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Fuel Costs

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Fuel price increases have a more pronounced impact on the fuel costs for a gas guzzler because these vehicles use more gallons per unit of distances traveled. Lets have a look at the numbers. I also explore some ideas,  technologies and smooth driver techniques that can improve fuel economy and vehicle manufacturing profitability. 

From the numbers bellow we can find that driving an efficient hybrid will save you about $1,000 per year vs a conventional vehicle. We can also see that driving an efficient diesel or hybrid will saving about $3,000 per year vs an inefficient gas guzzler.

These calculations are going to be based on the idea that a person drives 12,000 miles per year. We are going to be also using 24MPG's as the fuel economy number since this approximates the fleet average for passenger vehicles in the United States. This equates to 500 gallons.


At $2.00 per gallon yearly fuel costs are $1,000

At $3.00 per gallon yearly fuel costs are $1,500

At $4.00 per gallon yearly fuel costs are $2,000

At $5.00 per gallon yearly fuel costs are $2,500

At $6.00 per gallon yearly fuel costs are $3,000

* At $4.00 per gallon, 10 years of driving will rack up $20,000 in fuel costs.


To obtain the yearly fuel costs for an inefficient vehicle driven the same number of miles we can simply double the costs, assuming this gas hog averages 12MPG.

At $2.00 per gallon yearly fuel costs are $2,000

At $3.00 per gallon yearly fuel costs are $3.000

At $4.00 per gallon yearly fuel costs are $4,000

At $5.00 per gallon yearly fuel costs are $5,000

At $6.00 per gallon yearly fuel costs are $6,000

* At $4.00 per gallon, 10 years of driving will rack up $40,000 in fuel costs.


To obtain the yearly fuel costs for an efficient hybrid or diesel vehicle driven the same number of miles we can simply half the costs, assuming this efficient car averages 48MPG.


At $2.00 per gallon yearly fuel costs are $500

At $3.00 per gallon yearly fuel costs are $750

At $4.00 per gallon yearly fuel costs are $1,000

At $5.00 per gallon yearly fuel costs are $1,250

At $6.00 per gallon yearly fuel costs are $1,500

* At $4.00 per gallon, 10 years of driving will rack up $10,000 in fuel costs.


Clearly we can see that the 10 year term fuel cost savings of switching to an efficient vehicle from a gas guzzler can save you as much as $30,000. If we extrapolate further at look at 20 years of driving, a similar switch would salve you as much as $60,000.

Lifetime Fuel Costs (50 years of driving) 

Lets assume that over the next 50 year, gas will sell for an average of $6/gal (US 2012 equivalent)
*This assumption is highly optimistic* Lets also assume that the person only averages 10,000 miles per year. This is approximately 500,000 miles. Lets also assume that this person averages 33 miles per gallon in a reasonably efficient vehicle over this interval 50 years into the future. This person would end up burning about 15,151 gallons of gas; at $6/gal average that works out to about $91,000.

I highly doubt that gas will only sell for $6/gal 30 years from now. Not to be pessimistic, but I sincerely believe that gas will sell for more than $10/ gal within the next 25 years. If we were to wrap in all of the hidden costs associated with gasoline today, each gallon actually costs the US economy almost $15.

All of the easy oil is Gone

The fact that Canada is toiling away boiling oil out of sand provides a clear example of the fact that all the easy oil is gone. Thousands of motionless oil derricks dot the landscape of America over wells that were no longer feasible to pump: there is still oil and natural gas in those wells, but it costs more per unit of oil recovered to pump it out. The harder oil we now have to access is dirtier and harder to refine.

Developing World Demands

We also know that people in developing countries all over the world desire and are working towards the goal of car ownership. Companies like Tata Motors are looking to cash in on this growing market of limited budget vehicle consumers. Soon billions of people will be driving gas powered vehicles, and this will place increasing demand on a dwindling supply of oil, thus the price will increase. If responsible governments apply a health care tax to vehicle emissions (fuels that cause them), then we know this will also increase the retail price. If fiscally broken debt ridden government stop subsidizing gas and oil, we know the retail price will increase.

EV a Partial Solution

Electric vehicles are not the be all end all solution to our transportation problems with increasingly scarce global crude oil resources. While it is true the battery electric vehicles will become less costly and more capable over time, we simply lack the industrial capacity to displace fossil burning vehicles completely with electrically powered ones within the next 30 years.

ICE Improvments

The market for fossil fuel burning vehicles will continue to exist in 30 years because automakers will develop vehicles that are more and more efficient. Hybrid electric vehicles for example are already proving the commercial consumer viability of these fuel saving technologies in the automotive sector. There are many improvements that can be applied to existing automotive technologies.

