# Residential

The household sector is described on the basis of 11 energy services   which include residential cooling, space heating and residential lighting and the units for all the services are in PJ. For the energy services "Residential Cooling" (RC), "Residential Space Heat" (RH), "Residential Cooking" (RK) and "Residential Lighting" (RL), the codes 1-4 are assigned to differentiate between sub-regions, for example, to differentiate between urban and rural regions. Apart from exceptions such as the USA or Canada, most geographical regions are only divided into the two sub-regions "rural" and "urban" - if no sub-regions exist, the codes for region 1 are selected by default. The projection of demand for energy services up to the year 2100 is carried out using suitable [drivers and elasticities](../regional_coverage/demand-projection.md).

Table 1: Energy service demands in the residential sector.
| Code | Energy service demand | Unit | Driver  |
|------|-----------------------|------|---------| 
| RH   | Space heating         | PJ   | HOU     |
| RC   | Space cooling         | PJ   | GDPPHOU |
| RHW  | Water heating         | PJ   | POP     |
| RL   | Lighting              | PJ   | GDPP    |
| RK   | Cooking               | PJ   | POP     |
| RRF  | Refrigeration         | PJ   | GDPPHOU |
| RCW  | Clothes washing       | PJ   | GDPPHOU |
| RCD  | Clothes drying        | PJ   | GDPPHOU |
| RDW  | Dish washing          | PJ   | GDPPHOU |
| REA  | Electric appliances   | PJ   | GDPPHOU |
| ROT  | Other energy uses     | PJ   | GDPPHOU |


The templates for the base year 2018 show the existing technologies that are modeled for final consumption in the household sector - investments in these technologies are not further possible. The template also includes the emissions generated by the household sector. Due to technological developments, there are possibilities to invest in new energy efficient technologies (with less emissions) in the residential sector. In ETSAP-TIAM, the technologies that could be used in the future are recorded and modeled in the templates for new technologies "SubRes_B-NewTech".  There is a large number of new technologies for the private household sector that will gradually replace existing technologies when they have reached the end of their assumed technological life. The new technologies are characterized and compared with each other based on factors such as the efficiency achieved, the annual utilization factor, the operating costs incurred, the service life and coefficients for seasonal factors. Region-specific hurdle rates are used to represent the investment costs to be incurred for new technologies in the residential sector by means of annuities.
The calibration of final energy consumption by energy source for the base year 2015 was carried out using the IEA's extended energy balance. Due to the lack of data from the IEA and other databases, expert judgments were used to determine the breakdown of energy consumption by energy services in demand.