solar Tax credit

Hi there,

  I am planning to get solar panels on my roof and I have heard that based on the total price of the process I can get a solar energy tax credit.  So does that mean I get the credit only if I own money at the end of the year to the federal govt? If I do not own any money or I get a refund back I won't be getting anything from the credit? Is my understanding correct?

 

Thanks