At a Glance: Different sustainable fuels that are used for commercial applications include liquid fuels (biodiesel, renewable diesel, bio-oils) and gaseous fuels (biomass, biomethane, hydrogen). In order to be used for an industrial burner, these fuels must meet technical compatibility, economic requirements, and supply chain considerations
Sustainable fuels are renewable or recycled energy sources that reduce environmental impact compared to conventional fossil fuels while providing reliable heat for commercial and industrial applications. As industries worldwide face mounting pressure to reduce carbon emissions and transition toward cleaner energy, sustainable fuels offer practical pathways to meet environmental goals without completely redesigning heating infrastructure.
The shift toward sustainable fuels is driven by multiple converging factors.
- Climate Change: Environmental concerns create urgency for reducing greenhouse gas emissions.
- Economic Considerations: Fossil fuel prices and rising carbon costs make renewable alternatives increasingly competitive.
- Regulatory Pressures: Government mandates and emissions standards require businesses to adopt renewable sources.
Sustainable fuels fall into three main categories: liquid biofuels derived from organic materials, renewable gases produced from waste or renewable energy, and solid biomass fuels from forestry and agricultural sources.
Understanding Sustainable Fuels for Commercial Applications
What Makes a Fuel “Sustainable”?
A fuel is considered sustainable when it originates from renewable or recycled source materials that can be replenished within human timescales rather than geological eras. Many of these renewable fuels can produce lower net carbon emissions compared to fossil fuels by recycling carbon already in the natural cycle. For commercial burners, sustainable fuels must be compatible with existing burner systems or require only reasonable modifications.
Key Considerations for Commercial Use
Businesses evaluating sustainable fuels must consider several practical factors.
- Energy Efficiency: This determines how much heat the fuel produces per unit, affecting operational costs and burner sizing.
- Availability: Supply chain reliability ensures consistent fuel access without disrupting operations.
- Cost: Comparing the cost of renewable fuels to conventional fuels influences the economic case for switching, though incentives and carbon pricing increasingly favor renewables.
- Equipment Compatibility: Modification requirements affect upfront investment needs.
- Regulatory Compliance: Available incentives can significantly improve the financial attractiveness of sustainable fuel adoption.
Liquid Sustainable Fuels
Biodiesel
Biodiesel is produced through a chemical process called transesterification that converts vegetable oils, animal fats, and used cooking oil into diesel-like fuel. B100 (Pure Biodiesel) and B20 (80% petroleum diesel, 20% biodiesel) are the most common concentrations. Feedstocks can include soybean oil, canola oil, tallow, and recycled restaurant grease.
Biodiesel properties closely resemble petroleum diesel, though with slightly higher viscosity and lower energy content than conventional diesel. The exact difference can depend on the blend. When temperatures drop, biodiesel can gel, which can make it harder to burn. Storage stability requires attention to prevent degradation over time.
- Benefits: Ability to serve as a drop-in replacement with minimal or no equipment modifications at lower blend levels, established supply chains through fuel distributors.
- Challenges: Need for upgraded fuel lines and seals for higher blends, cold weather management strategies, slightly reduced fuel economy due to lower energy density.
- Applications: Boilers, furnaces, and process heaters originally designed for diesel fuel. Fuel delivery and storage systems can accommodate biodiesel’s properties.
Renewable Diesel
Renewable diesel is produced through hydrotreatment of vegetable oils at high temperatures and pressures. This process creates a fuel chemically identical to petroleum diesel with superior properties compared to biodiesel. Renewable diesel features excellent cetane numbers, indicating clean combustion and outstanding cold-weather performance that surpasses both biodiesel and conventional diesel.
While this alternative fuel is generally drop-in compatible, compatibility can depend on site-specific factors. It is the ideal sustainable fuel for any diesel-fired commercial burner if budget and supply requirements are met.
- Benefits: Performance matching or exceeding petroleum diesel in all respects, compatibility with all diesel equipment without modifications, and superior operational characteristics.
