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<onlyinclude>'''Fuel economy''' is a measurement of [[secondary fuel|fuel]] use (often, but not always, [[gasoline]]) for [[motor vehicle]]s.</onlyinclude> A similar concept is [[fuel efficiency]], as it relates to [[thermal efficiency]], click [[fuel efficiency|here]]. To learn about the difference between fuel efficiency and fuel economy, click [[fuel efficiency vs fuel economy|here]].
<onlyinclude>'''Fuel economy''' is a measurement of [[secondary fuel|fuel]] use. This measures how far a car can go using a set amount of fuel. Its units are [[miles per gallon]]—or for an electric vehicle, [[miles per  gallon gasoline equivalent]] (MPGe).</onlyinclude> Sometimes, the term [[fuel efficiency]] is used. Its important to note that this is a colloquial term which is used in place of fuel economy.<ref>This is information obtained from speaking to John Heywood, Professor of Mechanical Engineering at MIT; Sun Jae Professor, Emeritus</ref> Moreover, fuel economy may be confused with [[fuel consumption]], however, these have different meanings—to learn more click [[fuel consumption vs fuel economy|here]].


==Average economy of all vehicles on the road in USA==
==How to improve fuel economy==
Average fuel economy of all vehicles on the road in the USA,<ref name=book1>http://www.rita.dot.gov/bts/sites/rita.dot.gov.bts/files/publications/national_transportation_statistics/html/table_04_23.html</ref> listed in [[gallon]]s per 100 [[mile]]s.
:''[[improving fuel economy|main article]]''
It may not seem like it, but acceleration and speed during driving have a tremendous effect on fuel efficiency. Things like slowing down a little, not accelerating so rapidly substantially improve fuel efficiency. Also properly inflating tires to their proper [[pressure]] makes a big difference.
 
==Savings based on fuel economy==
:''[[fuel economy savings|main article]]''
This is a table of fuel and [[carbon dioxide]] savings based on the fuel efficiency of the vehicle. Keep in mind that the make of the vehicle is not important here. [[Gasoline]] consumed is strictly how much gasoline is consumed, regardless of the type of car or truck it is.
{| class="wikitable"
{| class="wikitable"
|-
|-
! Vehicle type !! 1990 !! 1995 !! 2000 !! 2005 !! 2010 !! Improvement
! MPG (US) !! Example !!km/L !! L/year !! kg CO<sub>2</sub> produced !! Savings from 24mpg ($1.20/L) !! 5 year savings !! 10 year savings
|-
| 18 || Jeep Wrangler ||7.58 || 2234 || 5,343 || Costs an extra $668.40 || -$3342 || -$6,684
|-
| 24 || Toyota Camry V6 ||10.1 || 1677 || 4,011 || 0 || 0 || 0
|-
|-
| Car || 4.92 || 4.74 || 4.57 || 4.52 || 4.26 || 15.7%
| 30 || Mini Cooper Clubman ||12.63 || 1341 || 3,207 || $403 || $2,015 || $4,030
|-
|-
| Truck || 6.21 || 5.78 || 5.75 || 5.65 || 5.81 || 6.8%
| 38 || Fiesta 3-cyl ||16 || 1059 || 2,533 || $741 || $3705 || $7,410
|-
| 45 || VW Golf TDI ||18.95 || 894 || 2,403* || $939.60 || $4,698 || $9,396
|-
| 60 || Kia Rio 1.1 CDRi ||25.26 || 671 || 1,603 || $1,208.40 || $6,042 || $12,084
|-
| 73.5 || VW Golf TDI Bluemotion <ref>http://green.autoblog.com/2013/06/26/new-vw-golf-tdi-bluemotion-is-most-fuel-efficient-ever-with-73/</ref> || 30.94 || 547.6 || 1,309 || $1,355.28 || $6,776.40 || $13,552.80
|-
| 114** || Nissan Leaf || 48 || --- || 844 || $1,588 || $7,944 || $15,888
|}
|}
<nowiki>*</nowiki>[[Diesel]] emits 2.7 kg CO<sub>2</sub> per liter<ref>http://www.eia.gov/tools/faqs/faq.cfm?id=307&t=11</ref>


