Thanks for the replies guys. It all helps me get a better view.*
- ( I can’t spell ‘perspective.’ )
The problems with swappable batteries aren’t technical–it is certainly feasible to design a car where the battery pack can be swapped out within a few minutes–but logistical. It is one thing to talk about swapping the battery out for a single vehicle manually, using a forklift and installing it into a charging station, but any discussion of doing so on a large scale needs to address the weight, storage space, inventory, safety, and costs of doing it on a routine basis (several vehicles at a time for dozens of vehicles and hours), not to mention the need for a modular, standardized system across vehicles. Practically speaking, being able to swap batteries would require having a storehouse of hundreds or thousands of battery packs in some kind of charging rack fashion; basically, a medium to large warehouse. Having the storage and retrieval of batteries from the storehouse would need to be automated to support any rapid turnaround, which is certainly possible but will require substantial infrastructure and design as well as regular maintenance. In general, having people out of the process of handling the batteries throughout the reloading cycle is desirable given the weight and potential for injury.
There are also significant safety concerns with the dense storage and changing batteries, and particularly lithium-ion batteries; should the casing be damaged or the battery experience thermal runaway (the cell gets so hot that the electrolyte and substrate begin to break down, melting or rupturing the casing and exposing the internal energetic materials to the environment). In such a case, the battery may catch fire or even explode (low order detonation, but still quite dramatic), which isn’t a huge problem with single batteries but if stored next to other batteries may cause them to catch fire or explode. If you want to imagine the destructiveness of such an occurrence look at videos of the PEPCON disaster, in which ammonium perchlorate caught fire and energetically released the stored energy in dramatic fashion. It was very fortunate that Pacific Engineering and Production Company of Nevada was located in a fairly remote location and the damage was largely limited to the facility and nearby structures. If this had been located someplace more accessible (as a battery swapping station would need to be) the damage and loss of life may have been catastrophic. In order to mitigate this, a mass quantity of batteries would need to be stored the same way large amounts of ordnance or solid rocket motors are; that is in earth-covered bunkers (“igloos”) with observing quantity-distance (QD) rules for the amount of material that can be stored and handled in any one zone.
Electric cars will definitely have a future for commuters who have a daily transit that is within the charging range of a reasonably sized battery pack. But the notion of easily swapping out battery packs weighing many hundreds or thousands of pounds, or advancing battery technology such that they can be fully charged in the same span of time it takes to fuel an internal combustion vehicle is just not practical. Liquid hydrocarbon fuels (LPG, ethanol, methanol, or DME) will still be needed for long range and over-the-road heavy haul transport for the foreseeable future in combustion engines, fuel cells, or hybrid electric vehicles, even after natural petroleum resources are exhausted. Without some technomagical advance in electrochemical battery technology all-electric long range over the road transportation is not practical.
Stranger
I think a better comparison is putting gasoline in a diesel tank. Diesel cars are uncommon in the US and there’s no common knowledge of how to maintain them.
I went with a friend to buy a new car, and she decided on a diesel Passat. They did mention a couple of times that putting gas in the tank would destroy the engine. And of course the fuel port has some protections on it. Nevertheless, numerous people still manage the feat and cause massive damage. Is that Volkswagen’s fault?
I think this is a case where it’s the consumer’s fault but Tesla’s problem. The fact that we’re still talking about it today proves this. Happily, there was a technological fix.
Depends on what you mean by “practical” (or, “what’s the price of diesel in your near-future world?”).
It’s not difficult to sketch out a semi truck design with 700 mile range with current technology. This is about the limit of what’s allowed legally for a day of driving under US law. After that is a required 10 hour rest period. That’s long enough for the battery to recharge with available chemistries.
A battery this large is expensive and takes a significant chunk of cargo space. However, it’s still a perfectly functional truck that would be practical if fuel was expensive enough.
I wonder how automated driving changes the picture. On one hand, your truck can now drive 24 hours a day and there’s no sleep time to overlap with charging. On the other hand, the costs of running the truck may now be reduced enough that idle time isn’t a big deal. It’s a complicated problem.
On the topic of battery swapping: personally I think it’ll never be commonplace, but for a slightly different reason than what others are citing.
