First, make sure you've entered the cost of the solar panels in the Home Energy Credits section. Enter it on the screen titled "Enter any additional energy-efficient improvements" on the line "solar electric costs." This credit is limited to your income tax liability, so if you don't owe any income taxes because your exemptions, standard or itemized deductions plus some other credits take your income tax liability to zero, you won't get a benefit from this credit. On a positive note, however, the solar panel credit carries forward and can be used to offset income tax liability in future years.
Turbo tax for the amount of income and tax due that I have entered so far assures me I will get the entire amount of my withheld tax due me for 1918, I understand that if I am due more it will be credited to me on my next year 2019 tax liability. I have many more deductions for medical and taxes and interest not enter yet. If I do, will the greater amount of credit due me for my 27,900 paid for the solar be fully credited. If not, then is there any need to enter the medical and taxes and interest deductions?