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Comment by bruce511 | Hacker News Reader

In an EV about 90% of the energy used is converted into motion. About 10% goes to heat. [1][3]

In an ICE engine about 30% of the energy becomes motion. About 70% is heat.[2]

In other words electric motors are about 3 times more efficient than ICE.

[1] an interesting side effect of this is that in cold climates you can't just harvest waste heat to heat the cabin (or batteries. ) So you end up using some battery energy if you need heat.

[2] ICE motors vary in effeciency a lot. 20-30% is typical. The Carnot formula comes into play here.

[3] because there is so little heat generated, the cooling systems (EVs still have them) are much smaller. And simpler (for example, no fan, 'cause there's no heat when standing still.)

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Who cares about motor efficiency when you can only take 10% as much fuel. At the end of the day, cost is the only metric that matters.

The cost of EV energy (to the driver) is about half that of the cost of gas energy. And that's if you buy electricity at charging stations [1].

If you charge at home it gets less. If you have solar at home it approaches zero.

Yes, the cost of the car itself is a factor, but even there prices are dropping all the time.

>> when you can only take 10% as much fuel

effeciency makes all the difference when we discuss % of fuel. 90% of 100 mj is the same as 30% of 300 mj. So already the "fuel" can be 66% less. Generally though the raw amount of mj isn't a very important number. A better measure (which takes effeciency, and tank size into account) is "range". But even that is somewhat meaningless. At some point range is "enough". For daily commutes that may be 50 miles. For long-distance it might be 500 miles.

In only a very few cases would a pickup with 2000 mile range be more useful than one with 1000 mile range.

Plus you can also factor in maintenance costs. The cost of ownership of an ev, from a service and maintenance point of view is a lot lower.

[1] ymmv somewhat. Although electricity prices vary a lot, so do gas prices. The 50% saving (at worst) is a pretty good rule of thumb though.

Indeed, solar panels and EVs are the way of the self-sufficient rugged individualist. It's an amazing PR and marketing coup to make it the other way around and presented as something for "liberal weaklings" etc.

Right, the set of people who actually pump their own oil out of the ground, refine it into something you can put in a modern vehicle engine and drive around on that is likely zero, but the set of people who own panels and storage so they can fill their EV includes my team lead, who is just some guy on a pretty average salary living on a modern housing estate.

The bio-fuel people at least make some kind of sense compared to fossil fuel "survivalists" - but again they're portrayed as just tree huggers!

>It's an amazing PR and marketing coup to make it the other way around and presented as something for "liberal weaklings" etc.

If there is such a marketing, then people relate to it because EVs are not suited for handling unpredictable situation. You got stuck in a ditch in the middle of nowhere at night, you loss all of your battery getting out of it, and now you are stuck. So you can't take it to unforgiving places.

EVs are great for boring commute that is it. I don't see it changing any time soon.

Surely you call a recovery truck to come pull you out and do an emergency charge on your battery, similar to how they’d provide you with emergency gas if your tank ran dry? Or tow you if they don’t have a charger?

Tow trucks are sometimes needed for gasoline cars too.

If you run out of gas you’re also stuck. Only upside is that the recovery service can bring you a few gallons of fuel instead of a tow.

I somewhat suspect that's a temporary state of affairs. Nothing prevents a couple tons of batteries being put on a truck with a CCS charger to achieve the same thing.

It won't be efficient but neither is driving a few liters of fuel to someone from a gas station.

Such things already exist in Europe. The RAC for instance:

https://www.thecarexpert.co.uk/call-breakdown-provider-ev-ru...

If you slide off the road and get stuck in a ditch in the middle of the night, an EV is a lot more comfortable. Standard advice for keeping warm is to run the engine for ten minutes every hour and keep the window cracked open due to risk of carbon monoxide poisoning. By contrast, you can leave the EV with the heat on all night.

> You got stuck in a ditch in the middle of nowhere at night, you loss all of your battery getting out of it, and now you are stuck.

I find it interesting how you’re presenting that incredibly unlikely scenario as a serious objection to an EV when simply going off the road is a once in a lifetime or less situation for most drivers, much less precisely calibrating it so your vehicle is not damaged too much to be unusable but still needed a massive amount of power to get free.

That’s an interesting counterpoint to something which happens to thousands drivers every year: having a bad storm cause them to sit in lengthy lines waiting for fuel (this was weeks the last time I was in Florida) or, in colder weather, idling through a tank of gas while stuck waiting for ice to be cleared.

The EV also has a ton more torque to get out of the ditch, and can apply it at very low speeds.

