August 1, 2011.
The Federal Energy Management Program (FEMP) and the Environmental Energy Technology Division (EETD) at Lawrence Berkeley National Laboratory (LBNL) are conducting a research project that aims to update the current purchasing specification for energy-efficient commercial boilers. Data available on the internet was used to document the efficiencies, prices and other relevant data on commercial boilers. Boiler models were classified according to their fuel use (gas or oil) and if they produced hot water or steam. Boilers were ranked from highest to lowest thermal efficiency. Scatter plots were used to assess the ranges of efficiencies over a range of boiler capacities and the highest 25% in efficiency were highlighted. The results show that the gas-water and oil-water boiler types have higher thermal efficiencies than steam boilers. Steam boilers are available in larger capacities the boilers’ price versus output capacity plot shows that the prices for boilers with lower thermal efficiencies are lower than medium and higher efficiency boilers. Gas-water boiler category has higher thermal efficiencies is due to the higher number of condensing boiler types in it. Condensing boilers are more efficient because heat is captured from water vapor in the exhaust gases. Because the life-cycle cost and the number of manufacturers with qualifying products must be taken into account when recommending boilers for FEMP's performance requirements, further analysis will need to be conducted before a final recommendation is made.
Lawrence Berkeley National Laboratory (LBNL)
This material is based upon work supported by the S.D. Bechtel, Jr. Foundation and by the National Science Foundation under Grant No. 0952013. Any opinions, findings, and conclusions or recommendations expressed in this material are those of the authors and do not necessarily reflect the views of the S.D. Bechtel, Jr. Foundation or the National Science Foundation.