The Concept

Problems in electrification projects in sub-Sahara Africa are often related to high rates for electricity/unit – especially for private households. On the other side, if the government limits the rates down to 0.05 EUR/kWh or even lower this is attractive for the people using it but not for potential investors due to very low revenue for reinvestment. One possibility to overcome this problem is the use of refurbished 2nd life components for mini-grid systems in combination with an independent quality seal or certificate. The most expensive components of such system are the solar panels and the lithium-ion battery (LIB) storage system. The VoltaView concept uses both, refurbished and quality tested 2nd life LIB and solar panels with an efficiency > 85% compared to new panels. The estimated lifetime for both will be > 10 years. This leads to significant reduction of investment costs for a mini-grid on one hand and on the other hand such solution gives sustainable contribution to the aspect of circular economy. In addition, the VoltaView mini-grid system includes a water purification system, applying a special combination of different filter and UV-C disinfection. The complete system is installed in a 20 foot sea container and all hardware installation has been done in Germany before shipping the container.

As an example, a VoltaView mini-grid-25 installed at sub-Saharan Africa is estimated to produce about 15.000 kWh electricity per year and up to 2.000 liters clean drinking water per day. Charging 0.05 EUR/kWh and 0.014 EUR/liter clean water and assuming a rural community with 300 inhabitants using 0.2 kWh/person and day and 5 liter clean water/day and person will give a revenue to reinvest the VoltaView mini-grid-25 system within 3 years.

As a consequence, the VoltaView mini-grid concept provides both electricity and clean drinking water at affordable price for rural communities and in addition it gives a contribution for reduction of worldwide CO2 emissions.

Technical Specifications

The VoltaView concept was developed by Fraunhofer HHI and Clausthal University of Technology, both Germany.

It provides a mini-grid solution based on 2nd life photovoltaics and 2nd life lithium-ion battery (LIB) storage in combination with a water purification system using a special filter combination and UV-C disinfection. The complete system is installed into a 20 foot sea container. For transportation the solar panels are stored in the container. At the place of operation the panels have to be mounted on the roof of the container, after that the mini-grid can be operated right away. All hardware installation has been done in Germany before shipping the container. There is no additional air conditioning installed, a fresh air flow inside the container is established by sensor-controlled louvre windows. The 2nd life LIB storage system meets the highest safety requirements applying a sensor-controlled sprinkler system in combination with F500 fire extinguishing agent.

  • 20 feet sea container serves as housing for the complete mini-grid
  • 2nd life LIB power storage available with capacity 25, 50 or 75 kWh
  • Integrated energy management system
  • Power storage system modular organized in 19 inch slot, easy upgrade possible, also easy replacement of aged LIB modules
  • 2nd life solar panels on top of the container (4-6 kWp)
  • Natural climatization of the container by sensor-controlled louvre window system
  • Clean drinking water production of up to 2000 liters/day
  • German quality seal available
  • WiFi and Internet readout and control option

The VoltaView mini-grid-25 (5 kWp solar and 25 kWh LIB capacity) provides electricity for about 50 households plus up to 5 mini-business (e.g. sewing rooms, juice production, small shop, ice cubes for fish storage) and up to 2000 liters of clean drinking water/day for a rural community village with about 300 inhabitants.

The VoltaView mini-grid is easy to install, has low maintenance costs and can easily be connected to the local power grid system. It gives light for all and offers establishing mini-business opportunities for locals in rural communities. Because of the low cost 2nd life LIB storage system and the 2nd life solar panels (both refurbishes and provided with a German quality seal) investment costs for the VoltaView mini-grid are significantly reduced compared to a mini-grid system using new components.