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Hilo gas prices continue to fall
#91
Beleive it or not your condescending and sarcastic attitude is not all that entertaining.

Since your main gripe (you posted at length twice) about electric cars seemed to be its efficiency and fuel cost problems, my points were that in MOST cases electric beats gas powered cars in efficiency and cost to fuel (even well to wheels efficiency and even in disadvantageous situations such as present day Hawaii). I mentioned Virginia mainly just for sh##s and giggles and to show the other end of the spectrum. In places such as Virginia ELECTRIC CARS WIN BY A LARGE MARGIN. Again we're only talking about efficiency and fuel cost.

Now if you want to move the goalpost and discuss the dirtiness of coal or some of the other problems with electric cars (purchase price, battery costs, range, charge times etc.), these are real concerns and the case for electric cars at their current evolutionary stage becomes weaker. We would probably agree on MOST of the electric cars disadvantages.

1.But it still wins (in all but the most extreme cases such as present day Hawaii) in well to wheels efficiency.

2.And it wins by a HUGE margin in a "fuel to wheels" efficiency comparison(efficiency of the entire vehicle itself including charger losses, battery charge/discharge losses, motor losses). GAS= 20%, ELECTRIC= 65%

Do you at least agree with these two main points???

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#92
Charles....

First off... I find his tude quite funny...

second.. I do not believe you numbers will ever work going from oil to electric with the miles of transmission and the conversions needed to charge up a car. Maybe someday with nuclear power plants they will work out.
Even if you use natural gas or coal for generating the electricity, it might be cheaper, but not more efficient as far as the energy released vs used.

Right now all the stats out there are hocus pocus anyway, if electric was better they would be out selling everything.

Tesla Motors has the best idea, Make an electric car that blows the doors off the other sports cars out there... Next we need a National Electric Hotrod Association to step up and create a drag league and a National Association for Electric Stock Car Auto Racing.

then you would see some real improvement on battery and power conversion.


NASCAR

Transplanted Texan
"I am here to chew bubble gum and kick some *** ... and I'm all out of bubble gum"
-----------------------------------------------------------
I do not believe that America is better than everybody else...
America "IS" everybody else.
The Wilder Side Of Hawaii
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#93
Don't believe me.

The numbers are on the web and verifiable. You don't need to think about "miles of transmission"...they can be disregarded because I'm using the price of electricity. The cost due to "miles of transmission" is already factored into the price of electrcity at your home outlet.

So to estimate the cost for fuel (electricity) to operate an electric car you need:

1.cost of electricity
2.amount of it you pull off the grid
3. miles driven

you can calculate cost per mile for the electric car and directly compare with a gasoline car cost per mile as I have previosuly done.



As to the fuel to wheels efficiency comparison its very straight forward. Conversions (efficiencies) needed to charge and run the car are charger 85%, battery efficiency (thermal losses) 85%, motor efficiency 85%.

So ELECTRIC is 85%x85%x85%= 61%

Gasoline engine 25%, transmission 90%.

So GASOLINE is 25%x90%= 22%

61 percent beats 22 percent. This is not Hocus Pocus its just math.
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#94
Do you realize when you say a 9KW vehicle you're talking about a perhaps 15 horsepower gas motor? In other words, a motorcycle engine, and a little bitty one, which would get close to 200 mpg already. It's very important to compare like to like.

Esnap is dead right. Electricity isn't a quarter of as efficient as straight up petrol.
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#95
JWFITZ:


Maybe you are thinking of energy DENSITY when saying "Electricity isn't a quarter of as efficient as straight up petrol."
In energy density gasoline beats BATTERIES. I Never said otherwise. But energy density should not be confused with energy efficiency. Energy density does not factor into the claims I have made.

An oversimplified way of understanding energy density vs. energy efficiency.

My gas car goes 300 miles on a tank of gas but its twin electric version only goes 150 miles on a full charge.

Thats ENERGY DENSITY. Gas car wins.

Same gas car takes 10 gallons (330kwh) of gas and costs $25 to go 300 miles but its twin electric version takes only 70kwh and cost only $8.40 (@ national average electric rates)to go 300 miles.

Thats ENERGY EFFICIENCY. ELECTRIC car wins.




As to the "9KW vehicle" you are talking about. I was referring to an electric vehicle using 9.1KWH of ENERGY to go 55 miles not the size of a motor or "vehicle".

The superiority of the electric car in FUEL to WHEELS EFFICIENCY is not an opinion, it is a FACT. Nearly three times more efficient.



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#96
Raw efficiency is not the only consideration. Every time you gas up fumes leak into the air. Usually, you drip some on the ground as well. It may not seem like a lot but multiply it by the millions of cars that fill up daily. Also factor in millions of poorly tuned and maintained ICE cars. Say what you will about HELCOs motives but they are forced to run their plants relatively cleanly. Gas stations also leak and pollute the ground water.
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#97
Charles,
I am sorry if I came off as having an Attitude,
Having an attitude would literally mean I have a biased belief, and that is the furthest thing from the truth.
I am completely agnostic, I have no belief. on any subject of science I only have one of the following, Knowledge, a theory, or ignorance.

