Speaking at the Limerick Generating Station nuclear plant in Pennsylvania, Mr Bush said that the US must diversify its energy sources.
"For the sake of economic security and national security, the United States should aggressively move forward with the construction of nuclear power plants," Mr Bush said.
The US President re-entered into the energy debate just as a documentary about global warming, “An Inconvenient Truth”, featuring Al Gore, who lost to Mr Bush in the 2000 presidential election, opens in US theatres this week.
"Nuclear power helps us protect the environment. And nuclear power is safe," Mr Bush said to loud clapping from the audience.
Petrol prices
Grappling with public anxiety over high US petrol prices, Mr Bush has this year been emphasising a need to coax America from imported oil and devote more resources to developing alternative fuels. He acknowledged people are right to be concerned about greenhouse gas emissions.
"I understand why. I am too," he said. "As a matter of fact I try to tell people let's quit the debate about whether greenhouse gases are caused by mankind or by natural causes. Let's just focus on technologies that deal with the issue."
He said nuclear power is one such technology that "will help us deal with the issue of greenhouse gases" and that the US should move aggressively to build new atomic power plants.
But critics are concerned that nuclear plants carry too many risks.
"We hope the administration and the Congress will acknowledge the severe threat to our nuclear power plants because of inadequate security, excessive government secrecy and a lack of whistle-blower protections for nuclear plant employees," said Danielle Brian, executive director of the Project On Government Oversight.
New nuclear plants
The US Nuclear Energy Institute, an industry trade group, anticipates utilities will build 12 to 15 new nuclear plants by 2015 to join the current 103 power reactors.
A new 1,000 megawatt reactor may cost from between $A2 billion to $A4 billion. One megawatt provides power for about 800 homes.
The last nuclear plant built in the United States was Ameren's Callaway station in Missouri, which was licensed by the Nuclear Regulatory Commission in 1973 and began operations in 1984, according to the NEI.
The Three Mile Island accident in Pennsylvania in 1979 and the Chernobyl disaster in Ukraine in 1986 heightened safety fears and effectively halted new reactor construction in the United States.
Nuclear power generates 20 per cent of US electricity, up from three per cent in the early 1970s.