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Jun 22, 2011, 09:32 #14
- Join Date
- Nov 2009
- Keene, NH
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The first one explains what the topic is, and the mechanical reasoning behind how certain engines deliver peak power to fuel consumed at certain RPM's....
The second one lists where power generation in America comes from with all those pesky percentages I've been saying (+/-1%) about where electricity COMES FROM.
The third discusses the infrastructure of electrical generation, mentions the 7% line loss (though oddly the parts about substation loss are missing now), etc, etc...
As for it being wikipedia, that's why you check the REFERENCES listed at the bottom. -- and why I said "excuse the truthiness" (that's a joke... you didn't get it)
'cause it sounds like those are alien concepts to you.
Either that or the -10F nights and 40F+ days of December through February here color my opinion on the efficiency of electricity as a heat source... or should I say the complete lack therein. (of course we have 40 to 50 degree temperature swings for 9 months of the year so... Real fun when it's the pneumonia inducing 70 degree days and 20 degree nights -- hell it was 80F here yesterday and got down to 38 overnight -- in JUNE... thankfully it's a nice 64F today, but that probably means near freezing tonight meaning I'm turning the heat on IN JUNE one day after running the air conditioner)
But sure, lets go to something with some meat, that pdf.
First off, notice they ALWAYS relate it to a barrel of crude -- yet, only only 48% of a barrel typically becomes gasoline -- by using the full barrel and not including the practical energy use produced by the rest of it, they're able to skew the numbers for gasoline by over 50% in their favor. Watch out for that particular lie by omission, it's used a LOT.
They flat out omit where the calculations of transmission are, and simply state their numbers -- said numbers fluctuating as much as 50% depending on geography. (see why natural gas here costs 40% more than what #2 heating oil does by usage). It's why their cherry picking fuel sources throws all their figures into doubt.
They literally chose the best fuel in terms of recovery/processing cost (97.5% by their numbers), the best in terms of generation (GE H-System) which is 60% -- by their own numbers the well to outlet efficiency is 52.5% total using the "perfect fuel" that isn't available everywhere and/or is impractical in many climes. They may as well have listed hydroelectric for all the good those numbers mean to someone on the US East Coast. (though sure, West Coast that makes a bit more sense)
If you go down to figure 3 on this page:
Electric Power Monthly
... and it's easy to see why Natural Gas is an also ran -- for all it's highly vaunted "efficiency" it costs twice as much because it's four times harder to get and find... Also explains why for all the *****ing about petroleum, in the US power generation world it's less than 1% of the source. (all THREE plants -- two in Massachusetts, one in Maine).
As anyone working in the electricity generation field will tell you -- until something better comes along, coal is king... because it's cheap, not because it's efficient.
So let's talk burning coal.... which has HALF the efficiency of natural gas at the plant. Food luck finding concrete numbers on coal though, it's a tight lipped secret as to how the efficiency of coal burning... well, efficiency isn't a word used in such discussions.
Analysis: Efficiency of coal-fired power stations
Power Plant Efficiency Hasn't Improved Since 1957 – CleanTechnica: Cleantech innovation news and views
Neither being what I'd call trustworthy or citing their sources -- but the numbers are inline with what I've heard in the past.
If we plug 33% "at the plant" into their figures replacing their ideal perfect world natural gas 60%, that well to outlet efficiency drops from 52.5% to 33%*92%*97.5%*97.5% == 29%... and that's assuming a ground to plant efficiency on coal that's the same as natural gas -- which is 100% fantasy-land given the cost of getting coal out of the ground in manpower and energy required of mining vs. drilling. I can't even find numbers on that anywhere, but I very much doubt that mine to power plant sees the 97.5% recovery efficiency well to plant sees for natural gas.
Of course that doesn't even talk the pollution side of things... natural gas, diesel and gasoline are clean fuels compared to normal coal burning thanks to Sulfur Dioxide.
Coal power in the United States - Wikipedia, the free encyclopedia
Check it out... dirtiest plant in the nation pushes out 40 pounds of SO2/MWh.... the national average is much lower around 6 pounds per MWH, but compared to... well...
