I am a resident of California, however I have a 2nd home in Hawaii. I just installed renewable energy solar panels on my Hawaii home. How do I get a refund for these new panels? (I want a "refund", not a credit).
What you want doesn't matter here. If you want a refund, ask the installer for that refund. If you want a credit, and you qualify for it, then you apply for it via your tax return. Now understand the difference between a credit and a deduction. Generally, the credit is better.
Deduction - this subtracts from your taxable income. By lowering the amount of income you are taxed on, that reduces your taxes accordingly.
Credit - This is subtracted from your tax liability directly. So if your tax liability is $1000 and you have a $500 tax credit, that reduces your taxes directly by $500, regardless of the taxable income.