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Comment Re:Your assumptions are skewed = strawman (Score 1) 504

stupid assumptions like losses being orders of magnitude higher than actually occurs.

Still beating this dead horse, I see. And I was over by about a factor of 2, not OOMs. Hell, you've fixated on a self-admitted mistake and not pointed out any others.

As for 'Arbitrary placing of goalposts' I'm wondering if we're speaking the same language. To make it clear: My 20% figure is not a 'goal', it's a statement of condition.
What I was trying to say earlier:
1. Transmission losses within a segment are negligible. My first post the asterisk marked footnote. Though I should have been stronger than 'probably'*
2. Most segments are basically single-use due to zoning and such. Housing is housing, commercial is commercial, industrial is industrial.
3. Due to #2, we can generally model a segment as a single unit(hardly having an home be an island!).
4. Most of the jump during the day in electricity use is from commercial and industrial. Home power usage tends to spike in the evening as people return home, cook dinner, and turn everything on. The peak doesn't match.
5. Power company transformers are around 99% efficient. Traveling segment to segment will probably hit at least 2 of them, resulting in 2% losses. By the same token, if you're shipping power from segment to segment, you're probably going to have to ship it even further because, on average, the neighboring segments will be the same time and thus producing excess power at the same time. 2 more transformers and a high voltage line later, you're at 3-5% losses.
6. I can't find the charts right now, but power usage during the day tends to be around 20% baseload for homes average about 20% of max during the day, while solar generation@100% of needed energy would put maximum generation at around 100% of maximum; thus the comment about not really needing to worry until more than 1 in 5 homes have significant solar installations.

*Though you'll probably take this as your next argument

If you really care about this topic and are not just using it as a vector to push your politics I suggest taking a look at wikipedia. There is no excuse for the ignorance you are trying to shove down people's throats.

You have yet to prove that anything I've said is incorrect. The one instance you keep harping on I realized myself and corrected. Wikipedia does not cover these topics in sufficient depth.

As for my politics, you've set up a HUGE strawman that you've been relentless in attacking. You have yet to identify a political belief I presumably hold accurately enough to pin down, other than I'm presumably some sort of corporate shill. All you should really get from the link is that I'm pro-gun/self defense.

Go ahead. I'll repeat: Which political party do you believe I'm a member of? Can you identify my standing on abortion and gay marriage, just to name two hot button topics? Go ahead. If you want the bonus round, see if you can avoid being insulting about it.

Something within a dozen miles may as well be next door so the electricity is being consumed almost adjacent to where it is being generated and it can be whatever load factor they guys in control rooms want it to be.

A dozen miles would be, depending on exact infrastructure, 3-5% loss rate. If you have something else, POST IT.
Transformers: 98-99% efficient. (Need at least 2)
Power line losses: Mostly in the 240V section, 1-2%.

I'm going to say: Put up or shut up. Stop beating the dead horse about power loss and identify some where else that I'm wrong, with some proof or at least logical reasoning.

Comment Re:Electric motor vs Gasoline Engine (Score 1) 398

Yeah, the GP's understanding is incorrect, to say the least. You're not going to get 400 hp performance out of a 50hp generator hooked up to an electric motor(even though that generator is probably producing 150hp of turning power in order to provide 50hp worth of electricity). It might help, but you're going to need a battery to provide ~200hp of power to make up the difference.

Still, I stand by my 'factor of 2' rule of thumb with acceleration. If you put as much effort into minimizing 0-60 times in an electric vehicle as has gone into the Mustang, you'd only need ~210 HP to match it. For example, the Tesla Roadster is 3.7 (248hp) and the Model S Performance is 3.9 with it's 416hp.
Weight makes a huge difference in 0-60 times of course - Model S is 4.6k pounds, Roadster is 2.7k, and the Mustang is 3.6k

The model S weighs 28% more, has 4 less hp*, and still manages to shave off 6/10ths of a second.

Going by what I'm seeing in other ways, it looks like both electric vehicles are limited by the battery's ability to deliver power. A Tesla with the smaller battery pack(making it lighter) takes longer to reach 60 than the larger pack.

One significant thing to realize is that the way engines and motors are generally rated vary. An engine is rated at it's maximum deliverable power. It can remain there ~100% of the time though as long as sufficient cooling exists. An electric motor is generally rated at the power it can deliver at 100% duty factor. Engines are generally limited by the ability to deliver fuel an air. Electric motors are generally limited by heat.

What does this amount to? If you can deliver the amps, it's possible to run electric motors at higher than their maximum rating. You lose some efficiency and risk burning the motor out, but there are motors out there that you can run at 200% for something like 1 minute. 300% for 10 seconds, stuff like that.

*Not really significant.

Comment Re:Your assumptions are skewed = strawman (Score 1) 504

Your assumptions are very skewed which is why I'm calling it a strawman.

