Estimating CO2 emissions related to residential electricity consumption – the importance of using load and CO2-intensity data with a high temporal resolution

摘要

The reduction of CO2 emissions related to the energy use of buildings is one of the key challenges within the energy transition. We focus in particular on the electricity use of residential buildings, using measured consumption profiles with a high temporal resolution. It is important to consider the timing of residential electricity consumption because the CO2-intensity of electricity on the grid is not constant over time. Depending on which generators are producing electricity at each moment in time, the CO2-intensity in a particular region can fluctuate considerably. It is therefore beneficial from a CO2 perspective to move the demand for grid electricity towards times when the CO2-intensity is low and vice versa. The most straight-forward way to estimate the CO2 emissions related to the residential consumption of grid electricity is to multiply the total consumption over the estimation period (e.g. a year) with the average CO2-intensity of grid electricity in the same period. This can however result in a bad estimate, because grid electricity consumption may be heavily concentrated during hours of high or low CO2 intensity. Increasing the temporal resolution of both the consumption and the CO2 intensity may therefore provide a more accurate result. We estimate the difference between both calculation methods for a large set of residential buildings, to assess the value of using the more accurate method.