Clifton Brown, J. C.

Jones, Michael B.

Styles, D.

English

University of Kentucky

University of Kentucky UKnowledge International Grassland Congress Proceedings 21st International Grassland Congress / 8th International Rangeland Congress Mitigation of Greenhouse Gas Emissions by the Energy Grass, Miscanthus X giganteus Michael B. Jones Trinity College Dublin, Ireland D. Styles Environmental Protection Agency, Ireland J. C. Clifton Brown Institute of Grassland and Environmental Research, UK Follow this and additional works at: https://uknowledge.uky.edu/igc  Part of the Plant Sciences Commons, and the Soil Science Commons This document is available at https://uknowledge.uky.edu/igc/21/8-1/20 The 21st International Grassland Congress / 8th International Rangeland Congress took place in Hohhot, China from June 29 through July 5, 2008. Proceedings edited by Organizing Committee of 2008 IGC/IRC Conference Published by Guangdong People's Publishing House This Event is brought to you for free and open access by the Plant and Soil Sciences at UKnowledge. It has been accepted for inclusion in International Grassland Congress Proceedings by an authorized administrator of UKnowledge. For more information, please contact UKnowledge@lsv.uky.edu. 瞯 ]888　 瞯 　 Multifunctional Grasslands in a Changing World 　 Volume Ⅰ 　Grasslands/Rangelands Resources and Ecology ——— Climate Change and Impact on Grasslands/RangelandsMitigation of greenhouse gas emissions by the energy grass ,Miscanthus × giganteusM . B . Jones1 , D . S ty les 2 and J . C . Cli f ton Brown31 Department o f Botany , School o f Natural Sciences , T rinity College Dublin , Dublin 2 , I relandE‐mail : mike .j ones＠ tcd .ie ; 2 Env ironmental Protection A gency , Clonskeagh , Dublin 14 , I realnd ;3 Plant Breeding and Crop Genetics , Institute o f G rassland and Env ironmental Research , Plas Gogerddan , Aberystw y th ,Dy f ed SY23 3EB , UKKey words : energy crops , GHG emissions , carbon sequestration , MiscanthusIntroduction As a result of the increasing demand for biomass energy crops to replace the fossil fuels oil , gas and coal there hasbeen a renewed interest in identifying suitable energy crops which are close to carbon neutral . Biomass crops not only have thecapacity to reduce fossil fuel consumption , but can aid in greenhouse gas ( GHG) mitigation by acting as carbon sinks . Hencethe construction of a full GHG budget for these crops is of vital importance . Reliable budgets depend on validation from longterm grow th trials but because of the relatively recent interest in dedicated energy crops these trials are few in number . Clif tonBrown et al (２００７) have recently reported on １６ years of grow th trials with the perennial rhizomatous C４ grass Miscanthus ×giganteus , Life‐cycle assessment has been used to synthesise the net environmental impact of energy crop cultivation comparedwith conventional agricultural land uses , and energy crop combustion compared with fossil fuels , with particular regard toGHG emissions .Materials and methods A field trial of Miscanthus × giganteus has been established near Cashel , Co . Tipperary , Ireland ( ５２°３９′N , ０７°５０′W) since June １９９０ . From １９９１ to ２００５ , yield was determined in late February or early March ( average ９ t dry‐matter ha‐１ a‐１ ) . To determine the amount of carbon sequestered to the soil by ２００５ , １５ years after planting , one soil core wastaken from each of the eight replicate plots and the Miscanthus derived organic carbon present in the soil was detected bymeasuring the change in the １３C stable isotope signal ( average ０ .６７５ t C ha‐１ a‐１ ) . For details of this procedure see Clif tonBrown et al . ( ２００７ ) . A life‐cycle approach was used to quantify the major GHG emission sources associated with theproduction of useful heat ( kWhth ) from Miscanthus that is harvested and pelleted before combustion ( Styles and Jones , ２００７ &２００８)‐these calculations were updated with Cashel data .Results Life‐cycle GHG emission reductions ( average per hectare) possible where Miscanthus displaces conventional fuels forelectricity generation and heat production , and dominant agricultural land‐uses .Conclusions Fuel chain GHG emissions attributable to Miscanthus are between ７０％ and ８８％ lower than those for oil , gas andelectric heating fuel chains , and ８６％ lower than for the peat‐electricity fuel chain . However , long‐term soil C sequestrationwhen Miscanthus is grown on either grassland or tillage land exceed cultivation emissions , and , along with possibledisplacement of marginal agricultural production , could result electricity and heat production better than C‐neutral . With life‐cycle GHG reductions of between ９ .６８ and ３７ .１５ t CO２ eq . ha‐１ a‐１ , energy crop electricity and heat production represent highlyefficient land‐use options for GHG mitigation .ReferencesClif ton Brown JC , Breuer J , Jones MB (２００８) Carbon mitigation by the energy crop , Miscanthus . Global Change Biology １３ ,２２９６‐２３０７ .Styles D , Jones MB ( ２００７) Energy crops in Ireland : quantifying the potential life‐cycle greenhouse gas reductions of energy‐crop electricity . Biomass and Bioenergy ３１ , ７５９‐７７２ .Styles D , Jones MB (２００８) Miscanthus and willow heat production — an effective land‐use strategy for greenhouse gas emissionavoidance in Ireland . Energy Policy , ３６ , ９７‐１０７ .Fuel displaced Fuel GHG- Useful Energy GHG Land-use Displaced Soil CO2 LUGHG intensity energy reduction displaced LUemis. seq. reduction kg CO2 eq. kWh-' kWh a·' I CO2 eq . a·' I- I CO2 eq. a·' I- z z Peat (elec)' 1.15 17,472 19.33 w Tillage 3.49 4.25 4.03 >- w :IE (!) :IE Oil (heat)" 0.331 40,961 12.54 w 0.00 4.25 2.32 a: w 0 Set-aside w~ :5 z ...J Gas (heat)" 0.248 40,961 9.14 D.. Extensif 0.00 2.48 0.54 w D.. .,, .,, Electric (heat)" 0.624 40,961 24.54 i5 Sheep 3.75 2.48 4.29 i5 w .,, 5.24 2.48 5.77 ::J Cattle c COMBINED ENERGY AND LAND-USE MIN 9.68 z Dairy 12.07 2.48 12.60 GHG REDUCTION (t CO2 eq. a·') :5 MAX 37.15 

Mitigation of Greenhouse Gas Emissions by the Energy Grass, \u3cem\u3eMiscanthus\u3c/em\u3e X \u3cem\u3egiganteus\u3c/em\u3e

https://uknowledge.uky.edu/cgi/viewcontent.cgi?article=2930&amp;context=igc

Mitigation of Greenhouse Gas Emissions by the Energy Grass, \u3cem\u3eMiscanthus\u3c/em\u3e X \u3cem\u3egiganteus\u3c/em\u3e

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