As California develops a plan to cut greenhouse gases, companies hope that better methods to measure and record emissions reductions can allow offsets to play a major role. Emissions offsets have long been used as a low-cost way to cut conventional smog-forming pollution. However, their reputation for cutting greenhouse gases has been sullied in Europe due to doubts about the authenticity of emissions reductions from offset projects in the southern parts of the globe. Offsets involve a company meeting a pollution reduction requirement by cutting emissions--not at its own plants, but in other locations. For instance, a power company might opt to pay to convert shuttle buses used at an airport to cleaner fuels in lieu of installing more expensive pollution control equipment at its generating plant. Offsets also can be traded, making it possible for third-party companies to develop projects that cut emissions more than required under law, and then sell the resulting emission reduction credits to companies that have to cut their own pollution. To aid in making such carbon emission reduction credits acceptable to regulators, the California Climate Action Registry introduced new verification procedures for offsets earlier this month. Meanwhile, one company that is emerging as a leader in providing authenticated domestic carbon offsets to major industries is Blue Source. The Utah-based firm has a broad portfolio, which includes CO2 sequestration projects at gas processing plants; methane capture projects at landfills, coal mines, and wastewater treatment plants; and emissions reductions from transportation. While it is easy to measure the flow of CO2, or methane, from a stationary plant, it is trickier to measure what is going on in vehicles, which could be a leading supply of offsets for the power industry in California. After all, transportation is the state\u2019s biggest source of greenhouse gases. Blue Source apparently has devised a method to do so. In a project with J.B. Hunt, Blue Source has managed to cut 25,000 tons a year of CO2 emissions from diesel trucks by minimizing the amount of time drivers idle their big rigs. The key to the authenticity of the resulting offset credits is a high-tech system that monitors drivers to get around the possibility that they might turn in fudged logs on idling time, explains Mahesh Gundappa, Blue Source vice president of engineering. The program to minimize idling began in 2003 as part of a wider effort with J.B. Hunt to minimize truck emissions through better logistics planning, use of biodiesel fuel, and other measures. This wider effort has cut CO2 emissions by up to a million tons a year, according to Joe McGurk, Blue Source spokesperson. The idling program is aimed at trimming engine use to keep cabs warm or cool when drivers park at truck stops to rest. In the program, idling is monitored by an onboard device that transmits a signal to a computer that maintains a log of idling hours for each truck. The signal also provides the exact location of the big rig. This is important, Gundappa said, to avoid taking credit for emissions reductions that would occur anyway, given that some areas, like California, have adopted regulatory limits on truck idling to cut air pollution. At first, the devices were used to measure normal idling behavior of J.B. Hunt truckers. After determining their baseline behavior, the company set a goal for reduced idling and began providing incentive pay to drivers who could meet it, said Gundappa. The devices then were used to measure how idling changed. The resulting credits are sold in existing carbon exchanges to companies that need to reduce their emissions due either to regulations or to meet voluntary goals. The proceeds are being plowed into further investments in cutting carbon emissions from J.B. Hunt operations, according to Blue Source. Environmentalists envision using similar technology on cars to monitor the behavior of motorists. Those who minimize idling and drive in a more fuel efficient manner would get financial incentives--just like the J.B. Hunt drivers--in the form of discounts on vehicle insurance or registration fees. Those who are heavy on the gas would pay more.