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Cars Hog Energy: Drive Less = Lower Carbon Footprint

A lot of media attention has been given to the 40MPG claims of the major automakers latest 4cyl compact cars; mostly because it can be difficult for normal people to achieve the "optimistic" EPA sticker fuel economy ratings.
No matter how you roll, in a Nissan Leaf, Tesla Model S, Toyota Prius, Honda Accord, Chevy Cruze, or whatever, heavy 3000ish lbs steel vehicles take a lot of energy to move around. If you don't believe me go ahead and tie a rope to your cars frame, put it in neutral and try to pull it around.

Many arm-chair environmentalists promote eco-friendly energy efficient vehicles as a way to reduce ones carbon footprint on Earths thin atmosphere. Sadly, the reality is that all vehicles, especially heavy ones made of iron and steel, are energy hogs no matter if they are powered by batteries, hybrid systems, or a regular internal combustion engine/ transmission combo.


If you drive a normal sedan 15,000 miles per year your carbon vehicle carbon footprint will be similar to a SUV driver that only goes 5,000 miles per year. Heavier vehicles are obviously more energy intensive to operate, but the real determinate of a vehicles annual energy use and corresponding operating carbon footprint is how often the vehicle is driven and over what specific distances per trip. Driving any vehicle less often will reduce its carbon footprint, while driving any vehicle more will increase its energy use and carbon footprint.

The 8th National Dump the Pump day is coming up on June 20th 2013. Thinking about this event is what inspired this posting.

The key to reducing your vehicles carbon footprint is to drive less.

You can also reduce your transportation carbon footprint by choosing to move closer to where you work. This may often involve a trade off of home size as homes near popular areas tend to cost more than homes distant from large cities.

Commuting over large distances is for many people the most carbon intensive thing they choose to do. I can hear the complaints coming from people that live near me in "expensive" central Puget Sound Washington. Real-estate near or around "Lake Washington" is very expensive because so many people love this area and are willing to pay a lot for homes here. So people looking for a 4 bedroom 3 bath home with a two car garage who cannot afford half a million or more often choose to look for homes outside of central puget sound, in the surrounding less expensive suburban and urban areas where they are then forced to endure expensive time wasting and dangerous commutes in order to access their daily jobs and errands.

Sadly when someone adds 10 miles one way to their commute in a medium high density area like Bellevue Wa, they can be adding as much as 30 minutes each way of extra commuting. In addition to squandering more of an individuals intrinsically limited time every work day, the cost of commuting larger distances can take away thousands of dollars from an individuals budget every year. That is with gas at close to $4 usd per gallon or around $0.77 usd per liter. If gas prices go up beyond $5usd per gallon it will make long distance commutes fiscally impractical for many people that live in suburban and rural areas.

I remember the local park and ride exploding in popularity when gas prices went from $2/gal to $3/gal in a matter of months. All of a sudden people were willing to take the bus. Hmmmm

I expect that future Gas Prices will Increase

With billions of humans rising out of poverty and into the materially rich depression inducing middle class, the market for gas burning vehicles is going to get much larger.  The market for gas powered vehicles worldwide is already growing at a wild rate. Asia has become a huge market for the automakers, while India's auto market grows, and so does the auto market for vehicles in South America and many countries in Africa.

No one is manufacturing crude oil at the scale needed to significantly augment supplies for a market this large, let alone a rapidly growing market this size. In basic economic terms this means oil supply is going to be more constrained while demands for oil increase: which would inexorably translate into higher costs. Think about that. You don't anyone needs a decree in economics to understand why gas prices are going to increase.

Some will claim that the GTL process will solve the problem with oil supply, as it allows companies to convert coal and natural gas into diesel. Others claim that the Mobil process that coverts natural gas to methanol and then gasoline will be able to solve supply problems. Synthetic gasoline and diesel made from natural gas and coal might become a large part of the supply but only if consumers are willing to pay more than $5use per gallon.

Hybrid, Plug-in Hybrid, Electric Vehicle

While advanced power-train vehicle technologies make new vehicles more energy (fuel) efficient, moving a passenger safe 3000lbs steel box is energy intensive no matter how you do it. Since electricity is far less expensive per energetic unit than gasoline, electric vehicles cost less per mile to operate, but storing the electricity in expensive lithium batteries is the trade off that makes electric cars like the Nissan Leaf more expensive upfront. The long term operating cost of the Nissan Leaf per mile in terms of its electric fuel is really low at only about $0.035usd per mile, where a Toyota Prius has a operating fuel cost of about $0.086usd per mile. Operating costs aside, the mostly steel Nissan Leaf is an energy hog because it is made of steel, and the Prius hogs more energy that it would if it was made of aluminum because the Prius like most other mainstream vehicles is primarily made of heavy steel. When you factor in initial price, maintenance, insurance, depreciation, repair costs and all of the other comprehensive costs functions of operating a car, the Nissan Leaf acheives net total cost per mile parity with many normal vehicles.

