{"text_format":"3","workbook":"xls","n_sheets":2,"sheets":["Forest Wind Farm Calcs","C stock in trees"],"not_rendered":{"charts":1,"external_links":1},"read":"whole","date_system":"1900","formulas":"cached_only"}

{"sheet":"Forest Wind Farm Calcs","index":0,"n_rows":201,"n_cols":6,"rows_kept":201,"flags":["formulas_cached_only"]}
[]
[]
["CALCULATION WORKSHEET TO ACCOMPANY:"]
["MITCHELL, GRACE & HARRISON: \"CO2 PAYBACK TIME FOR A WIND FARM ON AFFORESTED PEATLAND IN THE UK\""]
["MIRES & PEAT, VOLUME 4"]
[]
[]
["ASSUMPTIONS"]
[]
[null,"WIND FARM & GRID VARIABLES"]
[null,null,"Turbine capacity (kW)",660,null,"Ardente et al. (2008)"]
[null,null,"Number of turbines / pad sites",11,null,"Ardente et al. (2008)"]
[null,null,"Wind farm lifetime (yrs)",20,null,"Ardente et al. (2008)"]
[null,null,"Turbine load factor (%)",{"v":0.27,"d":"27.00%"},null,"DECC (2009)"]
[null,null,"CO2 intensity of fossil grid (kg CO2  kWh-1)",0.605,null,"DECC (2009)"]
[null,null,"Wind farm lifecycle CO2 emissions without site disturbance (kg CO2)",{"v":3700000,"d":"3,700,000"},null,"Ardente et al. (2008)"]
[]
[null,"SITE DISTURBANCE & ECOSYSTEM VARIABLES"]
[null,null,"EXCAVATION & DEGRADATION"]
[null,null,"Length of access road per pad site (m)",500,null,"Nayak et al. (2008); Lindsay (2005); Lewis Wind Farm (2006)"]
[null,null,"Width of access roads (m)",5,null,"Lewis Wind Farm (2006)"]
[null,null,"Length of one side of square of turbine base excavation (m)",30,null,"Nayak et al. (2008); Lindsay (2005); Lewis Wind Farm (2006)"]
[null,null,"Width of buffer for access roads, both sides combined (m)",20,null,"Estimate, this study"]
[null,null,"Length of one side of square enclosing turbine base & buffer area (m)",50,null,"Estimate, this study"]
[null,null,"Ratio of hard standing excavation : turbine base excavation",1,null,"Hall (2006)"]
[null,null,"Area excavated for control building (ha)",2,null,"Lewis Wind Farm (2006)"]
[null,null,"Area excavated for substation (ha)",2,null,"Lewis Wind Farm (2006)"]
[null,null,"ECOSYSTEM"]
[null,null,"C stock, peat soil (kg C ha-1)",{"v":181000,"d":"181,000"},null,"Zerva et al. 2005"]
[null,null,"Soil C lost, clearfell (kg C ha -1)",{"v":81000,"d":"81,000"},null,"Zerva et al. (2005)"]
[null,null,"C stock, roots & branches (kg C ha-1)",{"v":47895,"d":"47,895"},null,"Green et al. (2007)"]
[null,null,"C stock, tree stems (kg C ha-1)",{"v":47895,"d":"47,895"},null,"Green et al. (2007)"]
[null,null,"C lost, tree stems (%)",{"v":0.57,"d":"57%"},null,"Harman et al. (1990)"]
[null,null,"Ecosystem C sequestration (kg C ha-1 yr-1)",{"v":5500,"d":"5,500"},null,"Magnani et al. (2007)"]
[]
[null,"CONVERSION FACTORS"]
[null,null,"Conversion C to CO2",{"v":3.6666666666666665,"d":"3.667"}]
[null,null,"Hours per year",8760]
[]
["CALCULATIONS"]
[]
[null,"(a) Wind farm production"]
[]
[null,null,"Wind farm production, annual (kWh)","[turbine capacity] * [hours per yr] * [turbine load factor] * [no. of turbines]"]
[null,null,{"v":17171352,"d":"17,171,352"}]
[]
[null,null,"Wind farm production, lifetime (kWh)","[wind farm production, annual] * [wind farm lifetime]"]
[null,null,{"v":343427040,"d":"343,427,040"}]
[]
[null,null,"Wind farm production, lifetime (MWh)","[wind farm production, annual / 1000]"]
[null,null,{"v":343427.04,"d":"343,427"}]
[]
[null,"(b) Avoided CO2 emissions: windfarm vs. fossil grid"]
[]
[null,null,"Gross CO2 avoided, annual (kg CO2)","[wind farm production, annual] * [CO2 intensity of fossil grid]"]
