Daaboul, J.; Moriarty, P.; Honnery, D. Green Energy Prospects of Electricity Generated from Short-Rotation Woody Crops—Quantifying the EROIg of Bioelectricity. Sustainability2023, 15, 16430.
Daaboul, J.; Moriarty, P.; Honnery, D. Green Energy Prospects of Electricity Generated from Short-Rotation Woody Crops—Quantifying the EROIg of Bioelectricity. Sustainability 2023, 15, 16430.
Daaboul, J.; Moriarty, P.; Honnery, D. Green Energy Prospects of Electricity Generated from Short-Rotation Woody Crops—Quantifying the EROIg of Bioelectricity. Sustainability2023, 15, 16430.
Daaboul, J.; Moriarty, P.; Honnery, D. Green Energy Prospects of Electricity Generated from Short-Rotation Woody Crops—Quantifying the EROIg of Bioelectricity. Sustainability 2023, 15, 16430.
Abstract
The IPCC’s sixth assessment report projects 15% to 43% (44 EJ/y – 310 EJ/y) of global primary energy to be generated by biomass in 2050 across multiple GHG mitigation scenarios. That report also emphasises the importance of electrification to meet GHG reduction targets. With increased reliance on electric power, and increased appeal to biomass, bioenergy for electricity is expected to play a major role in future energy markets. What makes the bioenergy solution more attractive is its reported reasonable Energy Return on Investment (EROI). However, generation at large scale is projected to be greatly dependent on crops and plantations. This shifts the GHG emissions concern to be concerns over land use and other emissions integrated in the bioenergy lifecycle. It is therefore vital to know whether the potential of electricity generation from biomass outweighs environmental impact of bioenergy. This paper evaluates the potential of biomass electricity mainly generated from short rotation woody crops combustion in generating green energy. This is done using the “Green EROI (EROIg)” quantification methodology, which indicates the net energy generated to society after investing in ecosystem maintenance energy (ESME). ESME is a non-monetary weighting mechanism of an entity’s different lifecycle environmental impacts. This study found that the EROIg of bioelectricity is marginally larger than unity when converted to its primary equivalent form (EROIg-PE) which indicates that the technology is somewhat energetically viable if its production was to be green. Three design options were proposed to improve bioenergy’s EROIg performance, these include adding 20% waste wood in the combustion mix, staggered harvesting and plantation to achieve annual harvest and pelletizing wood. This approach appeared to improve the EROIg especially for pelletizing, due to its simultaneous reduction in storage and transport costs, making the production energetically and environmentally viable even at a 1 : 1 secondary : primary ratio with an EROIg of 1.11 and an EROIg-PE of 3.17. We conclude with the discussion of the multiple indirect advantages of growing crops that can be used for energy generation, and a discussion on how this technique can be used alongside others to help them generate cleaner energy while facing the current global climate, biodiversity and waste issues.
Copyright:
This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
