Criticism of sport utility vehicles

A 9 seater Ford Excursion SUV next to a 5 seater Toyota Camry

Sport utility vehicles (SUVs) have been criticized for a variety of environmental and safety-related reasons. They generally have poorer fuel efficiency and require more resources to manufacture than smaller vehicles, thus contributing more to climate change and environmental degradation. Their higher center of gravity significantly increases their risk of rollovers. Their larger mass increases their momentum, which results in a larger braking distance and more damage to other road users in collisions. Their higher front-end profile reduces visibility and makes them at least twice as likely to kill pedestrians they hit. ^[1] Additionally, the psychological sense of security they provide influences drivers to drive less cautiously or rely on their car for their perceived safety, rather than their own driving.^{[ citation needed ]}

Safety

SUVs are generally safer to their occupants and more dangerous to other road users than mid-size cars. A 2021 study by the University of Illinois Springfield ^[2] showed, for example, that SUVs are 8-times more likely to kill children in an accident than passenger cars, and multiple times more lethal to adult pedestrians and cyclists.

When it comes to mortality for vehicle occupants, four-door minicars have a death rate (per 100,000 registration years rather than mileage) of 82, compared with 46 for very large four-doors. ^[3] This survey reflects the effects of both vehicle design and driving behaviour. Drivers of SUVs, minivans, and large cars may drive differently from the drivers of small or mid-size cars, and this may affect the survey result.

Rollover

A high center of gravity makes a vehicle more prone to rollover accidents than lower vehicles, especially if the vehicle leaves the road, or if the driver makes a sharp turn during an emergency maneuver. Figures from the US National Highway Traffic Safety Administration show that most passenger cars have about a 10% chance of rollover if involved in a single-vehicle crash, while SUVs have between 14% and 23% (varying from a low of 14% for the all-wheel-drive (AWD) Ford Edge to a high of 23% for the front-wheel-drive (FWD) Ford Escape). Many modern SUVs are equipped with electronic stability control (ESC) to prevent rollovers on flat surfaces, but 95% of rollovers are "tripped", meaning that the vehicle strikes something low, such as a curb or shallow ditch, causing it to tip over. ^[4]

According to NHTSA data, early SUVs were at a disadvantage in single-vehicle accidents (such as when the driver falls asleep or loses control swerving around a deer), which involve 43% of fatal accidents, with more than double the chance of rolling over. This risk related closely to overall US motor vehicle fatality data, showing that SUVs and pickups generally had a higher fatality rate than cars of the same manufacturer. ^[5]

According to Consumer Reports , as of 2009, SUV rollover safety had improved to the extent that on average there were slightly fewer driver fatalities per million vehicles, due to rollovers, in SUVs as opposed to cars. ^[6] By 2011 the IIHS reported that "drivers of today's SUVs are among the least likely to die in a crash". ^[7]

Braking problems

The cars with larger and heavy size like SUV require massive amounts of braking power so the reaction of an SUV to sudden braking can be very different from that of a normal car variant which drivers are more accustomed to.^{[ citation needed ]}

Construction

Heavier-duty SUVs are typically designed with a truck-style chassis with separate body, while lighter-duty (including cross-over) models are more similar to cars, which are typically built with a unitary construction (in which the body actually forms the structure). Originally designed and built to be work vehicles using a truck chassis, SUVs were not comprehensively redesigned to be safely used as passenger vehicles. ^[8] The British television programme Fifth Gear staged a 40 mph (64 km/h) crash between a first generation (1989–98) Land Rover Discovery with a separate chassis and body, and a modern Renault Espace IV with monocoque (unit) design. The older SUV offered less protection for occupants than the modern multi-purpose vehicle with unitary construction. ^[9] In some SUV fatalities involving truck-based construction, lawsuits against the automakers "were settled quietly and confidentially, without any public scrutiny of the results—or the underlying problems with SUV design", thus hiding the danger of vehicles such as the Ford Bronco and Explorer compared to regular passenger cars. ^[10]

