Combined Solar Hot Water and Electricity Production

Eco Investor March 2009 Edition

South Australian company Cogen Microsystems Pty Ltd is aiming to commercially release by 2010 a cogeneration system that can produce both hot water and electricity for households and small commercial properties.

The company says the system will be available at a lower installed cost than competing technologies and will provide significant carbon emissions savings.

The Rankine cycle micro-cogeneration technology uses a heat engine and low cost solar thermal collector, and is claimed to be unique in its suitability for the residential and small commercial user as it can provide all of the heating and hot water needs of a home while also generating electricity for use in the home.

Surplus electricity can be sold into the grid, said the company.

Cogen said its micro CHP (Combined Heat and Power) systems run very quietly and require almost no maintenance, while installation is as easy as replacing the conventional boiler used in hydronic heating systems.

“Widespread implementation of microcogeneration is arguably the most significant change that can be made in the short to medium term, to minimise climate change,” said Cogen.

The company is seeking strategic partners to assist in getting the product into the marketplace. There will be two sizes: 2.5 kWe for domestic applications and 10 kWe for large residential and small commercial use.

We understand that home heating boiler replacement is often a distress purchase. It is thus critical that our system can slot straight in where the boiler came out. And even more importantly, it must cost not much more than a conventional boiler - otherwise the payback time will be unattractive. Our system meets these critical requirements with its simplicity. Our innovative approach to Rankine cycle engine design eliminates many moving parts and replaces them with electronic control and actuation.

The system uses water as the working fluid, making it a small steam engine and eliminating issues with exotic working fluids.

The company’s intellectual property covers “core aspects of the heat engine technology and the control system that allows us to connect directly to the grid without the need for a costly inverter”. Cogen has won a Climate Ready grant of $814,000 for the project.