Trump said the administration will use authority under a Cold War-era national defence law to support 13 coal plants across the country and help build coal plants in Alaska and West Virginia - the first new US coal plants since 2013.
The money will also help restart a shuttered coal-fired power plant in Maryland and support construction of a long-delayed coal export terminal in Oakland, California.
Trump invoked the Defense Production Act, a 1950 law that grants presidents broad authority over national security-related industries, and said his actions will allow coal plants to invest in upgrades to extend their operational lives for decades.
The plan will "reinforce the reliability of our electric grid, which is really the biggest beneficiary," Trump said at a White House press conference.
"Coal's a great business. In terms of power, there's really nothing like it."
The announcement is the latest step by Trump to try to reverse the years-long decline in the US coal industry.
The administration said last year it would open 52 million hectares of federal land for coal mining and provide $US625 million to recommission or modernise coal-fired power plants.
Trump issued executive orders soon after retaking office to try to revive coal, a reliable but polluting energy source that's long been shrinking amid environmental regulations and competition from cheaper natural gas and renewable energy.
Under Trump's orders, the Energy Department has required coal-fired power plants in Michigan, Indiana, Colorado and Washington state to keep operating past their retirement dates to meet rising US power demand amid growth in data centres, artificial intelligence and electric cars.
Energy Secretary Chris Wright issued an emergency order on Thursday requiring a coal-fired power plant in Orlando, Florida, to remain open past a planned shutdown this month.
Wright repeated a claim the administration's use of emergency orders to keep aging coal-fired plants operating helped prevent major blackouts during brutally frigid weather that gripped most of the country in late January and early February.
Environmental groups denounced the latest efforts to boost coal, which come as the Trump administration has clamped down on renewable energy, including freezing permits for offshore wind projects, ending clean energy tax credits and blocking wind and solar projects on federal lands.
"Propping up coal billionaires with taxpayer money is one more way for the Trump administration to put polluters first and put the rest of us at risk," said Kit Kennedy, managing director for power at the Natural Resources Defence Council.
"What's next, a taxpayer bailout to build new phone booths?"