- Challenges: Higher costs compared to both biodiesel and petroleum diesel, plus more limited availability as production capacity expands.
Bio-oils
Most bio-oils are produced through fast pyrolysis, which occurs when biomass is rapidly heated in oxygen-free environments to create liquid fuel through thermal decomposition. The resulting bio-oil has a significantly different chemical composition from petroleum oils.
Equipment modifications are typically required, including upgraded fuel systems, modified nozzles, and corrosion-resistant materials.
- Benefits: Utilizing waste biomass otherwise lacking value and maintaining liquid fuel handling infrastructure.
- Challenges: Corrosion management, storage instability limiting shelf life, limited commercial availability restricting widespread adoption.
- Applications: Industrial process heating where facilities can manage bio-oil’s unique requirements and implement necessary equipment modifications.
Renewable Propane (Bio-LPG)
Renewable propane is produced from renewable feedstocks, including vegetable oils and waste materials, through advanced processing. The remarkable aspect of renewable propane is that it’s chemically identical to conventional liquefied petroleum gas (LPG), and it is typically used as a drop-in fuel in existing propane systems.
- Benefits: Exceptionally clean burning characteristics, versatile applications across commercial sectors, and complete compatibility with existing propane systems.
- Challenges: Limited production volumes as the industry scales up and higher costs compared to conventional propane.
- Applications: Commercial cooking operations, space heating, various process heating needs where propane infrastructure already exists.
Gaseous Sustainable Fuels
Biogas and Biomethane (Renewable Natural Gas)
Biogas is produced through anaerobic digestion of organic waste materials. Source materials include agricultural waste from livestock operations, food waste from processing facilities and restaurants, sewage from wastewater treatment plants, and captured landfill gas.
Through purification and upgrading processes that remove impurities and concentrate methane content, biogas becomes biomethane, which is essentially renewable natural gas with energy content comparable to conventional natural gas.
Facilities with significant organic waste streams can generate biogas on-site, effectively converting waste disposal costs into energy assets. Biomethane can be injected into natural gas pipelines or used directly on-site.
- Benefits: Waste-to-energy conversion creates circular economy value, renewable natural gas substitution without equipment changes, potential revenue from waste that would otherwise require disposal.
- Challenges: Gas quality variability requiring monitoring and adjustment, plus purification infrastructure costs for upgrading to pipeline-quality gas.
- Applications: Boilers, furnaces, industrial process heaters, combined heat and power systems that simultaneously generate electricity and useful thermal energy.
Hydrogen
Hydrogen-based fuels can be produced through multiple methods with varying environmental profiles. Green hydrogen uses renewable electricity to split water through electrolysis, producing zero-carbon fuel. Blue hydrogen employs steam methane reforming with carbon capture to reduce emissions.
Combustion characteristics of hydrogen fuels usually have higher flame temperatures and different flame properties than natural gas. Small hydrogen blends may be possible in some systems, but allowable blend limits and required modifications vary by burner design, controls, and local standards.
- Benefits: Zero carbon emissions at the point of use with only water as a byproduct.
- Challenges: High production costs, complex storage and transportation requirements, burner modifications needed for high concentrations or pure hydrogen.
- Applications: High-temperature industrial processes, steam generation, and future-forward installations positioning for hydrogen economy transitions.
Syngas (Synthesis Gas)
Syngas is produced through the gasification of biomass or waste materials at high temperatures. Composition consists primarily of hydrogen and carbon monoxide with variable ratios. Syngas can be produced on-site from local biomass or waste materials, creating energy independence.
- Benefits: Utilizes diverse feedstocks from forestry residues to agricultural waste, local production possibilities reduce transportation needs.
- Challenges: Quality consistency requires robust combustion controls, lower energy content than natural gas.
- Applications: Industrial boilers, process heating, and facilities already operating gasification systems that integrate fuel production with thermal needs.
