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Time for a rethink: How to max the humble mini-grid
What’s in the pipeline for climate ideas? We’re continuing our occasional series of innovation spotlights.
![](https://media.beehiiv.com/cdn-cgi/image/fit=scale-down,format=auto,onerror=redirect,quality=80/uploads/asset/file/eb021273-28a8-4a58-ac24-f59f14915d8c/Mini_Grid_2.jpg)
What’s in the pipeline for climate ideas? We’re continuing our occasional series of innovation spotlights.
For Africa to have a thriving green economy able to absorb substantial new investment, new ideas must lead the way.
The focus: Today, we’re looking at how African mini-grids can benefit from ambitious thinking. This is based on work done by CrossBoundary’s Mini-grid Innovation Lab.
For a profile the lab’s leader, see the next story below
A. Second-life batteries: Castoffs from the Global North power many African markets. Take cars and clothes. Most are sold used. What might that look like for power units?
After three years, many batteries are no longer efficient enough for electric vehicles but can still be used in stationary situations.
Second-life power units from cars could be integrated into mini-grids; that may reduce unit cost by up to 40%.
This becomes more attractive as the e-mobility sector grows, boosting the supply of used batteries.
The capacities and maintenance needs of used batteries are not yet fully understood. Two South African companies, Blue Volt and Revov, are testing refurbishment and management systems for mini-grids.
B. Modular mini-grids: Scaling de-centralised systems as use grows over time is hard. Expansions are rarely seamless. Hence, most mini-grids are overbuilt and under-utilised (30%-40%). Capital is locked up needlessly. How to fix this?
Studer is working on a smart inverter that makes it possible to add batteries of different ages to a single system. One can then expand over varying distances.
OKRA has developed mesh grids for 4-5 households (software balances loads). Mesh grids sit in between solar home systems and mini-grids. They can connect users at the periphery of mini-grids, which is otherwise too costly.
C. Sub-metering: Perhaps not all power uses should be charged equally. Tariffs differentiated within an account would make it possible to subsidise climate-friendly uses. Current meters don’t allow this.
PowerPay is developing a chip that makes it possible to track consumption at the appliance level.
Developers could offer competitive tariffs on different usages. Watching TV? Pay the full rate. Switching from charcoal or gas to an electric cooker? Pay less for the power used.
Industrial applications are also under consideration. An example: Reducing the cost of power for a grain mill when switching from diesel to electricity.