Talk:Miles per gallon of gasoline equivalent

message: In respect to electric energy, the previous material is technically flawed.  It is a serious flaw because it falsely shows a degree of superiority of an electric car which is excessive.  Electric cars have considerable merit without false claims confusing the issue.  While a MPGe concept could be useful for comparing  the merits of different fuels used to produce heat, the concept of comparing fuels that produce heat energy with electric energy is not valid and asserts an equivalence that is false.  The second law of thermodynamics stands in the way of such a comparison, as clearly explained in Sears, Principles of Physics Series, Mechanics, Heat and Sound, Addison-Wesley Press, 1950. Sears discusses the heat engine that is required to convert heat into mechanical energy.  Electrical energy is then produced using that mechanical energy.  On this basis it can be seen that there can be a serious flaw in the comparison process.  
To avoid making a fraudulent comparison, it is possible to define an average heat engine by which the electricity was produced, and then compare the heat supplied to such an average heat engine with the heat supplied by burning the other listed fuels in whatever system is being considered. Vehicle miles per BTU can then be meaningfully compared and this can be translated into terms of MPGe to achieve a comparison in familiar terms. --70.231.132.254 14:59, 14 December 2007
: Your argument is flawed in that electricity production is not solely produced via combustion of fuels.  It can also be derived from nuclear, hydro, wind, or solar sources.  I think we would need a new term to represent Well to Wheel energy resource consumption and CO2 emissions to fully account for what you are trying to assert.  --D0li0 (talk) 00:25, 14 January 2008 (UTC)
replies: text: It seems 114,100 BTU is at the low end of the LHV scale for gasoline.  It goes up to 116,090 in google searches.  A value of 115,000 BTU seems common, a good compromise and consistent with the GGE page.  It's also used by the ORNL - http://bioenergy.ornl.gov/papers/misc/energy_conv.html   Ephdot (talk) 15:53, 23 March 2008 (UTC)
thread_title:  Well to Wheel MPGe 

message: It would be rather handy to have an MPGe conversion template, or to integrate mileage units such as Template:Mpg, Template:Mpg (Imperial), Template:L100km, and Template:Auto mpg into the universal Template:Convert.  It should accept the base unit for the vehicles native fuel type such as , miles per kWh for electric, or MPG of Diesel fuel. --D0li0 (talk) 12:57, 14 January 2008 (UTC)
thread_title:  MPGe Conversion Template 

message: "There is a common argument that electricity could also come from processes that do not burn fossil fuels.  It is reasonable to plan a future where wind and solar sources will be there to carry the added load of electric vehicles, but for the present infrastructure without large capital infusions the response to an added electric load will be filled from the existing national generating capacity. So the efficiency of this network of heat engines is relevant to the efficiency comparison."
: Hearsay. Ephdot (talk) 20:59, 22 March 2008 (UTC)
replies: text: Coal is used as a measure because it's just about the worst polluter and equates to current efficiencies of automobiles - about 33%.  Nothing supports this argument.  The cost of coal is only part of the equation.  Very dependent on area.  Québec gets all it's power from hydro dams. I think the case was already made.  Ephdot (talk) 20:59, 22 March 2008 (UTC)

text: replaced by a more verifiable example. Ephdot (talk) 21:00, 22 March 2008 (UTC)
thread_title:  moved comments 

message: This page is very, very confusing.  Unnecessarily so.
I would start this page by mentioning MPGge and then contrast that to whatever you are trying to document here.  Lots of people take MPGe to be MPGge.
The thing people are looking for 1 gallon of gasoline = 115,000 BTU.   115,000 BTU/3412 BTU/KWHr = 33.7 KWHrs.   Thus a car that uses 150 watt hours per mile has an MPGge of 33.7 KWHr/ gallon / 150 watt hrs per mile = 224 MPGge.
: Put simply, this conversion is impossible.  Conversion of heat energy completely to power is not possible.  The article tries to explain this. Ephdot (talk) 16:31, 20 May 2008 (UTC)
replies: text: But it IS complicated.  Simple conversions are simply wrong.  Ephdot (talk) 16:31, 20 May 2008 (UTC)
thread_title:  A simple concept made very confusing. 

message: The table has a number of values that are clearly wrong.  For example the equivalents in several rows do not vary with column heading. Gas is natural gas? What is the 14kwh?  Natural gas is around 11kWh?  There needs to be a column for reference information. 96.252.103.113 (talk) 03:10, 19 May 2009 (UTC)
thread_title:  The conversion table is a mess and should either be deleted or significantly improved 

message: The fancy sort table allows you to shuffle efficiency depending on whether your electricity comes from coal, gas or some perfect fuel.  Note that most of the entries don't use electricity so it doesn't really apply.  I've coloured the electric ones in blue and labelled them A, B & C. All the others I've labelled 1, 2, 3 ... The first three I've coloured yellow.  Note that only the coloured part of the table changes with respect to whether your electricity source is coal, gas or the theoretical maximium.  This would be better as two tables.  We be able to get rid of a lot of meaningless clutter (the gas and coal entries for modes which don't generate electricity from either).

Transportation                                                                                                      	11 kWh (Coal)	14 kWh (Gas)	30 kWh
                                                                                                                    	             	            	
Bicycling                                                                                                           	             	            	
Electric bicycle (single test)Test: 250 W electric bicycle efficiency = 1512 MPG equivalent (5.41 miles) on 0.12 kWh	             	            	
Walking                                                                                                             	             	            	
TGV train 64.80 MJ/km × 436 passengers                                                                              	             	            	
Neighborhood electric vehicle169 Wh/mi × 1.3 passengers                                                             	             	            	
Rail (Passenger - avg UK)                                                                                           	             	            	
Toyota Prius (hybrid vehicle) (US data)Compare Old and New EPA MPG Estimates 46 × 1.3=60                            	             	            	
Toyota Prius (hybrid vehicle (UK data)()(occupancy 1.58)                                                            	             	            	
Motorcycles (avg US)[http://cta.ornl.gov/data/tedb26/Edition26_Chapter02.pdf
Transportation Energy Data Book, 2007] 	             	            	
Rail (Commuter - avg US)                                                                                            	             	            	
Rail (Intercity Amtrak - avg US)                                                                                    	             	            	
Rail (Transit Light & Heavy - avg US)                                                                               	             	            	
Automobile (avg US)US fleet mileage averages 23 mpg, occupancy avg is 1.57                                          	             	            	
Air (avg US)                                                                                                        	             	            	
Buses (avg US)                                                                                                      	             	            	
Hydrogen automobile27 MPGe × 60% × 1.57 passengers                                                                  	             	            	
Steamship (estimate)                                                                                                	             	            	
Helicopter (estimate)                                                                                               	             	            	
                                                                                                                    	             	            	

;Notes
JIMp talk·cont 22:22, 22 August 2009 (UTC)
thread_title:  Sort table