I think it’s true that you need a kind of modular, universal pack to make the system work. But I think it’s false that you can make a long range electric around a modular pack.
An electric car that’s more than a go-cart has to be designed around the battery. The battery is a structural component of the vehicle. Not all cars will have a flat pack below the passenger compartment like the Model S, but if any long-range models are released they’ll require something custom. It’s like a fighter jet where, to a first approximation, you pick an engine and then design a plane around it (or like the A-10 where you pick a gun and design a plane around it :)).
These packs may be removable but each one will be unique. Swap stations can’t be expected to have dozens or hundreds of pack types on hand, and besides, handling them in automated fashion would be virtually impossible.
So I don’t see it happening except on a small scale, like with Tesla’s system (which only serves the Model S, and presumably the X).
Exactly. Letting an electric car battery run down is NOT equivalent to running a car without oil, regardless of whatever ass-covering BS Tesla might claim. It’s analogous to running out of gas, which really isn’t that big a deal. You put in more gas & go; it’s more of an embarrassment than anything else. Not letting the battery run down is absolutely something that needs to be taught, because there really isn’t anything comparable in a regular car.
It seems to me that that’s a terrible application for an electric car. OK, yes, it’s an even worse application for a gasoline car, but the proper vehicle for your situation would be a bicycle (which costs less, requires less maintenance, and uses less energy than any motorized car).
I can’t speak for sbunny8 but not everyone can ride a bicycle. My wife never learned and at age 45, she probably never will.
For a two mile commute, shanks’ pony should suffice.
Destroy? No. Damage part of the fuel system? Maybe.
I was led to believe that fixing the damage would cost well north of $10k. Maybe that was an exaggeration, but it seemed plausible enough. The fuel system isn’t exactly a small and localized part of the vehicle.
I didn’t want to confuse the issue by discussing bicycles, but the truth is that I do usually ride my bicycle during Daylight Saving Time, when the sun is still up at the end of the day. The EV is actually a company vehicle which belongs to the corporation of which I am the only shareholder. In the winter time, I assign that vehicle to myself for commuting but in the summer I assign it to my assistant manager in case we have an emergency in the middle of the night. His house is about 7 miles away, which is a bit far for most people to ride a bike.
Oddly enough, I calculated that the energy usage of the bicycle isn’t much less than that of the EV. The cost of the food that it takes for me to eat and burn the calories pedaling the bike is almost as much per mile as the cost of buying electricity for the EV. That’s partly because electricity is cheap in the Pacific NW and partly because I don’t buy junk food. And the depreciation and repairs cost of a bicycle aren’t negligible either. I ride my bike about 1,000 miles a year, and it costs me about $200 to maintain it, so that’s 20 cents per mile right there. The main advantage of the bicycle compared to the EV is that the fuel is entirely renewable, and I get exercise.
There are plenty of people who buy a $99 bicycle and only ride it a couple hundred miles before they sell it at a yard sale 10 years later for $25. That works out to 37 cents per mile just for depreciation.
According to my calculations, driving an average gasoline car costs about 60 cents per mile (of which 20 cents is fuel) and driving an EV also costs about 60 cents per mile (higher purchase price and depreciation, but fuel cost is only 3 cents per mile if you live on the east coast, or 2 cents if you live in Oregon) and riding a bicycle costs between 10 and 40 cents per mile depending on how many miles to ride per year (of which 1-2 cent is fuel costs).
Nobody has addressed the original question. I drive a Chevy Volt and have a 40 mile daily commute which means I need to plug in every night or else rely on the gasoline engine the next day. Every so often I come out to my car in the morning to find the charge door open but the charge cord not connected. :smack: For one reason or another I remembered to pop the charge door open but got distracted before I actually plugged the cable in. So, what happens when someone with a fully electric car does this? He has to find another way to get to work that day. What’s needed is some fail-safe mechanism that that would alert the owner that he had forgotten to plug the charging cable in. Is there an App for that? :rolleyes:
When you say your daily commute is 40 miles, I assume you mean round-trip. So that’s 20 miles one way and your Chevy Volt has a battery range of 40 miles. If you had a 40-mile commute and you bought an electric-only EV with a range of just 40 miles then yeah you’d have quite a problem if you forgot to plug it in and the next morning realized, oops, you have zero charge left in your battery.
