SearchEmail UpdatesContact UsResidentsBusinessVisitorsGovernmentOffice of the always open

Stay Connected

tumblr  facebook  Twitter

Ask for Clean Heat

Ultra-Low Sulfur 2 Oil

NYC Clean Heat has transitioned into the NYC Retrofit Accelerator, New York City's new one-stop resource for energy and water efficiency. Learn more at

Ultra-Low Sulfur No. 2 Oil

Ultra-Low Sulfur No. 2 Oil (ULS 2) is the cleanest heating oil available and can be made even cleaner by blending it with renewable biodiesel. Biodiesel is primarily derived from waste vegetable oil and soybean oil, and is subject to a state tax credit that can save money.  The conversion process is nearly identical whether or not biodiesel is incorporated. 

Converting to ULS 2 oil (possibly mixed with biodiesel) typically involves less upfront investment than converting to natural gas. However, it is still important to plan ahead.  Follow the steps below and contact the NYC Retrofit Accelerator team with any questions you may have throughout the process. For more information on converting to ULS 2, click here to download a detailed step-by-step guide.

1.    Obtain Conversion Costs

Most burners that can burn No. 4 oil can also burn ULS 2 oil and biodiesel. Conversion costs for ULS 2 oil are minimal unless the building needs a new oil tank.  Obtain a cost proposal from a licensed heating system contractor, or work with a qualified engineer if more extensive work is required.

2.    Benefits of ULS 2 vs. No. 4 Oil

No. 4 oil is a mixture of No. 6 oil and ULS 2 oil.  Reduced maintenance and increased boiler efficiency associated with ULS 2 make the operating costs between ULS 2 and No. 4 oil closer than many may realize. 

Click here to learn more about the hidden costs of No. 4 oil and the benefits of ULS 2.

3.    Understand Operating Costs

Switching to ULS 2 oil and/or biodiesel will have a positive impact on your operating costs, especially when taking advantage of the biodiesel tax credit and when installing efficiency measures. Gather at least 12 months of fuel delivery records for your building to complete a fuel usage analysis to estimate future operating costs.

NYC Clean Heat has transitioned into the NYC Retrofit Accelerator, whose team of efficiency advisors can help you conduct a fuel usage comparison to estimate your future costs when using ULS 2 and/or biodiesel using our Heating Oil Comparison Calculator. Contact the NYC Retrofit Accelerator to get started.

Oil providers, energy service companies, and other organizations offer incentives such as discounted service contracts, group buying discounts, or other offers to encourage buildings to convert from No. 4 heating oil to ULS 2 oil with biodiesel. Please click here for more information.