furthermore the capital grants for wind power plants provided under the latter act of can explain partly the permanent growth in wind electricity capacity since then the ptc was created along with itc and provides an inflationadjusted tax credit of usd mwh inflationadjusted for electricity genherated from qualifying renewable energy projects in particular wind indeed the most rapid growth did not happen until after while the ptc could have played a key role in the business case for new renewable power plants there were intermittent interruptions of the ptc which occurred when congress delayed in reauthorising the act