A 4x4 with a 4L gear can give you all the torque you need, and it will provide it all day long.

>going off the road is a once in a lifetime or less situation for most driver

In my country, one don't have to go off road to get in that situation. Here I can never trust an EV like I trust an ICE for going to unfamiliar places.

I have said it multiple times, but it is just wishful thinking that humanity will behave differently/responsibly w.r.t disposal/recycle of batteries as EVs start replace ICEs on a global scale. I think it will be an even bigger problem than the current issue with green house gas emissions as the current generation appear to be greatly apologetic to the associated issues, as the past, generation were to the issues of ICE.

The circle of collective blindness repeats!

You have used multiple gallons of gas getting "unstuck" from somewhere? That is a ridiculous scenario.

The point is that I have the lee way to even attempt it...

How often are you driving into ditches at night? Typically this is something that only happens somewhere between never and once to most drivers in their lifetime, and the ones that do end up in a ditch are usually drunk.

Aside from anything else, if you're in a ditch your car probably isn't drivable and needs towing somewhere to get fixed anyway. Whether you've used 100km of EV range trying and failing to get out of the ditch of 100km worth of fuel trying to get out of the ditch is irrelevant. If you need to use that much effort to get out of the ditch before realising it's a stupid plan that's not going to work and the correct solution is to call a tow truck, then you definitely shouldn't be driving that vehicle anyway.

A standard EV battery can power seat heaters for about a month. If you're "stuck in a ditch" you're better off with an electric car.

I think 1600 watts of solar panels produces enough energy to drive an EV 12000 miles a year. Your car though would have to be always plugged in during the day. But probably 3200 watts would be enough for a car used for commuting to be charged mornings, evenings, and weekends.

> Your car though would have to be always plugged in during the day

Or just have a second stationary battery to store up the energy while you're away during the day.

Two cars, much cheaper than a second battery pack. And you have a supply of rolling spare parts.

This is probably the case right now, but I have faith the market will mature and fix that absurdity.

i was thinking used where you can get a Nissan Leaf which is a 75 kW, 20 kWh rolling battery pack.

That's no longer the case. You can buy Chinese rack batteries for prices approaching $100/kWh.

Are they UL certified? If so do you have a brand you can point me at by any chance?

> UL certified?

Not generally, although some are. The UL certification will put you at the top end of the $100 - $200 / kWh range I mentioned. Eco-worthy and UZ are two brands with such certification.

Will Prowse reviews a bunch of these.

Thanks :)

Not to be picky, but 1600w is a really small solar system. These days a panel is around 500w.

Where I stay 8 panels is a "small" system. I have 20. In summer that generates 85% of my household needs. (It would be 100% but I deliberately only got a very small 5kw battery.)

In winter it's less (mostly because of heating requirements). But I have space for some more panels, so I'm running the numbers. (I'm currently getting 16% return on capital spent, and there's a point of diminishing returns.)

Obviously ymmv. There are roof, and land, constraints. There are financial constraints etc. But being off-grid, or partially off grid, is very possible for a lot of folk.

Just making the point that the cost of solar panels to power a car is a fraction of the purchase price of the car.

If the world can afford to manufacture 100 million light vehicles a year it can afford to manufacture the solar panels to power them.

Before the Iran war, I did a back of the envelope calculation for the price of gas of your average ICE for a certain fixed range vs. the price of electricity an average EV uses for the same range. This was under the assumption that you buy electricity at a random charging station that you don't have a contract with.

Based on these average values I used, EVs fared slightly worse.

This was not factoring in costs of purchase or repairs etc. And all averages were taken off the internet so everything had to be taken with more than a grain of salt. But the outcome was nowhere near your statement of EV energy costing about half of the cost of gas for the driver.

Doing the equation regularly would be interesting.

There are some other parameters to consider too. Stopping for fuel is not something I enjoyed. I can charge at home. You won’t have to stop to refuel in an EV unless you’re going a long way. If you’re going a long way the stop will be longer. Much worse.

You won’t service an EV much, that’s nice.

The silence is bliss.

Were you using DC fast charging stations or level 2? Fast charging is about 2x the price.

If you think about it as "buying fuel" rather than as just a routine part of owning the vehicle I think the "fast charging" seems like how you'd do it. Like how at the turn of the century people bought a mobile telephone to make telephone calls. What do mean it's a computer? Why would you want a handheld computer?

Humans are like this about a lot of things, imagine what it was like before widespread universal literacy. Why are we teaching everybody to read? What are they going to do with that skill? Until you've tried it, the fact that your entire populace can read doesn't seem like it would make a big difference.

