The Virginia Electric and Power Co., expressing "frustration" over nuclear power regulation, predicted yesterday that its fuel costs would soar to $1 billion next year, increasing customers' bills sharply.

The company proposed an increase in its "fuel factor" an amount reflecting rises in oil and other fuel costs -- that would raise electric bills for homeowners by about 12.7 percent over what the company has charged since October. The increase over last January would amount to nearly 40 percent.

A homeowner who paid $45.21 for electricity last January and is currently paying $55.89 for the same amount of electricity would be charged $62.99 a month starting next January under Vepco's proposal. The homeowner's monthly bill would increase to $69.35 in June when summer rates go into effect.

The figures are based on a homeowner using 1,000 kilowatt hours of electricity a month -- an amount described as close to the average for most of Vepco's 1.1 million Virginia customers. Owners of homes that rely on electric heating would pay larger bills. Their electric costs would rise by slightly higher percentages under Vepco's proposed fuel-factor increase.

Vepco's 1980 prediction, which amounts to a formal request, was required under a revised regulatory system established by the General Assembly in 1978. The State Corporation Commission has scheduled a hearing on Vepco's newly announced proposal for Dec. 13. A revised fuel factor is expected to go into effect Jan. 1.

Official of the State Corporation Commission and the Virginia attorney general's office said yesterday that they had not yet reviewed Vepco's proposal and could not comment on it.

Vepco's proposal yesterday was the latest in a series of complex requests for increases in the fuel factor in recent months. Any attempt to calculate how these increases affect an individual homeowners' electric bills is further complicated by seasonal shifts between lower winter rates and higher summer rates.

In August, Vepco officials warned that its 1979 fuel costs would rise by $91 million more than the company had been allowed to pass on to its customers by the State Department Corporation Commission, which regulates utility rates. The commission had already increased Vepco's fuel factor by $9.8 million in July and later authorized an addition $37 million rise, effective Oct. 1.

A Vepco spokesman said the company still seeks to recover $65 million more in fuel costs incurred this year through higher charges to customers.

Vepco officials attributed the steep increases in the companies fuel costs largely to skyrocketing oil prices and troubles plaguing the company's nuclear power plants. Oil costs climbed by more than 60 percent during the first 10 months of this year and will rise further shortly, the company said.

Vepco executive vice president William W. Berry reasserted the company's complaints about federal regulation of the nuclear power industry yesterday, noting that the Nuclear Regulatory Commission has delayed operation of North Anna 2, one of Vepco's four nuclear power units. If North Anna 2 were permitted to operate, Berry said, the fuel factor could drop from 1.6 to 1.25 cents per killowatt hour because of cheaper costs of nuclear energy.

"These uncertainties coninue to be a source of great frustration to us and we cannot eliminate them. They are the result of constantly changing requirements at the Nuclear Regulatory Commission," Berry said.

Because of the delays in operating North Anna Vepco officials have previously estimated, the company must spend between $11 million and $12 million a month for costlier fuels. The Nuclear Regulatory Commission has decided to postpone licensing new nuclear plants, including North Anna 2, until the commission establishes new safety and other standards.

Vepco officials say they hope to put North Anna 2 -- located in Louisa County on the North Anna River about 70 miles from Washington -- into operation by July 1. The company previously intended to start running North Anna 2 last summer.

Randy Phillips, a staff researcher for the Consumer Congress of Virginia, said yesterday that the group plans to raise several objections to Vepco's request for a fuel-factor increase at next month's SCC hearing. He contended that Vepco pays too much for coal and that the company should not be permitted to pass on to its customers the costs of buying fossil fuel to replace nuclear plants that are not in operation. A Vepco spokesman disputed both contentions.

Vepco estimated that its fuel costs would rise by 29 percent to slightly more than $1 billion next year from $778 million in 1979.