That won't fly, once you are out of the warranty period.

Also maintenance costs are lower for electric cars.

An assertion that has yet to be proven. While an electric car has fewer moving parts to wear out, those parts that do need maintenance are going to be specialized pieces of electronics and power distribution kit that will cost far more than a few spark plugs and a new muffler.

That's not really true. The OP claimed that the maintenance costs are lower. "Specialized pieces of electronics and power distribution kit" are not involved in maintenance, those are repair parts you're talking about. Maintenance and repair are two different things: one is something you do proactively because some parts are designed for limited life and must be replaced periodically to keep the system in good running condition, whereas the other is something you do when something unforeseen breaks down. A spark plug is a maintenance item; a spark plug coil is somewhere in the middle but closer to a repair part (they do fail, but not often and usually after a very long time, they usually last the life of the car), whereas an ECU is absolutely a repair part because it should never need replacement. "Specialized pieces of electronics" also should not fail for the life of the vehicle.

Why this is important is that a car can easily have very low maintenance costs, but very high repair costs. European luxury cars (sold in the US) are a good example of this: they're very reliable these days and shouldn't be hard or expensive to service (filters don't cost that much, oil is standard), but repair costs for a BMW or Mercedes are outrageous by most accounts because factory parts are very expensive for those brands, whereas similar parts for a more pedestrian American or Japanese brand are usually much cheaper.

Many utility companies have special rate plans for EV charging. Electricity is incredibly expensive in San Francisco but PG&E has a special rate plan that is only $0.11/kWh if you charge after 11pm.

https://www.pge.com/tariffs/tm2/pdf/ELEC_SCHEDS_EV.pdf

Does the utility that serves your father have a similar EV plan?

I doubt it. I checked their website (http://www.emeramaine.com) and I couldn't find anything about a special EV rate.

It doesn't appear they have an EV-specific rate unfortunately.

Other utility companies just always offer off-peak rates to everyone, e.g. depending on time of day or season.

But of course, this is specific to your father's scenario. A quick Google search shows the average cost of electricity in the US actually is $0.12/kWh.

Of course, but I would encourage anyone that's thinking about getting an electric car to figure out what they're paying for electricity and run the numbers to understand what the cost impact is.

To add another anecdata point, I live in the San Jose area and I just checked my latest PG&E bill; It's kind of complicated because there's a weird tier system, but I paid a weighted average of $0.2095/kWh last month. However, if I were to get an electric car, the additional electricity it would use would come from the top tier, which is $0.2409/kWh. Then again, gas is ~$2.80/gallon, so electric would still be cheaper, but not by much.

If you're a heavy user (probably with an EV) you can sign up for a Time of Use rate plan, which will give you access to lower rates for off-peak charging (and higher peak rates).

Wouldn't you often charge at night, when electricity is cheaper?

$0.22/kWh is crazy high I pay under 10c/kWh, you can install solar and save a lot of money at that rate. Further, 2.2$/gallon well below average for the last 10 years, where exactly does he live?

PS: There does seem to be some serious price gouging going on. "In Sacramento, a family using 500 kilowatt hours of electricity last October was charged $58." 58/500 = 11.6cents. http://www.latimes.com/local/lanow/la-me-ln-electric-bills-d... That same 500kWh would be 47.07$ from vernon or 116.42$ from SDG&E.

Do you take into consideration the cost of installing solar and future maintenance costs in an estimate like this? Im asking honestly because Im not sure if people do?

I would, if you ignore them you can get as low as ~8 cents per kwh hour before and ~6c/kWh after incentives. But, that's ignoring battery backup for night time use. Still, beating 22c/kWh TCO is easy in most of the US and your insulated from future price hikes.

Here, around Denver, CO, I'm currently paying somewhere between $1.99 to $2.19/gallon.

Sacramento has their own utility district, "SMUD". In the neighboring counties, we have PG&E. I talked to a coworker in Sac. His highest "tier" price is about my lowest tier. Marginal cost in the upper tiers is in the 30 to 40 cent per kWh range (it has changed a bit from year to year due to some restructuring). The only people who I can see staying in Tier one would be single people who leave the house all day (with the AC off). If you have a family, fuggedaboutid.

We recently put in solar panels to at least shave the top tiers off of the bill (very cost effective vs $.35/kWh, even if not at $.12/kWh). However, I feel it's only a matter of time before PG&E lobbies for mandatory time of day based billing, in which case the panels won't help reduce the rates much for charging a car.