Yes, this. I notice most people unhappy with the EV concept are also not EV owners. Which makes sense, they've chosen not to get one.

And yes, there are also EV owners who are unhappy, but they are much less common. In general, when I talk to EV owners they would not go back to ICE.

Yes, I hear the objections. But I also see communities overcoming those problems. I was in London a couple weeks ago, and I saw multiple EV's parked on the street being charged from the nearest lamppost. This in areas with little to no off-street parking.

I noticed in parking garages more and more charging points. And so on.

Yes, I imagine price does vary. But if the landlord in my office block puts in electric chargers then I expect we'd negotiate the price with him. He wants to keep tenants happy. We want to keep staff happy. I imagine cost of the actual electricity to the employee would be barely above municipal cost rate (if not below it.)

When it comes to charging availability, it's a problem that's pretty easy to solve. The difference in the last 5 years is remarkable. And it will continue to expand as demand picks up. And it can be solved by individuals with individual capital. So it can happen almost overnight.

> buy electricity at a random charging station

Well there's your problem. Try doing the same calculation with the average residential electricity cost. Most car use is for commutes after all, so most people can just charge their EV in their driveway every night.

Destination charging and rapid charging are notoriously expensive. It's a luxury product intended for a once-a-year road trip. It is not even remotely representative of your average charging cost. Street-side charging is slightly less excessive, but you're still paying a serious premium.

> so most people can just charge their EV in their driveway every night.

That does presume that those "most people" have a driveway where they can do charging. I.e., all apartment dwellers with cars in parking lots/garages (excluding those few that may have installed electrical plugs at each parking spot) are cut off, as are city dwellers without driveways who park on the street (or in another garage, again without electric hookups for charging).

Yes, eventually those garages and parking lots will likely include some form of "car charging" infrastructure, but until that happens, "most" is not as big of a percentage as that word makes it appear.

It's probably too much to say everybody can do this, but a lot more can than seem to be included in typical estimates. Tomorrow I will walk to work and probably (if the owner hasn't left by then) I'll pass an EV that's plugged in to presumably an ordinary mains supply... via a hole cut in their fence because their car is sat on the street. I'm sure that sometimes they find somebody else took their prime parking spot, but not often. And of course "run the cable through the hole in my fence and lay down the conduit to protect it" isn't exactly an ideal setup, but it works and the car doesn't care how the electricity got there.

In the city you just take the bus or metro. Did that for 22 years, no issues.

> until that happens

Maybe society can coordinate that? The CO2 being emitted isn't waiting

We just bought our first (used) EV, and charging stations are the Wild West right now. Any random station you pull up to might charge close to the local cost of electricity, or some wild sky-high amount. And hopefully they’ll tell you what that is before you have to swipe your card. There the economics can swing towards gas cars depending on how absurd your local charging station prices are. For people filling their tank every couple days because of a 2 hour commute or something an EV may still not make sense financially. But if you’re putting in under 40 miles and have even a modest 120v 12 amp circuit you can plug into at home (e.g. a dedicated washing machine circuit) you’ll likely only need a charging station on rare occasions such as a road trip. As a matter of fact I am writing this from our first EV road trip. The inconvenience has been comparatively minor and our “fuel” costs should end up being about half of what they would have been in our hybrid SUV.

The Toyota Prius and the Rav hybrids are popular for many of the reasons you mentioned.

I've only had an EV 3 months now, but it'll never see a charging station.

I pay around $.12/kw and get 4 miles per kw. So my "energy" costs are $.03/mile. I have a Mazda cx50 as well, it gets about 20-22mpg, with the gas prices here in Seattle that's around $.30/mile. Even where gas is cheaper that's still $.20/mile. Literally 10x the cost to run a gas car vs an EV.

I'm honestly shocked at how many people have EVs and rely on charging stations. I mean, I think it's a low number, but the fact that it's more than zero is shocking to me.

The pacific northwest’s vast hydro capacity makes it maximally attractive to own an EV. The rest of the country isn’t nearly so lucky.

I’m at $0.11 in Maryland which gets 40% of its power from nuclear.

Maybe it’s not as much cheaper but it’s cheaper than gas anywhere in the country.

I'm in the EU and the factor is 3-4x.

One of the reasons Norway can go all electric (EV’s), but most of the world doesn’t have the hydroelectric resources they have.

Neither Oregon nor Washington are in the top 10 states for cheapest residential power. Everywhere except for the Northeast and California has prices within a few cents per kWh of the Pacific Northwest.

Doesn't make electricity much cheaper

Seattle City Light owns a sizable chunk of its generating capacity.

Is the hydro power already mostly consumed?

