Section 168 of the internal revenue code contains a Modified Accelerated Cost Recovery System (MACRS) by which businesses can recover investments in solar, wind, and geothermal property through depreciation deductions. The MACRS establishes the time over which various types of property may be depreciated (3-50 years). The allowance for bonus depreciation has since been extended and modified several times since the original enactment, most recently in December 2015 by the Consolidated Appropriations Act Of 2015 . Equipment placed in service before January 1, 2018 can qualify for 50% bonus depreciation. Equipment placed in service during 2018 can qualify for 40% bonus depreciation. And equipment placed in service during 2019 can qualify for 30% bonus depreciation.