The tax credit for the following items can be carried forward from the 2018 tax return to future years:
- Solar panels
- Solar powered hot water heaters
- Wind turbines
- Geothermal heat-pumps
- Fuel cells
If you have a carryover from 2017, you may claim the amount on the 2018 return and carryforward any unused amount to the following year.
The energy efficiency tax credit is technically "non-refundable" which means at the end of the year, you can't get back more in credits than you paid to the government in taxes throughout the year. If you are unable to claim the entire 30% of your purchase for the above products in one year, you can carry forward the unclaimed portion to future years. The IRS has not determined how long the tax credit can be carried forward.