April 20, 1986

WHY does electricity consumption on Long Island keep climbing? The answer to that question, business and public officials say, holds enormous importance for the continued growth of the Island's economy, the future of the Long Island Lighting Company and its Shoreham nuclear power plant, and the life style of Island residents. All indications point to the Island's robust economy as being the major factor in the growing use of energy. Increasing numbers of new businesses and expansion by existing companies, both in space and the number of employees, play the biggest role. In addition, new residential customers, besides growing in number, are using double the average electricity of existing customers. One reason is the growing popularity of electric heat.

THE ghost of P. T. Barnum will help close out the state's celebration of its 350th birthday next Saturday - and the legendary huckster is a fitting symbol for both organizers and critics of the yearlong party. Barnum, the Bethel-born promoter who was one of the creators of the Ringling Brothers and Barnum & Bailey Circus, is one of many Connecticut historical characters whom professional actors will portray during a ''Day of Living History'' at the Old State House in Hartford, the last of a series of events since the celebration began last May. To organizers of the celebration, the events have succeeded in the Barnum tradition, stirring excitement by giving people a good time before hitting them over the head with history lessons. To some historians and leaders of quieter towns, the concern with history has taken a back seat to the circus atmosphere of balloons, cow-chip-throwing contests and loosely regulated searches for ''hometown heroes'' and the oldest homes in town.

Bias against women in the New York State court system is so pervasive that ''they are often denied equal justice,'' according to a report by a special state task force that studied the courts for almost two years. The 23-member panel - set up in May 1984 by Lawrence H. Cooke, then the state's Chief Judge - concluded that female lawyers were ''routinely'' demeaned and treated patronizingly by male judges and attorneys. And it found that the credibility of female witnesses was sometimes questioned because women were viewed by some judges as emotional and untrustworthy. Calling the situation grave, the panel said some judges did not understand the nature of family violence and blamed the victims for it.

My work is a combination of film, music, electronics, storytelling, dancing, social commentary, impersonation, animation and anything else I come up with. What I do has been described as ''high-tech opera,'' ''live art,'' ''electronic stand-up comedy,'' ''avant-rock'' and that clumsy label ''performance art,'' which has always sounded to me like a bad translation from German. Fortunately, nobody knows what ''performance art'' refers to. This frees artists to experiment outside the traditions of dance, theater, music and narrative and still be included in festivals. It was two years ago here in Tokyo that I decided to try to film the concert we were presenting. Now I'm in town again and the film is finished, and I'm trying to get some distance on it. I'm beginning to see why Hemingway, Twain and Melville took to the water; to get away, to get a better look, to get some perspective. Even Francis Scott Key did his best work offshore. What other country can claim that its national anthem ends with a question? ''Home of the Brave,'' which opens Friday at the 57th Street Playhouse, begins with a projected animation of products falling from the sky. The performers ambulate on as anonymous clones wearing identical masks. Flintstone Kabuki crossbred with the Bauhaus. A drum machine bangs out an odd time signature. The central character lurches forward playing wolf howl double stops on an industrial remnant of a violin.

Broad Brush, a frequent winner against mediocre horses, took advantage of some top horses having a bad day to score a major upset victory in the $297,500 Wood Memorial at Aqueduct yesterday. The unheralded Maryland-based colt scored by half a length over Mogambo, with Groovy a neck behind in third place and Tasso, the 4-to-5 favorite, 1 1/4 lengths farther back in fourth. The winner, who paid $16 for $2 to win, ran the slow time of 1:50 3/5 for a mile and a eighth, including a final furlong in an extremely poor 0:14 2/5. Although the first four finishers are all considered likely to make their next starts in the Kentucky Derby on May 3, the outcome of New York's major prep race only strengthened the heavy Derby favoritism of Snow Chief and Badger Land, two California-based colts. Mogambo and Tasso, however, are both far more talented than they showed yesterday, and either could rebound strongly in the Derby. Both were victimized by a slow pace and a speed-favoring track surface yesterday.