Risk to other road users

Ford Escort (North America) after a head-on collision with an SUV, showing the raised point of impact

Because of greater height and weight and rigid frames, it is contended by Malcolm Gladwell, writing in The New Yorker magazine, ^[11] that SUVs can affect traffic safety. This height and weight, while potentially giving an advantage to occupants of the vehicle, may pose a risk to drivers of smaller vehicles in multi-vehicle accidents, particularly side impacts. ^[12]

The initial tests of the Ford Excursion were "horrifying" for its ability to vault over the hood of a Ford Taurus. The big SUV was modified to include a type of blocker bar suggested by the French transportation ministry in 1971, a kind of under-vehicle roll bar designed to keep the large Ford Excursion from rolling over cars that were hit by it. ^[13] The problem is "impact incompatibility", where the "hard points" of the end of chassis rails of SUVs are higher than the "hard points" of cars, causing the SUV to override the engine compartment and crumple zone of the car. ^[14] There have been few regulations covering designs of SUVs to address the safety issue. ^[15] The heavy weight is a risk factor with very large passenger cars, not only with SUVs. ^[15] The typically higher SUV bumper heights and those built using stiff truck-based frames, also increases risks in crashes with passenger cars. ^[15] The Mercedes ML320 was designed with bumpers at the same height as required for passenger cars. ^[16]

In parts of Europe, effective 2006, the fitting of metal bullbars, also known as grille guards, brush guards, and push bars, to vehicles such as 4x4s and SUVs are only legal if pedestrian-safe^{[ clarification needed ]} plastic bars and grilles are used. Bullbars are often used in Australia, South Africa, and parts of the United States to protect the vehicle from being disabled should it collide with wildlife.

Safety improvements during the 2010s to the present led automobile manufacturers to make design changes to align the energy-absorbing structures of SUVs with those of cars. As a result, car occupants were only 28 percent more likely to die in collisions with SUVs than with cars between 2013 and 2016, compared with 59 percent between 2009 and 2012, according to the IIHS. ^[17]

Visibility and backover deaths

Larger vehicles can create visibility problems for other road users by obscuring their view of traffic lights, signs, and other vehicles on the road, plus the road itself. Depending on the design, drivers of some larger vehicles may themselves suffer from poor visibility to the side and the rear. Poor rearward vision has led to many "backover deaths" where vehicles have run over small children when backing out of driveways. The problem of backover deaths has become so widespread that reversing cameras are being installed on some vehicles to improve rearward vision. ^[18]

While SUVs are often perceived as having inferior rearward vision compared with regular passenger cars, this is not supported by controlled testing which found poor rearward visibility was not limited to any single vehicle class. ^[19] Australia's NRMA motoring organisation found that regular passenger cars commonly provided inferior rearward vision compared to SUVs, both because of the prevalence of reversing cameras on modern SUVs and the shape of many popular passenger cars, with their high rear window lines and boots (trunks) obstructing rearward vision. ^[20] In NRMA testing, two out of 42 SUVs (5%) and 29 out of 163 (18%) regular cars had the worst rating (>15-metre blind spot). Of the vehicles that received a perfect 0-metre blind spot rating, 11 out of 42 (26%) were SUVs and eight out of 163 (5%) were regular passenger cars. All of the "perfect score" vehicles had OEM reversing cameras. ^[21]

Wide bodies in narrow lanes

The wider bodies of larger vehicles mean they occupy a greater percentage of road lanes. This is particularly noticeable on the narrow roads sometimes found in dense urban areas or rural areas in Europe. Wider vehicles may also have difficulty fitting in some parking spaces and encroach further into traffic lanes when parked alongside the road.

