In a move sure to anger some parts of the scientific community and many members of Congress, the Carter administration plans to halt construction of a massive research project to produce fusion energy using laser light.

The $200 million project, known as Nova, was begun last year at the Lawrence Livermore Laboratory at the University of California, where it is being built to demonstrate that the world's most powerful laser can be used to generate the 100-million-degree heat needed to fuse atomic nuclei. Such fusion, if it can be begun and sustained, produces more energy than it consumes, and is potentially a limitless source of energy for mankind.

Sources inside the administration said the White House Office of Management and Budget has decided to cutt off funding for Nova in the coming fiscal year. The Department of Energy has asked OMB for $60 million for fiscal 1981 to continue construction, a request OMB denied last week after months of internal debate.

"Nova fell victim to the money crunch," said one source who asked not to be identified. "It just happened to be the most expensive item on the Energy Department's list of research projects."

Excavation of the land in Livermore, Calif., where Nova is to be built, has already been completed, a spokesman for the laboratory said yesterday, and concrete for its foundation is being poured. Congress had authorized $56 million in fiscal 1980 on Nova on top of $23 million it authorized in fiscal 1979.

The Livermore spokesman said it came as news to him that Nova will be scratched from next year's budget, declaring: "As far as we're concerned, we won't know if it's in or out until President Carter sends his next budget to Congress on Jan. 19."

Sources said there are two reasons OMB is calling a halt to Nova construction. One is to save money, the other to slow down the project so that many questions about how best to proceed with Nova can be answered.

"There are many scientists who thought Nova was moving too fast," said Bell Laboratories' Dr. Solomon Buchsbaum, an adviser on research to the Energy Department. He said he was unaware of the OMB decision to halt construction of Nova, but "while a halt may add to the cost of constructing Nova, it might turn out to be a good idea to slow things down."

Nova was planned as the fifth super-powerful laser at Lawrence Livermore. These devices generate enormous heat by striking pellets of hydrogen fuel with laser light. The first started up in 1974 and generated a light impulse of 400 billion watts. A year later its successor produced a 1-trillion-watt pulse and a year after that a third laser generated a pulse of 5 trillion watts.

Designed to produce a light pulse of 300 trillion watts, Nova was to be built alongside a laser at Livermore known as Shiva that is today the world's most powerful laser. Shiva, which generates a light pulse of 30 trillion watts, was fired for the first time in November of 1977 and has since been fired at a hydrogen fuel target 230 times.

Scientists say that Shiva has routinely created temperatures of 5 million degrees Centigrade in the laboratory, reaching 50 million degrees on at least 10 occasions. The Shiva laser has raised the temperature of hydrogen gas inside its target chamber to where the gas becomes so compressed it turns into a liquid 100 times heavier than water.

Nova was to be built in phases, the first consisting of a new target chamber to house the tiny pellets of hydrogen fuel and contain enormous temperatures reached when the fuel is struck by the laser light. It was also to have a new laser "gun" to achieve higher energies than had ever been reached before. This phase was to cost $136 million and was scheduled for completion in late 1982.

The next phase was to tie Nova with the existing Shiva laser and to replace the optics used in Shiva to concentrate the laser light with even more powerful mirrors and lenses. Phase two had no target date and still has none.

The building to house the Nova laser is to be 330 feet long and 210 feet wide. The bay where the laser is to be placed is 220 feet long, 56 feet wide and 50 feet high. The combined Nova and Shiva buildings were to be 550 feet long and 210 feet wide, which would make them the largest buildings of their kind anywhere in the world.

Fusion is described by many scientists as the answer to the energy crisis. The same process the sun uses to create heat and light, fusion requires temperatures from 50 million to 100 million degrees to be able to work.

One approach scientists in the United States have taken to create these temperatures is using multiple beams from high-powered lasers to heat a solid fuel pellet of hydrogen, deuterium and tritium. This vaporizes the pellet and triggers fusion reactions in the vaporized gas that allow the gas to get hotter and hotter.

The Livermore laboratory is believed by most scientists to be well ahead of any other laser fusion lab in the United States or anywhere else in the world in the attempt to reach fusion temperatures of 100 million degrees.

A second approach to fusion is the use of huge magnets to contain the 100-million-degree temperatures reached in the fusion reaction. Most of this work is going on at the Los Alamos Scientific Laboratory in New Mexico and at Princeton University, where a new magnetic confinement device is under construction.