The Senate is taking up a $100 billion tax bill designed to spur renewable energy investment, give tax breaks to businesses and individuals and protect more than 20 million people from the dreaded alternative minimum tax.

The package, which has bipartisan support, is one of the bills Congress must address before it adjourns for the year. It precedes debate this week on a $700 billion plan to bail out failing financial institutions.

The Senate moves first Tuesday on the alternative energy section of the package. It provides some $17 billion in incentives to develop and use wind, solar, biomass and other renewables.

It extends for eight years the investment credit for solar energy and the credit for homeowners buying solar heating equipment, at a cost of $3.2 billion. It establishes a new credit for plug-in electric drive vehicles, at a cost of $758 million.

A study commissioned by the Solar Energy Industries Association found that the eight-year extension would more than triple investment during that period, to $325 billion, and almost triple employment in the industry, to 440,000 in 2016.

The legislation would also adjust the alternative minimum tax to prevent more than 20 million people from seeing their taxes rise by an average $2,000. The AMT was enacted in 1969 to catch a very small number of rich people, but was never adjusted for inflation and must be fixed by Congress every year to keep its reach from spreading.

The cost of the AMT patch is more than $60 billion over 10 years. The bill also extends dozens of other targeted tax breaks that expired at the end of last year or are about to expire. The biggest is the $19 billion research and development tax credit. Also renewed are deductions for state and local general sales taxes, higher education costs and teachers' personal expenses.

The legislation additionally includes more than $8 billion in tax relief for Midwestern states hit by natural disasters this summer and for the more recent victims of hurricanes in Texas and Louisiana.

It requires private insurance plans that offer mental health benefits to offer benefits equivalent to those of medical-surgical treatments.

The bill must still go this week to the House, where there is strong recognition of the need to fix the AMT and solid support for the energy incentives and such tax breaks as the R&D credit.

But there is also a strong sentiment among many House Democrats that it is wrong to provide tax relief without parallel revenue increases to prevent further ballooning of the budget deficit.

The Senate bill offsets the energy tax breaks by tightening the rules by which oil and gas companies pay taxes on income earned overseas. It offsets about $25 billion of the approximately $68 billion in individual, business and disaster tax relief. There is no new revenue to pay for the AMT fix.