What actually matters is where extra generation occurs to handle the marginal new load of new electric vehicles.

Everyone fools themselves because they look at the current percentage of hydropower and think that is what powers their car - when it rarely is.

I don't think most people care where their electricity comes from, just the price.

More people own cars than houses. I live in an apartment, and the only ways I'd be able to charge an electric car are expensive charging stations or plugging in an extension cord, leaving a sliding door cracked all night and hoping the property's management doesn't throw a fit, pets don't sneak out, somebody doesn't break in, etc.

I've got a hybrid now, at least.

There’s plenty of cheap charging to be had in parking lots you’d otherwise park in. Many employers have charging stations. Plenty of apartments offer charging.

But even if you can’t find any of those, L2 charging at stations is half as expensive as fast charging.

In my area the fuel cost of a hybrid car is a better deal than recharging an EV at PG&E retail rates, but this is just a policy knob that we can turn whenever we decide to get serious about reducing greenhouse gas emissions. If people are ambivalent about the operating costs of EVs then it is up to the government to put their thumb on the scale with a motor fuel tax, such that EVs look like a great bargain.

Before I drove an EV, I drove a 50 mpg Prius. At California prices of ~$4/gallon, that’s $.08/mile.

My post wildfires NEM2 off peak rate for electricity is $.40/kWh. My Bolt gets 4.5 miles/kWh. That’s $.1125/mile.

If I were driving a Tesla it would be worse (my wife’s Tesla lies mercilessly about its range when full; it’s like Elon Musk recapitulates himself; real world it gets about 3.5 miles/kWh), and if I drove a Rivian it would be MUCH worse.

So, in California, it isn’t true at all (mostly because rate payers are funding PG&E’s liability) that the most efficient EVs are cheaper than a good mileage gas car. No where near a 2x advantage (it was better, but not nearly 50%, when I bought it, more like 90% of the gas cost). At no point has it ever been close to 50% cheaper for fuel in California (which, as it happens, sells by far the most EVs).

Generally speaking, I think EV proponents (like me!) should spend a lot less time promoting “it’s cheaper”. It is, in practice, cheaper, because maintenance is cheaper. But Americans don’t care about levelized costs, they care about the highest salience variable expenses, and trying to convince them to do otherwise is a losing argument.

Regarding range, and this is true for ICE too, how you drive matters enormously. There are lots of techniques that improve gas consumption or range.

And yes, I'm sure there are places where gas and electricity get closer together. In the US gas is mostly untaxed. So it's closer. Elsewhere the tax-cost of gas works in EVs favor. [1].

Also I think PG&E is perhaps not representative of electricity producers.

So sure, in your area, the finances only make sense if you factor in maintenance. And if gas prices remain stable. And if you don't have solar. But again, all these factors vary wildly in various places.

[1] in the long run these taxes will need to be made up elsewhere. So that's a temp saving. But I'm enjoying it while it lasts.

My xpeng g9 goes about 570km in summer. Less in winter, like 480 maybe. Longest range ICE i had was a mercedes wagon that went 1050km on one tank of gas.

Filling the wagon today would cost me like 170 euro. Filling my xpeng happens overnight and is about 7-9 euro depending on grid pricing.

> cost is the only metric that matters.

Negative externalities like pollution and climate change are not even priced in. Even if they were priced in, there are non-monetary factors that we could consider once in a while, but the conversation tends back to dollars.

Many countries have high fuel taxes that approximate pricing in the negative externalities.

Assuming you think price as a signal is the solution to dealing with those externalities, it doesn't matter what caused the price to be high.

Fuel taxes are "in theory" the mechanism to price these in, but today, they are not, and how this money eventually has the opposite effect! Revenue from fuel taxes is usually funneled to more transportation infrastructure (> 80% to road construction in the US, only 15% to mass transit). The vast (and ironic!) indirect effect is more cars, more car miles, and more consumption--a long-term, indirect subsidy to fuel and auto industries. Approximately zero goes to regulation enforcement (like emissions inspections and other enforcement), which is funded by usage fees and general income taxes.

My underlying point is that money is fungible.

How you account for the tax dollars received doesn't affect the pricing signal.

We have accounting systems to colour tax dollars. However that doesn't mean you can define cause and effect like you are attempting to do. Although I've no idea what we should do.

The commenters above, is the answer to your question. Based on their discussion, there are metrics besides cost that matter to them.

Not everyone is you.

Very, very few people actually need to drive 500 miles in a day. Tank size is about convenience, about how often you need to go get gas and what times of day the stations are open.

You can recharge your car at home every night. At 2 in the morning.

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