Many cities of electric power companies contend that too many generating plants are being constructed, at huge cost to the consuming public.

In a new era of conservation, expansion of power producing facilities could be scaled down, it has been argued.

If such an attitude is translated into public policy, however, the United States "is going to be limping into the next century" with inadequate energy to power homes and industry, in the view of T. Justin Moore Jr.

Moore is the new man in the hot seat as chief executive officer of Virginia Electric & Power Co. In an interview, he noted that, despite all of the conservation efforts of recent years, peak demand for Vepco electricity in 1977 soared some 12 per cent over the previous year to a record 7,902 megawatts.

Generating facilities must be in place to meet the annual peak demand of any electric unity; in the case of Vepco, the peak day typically is hot and muggy; and air conditioners are turned n to maximum output from the suburbs of Washington to Tidewater Virginia.

The sharp spurt in peak demand in Vepco's service area was "above the highest estimates" made by the company and should be a warning to all customers served by the company of the need for significant expansion, he asserted. "We must build a new Vepco every seven years," said Moore, who took over Jan. 1 as vice chairman and chief executive of a company that has been under siege.

But the harsh attacks on Vepco in recent years would be minor compared with what would have been the response had the company had not expanded in earlier years and a power failure had occurred in Virginia last year, he noted.

In the electric utility business, "You'll never persuade people to love you," Moore added.

Vepco is the natio's eighth largest electric utility, providing power to one of the fastest-growing regions on the continent - heavily populated areas of Virginia, plus northeastern North Carolina and a small section of West Virginia.

Vepco economists and planners are forecasting that peak demand for power in this region will grow by 5.5 per cent a year between now and 1986, and they have wrapped into their estimates a significant amount of conservation and new methods of pricing designed to discourage power consumption at periods of peak demand.

Moore and his subordinates believe they will be able to generate or buy enough power to meet the increasing demand, but they are somewhat cautious about this coming summer and are a bit worried about 1981.

Vepco is forecasting that its total output capacity in 1978 will be nearly 13 per cent above projected peak demand - below the optimum level of more than 15 per cent. And, in 1981, the extra reserves are projected at less than 12 per cent above expected peak demand.

Moore, who has replaced former chief executive John M. McGurn in preparation for the latter's planned retirement as chairman next October, said the lower reserves next summer are due to necessary shutdowns to replace defective steam generator assemblies at its Surray plant.

The problem of potential power shortages in 1981 will be nationwide, in electric plant expansion during the 1974 energy crisis in an industry where planning for new plants must be conducted up to a decade before operation.

Moore said the sharp upswing in peak demand last year propably was an abberatin, partially reflecting economic recovery from the recent necession. In the year 1957 through 1973, peak demand grew by an average 10.8 per cent a year. From 1974 through 1976, demand declined at peak periods although total output rose both in 1975 and 1976.

Last year, peak power demand across the country rose to a record level, according to an industry trade group, the Edison Electri Institute. Peak demand was up 6.5 per cent in 1977 after a 4 per cent rise in 1976.

Edison president W. Donham Crawford said the resumed growth in demand for power indicates that consumer conservation measures must be pursued, that construction of new coal and nuclear-generating stations must be permitted and that incentives should be provided to facilitate raising capital to construct new capacity.

Vepco is virtually a classroom example of the industry's past and future problems. In terms of capital needs, for example, Vepco officers said total outlays for 1977 through 1979 now are estimated at $1.9 billion - of which $1.1 billion is planned for new generating plants.

But Vepco recently has experienced several very rough years that shattered its reputation as a Wall Street favorite. Customers have been shocked by rate increases, related to higher energy costs, that have been among the highest in the nation.

Even more critical, perhaps, Vepco has become embroiled in bitter disputes over construction of nuclear power plants. Vepco has been subjected to three government fines totaling $80,000, in five yers, based on nuclear construction errors.

And last month, the Nuclear Regulatory Commission staff raised "questions regarding Vepco commitment" to safe operations of its North Anna nuclear plant in Louisa County, the first unit of which Vepco has planned to start up this year and the output of which is considered vital to meet next summer's demands.

Vepco was slow to report two separate possible safety problems at the facility, and the NRC withheld, at least temporarily, an operating license it earlier had authorized. A hearing was held late in December, and Vepco now is waiting for a new decision on the license.

Customers of Vepco also have a big stake in the government decision because the utility will base a request for higher rates on initial use of the North Anna plant.

Moore said Vepco already has projected a deficiency in rates for the year ending June 30 of some $97 million - te amount of revenues below the rate of earnings permitted by the State Corporation Commission. In addition, costs associated with the North Anna plant are expected to bring the total Vepco rate increase request to more than $125 million.

Another rate increase request, of a substantila volume, is expected in 1978. But Moore said that, after Vepco cathces up with recent cost increases in the upcoming rate cases, its rate boosts should be more moderate - about level with general price inflation.

He readily admitted that Vepco made a mistake earlier in the 1970s by not requesting rate increases early enough in the wake of soaring oil prices.