The Electric ARM, the Jet-Mole and the Scorpion are emerging from the laboratory, and the result may be slower increases in the cost of electricity.

Those exotically named products were developed through research funded by the Electric Power Research Institute (EPRI), which calls itself the research and development arm of the nation's electric utilities. From its headquarters in Palo Alto, Calif., EPRI spends approximately $300 million a year to finance R&D and then licenses companies to manufacture the resulting products. EPRI's latest innovations include:

* The Electric ARM (Appliance Research Metering) system allows electric utilities to monitor inexpensively in the home rather than in the laboratory how various appliances are used and how much electricity they consume.

Previously, utilities had to rewire a home to connect each appliance to monitoring equipment. To use the Electric ARM, a utility plugs the appliance into a box the size of a standard electric timer and then plugs that box into an electric outlet. Electronic devices inside the box measure electricity use and transmit the information to equipment outside the house.

According to Alan Miller, vice president for marketing of Robinton Products Inc. of Sunnyvale, Calif., which developed the device with EPRI, "We had the concept, they EPRI had the concept, and it evolved jointly." The project represents how EPRI wants to work with private industry, according to Don Erickson, EPRI's manager for patents and licensing.

* The Jet-Mole, a cable follower, may allow utilities to cut the cost of replacing defective underground cables by as much as 90 percent, according to Erickson.

He explained that millions of miles of underground cable have been laid in the United States, often when the surrounding land was open. Now landscaping, streets and buildings have to be disturbed to replace cable under the standard procedure of digging a trench to expose it.

But the Jet-Mole can be planted through a hole dug to expose one end of the bad section of cable. It surrounds the cable and crawls along it for up to 300 feet, creating a tunnel around the cable. Once the defective section is cut at both ends, the tunnel permits workers to to pull out the section and insert a replacement.

The hydraulically powered device was developed with Flow Industries Inc. EPRI has applied for patents in connection with the Jet-Mole and obtained a trade mark on the name. The Jet-Mole will be commercially available by early to mid-1984.

* The Scorpion is EPRI's nickname for a cable plow that can lay underground cable much closer to obstacles than other equipment because it includes a plow boom that can swing full circle. Erickson said it is called the Scorpion because that's what it looks like.

Potomac Electric Power Co. has purchased a few Electric ARMS to evaluate, according to Miller, but this isn't the only instance of an area utility benefitting from EPRI's activities.

Charles Powell, Baltimore Gas & Electric Co.'s corporate director for research activities, said BG&E is using a lightning arrestor developed by EPRI on its power lines and that the utility is "interested in virtually everthing that's in the EPRI program.

Virginia Electric Power Co. spokesman Rodney Smith said his utility is using a number of items developed by EPRI, including new power poles that are somewhat taller than standard poles and have no crossarms, but can support larger lines that can transmit more electricty, reducing installation costs by up to $21,000 a mile.

EPRI was formed in 1972, partly in reaction to criticism that the electric utility industry didn't have its act together when it came to research, Erickson said. The utilities decided that they wanted an organization to identify research programs, contract them out and manage them. "We don't go out and say, 'Here's $1 million. We'd like you to look at acid rain,' " Erickson explained. "We specifically identify work that we want a contractor to perform and work out a budget."

Although most of the inventions it has patented are used directly by the electric utility industry, some may find their way directly to the consumer, such as an improved heat pump being developed with Carrier Corp.

EPRI thought the world would beat a path to its door for its better mousetraps, but no one did, so now it goes out to sell the results of its research to potential manufacturers, Erickson said. EPRI staffers attend trade shows, inform manufacturers of specific inventions in which they might be interested, and otherwise spread the word through the government's Patent Gazette, a private company's data base on technology, and its EPRI Journal.