In an action expected to mean millions of dollars in additional earnings for Virginia Electric and Power Co., the Virginia State Corporation Commission has adopted procedures that allow utilities to begin collecting limited rate increases 30 days after a request and before the commission rules.

Vepco's president and chief executive officer, William W. Berry, said Tuesday that the electric utility will file a request for a rate increase of up to 8.9 percent on March 31 using that procedure rather than filing under other rules that would allow Vepco to ask for an unlimited amount of money.

Utilities were notified of new procedures for asking that the increase go into effect in a month in a letter dated March 3 from Judge Preston C. Shannon, who handles utility cases for the commission, and Vepco moved quickly to take advantage of it. Vepco had suggested such a change when the SCC's staff asked for comments on procedures from several utility companies.

The notion of beginning to collect additional revenues almost right away is so attractive that it outweighs the drawback of having to ask for less and other restrictions, said Berry, adding, "That carrot more than offsets the stick."

If Vepco begins collecting the money and the SCC later decides the amount requested was too high, Vepco must refund the money and pay an interest rate set by the commission. Utility officials don't expect that to happen, however, in part because the request will be limited to what they consider modest dimensions.

Berry said Vepco has not yet determined exactly how much money it will ask for or whether it will ask for the full 8.9 percent next Wednesday when it files its request. If the SCC allows Vepco to begin collecting under the 30-day procedure, increased rates would go into effect about May Day.

Berry said he hopes the added earnings will help the utility to raise capital it badly needs, money that is difficult to raise in securities markets. "We need improved earnings so we'll be able to finance the capacity we need in the 1980s and 1990s," he said.

"We could ask for considerably more in a general rate case, but we'd get it considerably later," said Berry.

Filing a general rate increase is the alternative way Vepco could ask for higher rates. But under that procedure, the SCC allows increases to go into effect only after it acts, or after five months. That means that asking for more money would cost the utility company an extra four months without any increase coming in.

The new method that Vepco plans to use is called the Financial Operating Review procedure. In 1979, the General Assembly passed a resolution encouraging the SCC to establish procedures that would make it easier for utilities to keep up with inflation.

The result was the FOR, which was spelled out for the first time in a letter to utilities from the SCC in January 1980. Under the FOR, the amount of increase that may be requested is limited to the rise in the consumer price index for the previous year. The utility also is limited in other respects, including prohibitions for asking for an improvement on its return on equity or changing its rate design, Berry said.

The letter from Shannon was one of a continuing series of modifications of the procedure, according to SCC spokesman Jim Davis.