The Senate yesterday began a fight over two rival energy bills, one involving a fairly heavy commitment to develop synthetic fuels as the Carter administration has proposed, the other more skeptical as to synfuels and inclined to put money instead into weatherization, solar energy and gasohol.

The one bill from the Senate Energy Committee would spend $20 billion on synfuels and create a government owned public synthetic fuels corporation (formerly called the energy security corporation) the administration wants. The other from the banking Committee would spend a more modest $3 billion to $10 billion on synfuels while spending $11 billion on conservation, solar power and gasohol.

While President Carter and Energy Secretary Charles Duncan were defending creation of the synthetic fuels corporation, President Carter's Democratic rival, Sen. Edward Kennedy (d:-Mass.) took to the Senate floor to urge Carter to reimpose price controls on fuel oil and crude oil.

Kennedy, over the weekend, had urged the president to threaten to veto the "winfall profits" tax bill if it did not recover more profits from the oil companies than the Senate Finance Committee has proposed.

Kennedy said yesterday that Organization of Petroleum Exporting Countries' price increases account for less than half of the increased cost of oil in the United States, and he called on Carter to "roll back oil prices" by suspending decontrol or reimposing controls on such products as fuel oil.

Kennedy said Carter could not ask for restraint on the part of the general public "while oil companies reap huge profits."

Kennedy, who favors a conservation approach, has had a much-scaled down version of his bill to provide grants and loans to everyone for weatherization adopted as part of the Energy Committee bill now on the floor. w

Sen. William Proxmire (D-Wis.), chairman of the Banking Committee, said yesterday the "most important differences" between his bill and the Energy Committee approach are "the roles provided for the federal government" and the degree of commitment and cost.

The Energy Committee bill has the government involved "up to their eyeballs," Proxmire said, and would "result in very, very serious inflation."

But Energy Committee Chairman Henry M. Jackson (D-Wash.) said the country is "dangerously dependent on foreign oil imports," and needs a large national commitment to "rid itself of the bondage imposed by OPEC, the economic bondage, the increasing threat to our national security."

Energy Secretary Charles Duncan, in a letter to Senate Majority Leader Robert Byrd (D-W.Va.), said a corporation is necessary "to bring aggressive and expert management and business principles to bear on all aspects of the program." Duncan called the Banking Committee a "business-as-usual" approach.

The Banking Committee version is supported by a coalition of oil interests, business and environmentalists, who feel a large synfuel program is technologically questionable, threatens the environment, and -- most important to big business and oil interests -- would bring government into energy production.

The Energy Committee version would give loan and price guarantees, but also provide for government-operated facilities if all other stimuli fail to produce enough new plants.

The Banking version would set up no new agency and provide only loan and price guarantees to six coal and six oil shale plants.

Sources expect the vote to be close. Yesterday, the Banking version picked up the support of powerful Majority Whip Alan Cranston (D-Calif.). p

Work on the bill is expected to take all week, with the first key votes coming tomorrow.