State law exempts renewable systems from sales tax

Wisconsin law exempts wind, solar, and anaerobic digester systems from the sales and use tax, effective July 2009.

In order to be considered an eligible product, devices must be capable of producing at least 200 watts of alternating current or 600 British thermal units per day. The exemption under does not apply to uninterruptible power sources that are designed primarily for computers.

The law also exempts "receipts from the sale of and the storage, use, or other consumption of electricity or energy" produced by a qualifying system.