Energy Service Demands

TIAM comprises 42 energy-services in the five end-use sectors (see Table 1).

Table 1: Energy service demands in the TIAM model

Residential segments	Commercial segments	Industrial segments	Transportation segments	Other segments
Space heating	Commercial cooling	Chemicals	Domestic Aviation	Agriculture
Space cooling	Commercial cooking	Iron and steel	International Aviation	Non-energy uses in transport
Water heating	Commercial space heat	Pulp and Paper	Road Bus Demand
Lighting	Commercial hot water	Non-ferrous metals	Road Commercial Trucks Demand
Cooking	Commercial lighting	Non Metals	Road Three wheels Demand
Refrigeration	Commercial office equipment	Other Industries	Road Heavy Trucks Demand
Clothes washing	Commercial refrigeration	Industrial and Other Non Energy Uses	Road Light Vehicle Demand
Clothes drying		Other non-specified consumption	Road Medium Trucks Demand
Dish washing			Road Auto Demand
Electric appliances			Road Two Wheels Demand
Other energy uses			Rail-Freight
			Rail-Passengers
			Domestic Internal Navigation
			International Navigation

To fulfill each energy-service demand, a number of technologies exist. The technologies vary in terms of input fuel(s), efficiency and costs. In fact, each of the energy-services is treated as a function that consumes energy to satisfy the demand for a service (e.g., demand for auto transport, measured in billion vehicle kilometers). Similar to other bottom-up models, the energy-service demands in TIAM are projected exogenously. They are specified at the regional level based on a range of exogenously-given drivers such as GDP, GDP per capita, GDP per household and population. The energy-service demands are linked to the underlying drivers, using elasticity factors. The elasticity factors reflect the sensitivity of energy-service demands to a change in their underlying drivers. Usually, the assigned elasticities are less than one, highlighting that the energy-service demands grow slower than the underlying drivers. As the energy-service demands in the TIAM model are projected exogenously, they are independent to their prices. This means that the projection of an energy-service demand is fixed unless either the driver or the elasticity parameter changes. Therefore, although TIAM shows how the energy-service demands can be satisfied at the lowest possible cost, it is not able to reflect the ‘price effect’ which refers to the impact of a change in energy prices on the demand of energy services (Parkin et al., 2005). Hence, although the model provides a detailed technological representation of the energy system, it is not able to address the contribution of (price- dependent) energy-service demands in tackling climate change.

References

Babak Mousavi, “Analysis of the relative roles of supply-side and demand-side measures in tackling global climate change: Application of a hybrid energy system model,” vol. 2018.