With every purchase of a Toyota Prius or discovery of a new alloy or element that could be used for efficient engine design, our world has been gradually compensating for the vast pollution we have built up over generations. The United States, which is the second-largest emitter of carbon dioxide behind China, lists the reduction of greenhouse gas emissions as one of the greater challenges that we face, as our economy has relied on fossil fuels as a central form of energy production since the Industrial Revolution.
A recent study by the National Research Council has found that it is possible for the United States to cut automobile emissions by 80 percent by 2050. While this is a lofty goal to pursue, this will become increasingly likely through technological advancements, a focus shift to alternative fuels and strong government policies that can subsidize high costs and sway consumer preference.
As observed in countless tests and reports from current users of hybrid automobiles, introducing energy efficient vehicles onto the roads can greatly reduce greenhouse gas emissions. Researchers are therefore continuously looking into cleaner forms of energy and methods for reducing the amount of energy input per work done in engines. At the same time, they are interested in increasing the engine efficiency by reducing the amount of wasted energy. They have tested many variables, including aerodynamic and rolling resistance and weight to optimize energy.
However, according to predictions published in this study, the 80 percent reduction of gas emissions will not be reached at the rate of current technological advancements. By 2050, cars would have to have an average of 180 miles per gallon.
A solution to this problem is to introduce cars that are powered by different types of alternative fuels, as seen in hybrid electric, plug-in electric, battery electric, hydrogen fuel cell electric, and compressed natural gas vehicles.
The problem with vehicles that reply on alternative fuels is their exorbitant cost. In fact, they cost several thousands of dollars more than conventional vehicles. Other problems with getting consumers to purchase electric cars is that vehicles powered by electricity can have smaller driving ranges, be difficult to repower or require a bulky energy storage method. Many locations are also still devoid of recharging stations.
The researchers anticipate that getting a significant number of these cars on the road by 2050, which is necessary to accomplish reach 80 percent emission reduction, will require government policies in order to encourage consumers to purchase them.
Alternatively, there seems to be great potential in using biofuel, particularly that made from lignocellulosic biomass-crop residue such as wheat straw, switchgrass, whole trees, and wood waste. Biofuel could be used as a direct replacement for gasoline without making significant changes to the technology that cars already use. Using electricity as a replacement for gasoline faces more challenges: the production of more electricity will put strain on the electric power grid and a dependence on batteries.
The current batteries used for electric vehicles puts a limit to driving range and also has a long recharge time. Using hydrogen as a fuel also has its own problems: although water is the only thing waste product from a hydrogen-powered vehicle, there are greenhouse gases involved in the production of hydrogen fuel. While these engines have proved effective, the major issue to introduce them in the market is their overall production cost.
Therefore, a new hydrogen cell design for cars needs to be developed if this alternative were to become competitive in the future market. If this can be done, hydrogen-fueled cars may be less expensive than the average internal combustion engine vehicle by 2050.
The researchers involved in the report acknowledge that the progress of alternative fuels will require significant steps in technology development. They believe that these developments should be encouraged by both government and industry. They suggest that strict policies including increasing fuel economy standards, subsidies, public information campaigns, and regular performance evaluations, will help the market, while industries will continue to research new designs for clean, energy-efficient engines.
