Unit conversion


by Young Learner
Tags: conversion, unit
Young Learner
Young Learner is offline
#1
Feb9-13, 11:30 PM
P: 41
Today I came across a statistical report of world energy consumption. There was a tab named energy generated and the values were given in TWh. There was a tab named Primary energy consumed and the values were given in Mtoe. I saw that the energy generated by the world is around 20000 TWh and the Primary consumption is around 12000 Mtoe.
My questions are:
1. Why is that the Energy generated and the energy consumed are expressed in two different terms?
2. I came to know that 1Mtoe=11.63TWh, the 12000Mtoe=139560TWh. How come the consumption is so high when the generation is only 20000TWh
Phys.Org News Partner Engineering news on Phys.org
A smart prosthetic knee with in-vivo diagnoses
Old tires become material for new and improved roads
Students take clot-buster for a spin
NascentOxygen
NascentOxygen is offline
#2
Feb9-13, 11:41 PM
HW Helper
P: 4,716
Would coal and oil be classified under "Energy Generated"?
Young Learner
Young Learner is offline
#3
Feb10-13, 08:01 AM
P: 41
Does that mean 12000 Mtoe is burned to produce 20000 TWh of energy?

NascentOxygen
NascentOxygen is offline
#4
Feb10-13, 08:17 AM
HW Helper
P: 4,716

Unit conversion


Where would the fuel burnt in motor vehicles be categorized in these statistics?
Young Learner
Young Learner is offline
#5
Feb10-13, 08:38 AM
P: 41
Do you mean that they have specified the primary fuel consumed which also includes the fuel used for transportation.
That was an electrical energy statistics report
NascentOxygen
NascentOxygen is offline
#6
Feb10-13, 09:06 AM
HW Helper
P: 4,716
That is my interpretation, though based on scant information. Otherwise, the conclusion is that only 1/7 th of the fuel is converted into electric energy. Maybe they take into account the energy used in mining and transporting the coal, including that as primary consumption?
Young Learner
Young Learner is offline
#7
Feb10-13, 09:37 AM
P: 41
I was not able to upload the entire file. So, I just cropped it.
Just see whether you'd be able to come to a conclusion from the following data
Attached Files
File Type: xls stats.xls (27.0 KB, 1 views)
D H
D H is offline
#8
Feb10-13, 09:50 AM
Mentor
P: 14,473
Wikipedia indicates that world production of electrical power in 2008 was 20,261 TWh while world consumption of energy was 143,851 TWh (12,369 Mtoe). These numbers are consistent with the values specified in the opening post. A better label for that "energy production" tab would have been "electrical power production".

Does this mean that only 1/7 of the world's energy annual consumption is used for the purpose of generating electricity? No. Actually it's about 36%. Power plants aren't 100% efficient; the second law of thermodynamics gets in the way. A good chunk (61%) of the energy consumed in the production of electricity is turned into heat rather than electricity.
Young Learner
Young Learner is offline
#9
Feb10-13, 10:03 AM
P: 41
Fine, I understand. Just one clarification, Does the consumption of energy includes renewable energies such as hydro and tidal or it is just confined to coal and oil.
NascentOxygen
NascentOxygen is offline
#10
Feb10-13, 07:44 PM
HW Helper
P: 4,716
Unless the document indicates they excluded some energies, I expect it would be an estimate of energy from all sources.
Young Learner
Young Learner is offline
#11
Feb11-13, 07:20 AM
P: 41
Thank You all for the instant replies. :)
jim hardy
jim hardy is offline
#12
Feb11-13, 12:35 PM
Sci Advisor
jim hardy's Avatar
P: 3,149
Since you're interested in the subject, here's a link i enjoyed.
It's from 2007 when world use was about a cubic mile of oil per year. They try to put that in some perspective.



http://www.theoildrum.com/node/2186

It leads to to other interesting links..
Young Learner
Young Learner is offline
#13
Feb12-13, 08:10 AM
P: 41
Informative thread Jim.


Register to reply

Related Discussions
SI unit conversion HELP Introductory Physics Homework 5
Unit Conversion Introductory Physics Homework 1
Unit conversion Introductory Physics Homework 4
unit conversion Introductory Physics Homework 2
unit conversion help Introductory Physics Homework 4