To achieve 1.5°C targets, it has been reported that it is necessary to reduce the net-CO₂ emission to zero. The most feasible zero-emissions scenario is the scenario that minimizes the energy demand to the lowest amount and not depends on the negative emission technology like Carbon Capture and Storage (CCS). However, it is not realistic to simply reducing energy demand by drastically improving efficiency of appliances or reducing the number of appliances to zero. It is necessary to express the change in efficiency in appliance stock by taking into account the time required for the dissemination of measures appropriately. In addition, reducing the number of appliances changes service level that occupants receive, so it must be done within the allowable range. In 2050, it is possible to not only improve the efficiency of appliances, equipment and building, but also to reduce energy consumption by the change of macro-frame and land-use. In this paper, considering these points, we analyzed the possibility of zero emission in the Japanese residential sector in 2050 through energy-saving measures and residential solar power generation, using a bottom-up simulation model. This model can reproduce the diversity of household energy consumption caused by their characteristics in region and national scale households, compare changes in energy consumption due to changes in equipment, behavior, and number of households on the same evaluation axis, and quantify the change in power demand by time.

 As the simulation result, without any measures added, the primary energy consumption in the Japanese household sector in 2013 and 2050 are 3080PJ and 1615PJ. Net energy consumption in 2050 is 532PJ. This indicates that to realize zero-emission in 2050, the current measure is not enough and more stringent measures need to be implemented.

 In this paper, three types of measures were added to create zero-emission in 2050 as follows: Improvement of equipment and housing energy efficiency, reduction of equipment number, and operation of macro-frame. By implementing these measures and installing solar cells in all detached houses, it is possible to realize zero-emission from the net annual energy consumption in 2050. Especially, the energy saving effect of the heating and hot water is large. From 2013 to 2050, energy consumption of other home appliances account for a relatively large proportion of overall household energy consumption. Further, it is suggested that as energy consumption reduced significantly, the energy consumption will be less affected by changes in macro frames. This indicates that a certain “minimum energy” exists.

 As the result of the load curve, most power generation deficiency days and power generation excess days occur on different seasons. Since it is impossible to store electricity in the residential batteries across seasons, only a small amount of electricity generated by solar cells is available to be used in the residential sector. For better use of the energy from the solar cell, it is needed to transfer the energy to other sectors or to develop an energy storage system that able to store energy for a long time.