Solid Sustainable Fuels
Wood Pellets
Wood pellets are manufactured from compressed sawdust and wood waste products, creating standardized cylindrical pellets with consistent size and density.
- Benefits: Wide availability throughout forested regions, carbon neutrality, and established technology.
- Challenges: Uses specialized handling and storage systems, regular ash removal and disposal, larger physical footprints than liquid or gaseous fuel systems.
- Applications: Large-scale boilers for industrial facilities, district heating systems serving multiple buildings, and industrial steam generation.
Agricultural Residue Pellets
Agricultural residue pellets are made from crop residues like corn stalks, rice straw, and palm kernel shells.
- Benefits: Utilizing agricultural waste to create additional farm revenue, local availability reduces transportation distances.
- Challenges: Variable quality depending on harvest conditions and processing, higher ash content than wood pellets requiring more frequent cleaning, potential slagging from alkali metals in some agricultural residues
- Applications: Agricultural processing facilities that generate residues on-site, rural industrial operations located near agricultural production.
Torrefied Biomass
Torrefied biomass undergoes mild pyrolysis treatment that partially decomposes the material, creating improved energy density and water resistance compared to raw biomass.
- Benefits: Better storage stability resisting moisture and biological degradation, higher energy content per unit volume, improved grindability.
- Challenges: Additional production costs for the torrefaction process and limited commercial availability as the industry develops.
- Applications: Co-firing with coal in transitioning facilities and industrial boilers moving toward renewable alternative fuels.
Emerging and Alternative Sustainable Fuels
Synthetic Fuels (E-fuels)
Synthetic fuels or e-fuels are produced using renewable electricity to synthesize hydrocarbon fuels through power-to-liquid and power-to-gas technologies. These processes create fuels chemically identical to conventional petroleum products.
- Benefits: Potential carbon neutrality when using renewable energy sources and atmospheric carbon capture, drop-in compatibility with existing infrastructure.
- Challenges: High production costs, energy-intensive processes with efficiency losses, early-stage technology still scaling toward commercial viability.
Waste-Derived Fuels
Waste-derived fuels recover energy from materials otherwise destined for landfills. Refuse-derived fuel (RDF) processes municipal solid waste into combustible material. Tire-derived fuel (TDF) utilizes scrap tires.
- Benefits: Waste diversion from landfills reduces environmental impact, energy recovery from materials lacking recycling options.
- Challenges: Stringent emissions control requirements due to diverse combustion products, operational challenges from variable composition, complex regulatory environments governing waste combustion.
Fuel Selection Considerations for Commercial Burners
Selecting appropriate sustainable fuels requires evaluating multiple factors.
- Technical Compatibility: Burner design and modification requirements, fuel delivery and storage infrastructure needs, combustion control system capabilities, and emissions monitoring equipment.
- Economic Factors: Fuel costs, price stability over contract periods, operating and maintenance cost differences.
- Supply Chain: Regional fuel availability, storage requirements, fuel shelf life.
- Environmental Performance: Carbon emission reductions, compliance with low-carbon fuel standards, waste reduction, and air quality improvements.
Power Flame’s Commitment to Advancing Burner Technology
Sustainable fuels for commercial burners span three main categories: liquid biofuels like biodiesel and renewable diesel, gaseous alternatives like biomethane and hydrogen, and solid biomass fuels like wood and agricultural pellets. Each fuel type offers distinct advantages and challenges for commercial use. Sustainable fuels offer valuable potential for future commercial purposes by significantly reducing environmental impact while maintaining reliable, efficient operations.
At Power Flame, we are proud to be at the forefront of innovation in industrial burner equipment in the United States. Our selection of Commercial/Industrial, Low NOx, and Process Burners includes options to accommodate alternative fuels. Our burners are UL-listed for B20 (20% biodiesel, 80% petroleum diesel) operation, and we are committed to incorporating the latest technology in our cutting-edge products.
To learn more about Power Flame, Find a Representative near you or explore our hands-on burner combustion training courses at our Parsons, KS headquarters.