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Electric cars: The death of the internal combustion engine

economist.com

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Re: Electric cars: The death of the internal combustion engine

#71

Post by falcolas »

kumarvvr wrote: post #63
falcolas wrote: post #52

Earlier quoted context omitted.

I'd still prefer a turbine, for many of the same reasons as an electric motor. Fewer moving parts, more fuel efficient. As a point of their reliability, most of the old pumpjacks you've seen about (if you're my age) are powered by turbines. Turned on, and left running for years without stopping.

I am under the impression that as the size of a turbine reduces, to maintain the same efficiency, you'd have to increase the running speed. So for small turbines and with safe speeds, I guess the efficiency is compromised. Having said that, I have come across efficient micro-turbines.

I don't have enough knowledge to discuss the power/fuel consumption of miniature turbines compared to a similarly sized ICE, but for those with that knowledge:

http://www.jetmodelproducts.com/amt.htm

157 N/16KG thrust at 450 g/min (grams, not gallons ;))

Re: Electric cars: The death of the internal combustion engine

#72

Post by [deleted] »

lordvon wrote: post #45
pilom wrote: post #36

US drivers drive 3.1 Trillions miles per year [0]. Every month, the 12 Month moving average has been going up at 5 billion miles [0]. So every month we need to install enough charging stations to charge 5 billion miles/year. Lets use a Level 2 charger that adds ~25 miles of charge per hour. So 5B miles / 25 miles of charge per hour / 24 hours per day / 365 days per year = about 23,000 Level 2 chargers need to be adde…

How do you account for charging at home?

[deleted]

Re: Electric cars: The death of the internal combustion engine

#73

Post by kumarvvr »

falcolas wrote: post #71
kumarvvr wrote: post #63

Earlier quoted context omitted.

I am under the impression that as the size of a turbine reduces, to maintain the same efficiency, you'd have to increase the running speed. So for small turbines and with safe speeds, I guess the efficiency is compromised. Having said that, I have come across efficient micro-turbines.

I don't have enough knowledge to discuss the power/fuel consumption of miniature turbines compared to a similarly sized ICE, but for those with that knowledge: http://www.jetmodelproducts.com/amt.htm 157 N/16KG thrust at 450 g/min (grams, not gallons ;))

Ok, this looks like a Jet, to provide thrust. But to me, those parameters look like very poor fuel efficiency.

Re: Electric cars: The death of the internal combustion engine

#74

Post by curun1r »

bryanlarsen wrote: post #2

Anytime you make something cheaper, easier to use, more useful and/or more efficient you get an increase in usage. Autonomous electric cars are all 4, and will lead to a dramatic increase in the number of miles driven. Some of those miles we can imagine (for instance sending your car on a dead-head journey somewhere for somebody else to use it), but most of the increase will probably be from new usage models that we…

> But congestion? That's going to get a lot worse, it's not going to be the utopia that people here seem to expect.

Some congestion, but other congestion will get better. Parking shortage is a form of congestion that will get better when cars can drop you off rather than needing to find a parking space. Also, circling and searching for parking when there's little available causes congestion. There's few more frustrating driving experiences than being stuck behind someone going 10mph while looking for parking.

I can imagine one of the initial big selling points to self-driving cars will be a "go earn money" mode where, instead of parking your car, you tell it what time to come back and pick you up and it goes to drive for Uber/Lyft in the interim and accepts any ride that doesn't preclude it from returning in time.

Re: Electric cars: The death of the internal combustion engine

#75

Post by Karrot_Kream »

bryanlarsen wrote: post #2

Anytime you make something cheaper, easier to use, more useful and/or more efficient you get an increase in usage. Autonomous electric cars are all 4, and will lead to a dramatic increase in the number of miles driven. Some of those miles we can imagine (for instance sending your car on a dead-head journey somewhere for somebody else to use it), but most of the increase will probably be from new usage models that we…

Yeah I don't understand this enthusiasm for autonomous cars. It seems like the HN-crowd seems to wax enthusiasm for solutions that don't yet exist, and absolutely reject alternatives (bikes, public transit) that already exist and work. With new solutions comes new problems, and I can see congestion being a big one.

