Fuel choice: Marginal fuel market shares of new consumer purchases (distinguished from replacements) are calculated using principles from consumer choice theory. The marginal fuel market share represents the proportion of specific fuels chosen (such as 50% electric, 25% natural gas, 25% oil) for a specific type of purchase. For example, when there is growth in the residential sector, new housing construction creates a need for new space heating purchases. The model projects new residential space heating fuel market shares based on relative costs across fuel options as well as non-price factors.

Policies can be developed to modify the reference case mix of fuels chosen. These types of policies include promoting a specific choice of fuel (such as promoting geothermal space heating, ethanol, biodiesel or electric vehicles, or encouraging the electrification of residential and commercial sectors). 


Note that the fuel market share calculations are determined only for new additions to capital stock (rather than to replacements due to retirements caused by wear-out at the end of their useful lifetime). By default, retired stock is replaced with a similar type of technology (of the same fuel source). However, if desired, the user is able to apply a switch that will allow for consumers to convert to alternative technology types at the end of a physical lifetime.