The energy burden of emergency medical services activities

Background: We have previously reported the greenhouse gas (GHG) emissions from emergency medical services (EMS) operations. independent of environmental concerns is the basic premise that GHG emissions arise from energy consumption, and energy is becoming increasingly scarce and expensive. Objective, The purpose of this post hoc analysis was to explore the energy burden of EMS activities by converting previously reported GHG emissions data into standard energy consumption measures, and by creating a preliminary estimate of the total energy consumption of EMS systems in the United States. Methods: The annual GHG emissions data previously reported by 10 North American EMS systems were converted into the standardized raw energy measures "thousand British Thermal Units" (kBTU) and mega-joules (MJ). Total energy consumption, per-response energy consumption, and percapita energy consumption were calculated, as were the relative contributions of each energy source. The per-response and per-capita measures were respectively multiplied by the estimated number of annual ambulance responses (21 million) and approximate population (309 million) of the United States to form a preliminary estimate of the total annual energy consumption for U.S. EMS systems. Results: The participating EMS systems consumed a total of 171,374,481 kBTU (180,809,674 MJ) of energy to provide 409,446 EMS responses to a population of 4.9 million. This translates into 418.6 kBTU (441.7 MJ) per response and 34.8 kBTU (36.7 Mj) per resident. Diesel fuel and gasoline accounted for 79.5% of energy consumption, followed by natural gas (13.3%) and electricity (7.2%). Extrapolating these figures to the response and population estimates for the United States indicates that EMS in that nation consumes approximately 8.8 to 10.8 billion kBTU (9.3 to 11.3 billion MJ) of energy each year. Conclusion: North American EMS systems consume• considerable energy, with U.S. systems consuming an estimated 8.8 to 10.8 billion kBTU (9.3 to 11.3 billion MJ) of energy each year. Diesel fuel and gasoline are the primary energy burdens for EMS systems, but natural gas and electricity combined represent approximately 20% of EMS-related energy consumption. Changes in either the price or supply of any of these energy sources could have a measurable impact on EMS operations