This is a chart of average fuel economy of all cars on the road in the United States, by year. Comparing these results to the fuel economy averages for new vehicles, listed below, there is a large discrepancy. There are three reasons for this. Most importantly, new cars achieve better fuel economy than older cars, and the older cars on the road bring down the average efficiency.
<nowiki>**</nowiki>[[Miles per gallon gasoline equivalent|MPGe]]


Secondly, EPA regulations (CAFE - Corporate Average Fuel Economy standards) dictate that the average fuel efficiency across a manufacturer's line of vehicles must be above a certain number - from 1985 to 2010 this number was 27.5 [[MPG]].<ref name=book1>http://www.rita.dot.gov/bts/sites/rita.dot.gov.bts/files/publications/national_transportation_statistics/html/table_04_23.html</ref> Unfortunately, while CAFE standards may seem like a simple number, the reality is much more complex. CAFE standards are based off of vehicle footprint (area between the wheels), meaning that a vehicle with a smaller footprint will have to achieve higher fuel efficiency than one with a larger footprint (ie. a compact hatchback vs. a truck). As if this was not confusing enough, CAFE standards also only apply to vehicles under a Gross Volume Weight Rating (GWVR) of 8500 [[pound]]s. This means that companies like Ford and Dodge, who make three-quarter ton vehicles like the F-250 and the Ram 2500 have an incentive to make those vehicles heavier, so that they don't have to conform to CAFE standards. This means that the real-world efficiency of car company's new cars is actually less than the stated fuel efficiency.
==Fuel economy conversions==
[[File:energuide label.jpg|400px|thumb|right|Figure 1.This is an example of the official label for a gasoline vehicle which outlines the fuel economy and consumption along with other information.]]


Finally, the average taken is called a "harmonic average," which means that it partially takes number of units sold into account, but not at a 1:1 ratio.<ref name=book1/> This means that manufacturers can use all their models to balance out fuel efficiency, and that the companies can disproportionately increase their average with small cars that don't sell many units, and electric cars, which throw a wrench in the averages. This leads to a decrease in the real-world fuel efficiency of the average car.


==Average fuel economy of new cars in USA==
The metric system of discussing fuel economy is the same as the imperial system—the world has adopted the units of [[miles per gallon]] (see Figure 1). However, [[fuel consumption]] (a term sometimes confused with fuel economy) is measured in [[liters per hundred kilometers]] in the metric system.
Average fuel economy of new cars in the USA.<ref name=book1>http://www.rita.dot.gov/bts/sites/rita.dot.gov.bts/files/publications/national_transportation_statistics/html/table_04_23.html</ref> Values are listen in gallons of fuel per 100 miles driven. This allows for direct comparison of improvement. A unit volume of fuel per a distance is known as a measurement of fuel consumption.
The unit converter below can help explore this difference between fuel consumption and fuel economy:
{| class="wikitable"
<html><br /> <iframe src="https://energyeducation.ca/simulations/converter/converter.php?defaultMeasure=Fuel Efficiency&defaultFrom=litre/100km&defaultTo=mile per gallon (US)" scrolling="no" width="850" height="200"> </iframe><br /> </html>
|-
! Vehicle type !! 1990 !! 1995 !! 2000 !! 2005 !! 2010 !! 2011 !! 2012 !! Improvement
|-
| Domestic car || 3.72 || 3.61 || 3.48 || 3.28 || 3.02 || 3.07 || 2.91 || 21.8%
|-
| Imported car || 3.34 || 3.30 || 3.53 || 3.34 || 2.84 || 2.83 || 2.67 || 20.2%
|-
| Truck/SUV || 4.80 || 4.88 || 4.69 || 4.52 || 3.97 || 4.08 || 4.00 || 16.8%
|}
This is a chart of average fuel economy for new cars and trucks being sold in the USA. It highlights a few trends. The first being that imported cars tend to get significantly improved gas mileage over domestic cars, and that gas mileage improvements have been fairly stagnant, showing around 21% improvement average for cars, and only 16.8% improvement for trucks, over the course of the past 22 years.