Displacement reduction: reduced engine displacement results in lower fuel consumption. Most vehicles today are completely over-powered for the needs of the driver. Smaller engines can provide plenty of power for safe, smooth, speed limit legal driving.

Turbo-charging: this can enhance the power output of smaller motors, and it increases the overall thermodynamic efficiency of a motor. Turbo-chargers are already benefiting from advanced metal alloy and foil bearing technologies. Sequential turbo-setups remove the lag associated with turbos. Ford eco-boost engines are a great example of efficient durable OEM turbo-charging.

Start-Stop: this is a relatively inexpensive technology that stops the engine when a vehicle comes to a stop: when the driver lifts their foot off the brake pedal, the engine instantly starts back up with a faster more powerful starter motor. Adding start stop to a vehicle adds about $800 to $1400 to its unfront price. Start stop technology dramatically improves city fuel economy, where vehicles end up sitting at traffic signals idel for long periods of time.

Direct injection: this technology squirts the fuel directly into the combustion chamber at extremely high pressures, improving power output and efficiency while also reducing emissions. The high pressure direct injection results in better fuel air mixing, more complete combustion, and better energy extraction from the fuel.

Friction reduction: many of the moving parts in an engine rub, creating friction, heat and power robbing efficiency losses. Efforts to reduce friction in crank bearings, cam bearing, piston/ring/ cylinder, value guides and other components allows the engine to spin more easily, improving lubrication, cooling effectiveness, power output, responsiveness and emissions.

Mass reduction: iron and steel continue represent the dominate materials used in automobile manufacturing. Aluminum, magnesium, plastics and composites offer the same kinds of safety and strength as steel, at a fraction of the weight. The use of weight reducing components can shave as much as a 1000lbs off of an mid sized passenger vehicle. This kind of weight reduction improves performance while also improving fuel economy. A 1000lb weight reduction can improve the fuel economy of an existing 3200lb car by as much as %30.

LRR tires: these tires waste less energy as heat. They end up boosting your fuel economy by 1to 4%, resulting in fuel costs savings that actually pay for the tires.

Aerodynamic improvements: one of the primary problems with current boxy vehicle desires exits in the amount of energy it takes to push these boxy shapes through the air. Think of what a boat hull or air-craft is shaped like and compare that to the relatively rectangular boxy shapes of passenger vehicles. Fuel economy improvements of up to %40 can be achieved at highway speeds in a vehicle with substantially less turbulent aerodynamics. Vehicle designers are challenged in making vehicles more aerodynamically efficient while also meeting consumer aesthetic desires. Remember that vehicle purchases are more often then not emotionally driven. That said, increasing numbers of people are willing to tolerate aerodynamically efficient soybean shaped cars like the Prius :)

Brake energy recovery systems: these systems take the energy that is normally wasted scrapping a pad against a disc rotor or brake drum, and capture this energy to store it for re-use during acceleration. In hybrid vehicles this is known as "regenerative braking", when the motor generators are run backwards to charge the battery when you press on the brake pedal to slow the car down. Brake energy recovery can be accomplished with gas compression, fluid compression, mechanical flywheel storage or electrical storage systems. Electrical and hydraulic hybrids are the dominate systems that utilize brake energy recovery in the commercial/ consumer transportation sector. Mechanical flywheels known as KERS (kinetic energy recovery systems) have found a niche market in racing vehicles, although this technology may be evolved and adapted for widespread commercial applications.

Electric system improvements: electric power steering, electric air conditioning, high efficiency lights and auxiliary motors, high efficiency speakers and stereo amplifiers. The electrical systems in a car be made lighter and more efficient. Auxiliary system loads can use a lot of energy. Improvements in these systems can reduce overall energy consumption, improving fuel economy.

Exhaust energy recovery systems: can be used for rapid preheating of the engine, which reducing fuel consumption and emissions. Faster warmup time is associated with enhanced engine life and improved fuel economy. Turbo-charing is a form of exhaust heat recovery. Turbo-electric systems can also be used in hybrid vehicles to provide additional electric energy for the energy storage system: increasing the amount of time the hybrid can operate in electric or electrically assisted modes, further improving their fuel economy.