Sad, but true. Also, I had a used Leaf for a few days, but took it back because the battery only held about 80% of its original capacity, barely made a round trip to work (49 miles) with no A/C running, and required a special fast charge outlet to be installed if I wanted it to do a full recharge overnight. For doing short trips (say, 25 miles including some steep hills), it was great, and would recharge in about 6 hours from a standard outlet. It would have been a great car for my wife, if she could remember to plug it in when she returned from errands (not likely, alas).

I had always assumed that electricity was far cheaper than gasoline

As you note, in many places electricity is far from cheap. Also you need to amortize the cost difference of a Tesla vs a conventional car. That's hard to justify as long as a Tesla costs in the neighborhood of $100,000.

But, perhaps generate that electricity on your rooftop! The utilities have lobbied effectively to lower the feed-in prices they must pay, so it may increasingly be cheaper to use that solar power yourself. I not up on the details, but perhaps this is one argument Musk is using to support Tesla's proposed acquisition of SolarCity?

many people, like my father, will choose to continue to drive gas-powered cars

I agree with you. I don't think the article made a very good case for electrics cars. The "gadget" market isn't that large for such an expensive item.

That said, I think I'd buy something like a Tesla once the pioneers have endured all the arrows in their backs and the bugs are worked out. So maybe 2025 might be the tipping point, as the article posits?

Unfortunately, me and my car are at work when the sun is shining on my rooftop.

You could feed power into the grid to offset your charging usage at night. (Perhaps even come out ahead of where you would be charging during the day, if your power utility has lower pricing off-peak.) Alternatively you could add a home battery.

10 years from now you will have an electric car. An auto battery changing system where the batteries are charged with solar panels and changed automatically when you park your car at night all made by tesla of course. Currently the loss like battery life and power I feel are too high to make economic sense for using a home battery like powerwell charged with solar to top up your car. But swapping the batteries themselves might work.

However, a gasoline powered car also takes engine oil and transmission fluid if it's an automatic. It will also require regular servicing of the engine and eventual replacement of worn seals etc.

If the fuel cost per mile is the same the electric car could still be cheaper. I can't say how much though, because that depends on the servicing cost per year vs the battery replacement cost and that depends on your local service department.

The battery in a Tesla costs $12k-40k to replace, though it's under warranty for 8 years.

The battery decay is going to be gradual, even though noticeable in a Model S, given its huge battery, it would still be a drivable vehicle even if it loses 50% of the battery capacity. So that 14-20K expenditure will not kick in till 15 years or so with a patient owner, which is pretty much lifetime of many cars in US.

And in 15 years the batteries will inevitably be much less expensive than they are today.

And hopefully much more powerful, extending THAT purchase even further.

I wouldn't count on getting much more kWh into lithium. But the batteries probably will degrade slower in the future.

Luckily you don't need to maintain electric cars at all.

You do. But keep in mind they have way less parts, moving or otherwise. Spark plugs, cables, the entire engine cooling system, fuel pumps, all of that is missing.

It boils down to: battery (big unknown, but seem to be holding up surprisingly well), engine (incredibly simple!), no transmission or a very simple one (Nissan Leaf has a single gear), inverter, charger, brakes, and the standard 12V battery you find in all cars (which doesn't have to drive a starter motor, so should last longer).

FYI Generally an electric "engine" is referred to as a motor.

Battery cooling is also a factor that you shouldn't ignore

Wow, electirc cars are so simple it is surprising that so few companies make them! The moving parts in a car are pieces that 1) have multiple manufacturers and are relatively cheap to replace, and 2) can be replaced by a wide range of repair shops so that competition can keep a check on the overall replacement costs. What you left out of your electric car list are all of the specialized electronics and only-for-this-car equipment that are all very expensive to replace and will all only be supplied by the manufacturer. The idea that you can just go online and shop around for an inverter for your Tesla or run down to the auto parts store to pick up the right 12V battery is laughable.

False comparison. Your gas car also has specialized electronics, namely the ECU, the ABS system, the SRS system, which are all needed for the car to be operational. Good luck finding an aftermarket ECU for your car.

There's no more "only-for-this-car" equipment in an EV than in any other car; the main difference is that with so many models of gas cars made by each maker, they reuse a lot of parts between models, so there's economies of scale. In an EV future, the same would be true for EVs. You're not going to swap an axle from a Chevy into a Honda, or from a Honda Civic into a Honda Ridgeline, so even here it's limited. And you're not going to swap a door panel from a 2017 Civic into any other car at all, or from any other car into that one; those are only-for-this-car items; every car has those.

