@DM7777 Thank you. I have reviewed your tax return. The energy credit is non-refundable. That means, if you do not have any income tax, you will not be able to use the credit to obtain a refund. There is no income tax liability on your tax return. There is only self-employment tax, which is Medicare and Social Security tax, not income tax.
Here is some information you may find helpful: What Is the Difference Between a Refundable and a Nonrefundable Credit?
