A study released this week concludes that a new kind of engine technology -- Homogeneous Charge Compression Ignition (HCCI)--will power nearly 40 percent of heavy-duty vehicles by 2020. The study of powertrains of heavy-duty vehicles was conducted by TIAX, a product and technology development firm, and Global Insight, an industry forecasting firm. It predicts developments resulting in cleaner and more efficient engines through the use of self-shifting transmissions and hybrid heavy-duty vehicles. Unlike the traditional diesel engine, an HCCI engine emits almost no emissions of nitrogen oxides into the air. Nitrogen oxides are responsible for the creation of ozone, which can be harmful at ground level. Initially HCCI will only be able to power light loads at low speeds, so early versions of the engine will also incorporate conventional diesel combustion to supply more power when greater demand is placed on the engine. A full-mode HCCI engine that can meet all the demands placed on it by heavy-duty vehicles will eventually supersede the mixed-mode HCCI/Diesel technology, the report says. This finding is particularly significant in that the exhaust-gas treatment systems currently being developed and expected to reach the market in the next few years will start to become obsolete by 2020. The report also predicts that by 2020, 15 to 25 percent of heavy-duty vehicles globally will incorporate either hybrid electric or hydraulic hybrid technology. The report also says the demand for self-shifting transmission technology in heavy-duty vehicles will increase dramatically over the next 15 years. The use of self-shifting transmissions will broaden the labor pool from which drivers can be recruited because trucks with automated or automatic transmissions are easier to drive. The report's conclusions were reached using a step-by-step objective methodology to project the market for powertrain technology. Factors such as the availability of crude oil, probable technical developments, predictions of emission control legislation, and the financial impact of new technologies on vehicle costs were all analyzed. Discussions with industry experts and an analysis of future market conditions for each technology were undertaken to further refine the forecasts of the report, the companies said in a statement.