combustion equivalent

com·bus·tion e·quiv·a·lent

the heat value of a gram of carbohydrate or fat oxidized outside the body.
References in periodicals archive ?
A price tag of pounds 97,500 on a vehicle indicates a fair chance that it is not going to be the internal combustion equivalent of a hair shirt.
All-Electric Production Vehicle Breaks Barrier; Achieves Four-Times Fuel Efficiency of Internal Combustion Equivalent