How phase-change materials are saving lives

The Dulas solar-powered direct-drive vaccine fridge uses phase-change materials to store vaccines more effectively, helping save human lives.

The Dulas solar-powered direct-drive vaccine fridge uses phase-change materials to store vaccines more effectively, helping save human lives.

By Jason Deign

Phase-change materials (PCMs) are boldly going into an energy storage realm where even the most modern battery technologies have failed to deliver: saving lives.

Dulas, a Welsh renewable energy technology company, is using PCMs in place of batteries as an essential component of solar-powered direct-drive refrigerators for off-grid vaccine storage in developing countries.

On Monday the company announced a contract to supply 345 of its VC200 fridges to health and aid agencies working in Yemen, Sierra Leone and Nigeria.

The company said the deal represented “a significant expansion” of its partnerships with the World Health Organisation (WHO), the United Nations Children’s Fund (UNICEF) and the Institute of Human Virology in Nigeria.

Dulas will be sending 60 fridges to the Institute of Human Virology, 143 to the WHO in Yemen and 142 to UNICEF in Sierra Leone. “There is the potential for further orders in the near future,” said the company. 
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ZBB commissions co-op installation

ZBB Energy Corporation has announced the commissioning of a ‘first ever’ ZBB EnerSection 125kW bi-directional inverter with lead-acid batteries in a utility-owned demonstration facility with onsite solar PV and wind turbine generation. The system includes ZBB EnerSection DC inputs for regulating power flows to and from four lead-acid battery sets.

The installation will demonstrate the numerous economic, operational, strategic and environmental value streams accomplished by prioritising and optimising renewables in unison with peak grid usage in distributed locations, says the company.

“The battery bank cycling will reduce our system losses, reduce our peak demand charges and improve efficiency on our system,” explained Warren Jones, distribution engineer on the project for Lower Valley Electric Co-op, the customer.

New battery charging algorithm increases capacity 30% for electric loco cells

It’s not just what you do, it’s the way you do it. That’s what researchers into lead acid batteries found, when they successfully designed a charging algorithm to overcome some of the aging processes that plague this type of energy storage unit.

The batteries in question are the one thousand individual cells powering Norfolk Southern Railway No. 999, the first all-electric, battery-powered locomotive in the United States. Like all acid-lead batteries, they suffer from a sulphation, a condition where lead sulphate builds up on the electrodes and, as an insulator, impedes cell performance. The Penn State University research team overcame it by a simple variation in charging rate for the battery.

The improvement of 30%, without the need for any physical or chemical changes in the batteries, is obviously good news for anyone wanting to promote the use of lead-acid energy storage in heavy applications such as this.

The future for lead-acid batteries

Dwarfed by lithium-ion for years, the original car battery technology, lead-acid, has not been a favourite for recent energy storage applications due to its slow charging rates and short cycle life. Although GM used lead-acid technology in its original 1997 EV1 two-seater, it was clear these heavy, bulky batteries were simply not up to the job, and lithium-ion soon took over.

But, says Pike Research, lead-acid has a healthy future in both the grid storage market and transportation. According to the analyst firm, the developing technologies of advanced lead-acid batteries will capture roughly 25% of the global battery-based grid storage market and will be worth USD$6.8 billion in 2020.

Transportation applications, however, will make up the lion’s share for advanced lead-acid battery revenues.

Lead-acid battery storage for 9 HES units

GS Battery is supplying lead-acid batteries as part of nine hybrid energy storage (HES) systems, reports Energy Manager Today. The HES units are being deployed to store energy supplied by photovoltaic arrays, for later use in charging electric vehicles.

Three units are destined for the Tennessee Valley Authority SMART Station Program, and six storage-only systems will be part of a complete electric vehicle charging station which is part of Oak Ridge National Labs’ Department of Energy electric vehicle charger trial programme.

Australia’s biggest energy storage battery project

Hydro Tasmania has awarded Ecoult a contract to supply the largest battery-based renewable energy storage system in Australia. Oz-based Ecoult will be supplying a 3MW/1.6MWh storage system based on its lead-acid UltraBattery technology, which will have the capacity to power an entire island of over 1,700 inhabitants for up to 45 minutes.

The energy storage component is part of the King Island Renewable Energy Integration Project, which, it is hoped, will lower CO2 emissions by 95% through the use of sustainable clean energy sources, including bio-diesel.