The Cobber is a small-scale, compressed gas engine that works by making steam and using it to drive a reciprocating engine. At the foundation of this technology is our patented engine, in which every stroke is a power stroke, delivering incredible torque and outstanding fuel efficiency.
The prototype for the first-generation Cobber is already generating up to 5kw electricity, and 20 kW heating. And it makes this power through the efficient combustion of renewable and locally sourced biomass.
High Efficiency Furnace
Because of the rugged nature of our technology, this 21st century steam engine can be powered with all manner of low-grade woody fuel. The Cobber’s mini- furnace combusts solid fuel in the most efficient manner possible and very little of the heat is lost to the environment. Low-grade fuels suitable for the Cobber include nut shells, woody weed species, wastepaper and cardboard, carpenters and builders’ off-cuts and forest litter.
Patented Boiler and Water Tube Flash Steam Boiler
At the heart of the Cobber are two patented technologies, the water tube flash steam boiler and the compressed gas engine. The small scale water tube boiler, which requires only 20 litres of water to start, generates dry steam which, after passing through the compressed gas engine is then condensed and returned to the feed water tank for reuse.
The engine turns a flywheel, producing high-torque mechanical power. This flywheel then turns an alternator and produces up to 5kw of steady 240-volt electricity. The electricity produced is enough to power a homestead, workshop, or even a small energy conscious community.
More than just electricity – The Cobber’s Heat Energy Recovery Unit (HERU)
As well as producing up to 5kw of electricity, the Cobber also produces useful heat. The exhaust steam leaving the engine still contains thermal energy. This thermal energy is recovered from the steam by our Heat Energy Recovery Unit (HERU) – a water cycling heat exchanger. When the Cobber is connected to a thermal storage tank and hydronic heating circuit it provides bountiful space heating. The HERU also provides potable hot water for all the normal uses – showers, baths, laundry, dishwashing – or any other situation where hot water is required. Please click here to see the heating circuit and hot water setup at our Renewable Energy Demonstration Site (REDS).
The Cobber can be integrated with other renewable energy technology and energy storage systems
The Cobber has been designed so that it can stand alone as a totally independent ‘off grid’ system. But the Cobber is also designed to integrate with other renewable energy systems.
Many off-grid renewable energy and battery systems have a back-up diesel or petrol generator as an essential part of the system. These fossil-fuelled generators are there to provide the system with power when solar or wind power aren’t available, and to condition and recharge battery banks. The Cobber is the first truly renewable alternative to these fossil-fuelled generators and is designed to replace these generators, making so called ‘hybrid renewable’ systems fully independent pure renewable systems.
Water Distillation Circuit in Development
Work has already begun on the design of a water distillation circuit for the Cobber.
According to the latest figures from the World Health Organisation, around one third of the world’s population still does not have access to clean drinking water. Uniflow is dedicated to providing a system that can give communities in developing countries access not only to electricity and hot water, but clean drinking water too.
Rotary Mechanical Power
Thanks to Ted Pritchard’s patented engine, every stroke of the Cobber’s engine is a power stroke. This means that the heavy flywheel of the Cobber provides an incredibly stable and powerful source of high torque rotary power.
The rotary mechanical power produced by the Cobber will be similar to the PTO (Power Take Off) systems on small farm tractors. This system will be able to provide rotary mechanical power to separate attachments or applications such as direct drive water pumps, seed sorting machines, air compressors, hydraulic systems, industrial cement mixers, and many more.
Multiple Use Steam Circuit
The Cobber is capable of producing dry and wet steam. Steam and high-pressure water are used for many applications, such as the dry steam sterilisation of medical equipment (field autoclave), dry cleaning, steam ovens, pressure washers, and more.
Research and design work still needs to be done in order to equip the Cobber with an optional modular steam circuit capable of delivering the diverse benefits of on-demand process steam.