Like I mentioned earlier, it is highly probable that if Helco were to get all of its power from some combination of Wind, Solar, and Geothermal, you electric bills would not be lower.

The reason is that there are inherent costs in all technologies..

When you start charging and discharging batteries you will quickly learn how expensive they are. The battery in your car last for years because it is never drained below 10%. As soon as your car starts your alternator tops it right back up.

If you were to let it run down to 90% below capacity, you could only get a few cycles from it.

So in order to have an electric car where the batteries will last, you will need to have allot of extra capacity. We know that battery capacity not only cost money (and enormous energy to initially manufacture and transport to market) batteries weight a lot. This is weight that you have to drive around with, and then ultimately replace as they wear out.
The batteries used for deep cycle applications give much better performance, but they are still subject to a depth of discharge/to number of cycle ratio.

There is a nitch where electric cars fit and perform fairly well and that is small cars that only need to go 20-30 miles between charge. if you augmented it some pv and lived in a very sunny place, all the better.

MarkP,
The problem of leaking hydrocarbons is much less horrible than people imagine.
Firstly the very study and design of hydrocarbons is called "Organic Chemistry". There are few things on Earth more natural, as they are of the earth.
Every day millions of barrels of crude oil seep naturally from cracks in the earth. This oil is naturally remediated by bacteria that thrive on it.

The problem of any concentration of one particular substance in any one place is as bad with gasoline as it is with butter, vinegar or Vitimin-C.

If a truck spilled 10,000 gallons any one of these things in one spot it would be just as polluted as if they spilled gasoline. But a little here or there is quickly consumed by oxidization, evaporation etc.

Back to cars, There is no doubt that the way we build and use cars is crazy.
If cars were built to be just big enough to do the job, we could save tons of fuel. But instead we buy these enormous behemoths with 300 hp engines (It's Nuts). We could have cars that have 25 hp turbo diesel engines with 8 speed transmissions that would burn clean and get amazing fuel economy. If we demanded these things, auto makers woud make them. But they don't because they make cars that will sell to a market of idiots that think style and form is more important than economy and function.

Just as crazy as our cars, is the way we used electricity in our homes. In Hawaii where most people do not need to heat or cool their homes it is possible to cut back to such a small electrical usage that a small .5-1Kw PV system would be plenty. But as long as we can flip a switch and buy small amounts of power from that evil Helco and don't take the responsibility and assume the initial expense of building our own system, we well always be the whipping boy of the public utility.

Conserve, conserve, conserve. Turn everything off except what you absolutly have to use at the time you use it.
Replace all your bulbs with 14 watt cfls, Wash dishes and some laundry buy hand. Do only one load of laundry per week. Get a front load washer. Line dry.
Wash your dishes by hand. Get a small 20-32 inch flat panel TV and only have it on when you use it.
Build your own solar water heater. If you already have an electric water heater, you can convert it for a bout 100 bucks into solar.
Get rid of the front opening refrigerator and replace it with a chest freezer with external thermostat. This will use the equivalent of a 100 watt bulb burned for 1 hour per day. That is less than 5 watts continuous.
Do all your cooking with gas. Throw away your electric rice cooker, toaster, coffee pot etc. use a pressure cooker for things like chicken (8 minutes) roast (fork tender in 40 minutes) Use a whistling tea pot and a French press for coffee. Use microwave only for reheating things.






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#98
The Plant to Wheels efficiency to my mind is nearly irrelevant, because a vehicle must store its fuel somehow and carry it. It's near as pointless as saying that the Hummer H3 is a very efficient vehicle because it has an amazingly efficient electric fuel pump. Perhaps the assertion of the point is purely academic, and if that is the case, I agree. In the context of vehicle design, "well to wheel" efficiency is the the most critically important concept. And even that one isn't a very good one, because new technologies must bear the inefficient start up costs of new infrastructure, as in a much more powerful transmission grid, charging stations and all the rest.

The answer isn't what we drive, it's driving less or not at all.
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#99
are you only trying to achieve a cost savings by going to electric? Or are you trying to save natural resources? Or reduce pollution?

The numbers can be massaged based on the goal in mind.

The only one that ever works though is cost savings for the end user. And right now, electric cars are not a cost saver for the masses.









Transplanted Texan
"I am here to chew bubble gum and kick some *** ... and I'm all out of bubble gum"
-----------------------------------------------------------
I do not believe that America is better than everybody else...
America "IS" everybody else.
The Wilder Side Of Hawaii
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$2.49 per gallon this morning in Hilo
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