Homepage

Workshop on

Supercapacitors and Energy Storage 2016

From research through industrial applications up to nuclear fusion plants

Date and location

The Workshop was held in ENEA, Via Enrico Fermi, 45, Frascati (RM), on 13 May 2016.

Introduction

Supercapacitors (also known as ultracapacitors, electrochemical capacitors or double-layer capacitors) feature exceptional capacitance values (even hundreds or thousands of farads), several orders of magnitude higher than traditional devices.

Energy storage

Until recently, batteries were the only affordable energy storage system in conventional applications. Nowadays, supercapacitors are a sound alternative with high power density, fast recharge and long lifetime (up to 1 million of charge/discharge cycles). On the other hand, since the energy density available in supercapacitors is lower than in batteries, the most common application is in hybrid (batteries/supercapacitors) energy storage systems, for example to sustain the load peaks, to reduce the system weight or to extend its lifetime.

Present scenarios

The supercapacitor technological development and cost reduction (together with the advancements in the supporting electronics) opened new scenarios in electrical and electronic systems, offering extraordinary opportunities for applied research and industry. In fact, the number of manufacturers is constantly growing as the estimated business turnover.

Test and modelling

Supercapacitor modeling and simulation are still open issues. A supercapacitor (module) cannot be functionally reduced to a simple capacitance, even including series and parallel leakage resistances. For example, the equivalent capacitance may strongly decrease with frequency. Also the experimental methods to identify the modeling parameters are under investigation.

Potential applications in nuclear fusion

Supercapacitors were introduced or proposed in several fields, as smart grids or electrical vehicles. However, their benefits are particularly relevant in applications with limited duty cycle, as large experimental plants. The ENEA Research Center in Frascati is the main Italian institution working in the field of nuclear fusion. A nuclear fusion facility (tokamak) can be regarded as a giant electrical machine. Up to the 40% of the costs for the realization of international projects like ITER, JT-60SA or the new proposal DTT (to be built in Frascati) are related to the electrical and electronic systems (power supplies, converters, electrical delivery, motors, radiofrequency sources, control and automation, diagnostics). The total power of a tokamak as DTT may reach hundreds of megawatts with a variable profile. Such values can be managed only in two ways (often in conjunction): by connecting the plant to a high-voltage grid or by exploiting some form of energy storage (rotating machines and flywheels or, in special cases, superconducting magnets). In absence of an adequate energy storage, the plants can be realized only in locations with extraordinary power capabilities (even the maximum of the entire country), after preventive authorization and under special power delivery contracts. The convenience of supercapacitors is evident considering that in those cases the peak power is relatively short with a sufficient recovery time.

Future prospects

Supercapacitor technologies are relatively new on the market. The achievable performances are expected to be higher and higher at lower and lower costs. A significant contribution is expected by nanotechnology. The process improvement would reduce the component unbalance and the need of compensation devices. At the same time, currents and commutation frequencies would be increased by power electronics developments.

Per gli ingegneri iscritti all'Ordine (only for Italian engineers interested in CFP credits)

L'Ordine degli Ingegneri della Provincia di Roma, in collaborazione con il Centro Ricerche ENEA di Frascati, propone ai propri iscritti questo seminario tecnico gratuito. La partecipazione al seminario rilascia 6 CFP, ai fini dell'aggiornamento delle competenze professionali ex DPR 137/2012 e successivo regolamento approvato dal Ministero della Giustizia.

Program and presentations

Please, consider that some contents were confidential. Therefore, some presentations are not available for download or were adapted for distribution on the web.

After Workshop

Relax after Workshop, including local "porchetta".