Where is the all Aluminum Nissan Leaf? It would perform better, go farther and require less energy and thus less time to fuel up (charge). A lighter Nissan Leaf made of lighter materials would be better all around.

Where is the all Aluminum Toyota Prius? The steel in the Prius makes it heavy, not the 170lb NiMH 201.6v 6.5Ah battery and 72lbs of electric motors and 40lbs of electric controllers and computers and extra wires required for hybrid operations modes. The regular Prius would probably get much closer to 65MPG in the real world if it was made of aluminum instead of steel.

Less Steel More Aluminum Please

If automakers really want to reduce the energy consumption of their vehicles, they need to put them on an advanced material diet. Using advanced materials can shave hundreds of pounds off of a vehicle. The cost of making vehicles lighter however has prevented many mainstream vehicles and their operators from enjoying the all around benefits of materials like carbon fiber reinforced plastics over conventional materials like steel. Only exotic high performance supercars seem to be built with cool space age materials.

Regular sedans for the general public are sadly still made mostly of steel. Steel is heavy, and moving steel around is thus energy intensive. Fill a backpack with a large block of steel and try to wear it around... you get the point. An aluminum block of the same size would be much lighter and far easier to carry, while a carbon fiber block would be even lighter... you get the idea. Most vehicles are energy hogs because they weigh too much.

Pushing a Box through the Air

Many vehicles also waste energy because they are shaped approximately like a box, and boxes are not efficient at moving through air at high speed. If you look at aircraft, the hull designs should sing loudly a song about aerodynamic efficiency. Planes can only fly efficiently if they can cut through the air efficiently and the shapes of aircraft are designed to do exactly this: cut through the air efficiently. So why are vehicles shaped like a box? Safety and utility are two common answers given.

Minor aerodynamic tweaks are one of the low hanging fruits that automakers can nail without much cost or effort. Low rolling resistance tires are another low hanging fruit that can minimize energy waste and thus lower operating costs of any vehicle. Small fuel economy gains can be achieved with a smooth under body panel, efficient radiator inlet designs, aerodynamic side mirros and door handles and wheels. Some automakers offer eco-versions of their normal cars with minor aerodynamic tweaks that yeild one or two extra miles per gallon: allowing normal cars to reach the coveted 40MPG real world (on the highway) fuel economy rating.

Perspective on Progress:

It is a good time to be alive: lots of cool changes in the automotive and energy sectors are unfolding before our eyes. Better batteries, lighter materials, aerodynamic tweaks. If you have been reading my blog you can probably tell I am a gear head deep down. I love vehicles because America is so spread out. Vehicles extend your range and enable you to go places that are impractical to reach on a bicycle or on foot.

You can hold a web connected super computer in your hand now (smartphone)! Things sure have changed a lot and they will continue doing so as we seek to solve the problems created by sustaining billions of human lives simultaneously.

I will continue to let my wife use my Prius, and even she hopes to get a job within walking distance of our urban home soon. I roll Howard the Honda PCX these days and when it is a little warmer Ebert the Electric bike. It will be interesting to see how things unfold.

I am hoping that the Nissan Leaf's will depreciate like other vehicles so that I can pick one up used in the near future. As for the Prius, Meg and I are going to try and operate Astro the Prius for 400,000 miles; at the rate we have been driving that could take the rest of our lives, God willing ^^

The Tesla Model S is an all electric, long range, higher performance luxury sedan made in America by Tesla Motors in California. Thousands of Tesla Model S vehicles are in the hands of normal people out driving around roads all over the world. The Model S has raised the bar for every automakers and proved that electric vehicles can be fast, cool, luxurious, sexy and all around better than any gas powered vehicle in terms of the combination of value, utility, efficiency, and performance.

The Nissan Leaf is also an amazing vehicle. The price point of the Leaf is far more accessible, and used Nissan Leafs are readily available. Some think the battery will fade quickly, and for Leaf's operated in very hot climates this is sadly true. Lithium batteries are damaged by prolonged exposure to high temperatures. In cooler climates like the Northwestern United States where I live, the Nissan Leaf's battery capacity fades slowly and predictably, and will probably last 15 years if not abused by deep cycling, fast charging on level III units, and or overcharged to 100 on many of its cycles. If the Leaf battery is operated between 30% and 80% full and charged with Level II chargers and operated in a cooler climate, it will hold up for tens of thousands of cycles. If the Nissan Leaf battery is abused with fast charging, and deep cycling from full to nearly empty and exposed to prolonged periods of high heat then it will fade quickly and begin to fail in a critical way after several thousand cycles. So in my future hunt for a Nissan Leaf I will be looking for one from a geek that was really careful with the battery and that is going to be a challenge. The good news is that the "car wings" and "computers" on the LEAF and in its battery will tell me exactly how it was treated :)





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