Assessing bidirectional EV charging for employer parking: A case study of the MAHLE chargeBIG demonstrator in Stuttgart

Highlights

Abstract

This paper investigated the economic and operational viability of bidirectional charging (BC) technology through a real-world case study of the MAHLE chargeBIG demonstrator in Stuttgart, Germany, which is equipped with 101 electric vehicle (EV) charging points in the company car park. Using empirical charging data recorded in 2023, a mixed-integer linear programming model was developed to optimize energy costs, self-consumption, and renewable energy integration through price-based demand response (DR) with quarter-hourly market prices, while accounting for battery degradation effects and infrastructure investment costs. This research aimed to provide actionable insights for companies considering the adoption of BC technology by quantifying its economic and operational impacts under realistic industrial conditions. The results indicated that, depending on the scenario and context, BC achieved a break-even compensation value of €0.66 – €1.78 per discharged kWh (excluding battery degradation) through peak shaving and price-based DR. Correspondingly, the maximum annual saving per EV at the company level varied between €610 and €2,018 with average savings of €211 – €893/EV/yr, depending on the specific scenario and vehicle availability. Moderate increases in charging station power, from 7.2 kW to 11 kW AC or from 10 kW to 20 kW DC significantly enhanced cost efficiency and operational flexibility, while a further increase to 30 kW DC provided negligible additional benefits. The findings suggest that, under our applied market conditions and system constraints, energy arbitrage on the electricity market was not economical due to user constraints, prevailing price structures, and the impact of battery degradation. In this study, the primary economic benefits of BC in company settings were found to stem predominantly from peak load reduction, alongside a 22% decrease in degradation costs, and variable price-based DR, positioning BC as a key enabler of cost-efficient and flexible energy management in industrial environments.

Juli 2026

E-Flotten als Energiespeicher nutzen: Praxisbeispiel aus der Industrie
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Short-Term Utilization Forecasting of Electric Vehicle Charging Infrastructures

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A heuristic for bi-directional charging of fleet EVs
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Kategorien und Anwendungsfälle zum bidirektionalen Laden von Elektrofahrzeugen

Mai 2025

Hier geht es zum LinkedIn-Beitrag

Willingness of employees to accept bidirectional charging at the workplace

AutorInnen aus dem BiFlex-Konsortium: David Meyer, Luca Husemann, Heike Proff

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Leave-One-Out-, Bootstrap- and Cross-Conformal Anomaly Detectors

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