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How many gallons of gasoline would it take to charge an iPhone?

exxonmobilperspectives.com

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Re: How many gallons of gasoline would it take to charge an iPhone?

#31

Post by baggachipz »

soren_dahl wrote: post #22
baggachipz wrote: post #17

That's odd, they neglect to mention the true cost of gasoline; both in subsidies used to keep it cheap at the pump, as well as the environmental cost associated with cleaning up their profit-generating mess. ETA: Point out an oil company's dishonesty, get downvoted. Only on HN.

US pump prices are low because you don't tax it like other countries, that's not a subsidy. Environmental cost? I'll grant you that accidents involving rigs and shipping are spectacular and locally devastating when they happen, but what about the pros of a cheap and relatively easy fuel, it has saved millions of lives. To give some balance what about farming? Farming has devastated the environment on a global scale.…

It would be a fair trade, but your whataboutery didn't include the true subsidies (http://en.wikipedia.org/wiki/Energy_subsidies) as well as the much larger environmental cost: CO2 production from burning fossil fuels. It's going to cost a lot to clean that up, and I sincerely doubt that ExxonMobil or their brethren are going to foot that bill.

Re: How many gallons of gasoline would it take to charge an iPhone?

#33

Post by soren_dahl »

baggachipz wrote: post #31
soren_dahl wrote: post #22

Earlier quoted context omitted.

US pump prices are low because you don't tax it like other countries, that's not a subsidy. Environmental cost? I'll grant you that accidents involving rigs and shipping are spectacular and locally devastating when they happen, but what about the pros of a cheap and relatively easy fuel, it has saved millions of lives. To give some balance what about farming? Farming has devastated the environment on a global scale.…

It would be a fair trade, but your whataboutery didn't include the true subsidies ( http://en.wikipedia.org/wiki/Energy_subsidies ) as well as the much larger environmental cost: CO2 production from burning fossil fuels. It's going to cost a lot to clean that up, and I sincerely doubt that ExxonMobil or their brethren are going to foot that bill.

I read the wikipedia link, it seemed inconclusive. Fossil fuel subsides are less than that of renewables (unless I am reading the article wrong) and that's a 1-1 comparison, fossil fuel must utterly dwarf renewable in terms of revenue.

I'm not saying that big (or small) oil is innocent by any means, personally I believe the problem lies with the political side of it, but certainly I don't think the basics of oil extraction and delivery deserve the rep they currently have.

And on farming, how much carbon do you think farmers released into the atmosphere burning the trees and scrubs that stood in the way of the farmland? Not to mention the damage done to the hydrosphere?

You might like this by the way, if you haven't already read it: http://harpers.org/archive/2004/02/0079915

Re: How many gallons of gasoline would it take to charge an iPhone?

#34

Post by bhousel »

frankus wrote: post #23

Petroleum is really frickin' energy-dense (leaving aside the fact that unless you're heating something only a small fraction can be turned into useful work). A mid-range home EV charger peaks out at about 20kW. By contrast, the energy flux of a gas pump is around 20MW.

A mid-range home EV charger (like the GE WattStation), is spec'ed for 30A at 240V, which is 7.2kW, not 20kW.

You might be confused because a typical battery in an EV is around 20+kWh, which is why it takes a few hours for the wall charger to charge it!

For comparison, a 20kW load would draw 83A at 240V. A smallish pole mounted utility transformer may supply 20kW.

Of course, none of it detracts from your point that petroleum is very energy dense :)

Re: How many gallons of gasoline would it take to charge an iPhone?

#35

Post by liber8 »

baggachipz wrote: post #31
soren_dahl wrote: post #22

Earlier quoted context omitted.

US pump prices are low because you don't tax it like other countries, that's not a subsidy. Environmental cost? I'll grant you that accidents involving rigs and shipping are spectacular and locally devastating when they happen, but what about the pros of a cheap and relatively easy fuel, it has saved millions of lives. To give some balance what about farming? Farming has devastated the environment on a global scale.…

It would be a fair trade, but your whataboutery didn't include the true subsidies ( http://en.wikipedia.org/wiki/Energy_subsidies ) as well as the much larger environmental cost: CO2 production from burning fossil fuels. It's going to cost a lot to clean that up, and I sincerely doubt that ExxonMobil or their brethren are going to foot that bill.

What "true subsidies" are you referring to? The link you cite to doesn't really mention any. The three biggest fossil fuel subsidies listed are:

Foreign tax credit ($15.3 billion), the Credit for production of non-conventional fuels ($14.1 billion), and the Oil and Gas exploration and development expensing ($7.1 billion).

