Turboden's ORC biomass cogeneration plant at Varna-Bolzarno Italy

Turbo-charging biomass to energy

Italian manufacturer Turboden believes its organic rankine cycle waste-to-energy generators are a viable, sustainable solution for Australia’s waste management needs.

When it comes to turning renewable sources into heat and electrical power, Turboden can rightly claim to be a world-leading expert.

Founded in Italy and acquired by Mitsubishi Heavy Industries in 2013, Turboden has been developing and producing Organic Rankine Cycle (ORC) turbogenerators since 1980. This continually-updated, state-of- the-art equipment generates heat and power from renewable sources, and recovers heat in industrial processes.

ORC is a well-known technology for energy production, mostly in biomass and geothermal applications.

Environmental concern over climate change, a desire to make use of waste streams and countering rising oil prices are stimulating the uptake of this efficient, clean and reliable way of producing electricity.

The company has vast experience in helping firms obtain value from waste streams, having supplied over 260 biomass and nine waste-to-energy plants around the world.

This past September, its first biomass plant in Australia was commissioned. The unit at Wagin, WA, is built next to an oat mill. The waste oat husks are burnt to generate heat and clean electricity, helping to reduce operating costs and emissions.

Turboden’s Business Development Manager for Oceania, Carlo Minini, is now based in Melbourne to leverage this first project and share the technology with the Australian market.

How ORC turbogenerators work

ORC technology works like a traditional steam turbine, but instead of using water vapour, the ORC 
unit vaporizes a high-molecular-mass organic fluid. With high cycle efficiency, this achieves strong electric performance, and has the benefits
of slower turbine rotation, lower pressure, and no erosion of metal componentry, all which contribute
to a longer working life and minimal downtime.

Turboden believes there are several factors that make ORC technology 
a successful alternative to traditional steam turbines, which have added benefits when coupled with waste streams.

Significantly, it has low operation and maintenance costs (about half that of steam turbines) as it is fully automated and doesn’t need an operator or specialist engineer to function. It remains highly efficient at partial loads, offering flexible operations, increased operating hours and more megawatt hours (i.e. energy), and therefore revenue, generated in a year.

Also, the ORC technology does
 not use water in the thermodynamic cycle and is particularly suited to dry cooling (compared to wet cooling towers, where water is chemically treated and gets consumed). So it can operate without consuming any water, useful for regions with scarce water supplies and for environmentally-conscious projects.

An Australian W2E solution?

With Australian local governments
and environmental solutions providers considering their directions for
waste management in the future, Turboden believes its technology
offers a useful, viable option for the country – to avoid some waste streams going to landfill, to fit with Australian conditions, and to generate a revenue stream from selling the energy outputs.

“Australia is blessed with abundance of renewable energy resources, including those that are suitable for the ORC,” says Carlo. “There is plenty of sun for concentrated solar power, or thermodynamic solar. And there is plenty of wood biomass, food processing biomass, green waste and other waste material.”

This Australian scenario fits in
with two of Turboden’s main areas of application. The first is using biomass co-generation or tri-generation for the likes of district heating networks, combined cooling, heating and power (CCHP) in large buildings, timber drying in sawmills and sawdust drying in wood pellet factories. The second is waste heat recovery by producing electrical power from exhaust streams in industrial processes, such as waste incineration.

“In Australia, I am particularly positive about the potential for our ORC units in bioenergy facilities, such as forestry or food processing, for small to medium size waste-to- energy plants, such as up to 20 to 30 megawatts electric,” adds Carlo.

He adds that biomass is an ideal energy source because it is readily available, can be stored for long periods and is often cost-effective. The plants would burn the biomass or biogas, and use the heat to raise vapour from the organic fluids to generate electricity.

In his assessment since becoming more familiar with the different industries in the country, Carlo sees a number of interesting opportunities in Australia. He identifies one as the resources and energy sector, where waste heat can be recovered from large gas engines or gas turbines used in mining sites to generate “fuel-free” electricity.

“Waste to energy is also an obvious option as an alternative to steam turbines in incineration or gasification of waste, or on gas flares and with gas engines in landfills,” adds Carlo.

Technical information on Turboden’s ORC turbogenerator applications can be found on the company website or by direct enquiry to carlo.minini@ turboden.com.