CHIBA -- Combining its cutting-edge engine and transmission technologies, Nissan Motor Co. has developed a new powertrain that it said can improve its vehicles' fuel economy by 50 percent and reduce carbon dioxide emissions by 35 percent.

Nissan introduced the new technology Tuesday at Nissan's first environment forum, held at Makuhari Messe. The carmaker has installed the new powertrain in its Primera and Bluebird models, which went on the market in Japan the same day.

The new Primera and Bluebird models are equipped with a 1.8-liter direct-injection gasoline engine and a new transmission called Hyper CVT (continuously variable transmission).

The engine directly injects fuel into the combustion chamber for what Nissan calls drastically improved fuel economy and high power output. Hyper CVT changes gears depending on driving conditions to achieve optimal fuel efficiency and provides smooth driving with no jerks upon changing gears, Nissan said. "We hope to develop it as a core technology and also try to promote its sales to other automakers," said Nissan President Yoshikazu Hanawa.

At the forum, Nissan Vice President Tsutomu Sawada said the company will try to develop a prototype of a next-generation fuel-cell vehicle by 2000 with the hope of marketing it between 2003 and 2005.

Because it does not emit carbon dioxide or other gases that contribute to global warming, fuel-cell power, which uses chemical reactions of hydrogen and oxygen to generate electricity, is widely viewed as a next-generation power-source by the world's major automakers.