There are lots of aftermarket ECUs [1]. Usually only performance tuners buy them, but there's no reason you couldn't get one for other reasons. That said a junkyard ECU is going to be a much easier fix.

[1] https://www.google.com/search?q=aftermarket+ECU&ie=utf-8&oe=...

Your aftermarket ECU won't pass emissions tests in most places that have them, so this really doesn't exist for practical purposes. Aftermarket ECUs are for race cars.

As for the junkyard ECU, why do you think that won't be also true for EVs?

You can usually choose different maps with aftermarket ECUs, there's no reason you couldn't load one that passes emissions tests.

I've flashed my own car's stock ECU with a tuned map, but it's easy to load the original one back on.

Anyway, this is a stupid argument, I hardly think that emissions tests will be a reason you can't put an aftermarket ECU into an electric car!

>You can usually choose different maps with aftermarket ECUs, there's no reason you couldn't load one that passes emissions tests.

Will it look exactly like the factory ECU? Most emissions tests now consist of plugging in a device into the OBD-II jack and ensuring the factory emissions equipment has not been tampered with. An aftermarket ECU would fail this; it's "tampering" by definition. Emissions laws generally do no allow any deviation from factory spec or factory equipment. They don't just test the actual emissions levels, and they don't test the levels at all in many places.

>Anyway, this is a stupid argument, I hardly think that emissions tests will be a reason you can't put an aftermarket ECU into an electric car!

It is stupid, because that's not what I claimed at all. One poster claimed that EVs would be too expensive to fix because of non-standard, "only-for-this-car" electronics. I pointed out that this is already true for gasoline cars, with ECUs being an example. Then someone else jumped in and claimed that aftermarket ECUs exist, when in reality they're horribly expensive and only racecars use them, so that claim was irrelevant, and then they admitted that you can just buy a junkyard ECU cheap. I pointed out that this would also be true of EVs, which was just ignored, even though it completely invalidates the argument about EVs being expensive to fix.

Face it: every car has specialized parts, especially electronics. You can't just take an ABS module from a Nissan and slap it into a Ford. You can't take a wheel bearing from an H2 and slap it into a Prius. Parts for mass-market cars have always been available from different places: dealerships for OEM parts at high prices, aftermarket parts for popular models from parts stores, junkyard parts for everything if you can find them and are OK with them being used. This will be no different for EVs; it's stupid to think it would be. And it's also stupid that several different people jumped in here with completely incoherent arguments, all so they could bash EVs.

Yes this whole ECU thread has nothing to do with the original discussion comparing EV and gasoline vehicles wrt how easy it is to get replacement parts.

>> I hardly think that emissions tests will be a reason you can't put an aftermarket ECU into an electric car!

> It is stupid, because that's not what I claimed at all.

Yes you did:

> Your aftermarket ECU won't pass emissions tests

You brought up aftermarket ECUs not passing emissions tests, I just (incorrectly) commented that you could probably load a stock (or what I thought would be emissions-passing) map onto an aftermarket ECU because I wasn't aware about the tampering part. I naively assumed they actually tested the emissions from the car when testing it for emissions. :P

For what it's worth, I agree with you about replacement parts being specialized for all types of cars, and for the record I'd be very surprised if an aftermarket ECU ever appeared for the Tesla, given how closed and hostile to any modification (or even repairs!) they are. You can't even get a service manual if you don't live in Massachusetts, and even then you can only buy access to it on a subscription basis! [1]

In fact, at the moment I'd never even consider buying a Tesla because who knows what it's like to own one after the warranty is up? If my Tesla ECU failed, there's nothing to say it would even be possible to put a legitimate Tesla junkyard ECU in there and have it work without their blessing.

Out of curiosity, do places that have emissions testing actually keep testing cars regularly every year?

[1] https://syonyk.blogspot.com.au/2016/03/is-tesla-building-thr...

> You do. But keep in mind they have way less parts, moving or otherwise. Spark plugs, cables, the entire engine cooling system, fuel pumps, all of that is missing.

My hybrid actually has two independent liquid cooling circuits: one for the ICE, one for the electronics.

But other than that nit, I agree with your argument.

$0.22/kWh is very high. I pay like $0.09/kWh. On top of that in my LEAF I average ~4 miles per kWH, which gets me to a cost of $0.0225 per mile. Considerably cheaper than gas, even at $2.20/gallon. The last year or so has had abnormally low gas prices in the US, I don't expect them to stay that low.

I don't know why your dad has such incredibly high energy costs, but there may be ways he can cut that significantly such as having the car charge over night.

