Green energy is already being encouraged by massive tax subsidies. This fee aspect is road maintenance. Different thing in my eyes.
5/31/2013 10:53:17 AM
5/31/2013 10:56:52 AM
[Edited on May 31, 2013 at 11:15 AM. Reason : i'm not sure how that double post happened]
5/31/2013 11:12:25 AM
5/31/2013 11:13:52 AM
I'm just going point out that the demand for pretty much every commodity has increased over time. The idea that the demand for gasoline will decrease is definately flawed.
5/31/2013 11:20:48 AM
Well if it does then everyone will flock to EVs, just as you want. So what's the problem?
5/31/2013 11:21:54 AM
Only about half of that petroleum is used to make gasoline, and a percentage of that is used in cars, I would bet that worldwide that other half's usage would make up for the adoption of electric cars, especially seeing as how slow you want that adoption to go.[Edited on May 31, 2013 at 11:31 AM. Reason : ]
5/31/2013 11:29:40 AM
5/31/2013 11:36:05 AM
5/31/2013 12:59:45 PM
5/31/2013 2:38:20 PM
I don't have the picture now, but I remember in some oil company presentation they showed a picture of a CNG 18-wheeler truck.Basically, you take the cab and double the size. Yes, that's how big the problem of fuel energy density is. Even if you do that, it won't have the same range. If you engineer to full range, then you're eating up a large fraction of the space for the cargo.It's not as big of a deal with cars because the gas tank isn't that huge by comparison. This isn't an argument against all transportation applications of NG. The fuel is cheaper, this is true. But the Picken's Plan had this huge gaping hole in it and it wasn't often mentioned.EDIT: but some people are working on super high compression of NG. this would make the tanks smaller.[Edited on May 31, 2013 at 2:45 PM. Reason : ]
5/31/2013 2:45:14 PM
5/31/2013 2:49:37 PM
5/31/2013 3:12:43 PM
Oh no doubt, I wasn't intending to make a case against electric cars, but that aspect of it is often forgotten by people.
5/31/2013 3:16:13 PM
My understanding is that most of the efficiency benefit of electric cars come from the fact that they don't have to burn energy at all times.So, the net conversion efficiency for an ICE may be 20%, but that's only under the best conditions of continuous driving. So the gap between gasoline and electric is greatest for city driving, and hybrids can bridge some of this.
5/31/2013 3:50:47 PM
It's also an infrastructure advantage. We don't know where the next generation in energy production will come, but whether it's solar, nuclear, or whatever, the electric car will work with it.
5/31/2013 3:52:18 PM
I drove a van for Raleigh Parks and Rec to pick up kids for the after school program a decade ago that ran on Natural Gas. That shit took like 15 minutes to refuel and the range was terrible.
5/31/2013 4:03:40 PM
^ these are the precise reasons it's nigh impossible to beat gasoline. It's outstanding for convenience, you'll never beat it. You need a big price differential to make up for that.
5/31/2013 4:24:18 PM
6/17/2013 9:14:31 PM
it depends on how you define efficiency. is it CO2/SO2/particulate/Hg emitted per mile driven? is it the amount of mechanical work done divided by the total amount of energy in the gasoline and coal? what sort of emissions controls is our hypothetical coal-fired power plant equipped with? or maybe we charged on-peak and the power company was running peaker combustion turbines. or maybe they have a lot of combined cycle generation. are the CC units equipped with selective catalytic reduction equipment? we also forgot to factor in transportation of gasoline via transfer truck and coal via rail and gas via pipeline.it's not nearly as simple as you made it out to be. try putting some damn numbers in there.
6/17/2013 10:04:09 PM
^^ furthermore, you have to look at the actual efficiency values of mass production energy versus small productioni'm not an engineer, so i won't pretend to know what those values are, but it has always been my understanding that energy production in large quantities (ie. power plants) is considerably more efficient than production in small (ie. car engines)...you might have more opportunities for energy loss in the former, but the latter is less efficient overallyou also have to take into account the source of the energy (coal, nuclear, oil, etc)...if you use more domestic product, you use less energy shipping the fuel from its source to the plantthere are so many things that go into calculating "efficiency" it that it's a bit disingenuous to break it down to loss from heat transfer
6/18/2013 8:37:57 AM
^everything I've read on this subject agrees with you Quag; that the power creation at the plant is more efficient.
6/18/2013 8:50:12 AM
yeah the efficiency of large-scale power production is much better than the efficiency of gas powered vehicles. and yes, there are a LOT of things to factor into overall efficiency.
