Businesses may claim a tax credit of $0.03 per gallon of bio-heating oil containing at least 5% biodiesel that is purchased for space or water heating between 2008 and 2018. The credit is capped at $500 or the total tax liability and must be claimed electronically with supporting documentation from the Maryland Energy Administration. Sole proprietorships, corporations, and other entities may qualify for the non-refundable credit.