For 99.9% of people in the US and Europe, an EV is a lot cheaper than driving any gas burning car.

Holy crap that's not cheap. I pay about 0.08CDN here in Ontario. Which suddenly makes it a lot more feasible. Especially since gas is more expensive here than in most of the US.

People that live near recently shuttered small coal plants have it a lot worse than people that live near nuclear and hydro.

A small community nearby has had some months where their rates have spiked to $1 per kw-h. There's a lot of last mile grid per person and I guess they don't have much of a collective agreement with the provider (the town here buys roughly the same power for ~$0.10 per kw-h). The people getting huge bills don't seem to be real big on cutting their use though.

My electric bill went up by about $80 the first month I got my electric car. Computing the cost is a bit tricky because I have tiered billing and I'm hitting the next higher tier since I got the car. My electric company (PG&E) does have an time-of-use billing plan tailored for EV, but, by my computations it didn't help a lot because we use A/C during the day:

https://www.pge.com/en_US/residential/solar-and-vehicles/opt...

If you charge at night and aren't home during the day, and your electric company has an EV plan, this might help.

For what it's worth, between CA, OR, and WA I haven't paid less than $2.59 anytime this summer. Where I live in eastern Washington state, it's been approximately $2.89 much of the summer.

Whereas where I live it's just starting to get above $2/gallon again. It's something that varies a lot by region/taxes.

The cost of driving is more than the cost of fuel alone. You also need to include wear and tear on the vehicle, the cost of insurance, and of course the cost of putting that CO2 in the environment, which is currently not a part of the price of gas.

The cost of driving is closer to $0.50/mile:

https://www.irs.gov/uac/newsroom/2016-standard-mileage-rates...

Is there a substantial difference in this cost when comparing an electric vehicle to a gas vehicle, though?

The parent's post was about cost of fuel (per mile), not the overall cost of driving.

An electric car has all of those same costs. The CO2 cost will be slightly higher, but 90+% of your electricity comes from CO2 generating facilities. Not sure where battery replacement will net out in terms of dollar and CO2 cost, but it is unlikely to be cheap.

Oil and gas prices are low now, but are not guaranteed to be over the next decade. You might want to use a cost number that has been averaged over a number of years.

Also the 90D is not exactly a car to be looking at if you are concerned about costs. I don't know if it allows you to choose a more efficient model.

Wouldn't the increase in demand for electricity also increase the price? Also, if the majority of consumers start switching to electric, I'm pretty sure the automobile and oil companies will respond. Not that that's a bad thing or anything.

It's hard to say, utilities can't just jack up their prices whenever they want. However, it's possible that there might be capacity issues, where there's more demand for electricity at peak times than can be generated.

I live in zipcode 23233 in the Richmond,VA, USA area. Gas is about $1.90/gallon right now and my power is about $0.09/KWh. I guess you can say YMMV.

His electrical rate is terrible, however. And, Tesla is not particularly efficient compared to, for instance, the BMW i3...

All that assuming residential recharge. Power stations with fast revharge will need a profit, so expect energy there cost more.

Not necessarily. Often, large commercial electric consumers pay less per kilowatt than you'd pay at home.

One major reason for this is that the load for these users is usually constant and predictable. The load at a fast charging station would necessarily be spiky and most likely bimodal (going to/from work, I'd imagine), so their cost wouldn't go down as much as, say, a steel forge with massive arc furnaces.

That's on top of the added cost of an electric vehicle. Worse, how does it handle the Chicago winter? I'll be running the heater 6 months out of the year, which is a drain on the battery, but on a ICE-based car, it just uses excess heat with no cost on fuel. So its tough to figure out what my real cost per mile will be in the winter.

I think TCO is going to be difficult to calculate for many people, especially when you're on tiered electric pricing that punishes heavy users. Electrics may have an uphill battle to popular adoption if the PR narrative is 'save money' instead of the other benefits of electric. I can't imagine the Model 3 edging out the Civic or Fit and other cars for TCO-minded consumers.

The only Telsa owner I know here in Chicago told me that his electric bill went up about how much he was spending on gas before. I suspect this is going to be the case for many.

Doesn't the electromotor also produce excess heat that can be used in a similar way?

My understanding is that heat is generated by tapping into the battery. There's no coolant to tap into and the electric motor is fan or passively cooled. Because they're so efficient there's no waste heat for the cabin.

It does, but it's a matter of <20% efficiency versus >80% efficiency. Not enough to heat up the cabin.

Not that it matters for a Tesla though. A Leaf feels the effects of running the heater more.

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