6/18/2013 9:00:28 AM
Plus that is assuming a worse case scenario for CO2 output via a coal plant. There is obviously a mix of different power production in play at any time. As of 2011, NC generated half of its power from coal burning. So if you live in NC, you would have to cut in half the CO2 output from coal production, as half of the power that charges your electric vehicle is from nuclear, hydro, or another source that produces little or no CO2 emissions.
6/18/2013 9:29:54 AM
I avoid this rabbit hole whenever possible when I discuss electric vehicles. I hate hate hate having to defend the green nature of these cars. Its just an endless debate.
6/18/2013 10:24:03 AM
^^I'm not sure why you're focusing on CO2 here.Reasons for an EV:-lower commuting costs-reduces dependence on foreign energy sources-"latest and greatest" / early adopter-eliminates end user tailpipe pollution :SOx, NOx, CO-reduces CO2 footprint (questionable)
6/18/2013 12:35:50 PM
Well there are three ways to look at it. How much power has to be generated to charge a battery to travel x miles down the road, versus using an efficient gasoline engine to drive said vehicle x miles down the road. Secondly, if you are more concerned with greenhouse emissions, how much CO2 comes out of the tailpipe for said trip, versus how much is emitted from the very power sources that generate the electricity used to charge that battery. Finally you could go for the price of gas versus price of power.[Edited on June 18, 2013 at 1:50 PM. Reason : ]
6/18/2013 1:48:17 PM
residential electric energy from duke energy progress is currently at $0.0956/kWha gallon of gasoline generates 115k BTUs (34 kWh) and costs, say, $3.50/gallon (so $0.103/kWh)so even if everything else were equal (namely the amount of pollution generated per kWh used), you still have to take into account that an electric car is roughly 3 times as efficient (it can go 3 times the distance per kWh) as an efficient passenger caras i said earlier, i'm not an engineer, nor do i have any sources that definitively say that power plants pollute less per kWh produced...i'm fairly certain that's true, but i'll entertain any evidence to the contraryas i see it, EV/hybrid cars are inarguably more efficient...sure, they cost more up front, they weigh more than their petrol counterparts, and EVs are downright useless for anything outside of a short daily commute...they're not for everyone for any number of reasons, but if you compare apples to apples, they come out ahead
6/18/2013 3:02:47 PM
6/18/2013 3:39:28 PM
6/18/2013 4:39:18 PM
These are off the cuff calculations. I spent about 20min putting this together, it is by no means definitive and doesn’t prove anything. Its just my rationalization that electric cars really aren’t much better at saving fossil fuels. Perhaps if the majority of American energy came from nuclear then things would be different. Assume the energy used to harvest/transport/refine coal and gas are the similar. I know that they are not the same, but this simplifies the comparison tremendously.Coal plant ~ 35% Efficiency http://www.brighthubengineering.com/power-plants/72369-compare-the-efficiency-of-different-power-plants/ Power line transmission ~95% Efficiencyhttp://en.wikipedia.org/wiki/Electric_power_transmission Charge/discharge of Li-ion batteries ~ 85% Efficiencyhttp://large.stanford.edu/courses/2010/ph240/sun1/ Electric Motor ~90% Efficiencyhttp://www.energywise.govt.nz/your-vehicle/new-technologies/electric-vehicles Assume 1 unit of coal1 * 35% * 85% * 95% * 90% = 25% Gasoline Engine ~ 27% Efficiency https://en.wikipedia.org/wiki/Engine_efficiency Assume 1 unit of Gasoline1 * 27% = 27%
6/18/2013 9:59:03 PM
Hoff, you actually make the case that electric cars ARE more efficient. Since power grids are diverse, and coal is a mixture, EV efficiency only goes up from your number. What is the power generation efficiency of nuclear and natural gas?In any event, efficiency isn't a huge factor. We want diversification away from oil, and given that electric cars can take power from any generated source, it fixes the problems with being tied to a single source fuel. [Edited on June 18, 2013 at 10:50 PM. Reason : .]
6/18/2013 10:43:12 PM
Looking at NC, our energy generation mix is about 60% fossil fuels (coal & natural gas) and 40% renewable. http://www.eia.gov/state/?sid=NC#tabs-4Taking this into account, it does look like electric vehicles are better for the environment. I didn't realize our energy mix was as heavy on renewables. I stand corrected.
6/18/2013 11:24:35 PM
good info in here
6/19/2013 12:45:29 PM
You are counting nuclear reactors as renewable?
6/19/2013 12:55:00 PM
I'd lean more towards the renewable side with that than the fossil fuel side
6/19/2013 1:10:58 PM
6/19/2013 1:41:04 PM
6/19/2013 3:31:32 PM
6/19/2013 4:32:08 PM