Fossil fuel power station - Wikipedia, the free encyclopedia
Nice little chart there showing the emissions based on energy use. Brown coal, the most commonly used is the dirtiest of fuels ESPECIALLY in terms of particulates.... hard coal isn't a whole lot better -- while you can see natural gas' numbers are HALF on Carbon dioxide and Nitrogen Oxides, and by comparison non-existant in terms of Sulfur dioxide and methane compounds... and particulate? WHAT PARTICULATE?
Of course, then you have your "clean coal" whackjobs -- who are a bit like the car emission standards whacko's in commiefornia... the process of cleaning the emissions reduces the delivered power so much, you end up burning more fuel resulting in another zero-distribution... or worse, exacerbating the problem. The most recent California emissions standards sure knock another 3% off the exhaust of gas powered vehicles from the previous standard, but it costs 5% fuel efficiency to implement meaning you're burning 5% more fuel to go the same distance. They talk about pollution per gallon burned when they should be talking pollution per mile traveled... which again is the classic propaganda technique of card stacking in action. The whole "clean coal" thing takes and already inefficient and dirty (but cheap) process, and triples the operating costs, involves the costs of building new facilities (in a country where 90% of the power facilities were built before 1975) and worse, decreases the already low mine to outlet efficiency... To the point some think it might be more efficient to convert to burning #2 and #4 oils instead of "clean coal" (especially since with biofuels #2 and #4 oils can have a non-fossil renewable source)
Which is why Tesla's choosing something that was only 20% of the supply source in what are basically glorified advertising materials -- one that is impractical and overly expensive to implement in most places, and is the cleanest burning of the natural fuels is card stacking! If they had averaged based on the national (or better world) costs from ground to outlet, I'd take their numbers seriously -- but cherry picking the perfect fuel source is little more than the classical propaganda lie by omission.
Well, to be fair they didn't cherry pick the fuel source that REALLY would have skewed the numbers -- but that one would have been too obvious given it means next to nothing if you don't live within 100 miles of the Colorado river.
That PDF is funny though as it is filled end to end with card stacking to give the pseudo-science eco-nuts something to get wood over (Teak? Mahogany? Ebony? Don't worry, just **** with you padre!) while barely mentioning a point that made my eyeballs bug out.
COST... They're claiming 110 watt/hours a kilometer (DOUBLE what I last heard for a EV); That's 178 watt hours a mile!!! HOLY HANNAH!!! (I'm saying that in an impressed/good way!)
Using the classic "270 mile" range figure most of your sources like to pimp as a practical range for a vehicle (heck, it's even in their fictitious but well crafted "plain folks" sidebar in that PDF) that works out to 48KW/h... which by my last electric bill (16.9 cents/kwh by the time all the taxes and supplier charges are tacked on) works out to $8.10 cents... Using the uber-efficient hybrid 63mpg Honda Insight using their numbers, that's 4.2 gallons worth of gas -- at four bucks a gallon right now that's basically 17 bucks worth of fuel.
Meaning the Tesla costs less than HALF to operate per mile than the most efficient hybrid on the market. Figure it out for the average 30mpg highway road car and that's 9 gallons of fuel [/i](which is EXACTLY where the 270 figure originated -- 3/4ths of a tank on a typical road car -- 10 gallon + 2 reserve)[/i] or a $36 fillup.
Hmm... $8 or $36 dollars to cover the same distance. Gee, let me think. Over 400% the FINANCIAL efficiency of a road car. TO HELL with it's environmental impact, there's your selling point!!! Rather than lying by omission about how "green" their electric is, they should be trumpeting that from rooftops. Given the average commuter travel of 32 miles (16 each way) every weekday, that's 8000 miles a year meaning compared to what's on the road for most people now... that's $1040 in gasoline vs. $231 on your electric bill... basically $809 a year extra back in your pocket.
But of course, this is why most hybrid owners want to plug into the grid even with cars that don't come with a plug. It's one of the most popular after-market mods for first and 2nd gen Toyola Pious', FINALLY looking to be offered on the 3rd gen.
So environmentally with the current power infrastructure -- NO. It's no better and they're card stacking their numbers by basing it on natural gas. In terms of your pocket however... But then I've always been a fan of anything that speaks to my wallet.