credits are covering your initial tax liability for the year. This means, unless something changes in the near future (more taxable income or less child tax credit), you're not going to see a benefit from the solar credit. Again, you can carry it forward, but the residential credit is set to expire next year. I'm not sure anyone knows how a credit will be claimed in 2022 as it may be removed from the forms, assuming the credit isn't extended by Congress.