The celebration of Sun Day drew to downtown Washington yesterday a disparate blend of people, a few interested in putting down cash on solar hardware and many others attracted to solar energy as a corollary to saving whales, smoking pot, ending the Vietnam war and dancing to flute music.

Carroll Smith, his wife Dee and their 13-year-old daughter Winnie (who skipped school because her father said Sun Day was worth it) said they showed up at the Lincoln Memorial before dawn . They stayed all day looking at solar equipment - including a cardboard and tinfoil hot dog cooker - because they are moving soon to a solar-powered house.

Smith is an independent insurance agent from Springfield, who reads Mother Earth News for soar stories and is sick of utility bills.

"When you get those gas and utility bills in Springfield, you get the feeling that you'll never be very self-sufficient or secure," Smith said.

The insurance agent said these words just after the sun rose at 6:08 a.m. and shot a yellow flame across the reflecting pool behind the Lincoln Memorial. A few minutes later, a man with a guitar and a loud public address system added new lyrics to an old Woody Guthrie song: "This land is not corporation land, but you and I land . . . "

That first crowd of the day, about 500 people, had gathered for the dawn and sang along and danced in circles as they warned in the ascending sun. "Sure are a lot of different types of people here," Smith observed accurately.

There was a young woman from Kittery Point, Maine, named, appropriately, Joyce Sun. She wore a blanket of Indian design and said she was in town "working on whales, seals and native peoples rights."

When members of the crowd were asked if they had anything to say about Sun Day, Sun grabbed the microphone and led a few cooperative people in a Hopi Indian chant.

There also was an older man with an accordion, two daffodils and a propensity for singing. He introduced himself to many onlookers.

"My name is Carlos Van Leer and I'm a 71-year-old church activist. I went on hikes with retired Supreme Court) Justice William O Douglas. I've been described as an outgoing fellow if there ever was one."

Van Leer sang, played his accordion and danced. He composed a sun ditty, part of which went like this: "As welcome as solar ideas in the spring, tra la."

And there were others, including Beth Ellen Neff, a senior from Montgomery Blair High School, who painted yellow suns on her cheeks; Coletta Kemper, a Common Cause employe, who kept relighting candles before dawn so that she and her friends could see to eat their quiche; and several children who kept asking why they had to get up so early and why they couldn't go home.

At dawn, people near the Lincoln Memorial said they showed up because they thought solar energy was a good thing and the sunrise would be something to remember. At 2 p.m., when several thousand high school-age people packed the grounds near the Washington Monument, teen-agers said they thought Jackson Brown (a rock group that played in the afternoon) was an excellent band and solar energy seemed to be a good idea.

Between the sunrise ceremony, when ecologist Barry Commoner called President Carter's energy plan "chaos," and the afternoon music and speeches, when Russell Peters of the Office of Technology Assessments said that "without the sun, there would be no day at all - only nights," Carroll Smith and his family checked out more solar equipment.

"We've decided," said Smith wife, "that we've got to go out and build a solar house ourselves." To that end, Smith looked at Solar water heaters, ovens, fruit dryers, water pumps, home heating systems and wind mills.

One windmill, manufactured by the North Wind Power Company, is capable of supplying half the electrical needs for a family of four as long as the wind blows at 10 miles an hour, a salesman said. The windmill, installed, costs between $6,000 and $10,000.

One solar water heater, capable of supplying 60 percent to 70 percent of the water heating needs of a family of four, costs $1,349, installed. The solar fruit dryer, sold by the daughter of a Hungarian countess who invented it, costs $19.95, unassembled.

Smith said the high prices of the solar equipment, excepting the fruit dryer, forced him to plan to build his own.

In the afternoon's speech-making which many of the sun-worshipping young people seemed to ignore, Sen. Charles Percy (R-Ill.) said, "You have been here at the birth of an idea who's time has come." James Dickey, the poet, said, "The sun is all things to all men - (it) tells us where we are and where we ain't."

Annika Moyle, 15, of Walt Whitman High in Bethesda, said, "My mom called up the school and learned it was okay for me to come here as long as I bring a note to school tomorrow."