Just number folks...
The answer is perhaps as high as a hundred billion dollars.
From 1948 to today, nuclear energy research and development exceeded $70 billion, whereas research and development for renewables was about $10 billion. From 2002 to 2007, fossil fuels received almost $14 billion in electricity-related tax subsides, whereas renewables received under $3 billion.
..The benefit of this indirect subsidy has been estimated at between $237 million and $3.5 billion a year
testimony that nuclear power is "the beneficiary of some $100 billion in direct and indirect subsidies since 1948."
A 1992 U.S. Energy Information Administration (EIA) analysis, Federal Energy Subsidies: Direct and Indirect Interventions in Energy Markets [PDF], calls Price-Anderson, "A Federal regulation that continues to have a cost-reducing effect on the nuclear power industry." According to the EIA analysis:
EIA determined that the value of the subsidy to the nuclear industry as a whole was roughly $30 million per reactor per year, or $3 billion annually ($1991). The full subsidy value of the Price-Anderson Act from its inception through today thus likely exceeds a hundred billion dollars.