Nissan Leaf: ET-IT

EV-IT With the Nissan Leaf

by Steve Auger

Touting a range of 100 miles on a single charge, the zero emissions Nissan Leaf is poised to become an early leader in the field of Electric Vehicles (EV).  In a bold move, Nissan decided to eliminate the alternate power source (gasoline), a feature on Nissan's prime competition, the Chevy Volt.  By so doing, they have eliminated weight, making the vehicle more efficient, and optimized space, allowing more room for batteries and interior design.  And there is the lower price tag, not to be underestimated in this ensuing battle for market share.

What are the negatives for the elimination of gasoline as secondary power source?    One downside is that the Nissan Leaf sacrifices the ability to go on a long trip (100+ miles).  It is a car strictly meant for short drives with long wait (8-16 hour) recharge cycles.  . 

The second and perhaps bigger downside is the potential for being stranded with a dead battery.   The Chevy Volt should never leave a motorist stranded simply because it has gasoline power as an alternative.  In addition, GM has described in great detail the engineering that thas gone into their Lithion Ion battery, a battery technology that has given cell-phone manufacturers fits for several years.  This is in contrast to Nissan, a company that has been relatively quiet on how they plan to make Lithium batteries operate reliably for multiple years. 

In any case, Nissan has a problem to overcome.  And that problem is the worry for motorists of becoming stranded in the middle of nowhere.  And the only option is to be towed to a recharging station.

Nissan is attempting to overcome this worry by providing an advanced Information Technology (IT) capability that will work with the car's navigation system.  The navigation system will calculate whether or not the vehicle is within range of a recharging system such as your home, (possibly) office or a commercial charging station.  In addition, the navigation system will show the driving radius for the car's current state of charge.

Drivers will also be able to monitor the vehicle;s state of charge by cell phone and online.

Whether or not the IT features available with the Nissan Leaf eliminate consumer worries remains to be seen.  But you can be sure I won't be buying first generation technology :)

Electric Vehicles

Electric Vehicles:  A Better Environmental Choice

EVs are 24% Efficient

According to Transport Watch, only about 30% of the energy generated by a power plant in fact reaches an Electric Vehicle (EV) because of losses in the transmission route.  Of the energy delivered to the vehicle, 20% is then lost to the batteries and electric motor. This means that most EVs are only about 24% efficient. So, if your electric vehicle is charged with electricity from a coal-fired power plant, then the CO2 emissions to fuel your EV are about double the amount emitted by a diesel engine, due to the inefficiencies in electrical power generation and transmission.

So they conclude that the notion that electric cars will reduce emissions is fiction unless we hypothecate that the UK electricity generating industry will be de-carbonised.

Power Generation and Transmission Are Important Factors

But if we want to consider this issue carefully, we will find that the electric vehicle is environmentally friendly and efficiencies in electrical power generation and transmission.  First, let us consider some definitions:

• Hybrid-electric vehicle (HEV): This uses an internal-combustion engine for most of its power, but also has an electric motor run from batteries recharged by the engine. Typically the engine shuts off whenthe car is stopped. HEVs include the Toyota Prius and the Honda Insight.
• Plug-in hybrid-electric vehicle (PHEV):  An HEV that can charge its batteries by plugging into a charger, permitting all-electric short trips. The forthcoming Chevrolet Volt is such a car.
• Battery-electric vehicle (BEV): an electric car powered only by batteries.
  

All three can charge their batteries using regenerative braking, which recaptures energy otherwise lost as heat when bringing the car to a stop. That’s a big benefit for electrics.

Power Transmission

How much energy is lost getting electricity from the power plant to your PHEV or BEV?   Plenty. In the U.S. right currently, about 70 percent of the energy used to make electricity - more than four million gigawatt-hours - comes from fossil fuels. About 70 percent of that amount is wasted generating the power and transmitting it to your door. Additional energy is lost when charging batteries and operation electric motors. Generally, electric cars use fossil fuel at 20 to 25 percent efficiency, but dismal as that sounds, it beats an internal-combustion car, which usually operates at about 15 percent efficiency.   An HEV uses around 0.48-0.74 kilowatt-hours per mile, while PHEVs in electric mode and BEVs use 0.18-0.46 kWh per mile.  By contrast, a conventional car getting 25 MPG uses 1.35 kWh/mile. To put the issue in more well-known terms, a PHEV or BEV offers fuel economy equivalent to as much as 188 miles per gallon.

Pollution

Now let’s talk pollution.  A huge advantage of PHEV and BEV cars is that their energy can come from renewable sources, such as hydroelectric, wind, or solar.  Even if the energy source is fossil fuel, installing state-of-the-art emission controls on a few big power plants is way easier than installing ’em on hundreds of millions of motor vehicles. What’s more, since many electric plants use natural gas, carbon dioxide emissions from power generation are a modest 1.27 pounds of CO2 per kWh - 1.9 pounds per productive kWh once we account for losses during battery charging and so on.   Compare that to gasoline, which produces the equivalent of 3.9 pounds of CO2 per productive kWh.

EV Batteries:  A More Environmentally Friendly Alternative

The electric car battery is far more environmentally friendly than conventional car batteries.  For example, Tesla's Electric Roadster Battery can maximize the amount of materials that can be reused, recycled, and minimize energy consumption utilized during the transportation and recycling process.  They can separate the elements and re-use what can be re-used (cobalt, aluminum, nickel, and copper, etc). So the battery pack saves thousands of gallons of gasoline/diesel over the life of the vehicle, it is less toxic than the lead-acid batteries that are in regular cars, and at the end of its life it is recycled.