Klaus-Henning Ahlert

Sensitivity analysis of the economic benefits from electricity storage at the end consumer level

The article presents the results of simulations based on a linear optimization model of a storage system that calculates the economic benefits of distributed storage devices at the end consumer level by determining the cost optimal charge-discharge-schedule. The primary objective of the storage application is arbitrage accommodation. Particularly, parameters for a li-ion-based and a lead-acid-based storage system are simulated. All parameters of the model are varied and analyzed regarding their impact on the economic benefits. The simulation results quantify these impacts and show that the costs per storage capacity unit (EUR/kWh) and the efficiency degrees of the storage system have the highest impact. Additionally, the price spreads as well as the distribution of the market price curve in relation with the distribution of the consumers load curve (demand) influence the achievable benefits significantly. Overall, the model reveals a saving potential of 17% on total cost for the reference case.

Economic benchmark of charging strategies for battery electric vehicles

This paper investigates a smart charging strategy and a Vehicle-to-Grid (V2G) strategy and benchmarks the economic benefits for the electric vehicle (EV) owner against a zero-intelligence charging strategy in a simulation-based analysis. Smart charging optimizes the timing of charging the EV and V2G additionally allows for reselling electricity to the energy market.

Assessing the Impact of Price Forecast Errors on the Economics of Distributed Storage Systems

This article analyzes the economic impact of price forecast errors on the optimal operation schedules of distributed (battery) storage systems.The presented simulation model extends a linear optimization model that achieves up to 17% annual savings for a storage system in an environment with dynamically changing electricity prices and under the assumptions of ex-ante known load and price data. The main contribution of this paper is to replace the deterministic load and price curves by imperfect forecasts of which the effect of price forecast errors is systematically analyzed. All results are benchmarked against the optimal result of the basic model.The main finding is that the underlying storage optimization model performs with a high robustness against price forecast errors. E.g., up to 10% Mean Absolute Percentage Error (MAPE) for day-ahead price forecasts lead to less than 10% deviation from the optimal result. I.e., the storage model yields up to 15% annual savings vs. 17% in the optimal case.

Kapazitätsmanagement in auftragsorientierten Produktionsnetzwerken — Ein flexibilitätsorientierter Ansatz

In auftragsorientierten Produktionsnetzwerken sind durch das Kapazitatsmanagement zwei Arten von Unsicherheit zu berucksichtigen: Unsicherheit der Kapazitatsnachfrage und des -angebots. Um diese Unsicherheiten zu handhaben, wird ein flexibler Ansatz vorgeschlagen, der eine auslastungsorientierte Preisbildung mit zwei Arten der Bereitstellung von Netzwerkkapazitat kombiniert: Kapazitatspool und ad-hoc-reservierbare Kapazitat. Das zentrale Problem der Dimensionierung des Kapazitatspools wird iterativ in einem dezentralisierten Planungsprozes gelost, wobei das Gegenstromprinzip zur Anwendung gelangt. Im vorliegenden Beitrag werden die zugrundeliegenden formalen Modelle der Unternehmungs- und der Netzwerkebene sowie das Abstimmungsverfahren dargestellt.

Driving Profile Generator

The driving profile generator is a tool to generate an arbitrary number of car driving profiles such that the resulting profiles are in the same form as those reported in the latest German Mobility Panel (MOP), a large field study that reports car mobility for about 12.000 individuals in Germany. The profile generator described in this report is able to generate simulated driving patterns for four different groups of persons: employees, part time employees, retired people, and unemployed people. Each generated profile comprises all car movements of an individual within one week. For each of these trips several different pieces of information are provided, in particular the start of the trip, the duration of the trip, and the kilometers driven throughout the trip. To make the generated driving profiles follow patterns similar to those in the empirically observed driving profiles of the MOP, the panels database has been statistically analyzed and the results are used as the basis for the profile generator.

Economics of Distributed Storage Systems: An economic analysis of arbitrage-maximizing storage systems at the end consumer level

Increasing the shares of Renewable Energy Sources (RES) and Distributed Energy Resources (DER) is one of the most important levers in many countries to cope with the environmental, political, and economic challenges of future energy supply. The underlying research question of this thesis is whether Distributed Storage Systems (DSS) at the end consumer level can economically foster the integration of intermittent and non-dispatchable resources by providing demand-side flexibility.