The cost of improving fuel efficiency
Richard Baverstock, Founder of Mogol Inc
[email protected]
MPG
As gas prices rise, the cost of fuel becomes a greater
50
issue for consumers and businesses. The EIA notes that in
45
MY90-11
2014, the average household expenditure on gas was $2,513
40
MY12-16
35
annually1. While there is an expected drop in gas expenses for
MY17-21
30
2015, expenses are expected to rise again in 2016.
MY22-25
25
Improvements in fuel economy averaged 0.7% annually from
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1990 to 20112 (Figure 1). In model years (MY) 2012-2016, the
CAFE fleet targets increased between 1% and 4.5% annually 3.
For the period 2017-2021, the CAFE target that the NHTSA
Year
and EPA have set is an annual increase in efficiency of 3.83.9% for passenger cars. For the period 2022-2025, they are
Figure 1: Future MPG requirements are dramatically
proposing a target of 4.7% annually4. Consumers face the
increasing and will affect consumer prices
problem of increasing expenses, and auto manufacturers face
the challenge of improving the fuel economy of their vehicles.
The NHTSA and EPA estimate the average increase in cost for a new vehicle technology in 2025 could be $1,250-$1,400.
$12,000.00
$10,000.00
$8,000.00
$6,000.00
$4,000.00
$2,000.00
$0.00
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51
56
62
MPG in 2025
In 2011, the Center for Automotive Research (CAR) released a
study predicting the state of the industry in 2025 5. In this report, they
estimated the additional retail price per vehicle to achieve possible CAFE
requirements 2025. Achieving the CAFE targets will increase the retail
purchase price by about $6,770 (this corresponds to 4% green house gas
reduction or 51 MPG in Figure 2), much higher than the NHTSA and EPA
estimate. Even if this represents a 50% improvement over a consumer's
vehicle today, it will take almost 5 years for the reduced fuel expenses to
pay off6. This is just under the average new car ownership of 7 years, 7
reducing the benefit for most vehicle owners.
So while the automotive industry is on board to achieve the CAFE
standards, there appears to be little benefit to consumers. Ideally, the
industry needs to see an increase in fuel efficiency with a smaller impact on
the retail purchase price. Are there other options for improving fuel efficiency?
Figure 2: Estimated additional purchase
price for CAFE MPG targets5
1
Hutchins, Trisha and Lidderdale, Trancred “U.S. Gasoline expenditures expected to fall in 2015” April 10, 2015
http://www.eia.gov/todayinenergy/detail.cfm?id=20752
2
U.S. Department of Transportation, “Summary of Fuel Economy Performance” April 28, 2011
http://www.nhtsa.gov/staticfiles/rulemaking/pdf/cafe/2011_Summary_Report.pdf
3
NHTSA CAFE-GHG Fact Sheet
http://www.nhtsa.gov/staticfiles/rulemaking/pdf/cafe/CAFE-GHG_Fact_Sheet.pdf
4
NHTSA CAFE 2017-2025 Fact Sheet
http://www.nhtsa.gov/staticfiles/rulemaking/pdf/cafe/CAFE_2017-25_Fact_Sheet.pdf
5
Center for Automotive Research, “The U.S. Automotive Market and Industry in 2025” June 2011
http://www.cargroup.org/?module=Publications&event=View&pubID=10
6
Assuming 2014 fuel prices.
7
KBB.com “Average length of U.S. vehicle ownership hit an all-time high” February 23, 2012
http://www.kbb.com/car-news/all-the-latest/average-length-of-us-vehicle-ownership-hit-an-all_time-high/2000007854/
Copyright (c) 2015. Mogol Inc. Visit us at http://mogolinc.com
There are. In addition to improving the engineering of the vehicle, vehicle owners can choose to drive more
efficiently. Driving enthusiasts called hypermilers have been doing this for decades, with consistent results meeting or
exceeding advertised EPA efficiency. These drivers use a variety of techniques, and two of the more accessible to use are
driving with load and driving without braking.
Driving with load (DWL) refers to keeping the engine load constant.
A rudimentary way to do this is to keep a constant engine RPM, however the
engine RPM is not the best indicator. The engine vacuum pressure should be
monitored using this method. At a high level, this method results in vehicles
slowing down uphill, and speeding up downhill (Figure 3).
Driving without braking (DWB) refers to looking far enough in
advance that you minimize activating the brakes. Consider braking as a form
of energy waste; instead of the kinetic energy moving the vehicle forward,
that energy is now being released as heat in the friction of the brakes. Drivers Figure 3: DWL: Speed adjustment based
can view how often they brake and in what situations they brake as feedback
on engine load
regarding how well they are managing their vehicles momentum.
Both DWL and DWB can be difficult to perform consistently, and monitoring the engine state can be a distraction
to drivers. These methods only address the instantaneous situation, and not the conditions around the next bend in the
road.
The solution to these problems is route aware technology. Knowing the topography of the route, the changes in
speed limits and road curvature can inform the driver whether he or she is driving in the most fuel efficient way.
Intelligent cars can use this information to automatically adjust speed or engine attributes in anticipation of the road
ahead. Cars have only been able to act on what they know now; if they can predict what will happen in the future, they
can choose the most efficient way to get there.
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MPG
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Cruise Control
Glide
Figure 4: MPG comparison of a section of Highway
101 in California
Glide is Mogol's answer to the fuel efficiency challenge.
Glide takes a route to be driven, determines where the hills are
and other speed limiting attributes like road curvature and
informs the vehicle of the adjustments to make to minimize fuel
consumption. Initial testing shows a 5% improvement in some
routes, with some sections achieving almost 10% fuel efficiency
improvement (Figure 4)8. That is equivalent to 14 years of
improvements during the 1990-2011 period9! Since most new
vehicles are electronic throttle, using Glide may only require a
software with no change to manufacturing or vehicle hardware
minimizing the impact on retail purchase price.
There are many more improvements necessary to achieve the
CAFE requirements for 2025, but we can achieve a significant
portion of the required improvements with route aware technology. Route aware driving can improve fuel efficiency on
any type of vehicle, reducing engineering overhead and the vehicle purchase cost compared to engine and body
improvements.
Updated 6/16/2015 to correct retail purchase price estimate in paragraph 2 based on feedback from the CAR group.
8
Mogol Inc. “Test Run 1: Gilroy to Santa Clara” https://mogolinc.com/?page_id=78
9
Using 0.7% annual improvements over the same period.
Copyright (c) 2015. Mogol Inc. Visit us at http://mogolinc.com