Climate change was the subject of the Institution of Mechanical Engineers address delivered by Professor Richard Folkson, Chairman of the Automobile Division for the U.K. organization, at the recent SAE 2009 World Congress in Detroit. Acknowledging that there is some skepticism about climate change, he said he believes the gamble of not addressing CO2 emissions is too great a risk to bear.
“Engineers hold the key to solutions, and technology is capable of meeting the challenges,” he said. “But time is of the essence."
With evidence that CO2 emissions have grown from 280 ppm in 1750 to 375 ppm today, Folkson explained that “business as usual” will lead to CO2 concentrations greater than 1000 ppm. “Climate-change scientists believe we need to get down to around 450 ppm as the maximum that we can allow; otherwise, world temperatures will rise uncontrollably and make the planet un-inhabitable,” he said.
Folkson presented data showing that while the U.K. government targets 100 g/km of CO2 emissions by 2020, 70 g/km is more likely what is needed at current population and economic levels. He noted that the European Parliament passed new-car regulations that limit emissions to 130 g/km by 2015. “This is equivalent to achieving 58 mpg with a diesel engine and 52 mpg with a petrol car,” he said. There is some evidence that 30 g/km may be needed, he added.
While this rise in CO2 is all about energy consumption, the transportation industry can do only so much, he said. In the U.K., for example, land transport accounts for only 22% of CO2 emissions. Industrial processes, electricity generation, households, and air/sea transport account for much of the rest. All sectors must contribute to solve the problem, he said.
The solution must involve vast numbers and it must include advances in clean propulsion technology. “Fifty million cars are produced every year worldwide. We are not going to get there with niche products or just by tackling large cars and 4x4s or small volumes. It is millions of cars produced every year that is going to make a difference, not a few hundred thousand hybrids,” he said.
While various vehicle technologies can help, advances in propulsion hold the most potential for CO2 improvements, said Folkson.
Electric hybrids are getting lots of attention, he said, but much can be done via the conventional internal-combustion engine (ICE)—boosting and homogeneous charge compression ignition among them. Basic, solid engineering can deliver good results at an affordable cost.
"There is a Ford Fiesta that can drive at below 100 g/km just using conventional diesel engine technology," Folkson said. "No clever hybrids, no start/stop system. We are making a lot more progress with conventional technology than we thought possible three to five years ago."
Biofuels, hydrogen for use in ICEs, and hydrogen fuel cells are additional technologies at hand. Not discounting the contributions of all possible solutions, he pointed to biofuels as particularly virtuous in a “well-to-wheels” analysis, since the plants they are derived from absorb CO2. Also, biofuels are just as energy-dense as petroleum-based fuels, he noted while acknowledging that there are problems with first-generation biofuels derived from human food sources. The effect on food prices is a major concern. “I think second-generation biofuels, made from nonedible waste, really will make a difference and will tackle that concern about food,” said Folkson. Every major manufacturer should offer a solution. There is a sizable niche market opportunity."
Hydrogen as a fuel, when derived from renewable or nuclear energy sources, may offer the best long-term solution, he said, if technical challenges associated with low energy density and storage/distribution can be overcome. Liquid hydrogen is even more challenging, he said.
Hybrids should not be discounted, at least in the short term, Folkson said. “Hybrids are important. They provide one potential bridge to the next dominant powertrain.
In summarizing, Folkson said that while today’s challenges are real and difficult, "I actually think working on this issue of CO2 emissions and climate change is a way of pulling the automotive industry into the future with great technology that consumers are willing to buy.”