Two Marylanders who used beer and soda cans to build solar heaters -- one for a large, $50,000 greenhouse near Wheaton and another for a $13 window unit -- were honored by the Department of Agriculture this week at the unveiling of the 1980 Yearbook of Agriculture.

Rick Scaffidi, a 24-year-old University of Maryland graduate, last spring built a commercial greenhouse on upper New Hampshire Avenue using thousands of black-painted cans on the back wall and 350 tons of river stone under the floor to hold the heat in winter and cool the 100-foot-long greenhouse in summer. Fans blow the heated air from the peak of the greenhouse through the rocks under the floor.

Scaffidi and a Penn State graduate student with whom he has designed other solar greenhouses have written one of the yearbook's two solar articles.

The 408-page, 1980 edition of the yearbook, the federal government's single most popular publication, is entitled "Cutting Energy Costs" and is devoted primarily to ways farmers and homeowners can save money by saving energy. The book has articles on how to use less energy in raising hogs and poultry and in growing timber and fruit trees, and articles on saving energy with landscaping, with household appliances and in preparing foods.

Several of the articles are written by Maryland residents, most of whom are associated with the University of Maryland or with the Agriculture Department and its research station in Beltsville.

Scaffidi, who has a cooperative research agreement with the Department of Agriculture to test the effectiveness of his new greenhouse, says in his yearbook article that "several years ago labor was the most costly (aspect of) growing greenhouse crops . . . now fuel costs have surpassed labor costs and attention has switched to reducing those fuel costs."

Since this is the first winter for his solar greenhouse, Scaffidi can only estimate how much his solar system will save in fuel costs.

"But I estimate I'll spend only about $300 for the whole winter when most greenhouses this size pay $1,000 a month in fuel oil bills and somewhat less if they have natural gas," he said.

The underground rock level did help during the summer, Scaffidi said, when greenhouse temperatures were always about 10 degrees cooler than outside.

The $13 window solar unit of 13-year-old Patrick Platt III, of White Hall, also is relatively untried. He built it this spring and it has been in shows and fairs ever since, winning a first prize at Maryland's state fair.

"We just tried it out a little while ago and it's pretty good," said Platt, a Harford County eighth grader. "The temperature gets up to 140 degrees inside the box, where the Coke cans and everything are painted black (and are warmed by the sun). A fan blows air from the room into the bottom of the box and the hot air comes out the top."

Platt said he drank all the Cokes that went into his solar system. But Scaffidi admitted, "We didn't drink all the beer and sodas; there's thousands of cans there." He added, "We bought them at the Alcoa aluminum recycling plant for 15 cents a pound. The stones didn't cost much, either -- $6 a ton."

The entire greenhouse cost more than Scaffidi had estimated, largely because Montgomery County required him to spend $25,000 to improve New Hampshire Avenue in front of the building.

Major attractions at this week's reception to introduce the yearbook were two Turkish Akbash sheepdog puppies who licked the face of Agriculture Secretary Bob Bergland and were hailed as the sheep farmer's dream dogs.

The Akbash dogs, large, white and as woolly as the sheep they are bred to protect, were imported into this country in 1978 by David and Judith Nelson, a State Department official, and his wife, a molecular biologist, who live in Bethesda.

David Nelson said there are now 44 Akbash in this country, including several the agriculture department is now testing with government herds of sheep.

"Many breeds of sheep dogs, bred for herding, turn against sheep," Nelson said. "But these dogs live with the sheep and are very placid, except when the sheep are endangered. They should be very good against coyotes and wild dogs since poisons have now been outlawed and people are looking for alternatives."

The Nelsons and their three children keep most of the eight Akbash they own and breed at a kennel in Clinton.

While no breed of sheep dog is mentioned in the yearbook, one article on "How to Raise Sheep Easier and Cheaper" does note that "more and more, sheep farmers are getting working sheep dogs."

At $9.50, the 1980 Yearbook is bigger, more informative and more than twice as expensive as the 1979 version, a $4.50 paperback called "What's to Eat." The '79 book was done in a children's comic format and aimed in large part at urban and suburban residents rather than at farmers. The 1980 yearbook has more articles that will interest farmers and gardeners, according to editor Jack Hayes.

While the agriculture yearbooks have been issued since the mid-1800s, those issued since 1936 have focused on a different subject each year and have become widely popular as reference books. The 1965 Yearbook is still the all-time best-seller, having been reprinted by the Government Printing Office (GPO) and as a paperback by two private publishers.

Congress gets more than 230,000 copies of every yearbook, 400 for each representative and 550 for each senator, which members give for free to constituents who request them. They can be purchased at GPO bookstores, as can yearbooks from as far back as 1948, or ordered by writing the Superintendent of Documents, U.S. Government Printing Office, Washington D.C. 20402.