Aug. 25, 2011: Condensing Hydronic Boiler Offers Renewable Fuel Options
The company said the Vantage boiler, which has been available since 2003 as an ultra-high-efficiency condensing hydronic boiler, now has the capability to use B100 biodiesel and ultra-low sulfur (under 15 ppm) heating oils for full condensing operation.
“As a result of comprehensive testing at the independent Brookhaven National Laboratory, it has been proven that the Vantage can meet or exceed the thermal efficiencies attainable with natural gas,” said Erin Sperry, Fulton’s commercial heating product manager. “We’re diligently exploring renewable energy resources and developing relevant product technologies.”
The Vantage has been available for dual-fuel operation: natural gas and #2 heating oil during gas supply interruptions. However, previous system controls prohibited the boiler from operating in condensing mode during oil-fired operation.
The nearly sulfur-free characteristics of B100 biodiesel and ultra-low-sulfur heating oil have allowed for new developments. The biodiesels used in the Brookhaven testing facility included biodiesels produced from both soybeans and recycled tallow.
Test findings indicated:
• Ignition on B100 biodiesel, even from cold start, was identical to that observed with traditional #2 heating oil.
• Carbon monoxide emissions and smoke-number readings were essentially maintained at zero during steady-state operation and normal excess air level of 25 percent.
• Following test runs, burner head inspections found no significant coke deposits.
• Measurable reductions for NOx, SO2, and soot were observed.
• Predicted corrosion rates were in the acceptable range for the application.
• Boiler jacket loss, which was monitored using the standards of the American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE) Standard 103, was found to be 0.2 percent of steady state input, a very low value.
At Brookhaven, boiler efficiency was measured using both an indirect flue-loss method and a direct input/output method. As typically observed with hydronic boilers, efficiency and condensate collection rate are impacted by the return-water temperature. At high fire with a return water temperature of 122°F, the efficiency was found to be 88 percent. At low fire with a return-water temperature of 90°, the efficiency was 93 percent. Under BTS-2000 test conditions of 80° return-water temperature and 180° supply water temperature, the rated efficiency was 98 percent at high fire.
The B100 biodiesel Vantage boiler is commercially available up to 4 million Btuh, and is capable of configurations for liquid fuel, natural gas, or dual-fuel operation.
Funding for testing was provided through the support of the New York State Energy Research and Development Authority (NYSERDA).
For additional information, visit www.fulton.com.
Publication date: 08/22/2011