Milwaukee ? Saying the nation is on the verge of technological breakthroughs that would “startle” most Americans, President Bush on Monday outlined his energy proposals to help wean the country off foreign oil.

Less than half the crude oil used by refineries is produced in the United States, while 60 percent comes from foreign nations, Bush said during the first stop on a two-day trip to talk about energy.

Some of these foreign suppliers have “unstable” governments that have fundamental differences with America, he said.

“It creates a national security issue and we’re held hostage for energy by foreign nations that may not like us,” Bush said.

Bush is focusing on energy at a time when Americans are paying high power bills to heat their homes this winter and have only recently seen a decrease in gasoline prices.

One of Bush’s proposals would expand research into smaller, longer-lasting batteries for electric-gas hybrid cars, including plug-ins. He highlighted that initiative with a visit Monday to the battery center at Milwaukee-based auto-parts supplier Johnson Controls Inc.

During his trip, Bush is also focusing on a proposal to increase investment in development of clean electric power sources, and proposals to speed the development of biofuels such as “cellulosic” ethanol made from wood chips or sawgrass.

President Bush pretends to adjust his safety glasses during his tour of the Johnson Control Battery Technology Center, Monday, Feb. 20, 2006, in Glendale, Wis.

Energy conservation groups and environmentalists say they’re pleased that the president, a former oil man in Texas, is stressing alternative sources of energy, but they contend his proposals don’t go far enough.

They say the administration must consider greater fuel-efficiency standards for cars, and some economists believe it’s best to increase the gas tax to force consumers to change their driving habits.

Today, Bush plans to visit the Energy Department’s National Renewable Energy Laboratory in Golden, Colo., to talk about speeding the development of biofuels.