National Oilheat Research Alliance says B20 blend just fine

In Virginia, research conducted by the National Oilheat Research Alliance (NORA) on blending ASTM D6751 biodiesel with both standard and low sulfur heating oil confirms that blends up to 20 percent biodiesel can be used in heating oil without incident. This research includes both lab testing and field results. A recent service organization survey conducted by NORA and Brookhaven National Laboratory observed that some 35,000 buildings are currently using Bioheat containing more than 5 percent biodiesel with no issues.