Psychology

SUV safety concerns are affected by a perception among some consumers that SUVs are safer for their drivers than standard cars, and that they need not take basic precautions as if they were inside a "defensive capsule". ^[22] According to G. C. Rapaille, a psychological consultant to automakers, many consumers feel safer in SUVs simply because their ride height makes "[their passengers] higher and dominate and look down [sic]. That you can look down [on other people] is psychologically a very powerful notion." This and the height and weight of SUVs may lead to consumers' perception of safety. ^[11]

Gladwell also noted that SUV popularity is also a sign that people began to shift automobile safety focus from active to passive, to the point that in the US potential SUV buyers will give up an extra 30 ft (9.1 m) of braking distance because they believe they are helpless to avoid a tractor-trailer hit on any vehicle. ^[11] The four-wheel drive option available to SUVs reinforced the passive safety notion. To support Gladwell's argument, he mentioned that automotive engineer David Champion noted that in his previous driving experience with Range Rover, his vehicle slid across a four-lane road because he did not perceive the slipping that others had experienced. ^[11] Gladwell concluded that when a driver feels unsafe when driving a vehicle, it makes the vehicle safer. When a driver feels safe when driving, the vehicle becomes less safe. ^[11]

Stephen Popiel, a vice president of Millward Brown Goldfarb automotive market-research company, noted that for most automotive consumers, safety has to do with the notion that they are not in complete control. ^[11] Gladwell argued that many "accidents" are not outside driver's control, such as drunk driving, wearing seat belts, and the driver's age and experience.^{[ citation needed ]}

Sense of security

Study into the safety of SUVs conclusions have been mixed. ^{[23] [24]} In 2004, the National Highway Traffic Safety Administration released results of a study that indicated that drivers of SUVs were 11% more likely to die in an accident than people in cars. ^[25] These figures were not driven by vehicle inherent safety alone but indicated perceived increased security on the part of drivers. For example, US SUV drivers were found to be less likely to wear their seatbelts ^[26] and showed a tendency to drive more recklessly (most sensationally perhaps, in a 1996 finding that SUV drivers were more likely to drive drunk). ^[26]

Actual driver death rates are monitored by the IIHS and vary between models. ^[27] These statistics do show average driver death rates in the US were lower in larger vehicles from 2002 to 2005, and that there was significant overlap between vehicle categories.

US driver death rates from 2002 to 2005 in recent models (per million registered vehicles per year) ^[27]

Vehicle type	No. of models	Deaths
Small 4 door cars	14	45–191
Mid-size 4 door cars	17	14–130
Large 4 door cars	11	57–118
Mid-size luxury	8	11–54
Large luxury	11	14–85
Large mini-vans	5	36–97
Very large mini-vans	6	7–54
Small SUVs	13	44–132
Mid-size SUVs	34	13–232
Large SUVs	16	21–188
Very large SUVs	6	53–122

The IIHS report states, "Pound for pound across vehicle types, cars almost always have lower death rates than pickups or SUVs." ^{[27] [ failed verification ]} The NHTSA recorded occupant (driver or passenger) fatalities per 100 million vehicle miles traveled at 1.16 in 2004 and 1.20 in 2003 for light trucks (SUVs, pick-ups and minivans) compared to 1.18 in 2004 and 1.21 in 2003 for passenger cars (all other vehicles). ^[28]

Marketing practices

The marketing techniques used to sell SUVs have been under criticism. Advertisers and manufacturers alike have been assailed for greenwashing. Critics have cited SUV commercials that show the product being driven through a wilderness area, even though relatively few SUVs are ever driven off-road. ^{[29] [30]}

Fuel economy

The recent growth of SUVs is sometimes given as one reason why the population has begun to consume more gasoline than in previous years. ^[31] SUVs generally use more fuel than passenger vehicles or minivans with the same number of seats. ^[31] Additionally, SUVs up to 8,500 pounds GVWR are classified by the US government as light trucks, and thus are subject to the less strict light truck standard under the Corporate Average Fuel Economy (CAFE) regulations, and SUVs which exceed 8,500 pounds GVWR have been entirely exempt from CAFE standards. This provides less incentive for US manufacturers to produce more fuel-efficient models.