I would never recommend buying an electric-only EV whose range is exactly equal to your daily commute. That’s a recipe for trouble.
Now, if you had bought a Nissan Leaf, with a range of 84 miles, and you drove 20 miles to work and 20 miles back, you’d still have a 55% charge remaining at the end of the day. So you’d be okay unless you forgot two days in a row.
What if you had bought a Mitsubishi i-Miev, which has a range of 62 miles? You’d drive 20 miles to work and 20 miles back and have a 3/8th charge (22 miles remaining). You should plug it in overnight. Let’s say you forgot. Now what? It’s Tuesday morning and you have 22 miles worth of charge left. You have lots of options…
#1 Leave the EV plugged in at home and take a taxi to work.
#2 Drive the EV to work and plug it in there. By the end of the working day it’ll be half charged, more than sufficient to get you back home again.
#3 Drive the EV to the nearest CHAdeMO charger (assuming you have a CHAdeMO port. It’s an optional extra on the i-Miev, standard equipment on the Leaf), plug in for 20 minutes and get an 80% charge. Now you’re 20 minutes late for work but you didn’t have to pay for a taxi.
#4 Drive the EV to work as usual and then on your way home drive really slow to the nearest CHAdeMO charger, get an 80% charge in 20 minutes, drive the rest of the way home. Now you’re not late for work but your drive home takes longer.
To anyone out there who’s pondering the idea of buying an EV, I would suggest you first ask yourself how far you have to drive every day and can you plug in at work on a reliable basis. If you can plug in at work, shop for an EV whose range is at least 3x the one-way distance to work. If you can’t plug in at work, figure 3x the round-trip distance. So if you work 20 miles from home and you can’t plug in at work then I would suggest an EV with a range of at least 120 miles (like the Tesla Model S, 208 miles standard range) or a plug-in gas-electric hybrid (like the Chevy Volt, which Carlarm has). But if you can plug in at work then I’d suggest an EV with a range of at least 60 miles, and there are plenty of those to choose from.
It is? That’s only about 40 minutes.
On the other hand, my previous bike cost about that much, but I got somewhere between 2 and 3 thousand miles on it (wow, I’d never actually worked it out before-- I didn’t realize it was that much). My current bike was about twice that, but should last much longer. If you’re using a bike for commuting, you’re going to put on a lot more than a couple hundred miles.
Also don’t forget about insurance when you’re counting up the cost of a car.
Don’t forget that bicycling is about 6 times more fatal than driving per mile. 72250 (working days)=3500 miles/yr bicycling has an additional fatality risk of around 0.0002/yr. If we assume a sorta middling value of a life at $6M, that’s worth about $1200 (more than my car insurance, for what its worth).
Not to mention opportunity cost. I live several miles from work, and bicycling would add about an hour per day of commute time. That’s a crapload of time I could be using for other purposes.
Supposing a car gets around 1.5 min/mile and a bicycle 6 min/mi, that’s a difference of 4.5 min/mi. The IRS seems to think the cost of running a car with all the factors is around $0.56/mi. If you make more than $0.56/4.5 min, or $7.46/hr, then bicycling is a net loss in raw monetary terms.
Obviously I’m ignoring any health benefits, which are going to be too variable to be of much use in a comparison.
Sure they did.
Most people with pure BEVs have enough battery capacity that they do not need to charge every day for their routine commutes. For most the result of being a spaced out doofus who forgets to plug in as (s)he pulls in for the night will be … nothing.
Of course the other side of that observation is that a typical pure BEV owner is therefore in possission of a battery with at least twice the capacity they need for most days’ usage. And the battery is, at this point at least, a costly item both in terms of dollars and in terms of lifecycle environmental impact.
Which is an argument (mind you there are arguments on the other side too) for choosig a plug-in hybrid with a battery sized to cover the vast majority of daily commutes and not much more. The ICE will be used infrequently on a daily basis (albeit current versions will often turn on in winter to warm the battery up and supply for the needs of defrosting and heat) allowing the ICE to be an extremely low mileage item and the vehicle still offers the utility of being able to travel cross country at a moment’s notice.
