The latest high-tech credit card trick has paved the way for an unmanned gas station in Portland, Maine. By inserting a special card into an automatic terminal and punching in several identification numbers and an odometer reading, some Portland drivers now can:
* Fill their vehicle's gas tank 24 hours a day, 365 days a year.
* Get a receipt with a detailed analysis of the engine's fuel efficiency.
* Drive away and pay later.
The A. R. Wright Oil Company of Portland and the NCR Corporation say their joint development, the Wright Express, is the fuel station of the future. A. R. Wright claims its software program in NCR's 1830 terminal can pinpoint fuel theft in commercial fleets and misuse of company vehicles, monitor engine efficiency, prevent unauthorized use of the credit cards, save clerical time, and produce round-the-clock service. There is even a 24-hour ''help button'' connected to a speakerphone that customers can use to get advice on how to use the equipment.
Others are not so sure the unmanned, self-service gas stations are the answer.
''They are appearing, but I'm not particularly impressed with them,'' says Vic Rasheed, executive director of the Service Station Dealers of America in Washington, D.C. ''They are advantageous only to the owners, who get their money back faster.
''And no facility should be unattended,'' he says. ''Gasoline should not be handled like milk or soft drinks, where you put in your quarter and get a Coke. I'm surprised the state fire marshal permits it.''
Maine's state fire marshal, Don Bissit, says Maine fire chiefs have approached the issue very cautiously and on a case-by-case basis. Maine approved the automated fuel station after long discussions with A. R. Wright, Maine fire chiefs, and the company installing the equipment. Mr. Bissit says all safety components were carefully tested, approved by Underwriters Laboratories, and most of the fire chiefs agreed the flame sensors and extinguishers in each service island were ''state-of-the-art protection.''
He cites a recent example of a woman who drove off with the fuel nozzle still in her gas tank:
''The car yanked out the pump and the electrical short started a fire. The safety system blanketed the island with fire-retardant powder in seconds and had the fire out before the fire engines arrived.''
Chief Joseph McDonough, of the Portland Fire Department, says of the unmanned station: ''It would be easy to say no, no, no, because it's something different, but I don't think that's the best route. With lots of them around the country now, I'm hard pressed to say 'no, you can't do it here.' ''
''Experimental, unmanned gasoline stations have been around for several years ,'' says Jerry Schanke of the American Petroleum Institute in Washington, D.C. ''They've mostly been for commercial use - on farm cooperatives, for example, where farmers activate the system with a card - but not for the general consumer.''
Test markets using magnetic oil debit cards have also appeared at service stations in California and Illinois as well as at convenience stores around the country, and several major oil companies plan to install the systems later this year, according to Mary Lynn, a research analyst at International Data Corporation in Framingham, Mass.
''But there are really very few of these systems in general use now, it's so new to the marketplace,'' she says.
(Diebold Inc. introduced its Tabs Automated Fuel System May 17. A Diebold spokesman says the company hopes to have a test installation sometime in the next three months.)
Parker Poole III, A.R. Wright's executive vice-president, says he would like to take the system ''as far as possible'' in New England. He hopes to have five new Wright Express stations in the region by the end of the year serving commercial fleets and the general public.
Rasheed says he doubts the experimental stations are going to encourage mainstream gasoline sales.
''Their overall use will be limited; after-hours sales possibly, or in rural areas or along highways, but I don't foresee a sudden supplanting of service stations across the country.''