An 18-month demonstration involving 121 properties and approximately 275,000 gallons of renewable fuel highlights the potential for biodiesel and renewable diesel to transform the home heating industry without requiring widespread equipment replacement.
The National Oilheat Research Alliance (NORA) has released findings from an extensive field study demonstrating that blends of biodiesel and renewable diesel can successfully replace conventional petroleum-based heating oil in a wide range of existing residential and light commercial heating systems.
Conducted over 18 months across Pennsylvania and Massachusetts, the study evaluated the performance of 100% renewable liquid heating fuels under real-world operating conditions. Researchers found that blends containing 50% renewable diesel and 50% biodiesel (RD50/B50), as well as 80% renewable diesel and 20% biodiesel (RD80/B20), could be used successfully in existing oil-fired heating equipment with few or no modifications.
The findings represent an important development for the delivered fuel industry, offering a potential pathway to reduce dependence on petroleum-based heating oil while maintaining much of the infrastructure, equipment, and distribution network already serving homes and businesses.
Real-World Testing Across 121 Properties
Unlike laboratory demonstrations conducted under controlled conditions, NORA’s field study was designed to evaluate renewable fuels in the types of heating systems consumers already own and operate.
The project included 121 residential and light commercial properties equipped with a variety of boilers, furnaces, and water heaters. Participating properties were divided into two groups to evaluate both detailed equipment performance and routine customer experiences.
At 28 locations, researchers conducted periodic inspections, combustion testing, and fuel sampling throughout the demonstration. The remaining 93 properties received fuel deliveries and routine service through participating heating oil providers, reflecting typical customer operations.
Importantly, researchers did not require fuel storage tanks to be replaced, emptied, or cleaned before the renewable fuels were introduced. Heating systems also remained largely unchanged, allowing researchers to assess the compatibility of renewable fuels with existing equipment and infrastructure.
Only four sites required upgrades to burner primary controls to accommodate differences in flame luminosity associated with the renewable fuel blends.
These conditions provided valuable insight into the practical challenges and opportunities associated with transitioning existing heating oil customers to renewable alternatives.
Industry Collaboration Supports Large-Scale Demonstration
The study brought together renewable fuel producers, equipment manufacturers, researchers, and heating oil distributors.
Clean Fuels Alliance America co-sponsored the project and provided supplemental funding, while Chevron supplied approximately 275,000 gallons of biodiesel and renewable diesel. Chevron also worked to maintain fuel pricing comparable to conventional heating oil and existing biodiesel blends during the demonstration.
Burner manufacturers R.W. Beckett Corporation and Carlin Combustion Technology provided technical expertise, while eight regional heating fuel providers supported deliveries, equipment servicing, and customer participation.
The collaboration demonstrated how existing fuel distribution networks and service providers can play a central role in introducing renewable liquid fuels to established heating markets.
Building on Decades of Cleaner Heating Fuel Innovation
The successful demonstration follows more than two decades of improvements in heating fuel quality and equipment compatibility.
Historically, conventional heating oil contained sulfur concentrations ranging from approximately 2,000 to 5,000 parts per million. The transition to ultra-low-sulfur heating oil, containing no more than 15 ppm sulfur, helped reduce sulfur-related emissions and equipment fouling while supporting cleaner combustion.
Biodiesel subsequently emerged as another opportunity to improve the environmental performance of liquid heating fuels.
The adoption of ASTM D6751 specifications for biodiesel in 2002, followed by the inclusion of biodiesel blends up to B5 in ASTM D396 in 2008, helped establish a foundation for broader use of biodiesel in heating applications.
Continued research, equipment development, and industry collaboration have supported the expansion of Bioheat® fuel, which incorporates biodiesel into conventional heating oil.
More recently, advancements in renewable diesel production and higher biodiesel blend compatibility have created opportunities to move beyond partially renewable heating fuels toward blends made entirely from renewable components.
A Potential Pathway for Lower-Carbon Home Heating
Biodiesel and renewable diesel are produced through different processes, but both can be manufactured from renewable feedstocks, including soybean oil, used cooking oil, and animal fats.
Renewable diesel is a hydrocarbon fuel with properties similar to petroleum diesel, while biodiesel is a fatty acid methyl ester fuel produced through transesterification.
Combining the two fuels offers an opportunity to leverage their complementary properties in heating applications.
The NORA demonstration suggests that renewable liquid fuels could offer heating oil customers an alternative to conventional petroleum products without necessarily requiring the costly replacement of otherwise functional boilers, furnaces, storage tanks, or fuel delivery systems.
This approach could be particularly relevant in regions where liquid heating fuels remain an important energy source and where existing homes may face practical or financial barriers to adopting alternative heating technologies.
However, broader commercialization will also depend on factors including fuel availability, pricing, applicable fuel specifications, manufacturer approvals, and continued evaluation of long-term equipment performance.
What’s Next for Renewable Liquid Heating Fuels?
NORA President Michael Devine presented the study’s findings during several industry conferences, including the Southern New England Energy Conference, Pennsylvania Petroleum Association Fall Conference, and Empire State Energy Conference.
The presentations highlighted the potential significance of the research for fuel distributors, equipment manufacturers, and policymakers evaluating pathways to reduce emissions from residential and commercial heating.
With 121 participating properties, approximately 275,000 gallons of renewable fuel supplied, and minimal equipment modifications reported, the demonstration provides meaningful field evidence supporting the technical feasibility of using biodiesel and renewable diesel blends as fully renewable liquid heating fuels.
For an industry built around reliable fuel delivery and long-lived heating equipment, the findings suggest that the transition to renewable fuels may not require abandoning the systems already in place.
Instead, the next chapter of liquid heating could involve changing the fuel itself.
Additional Findings: Maintenance, Fuel Quality, and Equipment Performance
Beyond demonstrating basic compatibility, the study provided insights into combustion performance, maintenance requirements, and fuel storage conditions.
According to a summary published by the Pennsylvania Petroleum Association on October 11, 2026, most participating systems maintained combustion performance within manufacturer specifications. Three sites required corrective measures, with no recurrence of the identified issues.
Researchers also found no meaningful increase in fuel-related maintenance among the 89 sites with sufficiently detailed service records. Although some locations experienced fuel-system issues, many were associated with existing equipment conditions or storage tank contamination rather than the renewable fuels themselves.
The study did identify areas requiring continued attention. Fuel stability declined at certain locations during summer storage, while water, sediment, and biological contamination remained important considerations. Researchers also observed greater burner-head deposits in some cold-chamber boilers, reinforcing the importance of routine professional maintenance. Pennsylvania Petroleum Association+1
These findings suggest that successful adoption will depend not only on fuel compatibility but also on the same sound storage, handling, and equipment maintenance practices that support reliable operation with conventional heating oil.
For fuel suppliers and heating equipment professionals, the study provides an encouraging technical foundation for expanding renewable fuel offerings while continuing to evaluate long-term performance and customer needs.