The first and third are deductions just about every global corporation gets. The second one appears to be subsidizing alternative fuels, not fossil fuels at all.

Re: How many gallons of gasoline would it take to charge an iPhone?

#36

Post by wickedchicken »

Gas has an incredible amount of energy density. You can do a fun calculation as follows:

If you believe this calculator, it takes 2419kJ to go 20km while cycling. (http://www.tribology-abc.com/calculators/cycling.htm)

A gallon of gas contains about 114,000BTU (http://en.wikipedia.org/wiki/Gasoline_gallon_equivalent). Note that the Exxon diagram is 'per fillup' not per gallon.

So... http://www.wolframalpha.com/input/?i=%281%2F%28%282419kJ%2F2... yields 617MPG while biking.

It's approximate, but good to know that biking is roughly an order of magnitude more efficient than cars.

Re: How many gallons of gasoline would it take to charge an iPhone?

#37

Post by GFischer »

guptaneil wrote: post #27
Aqua_Geek wrote: post #19

Earlier quoted context omitted.

> If you want a vehicle that is large enough to hold a human and can push air out of the way at 60 mph But do we really need to go 60 mph? Vehicles seem to be optimized for less-common use cases (e.g. 5 people in the car traveling 60 mph) instead of their more common uses (e.g. one person commuting at 30-40 mph). I, for one, would like to see smaller vehicles - NOT SmartCars and the like but an actual rethinking of t…

I suppose this depends on where you live, but going above 60mph is normal usage for me. In fact, a minimum speed limit of 45mph on freeways is fairly common (unless you can't due to traffic, of course).

On the other hand, I've never been able to drive above 45 mph on my normal commute, I'm only able to do so when I go on holidays.

Some cities are just not planned for cars (European cities like Vienna for example, where you cannot enter the downtown, or some South American cities like Montevideo).

I used to have a Maruti car and it was plenty for 99% of the time, and I'd buy a low-range electric/hydrogen/whatever car if it was cheap and offered me a better mileage equivalent.

Re: How many gallons of gasoline would it take to charge an iPhone?

#38

Post by teamonkey »

grecy wrote: post #11

They neglected to mention that even modern internal combustion engines can only capture about 18%-20% of that energy.[1] [1] http://en.wikipedia.org/wiki/Internal_combustion_engine#Ener...

Oil power stations are around 33% efficient[1]. Electric drives have up to 80% efficiency[2].

Given those rough figures, even when powered by oil stations battery-powered cars can theoretically be more efficient at using oil than a car with an ICE.

[1]http://en.wikipedia.org/wiki/Oil_power_plant#Heat_into_mecha...

[2] http://en.wikipedia.org/wiki/Electric_car#Energy_efficiency

Re: How many gallons of gasoline would it take to charge an iPhone?

#39

Post by GFischer »

revelation wrote: post #15
jessriedel wrote: post #8

Earlier quoted context omitted.

All vehicles are incredibly power consuming (compared to iPods) and there are basic limits to improving this. If you want a vehicle that is large enough to hold a human and can push air out of the way at 60 mph, it's going to take a lot of energy. Driving habits, aerodynamics, and size can change this usage by a factor of order unity, but they can't do it by orders of magnitude. Thus, alternative energy sources must…

No, people need to realize that cars weighing in at 3+ tons with capacity for 5+ passengers to transport a single person to work are not viable. Because the "give us something we can hotswap for oil" attitude is obviously going nowhere.

My current car weighs 0.8 tons and has a 50 miles per gallon consumption (Renault Twingo), and the one I had before weighed 0.7 tons and could archieve up to 115 miles per gallon (according to an article) though something like 60 or 70 mpg was more normal.

http://www.aftermarketleads.com/2011/12/maruti-alto-delivers...

I suspect the problem is partly American attitude towards small cars. Japanese, Europeans and South Americans have much more efficient cars for daily commute.

Re: How many gallons of gasoline would it take to charge an iPhone?

#40

Post by Tichy »

jbooth wrote: post #5

"I bet they're going to talk about the total amount of energy in a gallon of gas, without mentioning anything about how that's translated to electrity, and how much of the energy is lost in the process" click "Yup."

Well how much energy is lost? 50%? 80%? Assuming it is 50%, then the answer would be you could charge the iPhone for 10 years instead of 20 years. Still interesting.
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