As a result of their off-road design SUVs may have fuel-inefficient features. High profile increases wind resistance and greater mass require heavier suspensions and larger drivetrains, which both contribute to increased vehicle weight. Some SUVs come with tires designed for off-road traction rather than low rolling resistance.

Fuel economy factors include:

• High masses (compared to the average load) causing high energy demand in transitional operation (in the cities) ${\displaystyle {P_{accel}=m_{vehicle}\cdot a\cdot v}}$ where ${\displaystyle P_{accel}\,\!}$ stands for power, ${\displaystyle m_{vehicle}\,\!}$ for the vehicle mass, ${\displaystyle {a}\,\!}$ for acceleration and ${\displaystyle {v}\,\!}$ for the vehicle velocity.
• High cross-sectional area causing very high drag losses especially when driven at high speed ${\displaystyle {P_{drag}=A_{cross}\cdot cw_{vehicle}\cdot {\frac {v_{air}^{3}\rho _{air}}{2}}}}$ where ${\displaystyle P_{drag}\,\!}$ stands for the power, ${\displaystyle {A_{cross}}\,\!}$ for the cross-sectional area of the vehicle, ${\displaystyle {\rho _{air}}\,\!}$ for the density of the air and ${\displaystyle v_{air}\,\!}$ for the relative velocity of the air (incl. wind).
• High rolling resistance due to all-terrain tires (even worse if low pressure is needed offroad) and high vehicle mass driving the rolling resistance ${\displaystyle {P_{roll}=\mu _{roll}\cdot m_{vehicle}\cdot v}}$ where ${\displaystyle \mu _{roll}\,\!}$ stands for the rolling resistance factor and ${\displaystyle m_{vehicle}\,\!}$ for the vehicle mass.

Average data for vehicle types sold in the US: ^[32]

Type	Width		Height		Curb weight		Combined fuel economy
	in	cm	in	cm	lb	kg	mpg (US)	l/100 km	mpg (imp)
SUVs	70.5	179	69.7	177	4442	2015	19.19	12.26	23.05
Minivans	75.9	193	67.2	171	4075	1848	20.36	11.55	24.45
Family sedans	70.3	179	57.3	146	3144	1426	26.94	8.731	32.35

Drag resistance (assuming the same drag coefficient which is not a safe assumption) for SUVs may be 30% higher and the acceleration force has to be 35% larger for the same acceleration, which again is not a safe assumption, than family sedans if we use the figures from the above table.

Pollution

Because SUVs tend to use more fuel (mile for mile) than cars with the same engine type, ^{[33] [34]} they generate higher volumes of pollutants (particularly carbon dioxide) into the atmosphere. This has been confirmed by LCA (Life Cycle Assessment) studies, ^[35] which quantify the environmental impacts of products such as cars, often from the time they are produced until they are recycled. One LCA study which took into account the production of greenhouse gases, carcinogens, and waste production found that exclusive cars, sports cars and SUVs were "characterized by a poor environmental performance." ^[36] Another study found that family size internal combustion vehicles still produced fewer emissions than a hybrid SUV. ^[37]

Various eco-activist groups, such as the Earth Liberation Front or Les Dégonflés have targeted SUV dealerships and privately owned SUVs due to concern over increased fuel usage. ^{[38] [39]}

In the US, light trucks and SUVs are held to a less-strict pollution control standard than passenger cars. In response to the perception that a growing share of fuel consumption and emissions are attributable to these vehicles, the Environmental Protection Agency ruled that by the model year 2009, emissions from all light trucks and passenger cars will be regulated equally. ^[40]

However, total mileage overtime must be taken into consideration when considering total emissions volume and there has been investigated in "Dust to Dust" environmental impact, considering factors other than fuel economy.^{[ citation needed ]}

