Automobiles (Global Warming)

Ten billion metric tons of carbon dioxide and other greenhouse gases are spewed into the atmosphere each year by the fossil fuel-hungry transportation sector. Over the typical 124,000-mile lifespan of an automobile, the Toyota Prius will emit 32 tons of carbon dioxide from its tailpipe versus a Ford Excursion spewing 134 tons.

The type of transportation employed has a major impact on the amount of carbon dioxide and pollutants produced. People can choose their mode of transportation and whether or not to be a part of a growing community that wants to reduce the effects of global warming by cutting back on tailpipe emissions. The internal combustion engine (ICE) is a poor choice of power source. It dissipates 80 percent of its energy as heat, even before it reaches the vehicle’s rear axle. Two major approaches to reduce the threat of global warming have emerged in the automobile industry. The first approach encompasses both conservation and new technology. A proven idea is increasing vehicle efficiency at a greater rate than has been done to date. The automobile industry can also develop new vehicle technology beyond the gas-electric hybrids. Introduction of Pluggable Hybrid Electric Vehicles (PHEVs) that double the range of current hybrids and further reduce greenhouse gas tail emissions is on the horizon. Utility operators already know that they can handle the additional demand expected of the power grid, since most PHEV owners would plug in their cars at night to be recharged, when demand for 120-volt supplies is low. All that is needed is improved battery technology and the will of automakers.

A second strategy is to develop alternative fuel supplies to power vehicles. Ethanol-blended gasoline, such as E85, is appearing on the market. New American cars work with this fuel which is 85 percent gasoline and 15 percent ethanol. Vehicles manufacturer-certified to burn E85 produce less carbon dioxide is produced combusting this fuel than burning regular gasoline, in spite of the CO2 needed to produce the ethanol in the first place. Engine performance is boosted with E85, too, with some vehicles realizing a horsepower gain of up to 5 percent. One major advantage is lowered tailpipe emissions. Other mixtures are being developed, including the use of liquid hydrogen as an alternate source.

While many of these actions are voluntary, regulatory action is often required to raise mileage standards. In the United States, more stringent Corporate Average Fuel Standards (CAFE) spurs development of energy-efficient components and solutions for personal mobility. To achieve new goals for greater miles per gallon, and, hence, lower greenhouse gas emissions, more fuel-efficient engines and transmissions are needed for conventional gasoline-powered or diesel-powered vehicles.

BMW automobiles, a company that does not have a gas-electric hybrid on the market, is also contributing to better fuel efficiency. It developed a brake energy regeneration system as a result of an internal project to provide intelligent alternator control. Every car on the market uses an alternator to continuously generate power, regardless of the engine load. Known as "alternator drag," the alternator consumes energy even when the car is cruising or accelerating, a process referred to as freewheeling. If the alternator only generates power during the braking cycle, the amount of fuel consumed overall is reduced. BMW expects its brake energy regeneration system to cut energy consumption by 3 percent on every car that adopts the technology. The conventional energy cycle can be deconstructed, analyzed, and subsequent innovations can deliver better miles per gallon for the driving public.

Hybrid and electric vehicles

Hybrid vehicles are available today and continue to gain market acceptance. Toyota’s Prius has been the overwhelming favorite of the car-buying public interested in gas-electric hybrids. The first 100,000 Prius gas-electric hybrids were sold by September 2004, after the introduction of the car in Japan in 1997. While it took almost seven years to reach the first 100,000 sales, a five-fold increase was achieved in about 18 months. By April 2006, Toyota’s worldwide sales passed 500,000 units. Momentum continued to build, and after another year had passed, Toyota exceeded the one million mark in sales. The Prius is a market hit, and the gas-electric hybrid technology for fuel efficiency and reduced greenhouse gas emissions has gained consumer acceptance. Electric vehicles that were popular at the turn of the 20th century are making a comeback in the 21st century. Two entrants come from Tesla Motors, the Roadster, a high-end sport car for the elite buyer, and Think, with their City car, a working everyday runabout. Think is working to fulfill a vision of producing a carbon-neutral vehicle. The Think City has a range of 112 mi. (180 km.) on a single charge, regulated at a maximum speed of 62 mi. (100 km.) per hour. It is ideal for local driving, easily exceeding the typical 50 mi. (80 km.) a day that most people drive.

A gas-electric hybrid, for example, a Toyota Prius, will emit only 32 tons of carbon dioxide from its tailpipe over a typical 124,000-mile automobile lifespan, while a Ford Excursion will discharge over 100 tons more.

