Recent New York City law requires buildings burning No. 4 or No. 6 heating oil, or "heavy" oil, to switch to cleaner burning heating fuels. Buildings burning No. 6 oil will have to switch starting this July and those burning No. 4 will have to switch when they replace their burner or boiler but no later than 2030. Converting a building to a cleaner heating fuel is easier than you might think. Here are two buildings that switched to No. 2 oil and natural gas, respectively. Converting to No. 2 oil: A Manhattan coop that burned approximately 27,000 gallons of No. 6 oil during the winter of 2009/2010 burned almost 10% fewer gallons during the following winter after switching to No. 2 oil. This is despite the lower energy (BTU) content of No. 2 oil and despite the 2010/2011 winter being colder than the year before. Cleaner burning No. 2 oil improved the boiler heat transfer and resulted in fuel usage reduction. Converting to Natural Gas: A Brooklyn coop's gas conversion required only $39,000 in upfront investment. In February 2007 the 120-unit building completed the internal conversion and started heating with cleaner-burning natural gas. The conversion proved instrumental in protecting the building from rising oil costs; since the switch the building's heating bills have averaged $146,000 per year, but meeting the same heat demand with No. 6 oil would have cost around $190,000 at current prices. Connect to Clean Heat NYC Clean Heat is a free service that will help guide your building through the conversion process, assist with evaluating conversion options, find qualified contractors, assemble financing and coordinate with utilities and fuel providers. NYC Clean Heat can also help form a cluster with neighboring buildings to get a gas line at no cost/low cost. Contact NYC Clean Heat To learn more, dial 311 and ask for NYC Clean Heat. To reach the NYC Clean Heat technical director to discuss converting your building, call 212-656-9202 or [email protected]. Isabelle Silverman is an attorney at Environmental Defense Fund, New York, N.Y.