It's not very much of a classical strawman then. It doesn't help that the one assumption you keep attacking was one I changed on my own.

Modelling the houses as islands when they are connected to the grid implies that you have a barrow to push or that you are far more stupid than is likely.

Isn't ignorance an option? Your island analogy has me puzzled, I'm trying to picture this in my head and correlate it with my words. I mean, in the posts I KNOW I've mentioned neighborhoods, transmission lines, and specifically segments where I thought it'd be obvious that multiple homes are hooked up to any given segment.

I certainly have barrows to push, but I've stayed away from them here. I haven't mentioned nuclear power at all until now, for example.

Ah yes, talking about a 10% loss in transmitting electricity to what is effectively next door in transmission scales even if it takes an hour to get there in traffic - are you SURE you looked up actual figures?

You do realize that you're beating a dead horse? I conceded that back in the SECOND post. You should now be attempting to argue against a 3% loss estimate.

Still, because you think it's so important, here's my thought process through this whole thing: I used 10kwh because it's a nice round number. Then to account for transmission losses, I subtracted 1, which amounts to a 10% loss. For the power company I knew it'd be a touch higher, but not that much higher, so I added 2 to 10 to get 12(12 produced, 10 delivered). I never bothered to figure out that percentage(17%, ouch!). That didn't quite sound right to myself in the second post when I actually figured out the percentages, so I looked up average losses. 7% for the grid means that 'most' runs should be substantially below that, but I also figure that long distance/high voltage/wattage runs are specifically designed to be highly efficient it it should only be a couple percent. Ergo, 3-5%, better than average, but still a factor to consider.

To me it just looks like no holds barred Red on Green political action with a few technical sounding guesses (which you are probably very much aware are not correct) to try to make it look like it's not just an outright lie.

Umm... Wow. Do you also scream racism when somebody says they like fried chicken?

'd rather this place remained a technical discussion site of a sort instead of a political rant site.

Huh. If you know so much about me and my politics, let's give you a little test: What political party am I?

Finally - For a person who's worked in the power industry you seem long on rants and short on facts. It should be simple enough to explain where I'm wrong with a couple citations.

For example, one figure I've posted multiple times is that generated power shouldn't really be leaving the segment until solar accounts for more than roughly 20% of the power usage of the homes on the segment. IE if there's a 100 homes on the segment that more than 20% of them would need to install solar matching 100% of their net needs before you start getting significant enough backfeed on the segment to have to worry about efficiently transporting said power to other segments. I also stated that different regions would vary.

What do you think about this statement?

Comment Tesla maintenance fees (Score 1) 398

First, not an owner, if you're looking to purchase I suggest doing your own research.

1. No the fees aren't necessary. For one, federal law interferes.
2. Good luck shutting all those radios off and keeping a functional car.
3. OTA updates have improved the car quite a bit, so stopping that isn't necessarily a good idea.
4. The fee actually covers a huge amount of work, it's probably worth it.

Comment Re:The optimal way (Score 1) 504

But maintenance costs are forever, and if the owner of some far-flung cabin can't bear the full cost of maintaining a line that serves no one else, that line never should have been built in the first place.

I do have concern about such a system causing a sort of deflation in electrical provision though. IE customer A is the end point, and frustrated by maintenance costs he cuts his connection. Now suddenly B is the last segment, and A wasn't that much further away, and now he's bearing increased cost due to A leaving. So he leaves. Next thing you know the whole neighborhood is leaving...

By keeping maintenance costs more even to the customers, you encourage keeping enough clients around to have economy of scale.

Oh, and I probably should have mentioned that when it comes to business; 'hard' generally translates to 'expensive'.

Comment Electric motor vs Gasoline Engine (Score 1) 398

You do realize that you're putting up a 420 horsepower engine up against the 145 HP motor in a volt? It also looks like they've gotten better with the volt:
Chevy volt: 8.9
Ford Mustang: 4.5

Electric motors are good, but they're only about twice as good as their horsepower rating would imply up against a gasoline engine, much less one optimized for 0-60 times.

Comment Re:X Miles IS a standard for me (Score 1) 398

I have no interest in a 50 HP car, nor do most US buyers. Not useful.

It only takes about 15 hp to keep a car at highway speeds. 50hp would really be overkill. That might be enough to keep a semi going on the highway...

Then you put a 100(leaf)-300(Model S) electric motor in it, which given the RPM range of electric motors combined with the whole '100% torque at 0 RPM' means that, no matter the horsepower, electric vehicles tend to be very 'zippy' up to almost their max speed.

Comment Re:The optimal way (Score 1) 504

You've presented two extremes, and neither represents the most fair and accurate way to allocate maintenence costs.

Charging the last guy everything was NOT my idea, it's what motivated me enough to post counter-points, and I presented more than just 2 options.

The most fair and accurate way is to look at who is served by each segment of the line.