The British national newspaper The Independent reported on a study carried out by CNW Marketing Research which suggested that CO₂ emissions alone do not reflect the true environmental costs of a car. The newspaper reported that: "CNW moves beyond the usual CO₂ emissions figures and uses a "dust-to-dust" calculation of a car's environmental impact, from its creation to its ultimate destruction." The newspaper also reported that the CNW research put the Jeep Wrangler above the Toyota Prius and other hybrid cars as the greenest car that could be bought in the US. However, it was noted that Toyota disputed the proportion of energy used to make a car compared with how much the vehicle uses during its life; CNW said 80% of the energy a car uses is accounted for by manufacture and 20% in use. Toyota claimed the reverse. ^{[41] [42]}

The report has raised controversy. When Oregon radio station KATU asked for comment on the CNW report, Professor John Heywood (with the Massachusetts Institute of Technology (MIT)) saw merit in the study saying, "It raises...some good questions" but "I can only guess at how they did the detailed arithmetic.... The danger is a report like this will discourage the kind of thinking we want consumers to do – should I invest in this new technology, should I help this new technology?" ^[43]

The Rocky Mountain Institute alleged that even after making assumptions that would lower the environmental impact of the Hummer H3 relative to the Prius, "the Prius still has a lower impact on the environment. This indicates that the unpublished assumptions and inputs used by CNW must continue the trend of favoring the Hummer or disfavoring the Prius. Since the researchers at Argonne Labs performed a careful survey of all recent life cycle analysis of cars, especially hybrids, our research underlines the deep divide between CNW's study and all scientifically reviewed and accepted work on the same topic." ^[44]

A report done by the Pacific Institute alleges "serious biases and flaws" in the study published by CNW, claiming that "the report's conclusions rely on faulty methods of analysis, untenable assumptions, selective use and presentation of data, and a complete lack of peer review." ^[45]

For his part, CNW's Art Spinella says environmental campaigners may be right about SUVs, but hybrids are an expensive part of the automotive picture. The vehicle at the top of his environmentally-friendly list is the Scion xB because it is easy to build, cheap to run and recycle, and carries a cost of 49 cents a mile over its lifetime. "I don't like the Hummer people using that as an example to justify the fact that they bought a Hummer," he said. "Just as it's not for Prius owners to necessarily believe that they're saving the entire globe, the environment for the entire world, that's not true either." ^[43]

In the June 2008 "From Dust to Dust" study, the Prius cost per lifetime-mile fell 23.5%, to $2.19 per lifetime mile, while the H3 cost rose 12.5%, to $2.33 per lifetime-mile. Actual results depend upon the distance driven during the vehicle's life. ^[46]

Greenhouse gas emissions

Unmodified, SUVs emit 700 megatonnes of carbon dioxide per year, which causes global warming. ^[31] Whereas SUVs can be electrified, ^[47] their (manufacturing) emissions will always be larger than smaller electric cars. ^[48] They can also be converted to run on a variety of alternative fuels, including hydrogen. ^[49] That said, the vast majority of these vehicles are not converted to use alternative fuels.

Weight and size

The weight of a passenger vehicle has a direct statistical contribution to its driver fatality rate according to Informed for LIFE, more weight being beneficial (to the occupant). ^[50]

The length and especially width of large SUVs is controversial in urban areas. In areas with limited parking spaces, large SUV drivers have been criticized for parking in stalls marked for compact cars or that are too narrow for the width of larger vehicles. Critics have stated that this causes problems such as the loss of use of the adjacent space, reduced accessibility into the entry of an adjacent vehicle, blockage of driveway space, and damage inflicted, by the door, to adjacent vehicles. ^[51] As a backlash against the alleged space consumption of SUVs, the city of Florence, has restricted access of SUVs to the center, and Paris and Vienna have debated banning them altogether. ^{[52] [53]}

Despite common perceptions, SUVs often have equivalent or less interior storage space than wagons. ^{[54] [55]} While handling worse and burning more fuel due to high centre of gravity and weight respectively. ^[56]

