Many wind turbines are slated to come online in the United States in 2019 and 2020
The U.S. Energy Information Administration (EIA) expects that U.S. wind capacity additions in both 2019 and in 2020 will be near the annual record level of additions set in 2012. Wind capacity additions through June 2019 totaled 3.7 gigawatts (GW). According to projects reported to EIA through surveys and on EIA’s Preliminary Monthly Electric Generator Inventory, operators expect another 8.5 GW to come online by the end of this year, with an additional 14.3 GW by the end of 2020.
Changes in annual wind capacity additions in the United States are often related to changes in tax incentives. The U.S. production tax credit (PTC), which provides operators with a tax credit per kilowatthour of renewable electricity generated for the first 10 years a facility is in operation, was initially set to expire for all eligible technologies at the end of 2012 but was later retroactively renewed.
Developers that scheduled projects to be completed in time to qualify for the PTC drove the high level of annual capacity additions in 2012 (13.3 GW). Similarly, the legislated phaseout of the PTC extension for wind is largely driving the increase in annual wind capacity additions in 2019.
When renewed in 2013, the PTC provided a maximum tax credit for wind generation of 2.3 cents per kilowatthour (kWh) for the first 10 years of production. Under the PTC phaseout, the tax credit decreases by 20% per year from 2017 through 2019. Facilities that begin construction after the end of 2020 cannot claim the PTC.
Under the current PTC legislation, wind projects are eligible to receive the tax credit based on either the year the project begins operation or the year in which the project owner demonstrates that project construction has begun and they have spent 5% of the total capital cost for the project. The 5% threshold provision, known as safe harboring, enables wind developers to receive the PTC based on the credit available for that year if they complete construction in no more than four calendar years after the calendar year during which facility construction began.
More: https://www.eia.gov/todayinenergy/detail.php?id=41373
Source: U.S. Energy Information Administration, Preliminary Monthly Electric Generator Inventory
= new reply since forum marked as read
That's probably the reason I thought of posting this - he's not at all worried about the ill effects of polluted air or water, but he believes that windmills cause cancer! 