I guess it's not sexy to implement the tried-and-true, but it's a lot more sexy to dream.

Re: Electric cars: The death of the internal combustion engine

#76

Post by ghaff »

mikeash wrote: post #58
ghaff wrote: post #35

Earlier quoted context omitted.

Weed-whackers are probably not the best example. Apparently the current battery-powered ones are pretty good for typical personal home use. But absolutely for anything bigger or with a higher duty cycle (e.g. that lawn services would use).

Small engines like those are also horrendously dirty. A gas-powered lawnmower, for example, produces an order of magnitude more pollution than a car in the same amount of time. Weed whackers, despite being smaller, can be even worse because smallness means less complete combustion. Lawn equipment is fairly low-hanging fruit for electrification, much easier than cars, and would have a disproportionate impact on air qu…

The big difference is that two-cycle engines mix oil in with the gasoline. Something small like weed-whackers are usually two-cycle. Lawn mowers can be either.

As I said, the current crop of battery-powered weed whackers are apparently pretty good. When I've looked into robo electric-powered lawn mowers though, they really seemed to be for pretty minimal yards. I don't keep much of my property as lawn and, still, nothing out there seemed like it would be very effective.

Re: Electric cars: The death of the internal combustion engine

#77

Post by curun1r »

comicjk wrote: post #10
seibelj wrote: post #6

You don't realize it until you focus on it, but walking around a city, even a relatively clean one like Boston, how much of the air is full of exhaust. City busses that don't run on natural gas spew huge amounts of black smoke, it's disgusting. I can't wait until electric cars take over, the air is going to be so much cleaner, even in dense urban environments.

Getting rid of combustion in urban areas is one of the biggest public health wins available, on the same scale as famous past examples like banning leaded gasoline. The only reason we haven't already done it is lack of alternatives.

Especially now that we're seeing effects of air pollution that go beyond respiratory issues: https://www.ncbi.nlm.nih.gov/pubmed/25310992

Re: Electric cars: The death of the internal combustion engine

#78

Post by ghaff »

mywittyname wrote: post #54
twblalock wrote: post #27

Earlier quoted context omitted.

I worry that self-driving cars are going to be used as an excuse not to expand public transit, especially in the Bay Area. The problem is scale -- once the population reaches a certain size, the roads are going to be gridlocked even if every car is self driving. I'm not sure if the Bay Area is at that point yet, but NYC certainly is, as are most of the major cities of the world.

Hopefully Uber/Lyft start a van/bulk transit service. This would help reduce traffic by combining trips while being more efficient than buses because the server can dynamically route the driver to optimize pickups and departures. Perhaps even adding discounts for riders willing to trek the last mile on foot.

Then why isn't that being done today? As you increase the number of passengers, the cost of the driver becomes relatively trivial. It seems as if this were a service people were willing to pay for these money-losing companies are missing a significant market opportunity. I know there's UberPool but as far as I can tell it isn't a wildly popular option.

Re: Electric cars: The death of the internal combustion engine

#79

Post by searine »

pilom wrote: post #36

US drivers drive 3.1 Trillions miles per year [0]. Every month, the 12 Month moving average has been going up at 5 billion miles [0]. So every month we need to install enough charging stations to charge 5 billion miles/year. Lets use a Level 2 charger that adds ~25 miles of charge per hour. So 5B miles / 25 miles of charge per hour / 24 hours per day / 365 days per year = about 23,000 Level 2 chargers need to be adde…

98% of all charging on my car is done at home, at night.

Charging stations are for long trips or connivence at points of interest.

Re: Electric cars: The death of the internal combustion engine

#80

Post by stcredzero »

bryanlarsen wrote: post #2

Anytime you make something cheaper, easier to use, more useful and/or more efficient you get an increase in usage. Autonomous electric cars are all 4, and will lead to a dramatic increase in the number of miles driven. Some of those miles we can imagine (for instance sending your car on a dead-head journey somewhere for somebody else to use it), but most of the increase will probably be from new usage models that we…

it's not going to be the utopia that people here seem to expect

Look for the emergent problems. It's the insightful thinker who can observe cars then predict strip malls and parking lots. It's the emergent problems which will point the way to new disruptive business opportunities.

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