Activism

Siân Berry was a founder of the Alliance against Urban 4×4s, which began in Camden in 2003 and became a national campaign demanding measures to stop 4×4s (or sport utility vehicles) "taking over our cities". ^{[57] [ failed verification ]} The campaign was known for its "theatrical demonstrations" and mock parking tickets, credited to Berry (although now adapted by numerous local groups). ^{[58] [ obsolete source ]}

In Sweden, a group which called themselves "Asfaltsdjungelns indianer" (en: The Indians of the asphalt jungle), carried out actions in Stockholm, Gothenburg, Malmö and a number of smaller cities. The group, created in 2007, released the air from the tires on an estimated 300 SUVs during their first year. ^[59] Their mission was to highlight the high fuel consumption of SUVs, as they thought that SUV owners did not have the right to drive such big vehicles at the expense of others. ^{[60] [61]} The group received some attention in media, ^[62] and declared a truce in December 2007. ^[63]

Similar activist groups, most likely inspired by the Swedish group, have carried out actions in Denmark, Scotland, and Finland. ^{[64] [65]}

See also

• Automobile safety
• Environmental impact of transport
  • Air pollution
  • Environmental aspects of the electric car
  • Gas-guzzler
• Mobile source air pollution
  • Exhaust gas  – Gases emitted as a result of fuel reactions in combustion engines