BTW an interesting aside - I recall reading early on that most public charging was being done by those with plug-in hybrids not pure BEVs. The pure BEV had plenty of juice to get home on its electric power; the plug-in hybrid user can always keep going on gas but really wants not to - having the ICE turn on always feels like a small failure.
Right now ytd sales to August (and August was a slow month) are:
almost 20K Teslas (est.);
19K Nissan Leafs;
14 to 15K in the plug-in hybrid Ford Energi line (both Fusion and C-Max Energis);
13 to 14K Volts (counting a few hundred ELRs);
11 to 12 K Prius plug-ins (if you count them given their tiny EV only range);
and about 2K BMWis and a few others that are less than 2K each (the Smart ED, the Focus electric, Hondas offereings, etc.)
Roughly equal numbers buying pure BEV and plug-in hybrids. Interestingly the Leaf is increasing its sales as are Ford’s Energi plug-ins, while the Volt’s sales are lagging. Might be because potential customers are waiting for an expected improved model to be released?
One more thing you should consider. The range on a EV is probably a lot like the EPA fuel mileage numbers. Not realistic for many people.
Power consumption in both a gas car or an electric car is dependent on several factors. Among them
Speed driven
Number of stops and duration
Terrain
Driving style
I can tell you from years of experience there are lots of people out there that complain that their car with an EPA of 38MPG only gets 18MPG. Yet I can drive their car and get over 38MPG.
Personally I would want a large margin range margin for a car to commute in.
For the examples above a Leaf would be a good choice. IMHO the Mitsubishi would be marginal at best and might not get you home based on the factors I listed above.
I find it very ironic that you’ve linked to an article whose title is Bicycling: The SAFEST Form of Transportation in order to support your claim that it’s 6 times more fatal than cars. I’m aware that you are figuring it per mile and the article you’re linking to figures it per hour. But I think you have missed a key point which is that the statistics you’re looking at include ALL cycling and ALL driving, when really we should be comparing commuting. Cars are much more dangerous in a commuting environment than they are in a cross-country highway mileage environment and the latter skews the statistics making cars appear safer than they really are. I’ve read other sources which conclude that when you look at fatal bicycle crashes and compare them to car trips of similar length, cars are equally dangerous.
And that is a major point of the article you linked to. They are saying the health benefits far outweigh the risks.
But we should get back to the topic of the thread, which is what happens when you forget to plug in your EV.
Speaking as an EV owner, I can say that I’ve never had to find another way to get to work because I forgot to plug in the previous night. On the few occasions when I forgot, I still had enough of a charge to get to work anyway, and then I could plug in at work. But I admit that this would be a bigger problem if I lived farther away from work.
Yes, that’s true for any car but especially for an EV. If I drive my Mitsubishi at a steady 30 mph on a warm day I can get over 90 miles from a single charge. But if I drive it 60 mph on a cold night, I might only get 35 miles on a charge. The EPA says the Mitsubishi’s range is 62 miles; that’s an average, not a maximum. If your daily commute involves highway speeds and/or steep hills, you can expect to get fewer miles on a charge than the EPA estimate.
Conversely, the good news is that if you’re driving along on the freeway at 65 and the range meter says you only have 12 miles remaining but you’re 15 miles from home, there is something you can do about it! Take the next exit and drive the back roads at 40 mph and you’ll find that the range meter will adjust and say you have 18 miles remaining. So you can make it home with 3 miles to spare.
I chose that link on purpose to make the data seem trustworthy :). I won’t argue the authors other points; just that if we’re looking at commuting, per-mile is the only way that makes sense. Though for me, bicycling is even worse; the only route that is even remotely safe (i.e., not along a 50 mph expressway) is about 25% longer.
There used to be a website with a bunch of good cycling safety data, but it’s been down for a while now (I think there are mirrors). The author was killed on his bicycle by a drunk driver.
Why shouldn’t the same apply to bicycles, though? Bicycling for leisure out in the country is bound to be pretty safe. Sharing lanes with cars on a commute route is bound to be dangerous. I don’t know which one scales more.
The article fails to account for the time spent actually bicycling, though (I suppose the author finds it enjoyable, and doesn’t think of it as a loss). And the claim about the health benefits are from a study that claims exercising has a multiplicative effect on lifespan. That’s great, but what if you’re already healthy, or get exercise from other sources? Exercise only helps to a point.