13 June 2013

Fraunhofer ISE researchers receive SEMIKRON Innovation Award for off-grid village power supply in threshold countries

At the PCIM Europe 2013 power electronics show in Nuremberg, Germany (14-16 May), the researchers Dr Olivier Stalter, Florian Reiners, Michael Eberlin and Sebastian Franz from Fraunhofer Institute for Solar Energy Systems ISE in Freiburg, Germany - together with Frank Seybold from KACO new energy GmbH of Neckarsulm, Germany – jointly received the annual SEMIKRON Innovation Award for their concept ‘Innovative power Electronics for the next-generation village energy supply’.

The SEMIKRON Innovation Award is bestowed for innovation in projects, prototypes, services and novel concepts in power electronics in Europe. The foundation honors innovations that generate a high potential social benefit and improve energy efficiency, preservation of resources, sustainability and environmental protection. Laureates are elected in cooperation with the ECPE European Centre for Power Electronics e.V, research network. The main award is endowed with €10,000.

Picture: SEMIKRON Innovation Award 2013.

From a total of 19 applicants this year, the jury selected the Fraunhofer ISE power electronics technology for facilitating a complete off-grid village power supply in developing and threshold countries. With this technology the entire electricity for remote towns can be centrally generated and supplied with renewable energy.

“About 1.6 billion people in the world do not have access to electricity,” says project leader Dr Olivier Stalter. “Since most of these countries are located in the Earth’s sun belt, solar electricity is an obvious solution that has become more attractive in the past years due to the decrease in the price of photovoltaic (PV) modules,” he adds. “Up to now, such solar PV systems were limited to low powers of about 100W. Our system applies the newest technological developments of the industrial nations to meet the needs of remote village communities and larger consumers such as hospitals or smaller firms.”

Picture: Schematic of system for off-grid village power supply with PV and diesel generator. Fraunhofer ISE’s developments in power electronics are highlighted in blue. 

The system components developed at Fraunhofer ISE consist mainly of a standalone 125kW inverter and a 51kW charger for battery voltages up to 1000V. The basic idea was to design the system for high voltages and high internal switching frequencies using the latest semiconductor devices such as super-junction MOSFETs and silicon carbide (SiC) diodes. This allows low currents and low losses, reducing device dimensions, cooling demand, material use and costs. Meanwhile, losses can be reduced by 60% compared with conventional units, it is reckoned. The inverter and charger operate with efficiencies of up to 98% and 99%, respectively.

Especially for developing countries, it is important to keep the technology simple, says Fraunhofer ISE. Whereas before, units with extensive cables and switching had to be connected in parallel to achieve high capacities, now only one unit is needed. High-tech devices and continuous digital control allow maximum flexibility. PV systems from 350V up to 1200V and battery systems with a nominal voltage from 650V up to 1000V can hence be used. In most cases, diesel generators are installed already on site and therefore an energy management system controls the different generators, the battery charging and the electricity supply.

Tags: Fraunhofer ISE

Visit: www.semikron-stiftung.com

Visit: www.ise.fraunhofer.de