Contribution of energy storage to the transition from net zero to zero energy buildings

Recently, intensive technological development in the field of energy efficiency of buildings has occurred, which should enable the transition from nearly zero (nZEB), through net zero (NZEB) to ultimate zero energy buildings (ZEB). The last stage will also require a transition from the grid to onsite storage of each energy carrier needed for the operation of building technical systems (BTS). In the article, the method of optimization of energy storage is presented and demonstrated on the example of all-glass NZEB office buildings in different climates. The impact of energy storage was estimated by production matching fraction fpr,match and by the building autonomy factor (AUT). The metrics were determined by dynamic modelling of buildings with south-facing glazed BIPV fa?ades. It was found that optimum energy storage capacities are in the range between 0.01 and 0.06 kWh/m2 for heat storage, 0.03 to 0.08 kWh/m2 for cold storage and 0.03 to 0.04 kWh/m2 for batteries per 1 m2 of useful area of the building. By integrating optimized energy storage in BTS, the fpr,match could be increased from 43% to 61% and AUT from 44% to 54%, indicating that energy storage significantly contributes to the transition of NZEB towards ZEB.

Automated summary

Intensive technological development in building energy efficiency has enabled the transition from nearly zero energy buildings to net zero energy buildings to ultimate zero energy buildings. By optimizing energy storage, buildings can significantly increase their self-sufficiency and contribute to the energy transition.