References

1. Lawrence, Eric D.; Bomey, Nathan; Tanner, Kristi (1 July 2018). "Death on foot: America's love of SUVs is killing pedestrians". Detroit Free Press. Archived from the original on 14 December 2019. Retrieved 24 December 2019.
2. Edwards, M. and Leonard, D. (September 2022). "Effects of large vehicles on pedestrian and pedalcyclist injury severity". Journal of Safety Research. 82: 275–282. doi:10.1016/j.jsr.2022.06.005. PMID   36031254. S2CID   249860954.
3. "Dying in a car crash" (PDF). Status Report. 45 (5). 9 June 2011. Archived from the original (PDF) on 11 June 2014. Retrieved 19 March 2017.
4. U.S. National Highway Traffic Safety Administration (NHTSA). "Types of Rollovers". Safercar.gov. Retrieved 22 November 2015.
5. Halvorson, Bengt (26 July 2007). "Top 20 Most Dangerous Vehicles". Forbes. Retrieved 23 March 2021.
6. "Car Rollover 101". Consumer Reports. April 2014. Retrieved 22 November 2015.
7. "SUV death rates fall". Iihs.org. 9 June 2011. Retrieved 22 November 2015.
8. "SUV Safety Hazards". Public Citizen. Retrieved 12 March 2014.
9. "Smashing, great, super!". Fifth Gear. Archived from the original on 29 September 2007. Retrieved 12 March 2014.
10. Haggerty, James F. (2003). In the court of public opinion: winning your case with public relations. Wiley. p. 270. ISBN   9780471468288 . Retrieved 12 March 2014.
11. Gladwell, Malcolm (5 January 2004). "Big and Bad". The New Yorker. Archived from the original on 19 February 2016. Retrieved 30 October 2021.
12. "Side-impact crash test program". Insurance Institute for Highway Safety. Archived from the original on 30 December 2010. Retrieved 31 December 2010.
13. Bradsher, Keith (2004). High and mighty: the dangerous rise of the SUV . PublicAffairs. p.  199. ISBN   978-1-58648203-9 . Retrieved 5 September 2011. Ford Excursion the use of the blocker bar.
14. Wenzel, Tom; Ross, Marc (15 January 2003). "Are SUVs Safer than Cars? An Analysis of Risk by Vehicle Type and Model" (PDF). Transportation Research Board 82nd Annual Meeting. Archived from the original (PDF) on 9 March 2008. Retrieved 14 December 2016.
15. Polinsky, A. Mitchell; Shavell, Steven (2007). Handbook of Law and Economics – Volume 1. Elsevier. p. 605. ISBN   978-0-44451235-2 . Retrieved 14 April 2013.
16. Motavalli, Jim (2001). The Race to Build the Clean Car of the Future. Routledge. ISBN   978-1-85383785-2 . Retrieved 14 April 2013.
17. "Vehicle size and weight".
18. Hunter, Greg (27 November 2005). "SUV backover deaths: What can be done?". CNN. Retrieved 5 September 2011.
19. "Poor rear visibility common on most family cars". The Motor Report. 9 October 2009. Retrieved 5 September 2011.
20. Pleffer, Ashlee (6 December 2007). "Popular cars with rear issue". The Adelaide Advertiser. Carsguide. Retrieved 5 September 2011.
21. "Reversing Visibility Tables". NRMA. Archived from the original on 30 August 2011. Retrieved 5 September 2011.
22. Graham, Stephen (2008) [2004]. Cities, war, and terrorism. Towards an urban geopolitics. Hoboken, New Jersey: John Wiley & Sons. p.  51. ISBN   978-0-470-75302-6 . Retrieved 9 June 2016. Also quoted by Zygmunt Bauman etc.
23. "Study SUVs No Safer Than Cars". consumeraffaris.com. 3 January 2006. Archived from the original on 6 February 2012. Retrieved 5 September 2011.
24. Valdes-Dapena, Peter (20 August 2007). "Crash death rates show progress in auto safety". CNNMoney.com. Retrieved 5 September 2011.
25. Hakim, Danny (17 August 2004). "Safety Gap Grows Wider Between S.U.V.'s and Cars". The New York Times. Retrieved 5 September 2011.
26. "Overview of vehicle compatibility". National Highway Traffic Safety Administration. February 1998. Archived from the original on 17 May 2008. Retrieved 5 September 2011.
27. "Shopping for a safer car 2011" (PDF). Insurance Institute for Highway Safety. Retrieved 5 September 2011.
28. "Fatality Analysis Reporting System General Estimates System – 2005 data summary" (PDF). National Highway Traffic Safety Administration. Archived from the original (PDF) on 15 October 2011. Retrieved 5 September 2011.
29. "An Analysis of the Impact of Sport Utility Vehicles in the United States" (PDF). Retrieved 31 December 2010.
30. "2002 Vehicle Inventory and Use Survey". United States Census Bureau. December 2004.
31. "October: Growing preference for SUVs challenges emissions reductions in passenger car mark". iea.org. Retrieved 18 October 2019.
32. "Source The Auto Channel". Theautochannel.com. Retrieved 31 December 2010.
