SETAC Conference 11-13 November 2013 Rome, Italy The (Exergetic) Life Cycle Assessment ((E)LCA) of microalgae production as feed for aquaculture: an environmental sustainability analysis Sue Ellen TAELMAN(a) S. De Meester(a), L. Roef(b), M. Michiels(b), J. Dewulf(a) (a) Research Group EnVOC, Faculty of Bioscience Engineering, Ghent University, Coupure Links 653, B-9000 Ghent, Belgium (b) Proviron Holding nv, G. Gilliotstraat 60, 2620 Hemiksem, Belgium

Introduction Aquaculture: feeding fish to fish principle is not sustainable Alternative for fish oil/meal production = ALGAE Microalgae are unicellular, mostly photo-autotrophic organisms They need water, light and inorganic nutrients to grow Some advantages: Very rich biomass Able to live of waste streams Higher photosynthetic efficiency Marginal land is sufficient Known disadvantages: Low cell density cultivation -> reflection on harvesting and processing Claimed to be a sustainable biomass resource -> correct? .

Research questions Examining the environmental sustainability of algae production in the new ProviAPT system Scenarios: Pilot 2012 (based on actual production runs) Two upscaling scenarios (2013 and 2015) Determining the potential of microalgae as fish feed application + benchmarking with traditional fish feed

Methods Exergy analysis on process level Thermodynamics: ‘all real processes generate entropy’ ‘all real processes generate loss of work potential’ Quality/quantity measurement of material & energy flows Process improvement Life Cycle Assessment (LCA), ISO standards 14000 & 14040 Functional unit: 1MJex System boundaries: cradle to gate Foreground: provided by Proviron Background: database ecoinvent v2.2 Climate change (IPCC,2007) Resource consumption (CEENE, 2007)

Cultivation Pilot 2012 240 m² Michiels, M. 2009 : Bioreactor. EP 2039753

Foreground system pilot 2012 Centrate Permeate

Forecast: First production scale 2015 Upscaling analysis (1)   Pilot 2012 Forecast: Pilot 2013 Forecast: First production scale 2015 Scenario (generic) Scale 240 m² 1320 m² 2.5 ha Location Belgium Spain Recycling of permeate and centrate (process C and D) No Yes, extra filtration on centrate Photobioreactor Area PBR 12 m² 26 m² Reactive area PBR 7 m² 21 m² Photosynthetic efficiency 1.2% on 12 m² 2.4% on 26 m² Areal productivity 4.59 g/m²/d 15.1 g/m²/d Volumetric productivity 0.53 g/l/d 1.25 g/l/d Efficiency fan 25 % 35 % 80 % (a) Efficiency circulation pump 11 % 80 % (b) Source CO2 bottled Flue gases Heat 200 W/m², 50% of the year at 50% of the peak power No extra heat necessary (a) based on document UNEP, 2006a (b) based on document UNEP, 2006b (c) Piek et al., 2012 (d) Sheehan et al., 1998

Forecast: First production scale 2015 Upscaling analysis (2)   Pilot 2012 Forecast: Pilot 2013 Forecast: First production scale 2015 Centrifuge Type Bowl centrifuge Hydrostop centrifuge Electricity consumption 15 kWh/m³ 3.5 kWh/m³ 0.95 kWh/m³(c) Drying Freeze dryer Drum dryer 59 kWh/kg DW 13 kWh/kg DW / Natural gas consumption 0.98 kWh/kg H2O(vapour)(d) (a) based on document UNEP, 2006a (b) based on document UNEP, 2006b (c) Piek et al., 2012 (d) Sheehan et al., 1998

Forecast: First production scale (2015) LCA: results (1)   Pilot plant (2012) Forecast: Pilot plant (2013) Forecast: First production scale (2015) Cumulative Energy Extraction from the Natural Environment (CEENE) MJex,CEENE/MJex DM 55.5 21.6 2.46 Renewable 0.58 0.18 0.11 Fossil 21.26 8.04 1.24 Nuclear 24.45 9.32 0.23 Metal ores 0.02 0.01 0.00 Minerals 0.17 Water 4.47 1.34 0.20 Land use 4.57 2.66 0.68 Atmosphere Carbon Footprint (CF) kg CO2,eq/MJex DM 1.76 0.64 0.09

LCA: results (2) CEENE (MJex,CEENE/MJex DM) IPCC (kg CO2,eq/MJex DM) Pilot 2012 Forecast Pilot 2013 Forecast First Production scale 2015 IPCC (kg CO2,eq/MJex DM) Pilot 2012 Forecast Pilot 2013 Forecast First Production scale 2015 *(Huysveld et al., 2011; Huysveld et al., 2013)

Conclusions and future research Recycling of water/nutrients and savings on energy use show important routes to make the overall production more sustainable Also upscaling, reactor design improvements, enhancement of photosynthetic yield and good choice of location contribute to an environmental progress Although additional efforts are required to improve the carbon footprint, in the near future algae production can reach a lower resource footprint (2.46 MJex,CEENE/MJex DM) than traditional fish feed (7.70 MJex,CEENE/MJex DM) Contact: sueellen.taelman@ugent.be +32 9 264 58 71