It is an important thing to note, that the [[engine]]s in trucks and SUVs are generally just as efficient as the engines in cars. The main difference in their fuel economy comes from the fact that trucks and SUVs are [[mass|significantly heavier]] than cars, as well as far less [[drag|aerodynamic]].<ref>https://engineering.mit.edu/ask/what%E2%80%99s-difference-between-fuel-efficiency-and-fuel-economy</ref> Trucks are very necessary for contractors, or in construction, but buying a truck as a commuting vehicle because of an occasional need to tow a boat will end up costing a lot of money in fuel, and increase an individual's [[carbon dioxide|CO<sub>2</sub>]] footprint significantly.
==For Further Reading==
*[[Fuel consumption]]
*[[Fuel consumption vs fuel economy]]
*[[Fuel economy savings]]
*[[Transportation]]
*[[Alternative fuel vehicle]]
*Or explore a [[Special:Random|random page]]


==References==
==References==
{{reflist}}
{{reflist}}
[[Category:Uploaded]]
[[Category:Uploaded]]

Revision as of 22:09, 13 August 2018

Fuel economy is a measurement of fuel use. This measures how far a car can go using a set amount of fuel. Its units are miles per gallon—or for an electric vehicle, miles per gallon gasoline equivalent (MPGe). Sometimes, the term fuel efficiency is used. Its important to note that this is a colloquial term which is used in place of fuel economy.[1] Moreover, fuel economy may be confused with fuel consumption, however, these have different meanings—to learn more click here.

How to improve fuel economy

main article

It may not seem like it, but acceleration and speed during driving have a tremendous effect on fuel efficiency. Things like slowing down a little, not accelerating so rapidly substantially improve fuel efficiency. Also properly inflating tires to their proper pressure makes a big difference.

Savings based on fuel economy

main article

This is a table of fuel and carbon dioxide savings based on the fuel efficiency of the vehicle. Keep in mind that the make of the vehicle is not important here. Gasoline consumed is strictly how much gasoline is consumed, regardless of the type of car or truck it is.

MPG (US) Example km/L L/year kg CO2 produced Savings from 24mpg ($1.20/L) 5 year savings 10 year savings
18 Jeep Wrangler 7.58 2234 5,343 Costs an extra $668.40 -$3342 -$6,684
24 Toyota Camry V6 10.1 1677 4,011 0 0 0
30 Mini Cooper Clubman 12.63 1341 3,207 $403 $2,015 $4,030
38 Fiesta 3-cyl 16 1059 2,533 $741 $3705 $7,410
45 VW Golf TDI 18.95 894 2,403* $939.60 $4,698 $9,396
60 Kia Rio 1.1 CDRi 25.26 671 1,603 $1,208.40 $6,042 $12,084
73.5 VW Golf TDI Bluemotion [2] 30.94 547.6 1,309 $1,355.28 $6,776.40 $13,552.80
114** Nissan Leaf 48 --- 844 $1,588 $7,944 $15,888

*Diesel emits 2.7 kg CO2 per liter[3]

**MPGe

Fuel economy conversions

Figure 1.This is an example of the official label for a gasoline vehicle which outlines the fuel economy and consumption along with other information.


The metric system of discussing fuel economy is the same as the imperial system—the world has adopted the units of miles per gallon (see Figure 1). However, fuel consumption (a term sometimes confused with fuel economy) is measured in liters per hundred kilometers in the metric system. The unit converter below can help explore this difference between fuel consumption and fuel economy:

For Further Reading

References

  1. ↑ This is information obtained from speaking to John Heywood, Professor of Mechanical Engineering at MIT; Sun Jae Professor, Emeritus
  2. ↑ http://green.autoblog.com/2013/06/26/new-vw-golf-tdi-bluemotion-is-most-fuel-efficient-ever-with-73/
  3. ↑ http://www.eia.gov/tools/faqs/faq.cfm?id=307&t=11
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