Producing biomass: Biomass types: Crop residue: Grape waste
The Australian wine industry generates substantial quantities of biomass, such as grape marc and stalks, yeast lees and wastewater sludge. This waste material has the potential to be converted to energy.

Winery waste

Waste streams from the wine-making industry include:
  • grape marc – the skin and pips that remain after crushing
  • lees – the residue from the fermentation process
  • wastewater sludge
Australian wine producers are losing out by not benefiting from the energy value inherent in these waste streams, according to the Australian Wine Research Institute (AWRI).
Grape marc is the skins and pips that remain after the grapes have been crushed.

Photo: Econnect Communication

Benefits of converting winery waste to energy

As energy prices continue to rise, the business case for bioenergy is particularly compelling in regional areas where energy costs have risen sharply, according to the Australian Wine Research Institute. Wine producers “could reduce their energy costs by 50% or even more” by generating renewable energy from waste biomass.

Evaluating the economics

Disposal methods

Converting grape marc to energy is one of the opportunities identified in EPA South Australia’s 2001 Review of opportunities for the re-use of winery industry solid wastes [PDF, 224 kb].

The report quantifies the winery waste in South Australia and describes the issues and opportunities with disposal methods, including:
  • supplying winery solid waste to a local distiller
  • composting and spreading it on the vineyard
  • sending it to landfill
  • selling it to an external composting company
  • selling it or using it for stockfeed.

To justify the cost of a bioenergy plant, the report recommends forming a central collection agency so that large quantities of solid waste are brought to a central point.

EPA SA report: Opportunities for the re-use of winery industry solid wastes
Options for converting winery waste to bioenergy

The Australian Wine Research Institute’s Riverina node has evaluated the technology and economics of 13 renewable energy scenarios for wine producers, the following 8 of which are powered by biomass:
  • Scenario 1: Non-fermentation refrigeration electricity is supplied via a biomass gasifier. The gasifier converts grape marc to syngas, which is then fed to an internal combustion engine to drive a generator.
  • Scenario 2: All refrigeration electricity is supplied via a biomass gasifier (as per scenario 1).
  • Scenario 4: A biomass boiler is used to supply heat to an absorption chiller for ferment cooling only.
  • Scenario 5: A biomass boiler is used to supply heat to an absorption chiller year-round for non-vintage refrigeration.
  • Scenario 6: Site electricity is supplemented using gasification technology.
  • Scenario 11: Supplementary electricity is supplied by an anaerobic digester. The digester is used to produce biogas that is directed to an internal combustion engine to drive a generator.
  • Scenario 12: Supplementary refrigeration is supplied by anaerobic-digestion-powered refrigeration compressor.
  • Scenario 13: Site electricity is supplemented using Organic Rankine Cycle technology. Biomass is fed to a combustion furnace, and heat from the furnace is used to drive an Organic Rankine Cycle engine to produce electricity via a generator.


Scenarios 6 and 13 had the highest projected grid savings (both 49%) with payback projected to be about 5 years.

For more on projected payback periods and grid savings, download the one-page summary of the results of the AWRI evaluation [PDF, 265 kb].

Gasification was seen as a promising technology and a detailed study was performed: Utilisation of winery waste biomass in fluidised bed gasification and combustion [PDF].

Evaluate the options for your winery

Wineries can use AWRI’s bioenergy calculator [Excel spreadsheet] to evaluate each of the 13 renewable energy options for their winery.

Storing grape marc

Grape marc is a highly seasonal product and needs to be carefully stored to prevent deterioration, mould and pests.

The AWRI is trialling different anaerobic storage techniques and treatments to identify the most practical and effective option for storing grape marc, according to their July 2014 newsletter article, Maximising the potential of grape marc. One option they are exploring is baling grape marc.

Contacts

Col Stucley

Enecon

Suite 5, 651 Canterbury Road, Surrey Hills, Victoria 3127
Phone: +61 (03) 9895 1250

cstucley@enecon.com.au
ADI Systems Ltd

ADI Systems

ADI Systems (Asia Pacific), 50 Yeo Street, Neutral Bay, NSW 2089
Phone: 1.800.751.806 (toll free)

asiapacific@adi.ca
Peter Godden

The Australian Wine Research Institute

Waite Precinct, Hartley Grove cnr Paratoo Road, Urrbrae, Adelaide, SA 5064 , Manager - Industry Engagement and Application
Phone: 08 83136198

Peter.Godden@awri.com.au
Ben Manfield

Australian Tartaric Products

1074 Boonoonar Road, Colignan, VIC 3494, General Manager
Phone: 03 5029 1450

ben.manfield@australiantartaric.com.au