Hybridization and Plug In Hybridization: Toyota, the market leader of hybrid vehicle sales has already sold over 4 million hybrid electric vehicles worldwide. Every major auto-maker has invested in the development of hybrid electric vehicle technologies. Its important to note that hybrid vehicles and their engines can benefit from all of the applied improvements listed above. Vehicles like the Toyota Prius and Chevy volt can greatly benefit from improved aerodynamics and weight reduction for example. Plug in hybrids offer many of the benefits of Electric only driving, without the major penalties of restricted range and excessively long recharging times. Plug in hybrids are also less expensive than pure EV's with a similar range. The Plug in Prius for $32K and Chevy Volt for $40K are great examples.

Rare Earth Metal Reduction: electric motors that use magnets currently rely on rare earth metals in their construction. These rare metals are produced mainly in China, where the government has placed exportation limits, giving rise to substantial price increases. These rare metals are used in advanced batteries and semiconductors. Switched reluctance motors are a technology that does not require these rare metal magnets. In a hybrid or electric vehicle, a transition to magnet free electric motor technology is an essential part of future power-train development. Other metal allow improvements can be used to reduce the costs of wiring, for example aluminum copper alloys, and since complex electric system are now pervasively used in modern vehicles, any minor cost reduction in the wiring translates to lower costs of production.

Cost Efficient Technologies: streamlining the use of a window motors, window motor switchs, door lock drive motors and mechanisms, lock beepers, lighting systems and other sub-systems and devices in order to increase volume and reduce component costs: this will help to improve profitability of vehicle production while also stabilizing retail prices for consumers. There is absolutely no need to completely re-invent many parts. The automakers need to focus on developing "one really good" blower motor, window drive motor, switch, bulb assembly, ect: and then use the really goon one across all of their models. The focus should be on iteratively enhancing the performance, efficiency and reliability of these components across the companies portfolio. The auto industry even has the capacity to collaboratively develop sub-components that can be shared across different makes and models of vehicles. Think of the way that battery makers switched to a few standard size formats (AA, AAA, C, D, 9V). Standards help to reduce repair costs as well. This can improve profitability for an auto mechanic and parts retail store, while also reducing costs to consumers. Everyone stands to benefit from the development of shared parts standards. Putting the same size oil drain plug on all vehicles for example..... there are lots of simple examples where the automakers, mechanics and consumers can benefit from collaborative parts development, part standardization, and technology sharing. Yes SAE I am looking at you ~


Production Emissions Reductions: fuel economy and tail pipe emissions do not tell the whole story behind a vehicles impact on the environment. Improved manufacturing can dramatically reduce material and energy waste associated with a vehicles production. Many Subaru's for example are rated as Partial Zero Emissions vehicles despite their relatively low fuel economy performance because Subaru invested in substantial green house gas reduction efforts on its manufacturing operations: these actions and the credits they produce are then applied to the net lifetime carbon footprints of each vehicle, resulting in an overal net reduction similar to that achieve in a hybrid vehicle. Unfortunately, the owner of the Subaru does not see this carbon reduction directly as their fuel costs remain high.

"Smooth" Driver Training: Anyone in any vehicle can boost their fuel economy by driving less aggressively. Smooth steady safe driving places less costly mechanical wear on a vehicle, while also reducing fuel costs and emissions. This smooth safe driving is also associated with fewer accidents and enhanced passenger safety. Right now, aggressive, reckless, negligent, distract and or intoxicated drivers take the lives of tens of thousands of innocent people every year. Pedestrians and bicycle riders are frequently struck and killed or paralyzed by negligent drivers who "didn't see the person, bicycle, or traffic signal". Driving smooth, gentle and safe driving is better for your wallet, better for the environment, and better for the health and safety of everyone else.

Gentle on the gas pedal and gentle on the brake pedal. The driver has the biggest effect on fuel economy. Aggressive drivers not only wear out their vehicles faster, they also observe fuel economies far lower than the EPA rating of their vehicles. Irrational dangerous aggressive driving burns through tires, brakes, and fuel much faster than intelligent safe conservative driving. I am not talking about driving super pokey slow to the point of irritating other drivers, I am talking about calm smooth steady careful driving that requires thoughtful restraint and control.

Many newer cars will give you some form of "eco" feedback to let you know if you are driving "fuel efficiently". The trick here is to drive carefully and smoothly. For example not racing to a stop light, or red tail lights, think smooth and steady. Imagine you had fragile cargo (you do, you or you and your passengers), and you are trying to keep the philosophical egg balanced on the dash board. Driving smooth and steady, especially on the open road, will result in better than EPA fuel economy results.

