Shutting down the Indian Point nuclear power plant would lead to significantly dirtier air and higher electric bills for New York City residents, according to a report commissioned by the city that is circulating among state officials in Albany.

The report, a copy of which was obtained on Tuesday by The New York Times, concludes that, for the next several years, there probably will not be enough new power generated to replace the 2,000 megawatts produced by the two reactors at Indian Point. That shortfall could leave the city with a less reliable supply of electricity and a greater risk of brownouts, the report finds.

Those findings buttress the stated views of Mayor Michael R. Bloomberg, who has said that Indian Point probably cannot be shut down “for the next four or five years.” That position could leave him at odds with Gov. Andrew M. Cuomo, who has told executives of Indian Point’s owner, Entergy, that he was determined to close the plant, which stands along the Hudson River about 35 miles north of Midtown.

The licenses for the plant’s reactors are scheduled for renewal in 2013 and 2015. Together, the reactors produce as much as 25 percent of the power consumed in Consolidated Edison’s service area, which includes New York City and Westchester County.