Starfish’s newest Associate, Ian Gesch, has successfully completed the ‘Green Glasshouses’ (Sustainable Environment Management for Commercial Greenhouses) research project.
The purpose of this research was to inform horticulturists who are currently reliant upon LPG for glasshouse heating about options for renewable and sustainable energy resources. The renewable sources considered include solar PV, Concentrated Solar Thermal, wind, geothermal, bio-digestion and biomass. Integration of product and waste streams from other processes, particularly as applied to carbon dioxide enrichment inside the facility, were also considered.
The Green Glasshouses project identified options for sustainable alternatives to natural gas and LPG combustion in commercial greenhouses. A range of case study greenhouses were chosen in order to compare and contrast the experiences and practices of each.
The findings identified that many sustainable heating and CO2 enrichment options exist for greenhouse operations when compared to the consumption of fossil fuels. Most of these, however, have low or no appeal due to relative cost (such as heat pumps and wind power), complexity (generating syngas from industrial or agricultural processes) or physical footprint (such as solar energy collection).
Industrial symbioses also have low applicability due to the continued placement of greenhouses in regional areas as opposed to locating them adjacent to sources of waste heat and carbon dioxide.
However, there is scope for the development of a properly functioning carbon market in concert with the tailoring of greenhouse design and operational practices to the Australian landscape. This has the potential to create opportunities for strengthening the business viability of commercial greenhouses, adapting to climate change and augmenting food security and export.
The recommendations identify the need for additional research into:
- Existing and potential demand for energy CO2 in commercial greenhouses
- CO2 capture, scrubbing and reuse from small coal and biomass furnace exhaust
- Greenhouse environment management practices that increase exposure times of CO2 enrichment such as reduced venting and active cooling of the growing space
- The applicability of the Emissions Reduction Fund to the use of waste CO2 for environment management in commercial greenhouses
- Development of tools and methods that simplify the calculation of the true cost of CO2 enrichment and investigation into the potential for industrial symbioses between commercial greenhouses and producers of waste heat and CO2.
An electronic copy of the abridged report is available by contacting Ian Gesch (see Starfish Associates).