HANOVER, Germany (Reuters) - Major manufacturers, such as Daimler Truck and Traton, displaying their trucks at a transportation fair in Hanover this week say they are ready to go electric, but their e-trucks will not sell without massive investments in charging infrastructure.

Christian Levin, chief of Volkswagen's truck subsidiary Traton, which owns such brands as Scania, MAN, Navistar, and Volkswagen Trucks and Buses, said the European Union's goal of reaching a 50% share of e-trucks 2030 for now looks out of reach. "It's not just about cost, it's also about charging infrastructure, permissions, green electricity, supply of green electricity, and of course pricing. All of that needs to come together," he told Reuters in an interview.

Daimler Truck's incoming CEO Karin Radstroem had a similar message.

"The trucks are ready and now infrastructure must follow," Radstroem said at Daimler's presentation at the IAA Transportation truck show.

"When the infrastructure is not ready, clients won't buy and when our clients are not buying, we'll need to delay the Green Deal."

EU rules say manufacturers have to reduce the CO2 emissions of new heavy trucks by 45% by 2030, compared to the 2020 levels or face stiff fines.

To meet the EU's targets, the share of emission-free heavy trucks should rise to 40% of new sales by 2030 from below 2% today, a study by consultancy firm McKinsey showed. Prices of emissions-free trucks would need to halve to make them a viable alternative to diesel models, McKinsey said.

Almost 35 billion euros ($38.99 billion) must be invested in charging infrastructure across Europe by 2035 to meet the logistics industry demand, a study by consultancy PwC found.

Daimler Truck's technology chief Andreas Gorbach suggested that the EU targets should be coupled with the pace of infrastructure development and revisited every year depending on progress.

"In the past, somebody had to build the highways to have trucks on them... and the highway of the future is the charging infrastructure," Gorbach told journalists at a press conference on IAA on Monday.

"Now it is the time to switch gears, otherwise it becomes unrealistic," he said.

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