Power bank for grid storage

Finding new ways to store sunlight

The downside of rapid economic growth, as China knows only too well, is that the power grid comes under increasing pressure. The imbalance between power demand and supply leads to unscheduled power outages, which have a negative effect on the local economy.

Renewables are certainly the answer, but the challenge is in the storage of energy produced so that the demands on the grid of peak power consumption can be met.

Zbest Power Co. Ltd, one of five recipients of the WWF Climate Solver awards, has met that challenge with an innovative solution which they have called Power Bank.

“Climate change has become an increasingly important global challenge, and the Climate Solvers we have recognised are providing key solutions for phasing out fossil fuels and reducing carbon emissions,” says Sze Ping LO, CEO of WWF-China.

After eight years of technical development, the company has developed a zinc-bromine flow battery, an emerging technology that provides a viable energy storage option for the fast-growing renewable energy market. The company has also built up in-house capability for developing key components and materials for the zinc-bromine flow battery including bipolar electrodes, membranes, electrolytes and flow frames, which could reduce the cost of the battery to half current levels.

This year the company will launch an innovative business model called Electricity Bank which is designed to create a network of energy storage units. The cost of storing excess solar power is low, which allows for its sale back to the national power grid when needed at higher price and demand.

“We are excited about this kind of technology,” says Stefan Henningsson, advisor for the WWF’s Global Climate and Energy initiative. “This will greatly enhance solar power integration, and consequently reduce the wastage of clean energy, coal burnt and CO2 emissions stemming from China.”

Some challenges still remain for Zbest Power Co. Ltd to overcome, including the traditionally conservative attitude of utilities towards new technologies and the time required for the regulatory framework to adapt to energy storage. The development team is also working hard to improve the performance of the stack material in order to enhance the batteries’ performance.