Two Midwest companies that are major players in the energy-control equipment industry are pushing innovative ideas to slash fuel bills for the nation's biggest energy user - the U.S. government.

Along the way, that goal could mean more business for both companies, Johnson Controls Inc. of Milwaukee and Honeywell Inc. of Minneapolis. Both are makers of automated systems to monitor and control energy use in large buildings.However, company officials said the measures they seek are not specific to their own companies but also would help competitors, plus suppliers of heating and air conditioning equipment.

The measures also would help the taxpayers who foot the bill for enormous energy waste at federal facilities, the companies point out. At stake: savings of $1 billion to $2 billion yearly from the government's fuel bills, which reached nearly $10 billion in 1990.

Last week Rep. Michael Synar, D-Okla., who chairs an energy subcommittee of the House Operations Committee, introduced a bill to create a federal ''energy bank."

It would have federal agencies contribute a percentage of fuel bills for five years to launch the bank, which would lend to energy-cutting projects like the control equipment, with loans repaid by fuel cost savings.

Five Wisconsin congressmen signed on as co-sponsors of the bill, which had been sought by Johnson Controls, said Douglas Decker, the company's business development director.

Meanwhile, Honeywell pursued a plan to put the government into ''performance contracts," said Glen Skovholt, Honeywell's director of governmental affairs policy and strategy.

They would allow a provider of energy control systems to borrow from a

financial institution for each project, with the government repaying the loan

from guaranteed fuel cost savings.

Mr. Skovholt said Honeywell has used these contracts to put equipment in ''over 750 school districts around the country," but that "the federal government is far behind everyone else in this country in getting with it."

Honeywell did not get the plan into last week's House Energy and Commerce Committee drafting of energy legislation, but Mr. Skovholt said it may be introduced separately in the House, as the energy-bank bill was, and that it is already in a Senate bill that could bring it to a House-Senate negotiating conference.

A House aide familiar with both companies' ideas said they complement each other and should spur hefty savings by the federal government, which is "not only the biggest energy user but the biggest energy waster" in this country.

A recent federal study of its buildings said the government could save up to $1 billion in fuel bills each year by using conservation technology.

President Bush last year ordered agencies to cut fuel use 20 percent by the year 2000, but he did not include a funding method.

The aide said an executive order under President Carter sharply cut federal energy use in the 1970s, but usage rose somewhat under President Reagan.