* New facility to draw on Germany, India truck resources
* Included in 2.5 bln euro truck division investment
* Daimler to expand e-truck line-up to meet emission goals
* Eyes strong H2, challenging Q2 -CFO (Adds details on Tesla Semi, VW/Navistar electric truck)
FRANKFURT/PORTLAND, Ore., June 6 (Reuters) - Daimler AG unveiled on Wednesday an all-electric big rig truck it promises to have in production in 2021, as the German automaker mounts a major challenge to European manufacturers and Tesla Inc.
Daimler said its Freightliner eCascadia, with a range of up to 250 miles (400 km) and an 80,000 lb (36 tonne) gross combined weight, will be suitable for regional distribution and port shipments.
Daimler also unveiled a medium-duty Freightliner eM2 106, with a range of up to 230 miles, designed for local distribution, food and beverage delivery, and "final-mile" logistics services.
Daimler said it will deliver 30 vehicles to customers later this year for field-testing and expects to have the trucks in production by 2021.
Tesla has said it expects to begin production of its all-electric Semi in 2019. Other truckmakers, including Navistar International Corp and its partner Volkswagen AG , also are working on similar models.
Industry analysts believe the main market for such trucks could be China.
A heavy-duty commercial truck runs up to 100,000 miles a year, and Tesla has promised a 20-percent saving on current per-mile operating costs.
Analysts have said truck operating costs continue to fluctuate and Tesla's projected savings may not be so great. There are also concerns about the charging infrastructure and operating range of electric trucks, which could be much less than current diesel-engine models.
The announcement came after Daimler's trucks division said it has set up a research and development center for autonomous driving in the United States, the latest sign of the German manufacturer's commitment to getting self-driving freight trucks on the road.
Engineers at the new facility in Portland, Oregon, will draw on R&D resources at Daimler Trucks operations in Germany and India to create a global network of hundreds of specialists in the autonomous driving sphere, the company said on Wednesday.
Stuttgart-based Daimler will invest more than 2.5 billion euros ($2.9 billion) in R&D at its truck operations by 2019, with more than 500 million euros earmarked for electric heavy-duty commercial vehicles, connectivity and self-driving technology, including the new Portland facility, it said.
"We are pioneering technologies across the automated vehicle spectrum that make roads safer and help trucking companies boost productivity," said Sven Ennerst, head of truck product engineering at Daimler.
The announcement was made during the Daimler Trucks Capital Market and Technology Day at Portland where the division already has a significant R&D presence including a heavy-duty truck wind tunnel.
Daimler also plans to expand its line-up of battery-powered trucks to help comply with tougher carbon dioxide (CO2) emissions rules in Europe, said Martin Daum, head of the division.
Serial production of the eActros truck with an operating range of up to 200 kilometers (125 miles) will start in 2021, said Ennerst, citing tests with other models including the eFuso and eCanter trucks.
A presentation revealed that Daimler has plans for more than a dozen further electrified trucks worldwide, including the new eCascadia model for North America to compete with Tesla's planned long-distance Semi electric truck.
Separately, Daimler Trucks expects a strong second half of the year but second-quarter business remains challenging, its finance chief said, citing problems in the supply chain.
"We are currently facing some problems on the supply chain. We will not lose a single truck but some (trucks) might be invoiced in Q3," Jochen Goetz said.
A new efficiency programme will not be needed, Goetz said, adding the truckmaker would focus on executing its previous savings plan and aim to lower costs by 1.4 billion euros as planned by 2019.
($1 = 0.8490 euro) (Reporting by Ilona Wissenbach in Frankfurt and Eric M. Johnson in Portland, Oregon; additional reporting by Ilona Wissenbach in Frankfurt; writing by Andreas Cremer; editing by Mark Potter and Lisa Shumaker)