The solar energy storage solution capable of delivering on demand carbon neutral heating and cooling.

Company Details

Melbourne, Australia
Not Fundraising

Management Team

Stuart Donaldson avatar

Stuart Donaldson

Founder & Managing Director

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The problem we're solving:

A major issue in the transition to renewables is a lack of affordable storage. Without storage, solar panels can only be used when the sun is shining and, when it’s not, backup from the grid is required. Batteries provide part of the solution, but they’re expensive and can’t store enough kilowatt hours for heating and cooling - and heating and cooling actually accounts for one third of all energy consumption.

Our solution:

Drawing on the extensive design, engineering, and fabrication experience of our team at Polyweld, our successful plastics fabrication business, we’ve developed HVACTES, our storage solution for solar power that will provide an on demand supply of carbon neutral energy for heating and cooling.

The system comprises a patented water tank that stores hot and chilled water, a controller, and data analytics. Using weather forecast, consumption and other data, it becomes a smart storage system that will power conventional heating and cooling units to match the customer’s heating and cooling needs. A safety system instantly cools the fluid to a safe temperature if required. The system is modular and scalable.

Our differentiator:

HVACTES is an affordable low cost energy storage system for heating and cooling. It enables full utilisation of all the energy solar panels can capture and can provide up to two months storage.

Compared with battery storage, which currently costs approximately $250 per KWh, a 2.5m3 HVACTES will store 500 KWh for a target price of $25 per KWh. As fossil fuels are phased out in coming years and potentially become more expensive, HVACTES can offer certainty for heating and cooling costs into the future.

Our biggest achievement:

HVACTES is one module of a larger polygenerational system - Conservasphere, which was pitched at the Climate Launchpad competition in 2019 and selected in Victoria as a finalist for the national competition.

Stuart has a proven track record in successful patents, having developed ‘Axitex’ a popular load restraint truck curtain system that is the mainstay of Polyweld Pty Ltd, his profitable fabrication business servicing the transport industry.