Associated with an aspect of sustainability is the vehicle’s battery, the major expense in any electric vehicle. It is expected that battery-leasing companies will appear to make vehicles like the Think City affordable to a wider audience. Utility operators can use batteries no longer suitable for transportation, but still retaining a useful charge, in their power facilities to store excess energy produced by renewable sources such as solar and wind. Many governments are offering some form of rebate incentive to go green and help improve local air quality, regardless of the type of gas-electric hybrid or electric vehicle driven. For example, the Canadian province of Manitoba initiated a $2,000 rebate program to offset the higher cost of gas-electric hybrid vehicles versus comparable "dirtier" vehicles. The objective was to increase the number of hybrid vehicles from a paltry .01 percent of vehicles operating, to some greater percentage that would help reduce greenhouse gas emissions.

A July 2007 joint study by the Electric Power Research Institute (EPRI) and the Natural Resources Defense Council (NRDC) reports that even with marginal reductions made to existing power plant emissions and acceptance of gas-electric hybrids on the order of 20 percent of the driving public by 2050, 163 million tons of greenhouse gas emissions would be cut. This worst-case scenario is great news for hybrid advocates, especially those pushing for PHEVs. In a better case scenario, where more aggressive pollution-control measures are invoked on utilities and where hybrids garner over a 60 percent share of the market, 468 million tons of greenhouse gases can be spared from the atmosphere. This translates into removing more than 80 million cars from the highways.

In early 2007, it was reported that a standard Prius converted to PHEV doubled its gas mileage range. One 51 mi. (82 km.) trip netted an efficiency of 124 mi. (300 km.) per gallon at a cost of a penny in electricity per mile. The conversion to PHEV delivered a huge reduction in gas consumption of just over 60 percent, while emitting about two-thirds less greenhouse gases. Total cost was $1.76 in gas and $0.51 electricity versus the $3.17 in gas it normally cost. PHEVs contribute lower CO2 emissions, because they do not burn fossil fuels directly, but take electricity from a mix of sources produced by the utility. In a more typical comparison with conventional ICE vehicles, a standard Prius will release one-third less carbon dioxide than a large sedan into the atmosphere.

HYDROGEN-POWERED VEHICLES

In terms of reducing automobile pollution, each generation of new pollution control technology, since the days of the catalytic converter, has been pioneered by California. A recent plan for a California Zero Emissions Vehicle (ZEV) is spurring the development of new technologies, including hydrogen-powered automobiles. To run these, hydrogen fuel can be derived from fossil fuels (which defeats their purpose somewhat), biomass, or electrolysis of water. The most popular feedstock for producing hydrogen is natural gas. Using renewable alternatives, such as photovoltaics or wind to produce hydrogen, runs at three times the cost of other techniques. If the electricity for electrolysis comes from coal-fired plants, the CO2 emissions are even greater than those from natural gas, unless the carbon can be sequestered. All things being equal, hydrogen produced from the electrical grid would produce a net increase in global warming for the next 20 years. Coal gasification can also be used to produce hydrogen.

Given that the economics to produce hydrogen dictate the selection of a fossil fuel feedstock, it makes a big difference how the carbon dioxide is produced. An internal combustion engine produces 248 kg. of carbon dioxide for each 600 mi. (966 km.) driven. Table 1 reflects the reduction in kilograms possible by using alternate forms of transportation:

Table 1

Hydrogen is used in fuel-cell vehicles (FCVs), which are a potential replacement for ICEs. Hydrogen is converted to electricity, without high temperature reactions and is done so very efficiently. Only water vapor is produced, a byproduct that is less harmful to warming global temperatures than carbon dioxide, methane, or chlorofluorocarbons (CFCs). Every major car manufacturer has a FCV prototype, and many have FCVs on the roads in places like California, Washington D.C., Japan, and parts of Europe.

It is expected that FCVs will appear when the following issues are resolved: high cost of fuel cells, overcoming poor fuel cell durability, improving onboard fuel storage to ensure comparable or better driving range, meeting and exceeding safety standards and demonstrating such, and ensuring there is an infrastructure to produce and distribute the hydrogen to large numbers of the driving public.

BMW’s Hydrogen 7 or H-7 is a bifuel vehicle using an internal combustion engine that is propelled by either gasoline or hydrogen. It is a transitional vehicle that could be introduced to bridge the gap between the scarcity of hydrogen fueling stations today and their expected abundance by 2030.

INVESTMENT AND CHOICES

Chemical battery breakthroughs are needed to improve energy storage capacity and length of storage times, which are critical for hybrid vehicles to make the transition to PHEVs. Superior battery performance is also needed as electric vehicles begin to reappear after a more than 100-year absence. Continued investment in a hydrogen infrastructure that weans humanity from fossil fuel sources is a worthy long-term goal that can pay big dividends for the patient investor.

Furthermore, simply increasing fuel economy on existing vehicles can save millions of gallons of oil each year in the short term. This can be done without future hydrogen vehicles or all-electric vehicles making any contribution. Market pressure is making these types of investments happen faster than government regulations.

General Motors lost its position of market dominance by ignoring customer demands for gas-electric hybrids or evolving its early generation electric vehicle. No government bailouts are expected for American automakers, and there is little hope that continued lobbying for lenient mileage standards would be successful.