33. "Fuel Economy Guide" (PDF). EPA. Retrieved 4 February 2015.
34. "Life Cycle Assessment of Automobile/Fuel Options" (PDF). Environmental Science and Technology. Archived from the original (PDF) on 13 April 2015. Retrieved 4 February 2015.
35. Nordelöf, Anders (2014). "Environmental impacts of hybrid, plug-in hybrid, and battery electric vehicles—what can we learn from life cycle assessment?". The International Journal of Life Cycle Assessment. 19 (11): 1866–1890. doi: 10.1007/s11367-014-0788-0 .
36. "Clever: Clean Vehicle Research: LCA and Policy Measures". Belgian Science Policy. Retrieved 24 April 2020.
37. Messagie, Maarten; Boureima, Faycal-Siddikou (2014). "A Range-Based Vehicle Life Cycle Assessment Incorporating Variability in the Environmental Assessment of Different Vehicle Technologies and Fuels". Energies. 7 (3): 1467–1482. doi: 10.3390/en7031467 .
38. Coronado, Rod (2007). "The Smog Monsters vs. the ELF". Archived from the original on 25 November 2011. Retrieved 2 December 2011.
39. Tamaki, Julie; Chong, Jia-Rui; Landsberg, Mitchell (23 August 2003). "Radicals Target SUVs in Series of Southland Attacks". mindfully.org. Archived from the original on 23 November 2015. Retrieved 22 November 2015.
40. Sport Utility Vehicles, Mini-Vans, and Light Trucks: An Overview of Fuel Economy and Emissions Standards ^{[ permanent dead link ]} Congressional Research Service
41. O'Grady, Sean (7 November 2006). "Jeep Wrangler: Is this the greenest car on sale?". The Independent. Retrieved 5 September 2011.
42. CNW Marketing Research (2008). "CNW's 'Dust to Dust' Automotive Energy Report". Archived from the original on 7 May 2012. Retrieved 5 September 2011.
43. Tilkin, Dan; KATU Web Staff (17 May 2007). "Hummer vs. hybrid report raises controversy". Archived from the original on 7 November 2011. Retrieved 5 September 2011.
44. Hauenstein, Heidi; Schewel, Laura. "Checking Dust to Dust's Assumptions about the Prius and the Hummer" (PDF). Rocky Mountain Institute. Retrieved 5 September 2011.
45. Gleick, Peter H. (May 2007). "Hummer versus Prius: "Dust to Dust" Report Misleads the Media and Public with Bad Science". Pacific Institute. Retrieved 5 September 2011.
46. "Energy Cost by Model per Mile". cnwmr.com. Archived from the original on 10 June 2012. Retrieved 5 September 2011.
47. Kreisel Electric and Arnold Schwarzenegger present the world’s first electrified Hummer H1
48. Bigger is not better – how SUV's are killing the climate
49. Hydrogen cars ready to roll – for a price
50. www.informedforlife.org(PDF) https://web.archive.org/web/20070823170557/http://www.informedforlife.org/demos/FCKeditor/UserFiles/File/EQUATIONS.pdf. Archived from the original (PDF) on 23 August 2007.{{cite web}}: Missing or empty |title= (help)
51. Wurn, Diana (26 February 2006). "The incredible shrinking parking space". The Seattle Times. Archived from the original on 4 June 2011. Retrieved 5 September 2011.
52. "Grüne wollen Geländeautos aus Städten verbannen". Die Presse (in German). Vienna, Austria. 21 February 2008. Retrieved 5 September 2011.
53. Henley, Jon (10 June 2004). "4x4s into Paris won't go – if SUV ban works". The Guardian. London, UK. Retrieved 15 April 2008.
54. "SUV or station wagon – which is best? | RACV". @RACV. Retrieved 23 May 2022.
55. "Comparing wagons to SUVs". WhichCar. 29 August 2019. Retrieved 23 May 2022.
56. "5 Reasons Why SUVs Suck". Car Throttle. Retrieved 23 May 2022.
57. Siân Berry's biography, Green Party of England and Wales
58. "Alliance against Urban 4x4s Shop". Stopurban4x4s.org.uk. Retrieved 1 July 2016.
59. "Sweden: Tires Flattened on 300 SUVs by "The Indians of the Asphalt Jungle"". Infoshop News. 4 September 2007. Archived from the original on 21 February 2014. Retrieved 22 January 2012.
60. "Asfaltsdjungelns Indianer" (in Swedish). 1 February 2010. Retrieved 1 February 2010.
61. "Sweden: Tires Flattened on 300 SUVs by "The Indians of the Asphalt Jungle"". Infoshop News. 4 September 2007. Archived from the original on 27 September 2007. Retrieved 22 January 2012.
62. Simon Bynert. "Indianer i knivattack på bildäck", Aftonbladet 2007-07-26, page 32
63. "Nu tar vi indianer en paus" (in Swedish). Aftonbladet. 10 December 2007. Retrieved 1 February 2010.
64. "Asfaltjunglens indianere pifter biler i København". Politiken.dk (in Danish). 7 November 2007. Retrieved 22 November 2015.
65. "Environmental campaigners sabotage Edinburgh 4X4s with mung beans". Daily Record. 25 March 2008. Retrieved 1 February 2010.