More than 6,500 customers of Virginia Electric & Power Co. have signed up to buy Vepco stock under the nation's first customer stock-purchase plan, the utility company announced last week.

Customers pledged to buy $3 million worth of Vepco shares in monthly installments, exceeding the $2.5 million minimum that Vepco said was needed to be economically successful.

When the plan first was announced, Vepco warned it might be canceled if customers didn't buy enough stock, but by last Wednesday, Vepco had enough commitments to go ahead with the sales, starting Sept. 1.

The plan requires participating Vepco customers to invest at least $10 a month in the utility's stock. The average monthly purchase turned out to be $40, also higher than officials expected.

Vepco customers who have signed up to buy stock will get a book of monthly payment coupons similar to those used on many installment loans. Every month they will mail in their coupon and their payment. After 12 months -- during which the funds will earn 8 percent interest -- the money will be used to buy Vepco shares.

Customers will get their Vepco stock at the average price during the year. They will not pay the usual stock purchase commission but will pay part of the cost of running the program.

Vepco has estimated the charges will be less than 10 percent of the cost of the stock.