Better stated than what I proposed. It's a bit like 'you pay for your segment, your neighbors pay for theirs'. The problem I see with it is that while it's 'fair and accurate' it is very much 'not easy'. 'Easy' while being 'more fair' is a legitimate option, where outside of specific edge cases you simply charge everybody some sort of average for costs.

but the 1000th customer wants to build a home 100 miles from that cluster, the utility will never recover the cost of that extremely long line extension if the single customer it serves is permitted to pay "average" rates.

I forget the name of the act, but there's actual federal subsidies to pay for that line(and more people tend to move there over time), but failing that he doesn't get coverage.

Comment Re:X Miles IS a standard for me (Score 1) 398

Hybrids don't pay for themselves in increased efficiency unless you drive them something like 300,000 miles.

It depends on your usage. When I first started doing the calculations I quickly realized that hybrids only really made sense for intense city drivers. 'NYC Cab driver' was an ideal case for them.

However, I think that the break-even point is a lot sooner today than it was 5 years ago. It started at 10 years/150k miles for 'standard' usage, but today Hybrids are generally only ~$3k over an equivalent standard engine vehicle.

I like to use Honda Civics due to the similarity - 33mpg vs 45 mpg(combined). $22.7k vs $24.6k*. $1.9k price difference comparably equipped.

At 15k miles/year(average), that's 121 gallons saved a year. At gasbuddy's price of $3.64 average, that saves $441 a year. Payoff would be in 4.3 years, or 65k miles. Less if you do lots of city driving. Far short of your 'something like 300k miles'.

Look at it like Europeans - gallons per 1k miles.
Hybrid - Standard - difference
highway: 21.3, 25.6, 4.3 gallons saved per 1k miles
city: 22.7, 33.3, 10.6 gallons saved per 1k miles.

If you drive highways, TDI does makes far more sense though.

Comment Re:X Miles IS a standard for me (Score 1) 398

That was a few years and he was getting around 85 miles on a 2 gal tank.

Just over 40 mpg in a vehicle the size of a VW isn't great gas mileage.

As you mention, the power demands for a vehicle is indeed different than a locomotive. The locomotive doesn't stop anywhere near often enough to bother with regenerative braking, for example.

With standard hybrid vehicles batteries pay for themselves in increased efficiency, thus getting rid of them isn't smart.

as if somehow generating the electricity to charge the batteries doesn't

Depends on the grid you're charging from. Plus, average power line losses are only 7%, and power plants can be up to 40% efficient - gasoline engines are generally lucky to reach 30%. Plus pollution controls are more effective(on an energy basis) for the fixed plant.

Comment Re:what happens when the batters wears out? (Score 1) 398

Tesla charges $600 a year because they know their owners can afford it, not because it (or any other service) is "worth" that price tag.

It's $600/year or 12,500 miles, whichever comes first, but you can buy a '4-year plan' that covers 4 years/50k miles for $1900, which is a substantial discount.

I actually think it's a pretty good deal given that it includes 'hardware upgrades' like the new shield talked about a few weeks ago...

Comment Re:X Miles IS a standard for me (Score 1) 398

The second comment is about the generator. From the sound of it you want that so you can recharge the battery. However, a small portable generator can run all day on a couple of gallons of fuel. Why not skip the batteries all together and have the output power the electric motor.

It's done with trains today -diesel electrics don't have significant battery capacity(they're starter batteries like in normal cars, just scaled up for the needs of the diesel engines). The problem is that the narrower the range you need on your engine, the more efficiently you can design it. That includes both rotation rate AND power.

Power demand for a car is too variable to be able to really miniaturize the engine much. That's why hybrids save gas - they use the relatively enormous power delivery* batteries are capable to smooth the peaks, enabling the engine to run in it's ideal zone more, saving gas, then regenerative braking saves even more energy by storing stopping power back in the batteries.

When you start shifting to strong EV type operations, you shrink the engine even more into a 'range extender' where you don't need it to provide much power at all, it's just there to convert the extremely good energy storage system gasoline/diesel represents into kwh as efficiently as powerful, even if it's only 40kw** or so. As mentioned, if the batteries are too low, the thing can keep chugging away even while the car is parked. Think about camping - Not only does it top off the batteries overnight, it could also provide enough power to run some electric stuff like lighting or even a TV.

Though I question whether such a system(gas tank, fuel mass, engine weight/space) would actually be lighter than 'more batteries' at this point, as Tesla demonstrates.

Hell, I've seen proposals for small generator-trailers that provide electricity while on the move along with more cargo space for those long trips.

*For a short period of time, at least
**This is more than enough power to travel at highway speeds for most vehicles.

Comment Re:Animal cruelty? (Score 1) 204

Oh, you're talking about horses? Are they food-grade horses?

Define food grade? I know the USA shipped slaughtered horses to Europe for consumption for quite some time, including former work horses bought at auction and such, but at the same time I know that regulations have tightened since then.

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