My father and I took a trip in our 1992 Subaru Legacy sedan from Seattle to Olympia recently (about 70miles one way). Normally, if I drove like the average person does on I5, the Subaru returns about 28MPG on the highway (24 in mixed city driving). By going 50-55MPH the whole way, we got 38MPG's. This car is over 20 years old and has north of 160,000 miles: thats 8MPG better than the 30MPH highway it was rated at when it was new. No special tricks, just smooth and steady 50-55 MPH in the right lane. It turns out that aerodynamic (wind pushing) losses are much greater at speeds over 50MPH. Most vehicles, including our subaru have an aerodynamic coefficient (CD) of 0.31 or higher. Keeping the high way speeds lower (around 50MPH) allows these relatively boxy vehicles to cut through the air without a lot of losses. Driving the same slower smoother way from Seattle to Olympia and back in my Prius returns close to 60MPG's.

Hypermiling is a term that describes "Driving techniques that allow you to achieve better than the EPA fuel economy ratings." Extreme hypermiling techniques can be dangerous (like drafting closes in the wind box behind a large semi-truck), but most of these fuel saving techniques are simple and come down to driving very calmly and intelligently. If you want to make a game out of beating the EPA rating for you car, then welcome to the Fossil Fuel conserving world of hypermiling :)


Hypermiling Techniques 

"Pulse and Glide" : this is really only possible in Hybrids and Manual Transmission cars. The idea here is to allow the car to coast as much as possible, where the Pulse is the "engine powered part" and the Glide is the "Kinetic Momentum" "coasting" part. In an automatic transmission car, the equivalent is gently accelerating to the speed limit and then driving smoothly to keep you car at that speed (slowing down and speeding up again wastes fuel, brake pads and tire tread). 

"Gentle Foot" Gentle acceleration, low RPM shift points, ect. If you are driving a manual, this means keeping the car in higher gears to take advantage of the longer gearing. If you are driving an automatic, the engine will automatically shift to a higher gear sooner if you are gentle on the throttle. 

"Early Soft-Brake ", this is where you preemptively anticipate an upcoming stop several hundred feet in advance, and gently apply the breaks softly so as to keep up your momentum by the time the light changes so you dont have to stop. This can be then combined carefully with "catch the light", a very similar idea which requires light signal analysis/ prediction and early soft brake.

"Catch the light" is where you slow down so as to still be moving when the signal allows you to go again, and that includes taking into account how many vehicles are stopped at the signal in front of yours and estimating how fast they will accelerate. If you can see the light from the previous light, this includes avoiding speeding up the maximum speed: your goal is to catch all the green lights so you never have to stop the car completely, only gently speeding up and slowing down. In a manual transmission, this will result in a lot less shifting :), in any other vehicle it will bost you city fuel economy by %20 or more.

"Wave Cancel" in heavy traffic you slow down to 2, 3, 4, 5, 6, 7, 8 or whatever really low MPH speed needed to avoid stopping and starting constantly: this can save your leg/ clutch in a manual vehicle: if you are careful to observe this, you will note that large trucks do that as a general practice. This is known as wave canceling in physics. Stop and go traffic formations can be viewed as "Standing Waves", where wave cancel seeks to cancer out the dips and crests (stops and starts). This requires leaving a buffer zone infront of your car, and do not be surprised if a bunch of impatient rude morons cut you off because they see an opening in front of your car (your buffer zone), when that happens, slow down even more to create another buffer and then enjoy watching the tool that cut you off mashing their pedal back and forth ( as you coast along nicely wave canceling behind them) : don't get smug about it either, your not that special! Everyone is Equal in Gods eyes... with wave canceling you do get to enjoy a car that costs less to operate because wave canceling reduces wear and tear on your car and also boosts your fuel economy. In stop and go traffic, this can result in a %20 or better fuel economy increase.

"Corning dubbing" where you deceleration ahead of a known corner such that you reach the safe cornering speed by the time you get to the corner without touching your brakes or the gas pedal. Ripping around corners to conserve your forward momentum will put more stress in your cars tires, and is totally inappropriate in wet or snowy conditions. The idea hear is to keep your speed so less gas is required to speed back up again when you clear the corner. Most cars can clear a tight corner with careful driving at 15MPH. Don't exceded your comfort level, or you will likely end up kissing the curb with one of your rims, knocking your wheel alignment out of balance.

"Hill Speed Jockying" where you gently accelerate to above the speed limit on when approaching a hill, and then back of the gas pedal a little to allow you vehicle to decelerate down to slightly below the speed limit as you crest the hill, then you can use gravity not the gas pedal to allow the car to speed back up on the way down, and on the way down, allowing your car to go slightly above the posted speed will slightly boost your fuel economy (use careful judgement here).










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