U.S. President Donald Trump on Tuesday promised to announce more energy projects during a visit here, as he sought to draw support from hundreds of workers at a local factory.

"My administration is clearing the way for other massive, multi-billion-dollar investments," Trump told the audience, referring to the Shell petrochemicals complex as "just the beginning."

Trump later told the press during a tour of the factory that Secretary of Energy Rick Perry will be "announcing a big project next week."

Trump displayed clear favor for conventional energy over renewable energy, calling natural gas "powerful, clean and affordable" while criticizing windmills for destroying property values and killing "all the birds."

At times Trump's speech closely resembled the ones he had delivered at rallies, in which he blasted Democratic presidential nominees and railed at foreign countries for treating the United States unfairly.

Trump's speech was met by both cheers and indifference. Some workers were glued to their smartphones throughout the speech, and the crowd grew restless after the speech ended when told they weren't allowed to leave until Trump wrapped up the tour and his motorcade left.

Pennsylvania will be a vital state for Trump as he seeks re-election next year. He received about 45,000 more votes than his opponent Hillary Clinton in the 2016 elections, clinching the state's 20 electoral votes that helped him nail the race.