Impact of residential heat pumps and photovoltaics on low-voltage grid reinforcements under varying insulation levels

Abstract

The European Union’s 2050 climate-neutrality goal necessitates extensive deployment of low-carbon technologies (LCTs) like heat pumps and rooftop photovoltaic systems in dwellings. However, integrating these into low-voltage (LV) grids can cause grid issues (e.g., voltage deviation, feeder overloading), often requiring grid reinforcements. This study uses a techno-economic approach to calculate the grid reinforcement costs under various residential LCT integration and insulation scenarios in representative rural and urban grids in Germany and Italy. Two cost calculation methods (maximum and average) are compared. Results indicate that, compared to the average cost calculation method, the maximum cost calculation method generally gives a higher cost under the same LCTs integration rate. Increasing LCT integration raises costs while improving residential dwelling insulation reduces them. The estimated reinforcement cost for rural and urban zones in Germany and Italy is significant and can be up to more than a billion euros. Improving residential insulation levels can reduce costs significantly for both German and Italian grids. The results and methodology presented can help grid operators and policymakers deploy LCTs in LV grids resiliently and cost-effectively.