Vermont

Vermont's sales tax exemption for renewable-energy systems, originally enacted as part of the Miscellaneous Tax Reduction Act of 1999 (H. 0548), initially applied only to net-metered systems. The exemption now generally applies to systems up to 250 kilowatts (kW) in capacity that generate electricity using eligible "renewable energy" resources (as defined under 30 V.S.A. § 8002), to micro-combined heat and power (CHP) systems up to 20 kW, and to solar water-heating systems. The exemption is available for grid-tied systems and off-grid systems alike. Vermont's sales tax rate is 6%.  
 
"Renewable energy" is defined under 30 V.S.A. § 8002 as "energy produced using a technology that relies on a resource that is being consumed at a harvest rate at or below its natural regeneration rate." Biogas from sewage-treatment plants and landfills, and anaerobic digestion of agricultural products, byproducts and wastes are explicitly included. (The term "renewable energy" explicitly excludes solid waste that is not agricultural or silvicultural, as well as nuclear fuel, coal, oil, propane and natural gas.)