[null,null,{"v":10388667.959999999,"d":"10,388,668"}]
[]
[null,null,"Gross CO2 avoided, lifetime (kg CO2)","[wind farm production, lifetime] * [CO2 intensity of fossil grid]"]
[null,null,{"v":207773359.2,"d":"207,773,359"}]
[]
[null,"(c) calculation of excavated and degraded land area"]
[]
[null,null,"Excavated area, access roads, per pad site (ha)","[length of access road per pad site] * [width of access roads] / 10,000"]
[null,null,0.25]
[]
[null,null,"Excavated area, turbine bases, per pad site (ha)","[length of one side of square of turbine base excavation]2 / 10,000"]
[null,null,0.09]
[]
[null,null,"Excavated area, hard standings, per pad site (ha)","[total excavated area per pad site] * [ratio of hard standing excavation : turbine base excavation]"]
[null,null,0.09]
[]
[null,null,"Excavated area, utility buildings, allocation per pad site","([area excavated for control building] + [area excavated for substation]) / [no. of turbine pad sites]"]
[null,null,{"v":0.36363636363636365,"d":"0.36"}]
[]
[null,null,"Total excavated area per pad site (ha)","[excavated area, access roads] + [excavated area, turbine bases] + [excavated area, hard standings] + [excavated area, utility buildings]"]
[null,null,{"v":0.7936363636363636,"d":"0.79"}]
[]
[null,null,"Degraded area, access road buffer, per pad site (ha)","[length of access road per pad site] * [width of buffer for access roads] / 10,000"]
[null,null,{"v":1,"d":"1.00"}]
[]
[null,null,"Degraded area, pad site buffer, per pad site (ha)","[length of one side of square enclosing turbine base & buffer area]2 - [length of one side of square of turbine base excavation]2 / 10,000"]
[null,null,0.16]
[]
[null,null,"Total degraded area per pad site (ha)","[Degraded area, access road buffer, per pad site]+ [degraded area, pad site buffer, per pad site]"]
[null,null,1.16]
[]
[null,"(d) CO2 lost in excavated land"]
[]
[null,null,"Lost CO2 sequestration (kg CO2)","[total excavated area per pad site] * [ecosystem C sequestration] * [conversion C to CO2] * [wind farm lifetime] * [no. of pad sites]"]
[null,null,{"v":3521100,"d":"3,521,100"}]
[]
[null,null,"CO2 lost, peat oxidation (kg CO2)","[total excavated area per pad site] * [C stock, peat soil] * [conversion C to CO2] * [no. pad sites] "]
[null,null,{"v":5793809.999999999,"d":"5,793,810"}]
[]
[null,null,"CO2 lost, branches & roots (kg CO2)","[total excavated area per pad site] * [C stock, roots & branches] * [conversion C to CO2] * [no. pad sites] "]
[null,null,{"v":1533118.9499999997,"d":"1,533,119"}]
[]
[null,null,"CO2 lost, tree stems (kg CO2)","[total excavated area per pad site] * [C stock, tree stems] * [C lost, tree stems] * [conversion C to CO2] * [no. pad sites]"]
[null,null,{"v":873877.8014999998,"d":"873,878"}]
[]
[null,null,"Total CO2 lost, excavated area (kg CO2)","[lost CO2 sequestration] + [CO2 lost, peat oxidation] + [CO2 lost, branches & roots] + [CO2 lost, tree stems]"]
[null,null,{"v":11721906.7515,"d":"11,721,907"}]
[]
[]
[null,"(e) CO2 lost in degraded land"]
[]
[null,null,"Lost CO2 sequestration (kg CO2)","[total degraded area per pad site] * [ecosystem C sequestration]  * [conversion C to CO2] * [wind farm lifetime] * [no. pad sites]"]
[null,null,{"v":5146533.333333333,"d":"5,146,533"}]
[]
[null,null,"CO2 lost, peat degradation (kg CO2)","[total degraded area per pad site] * [soil C lost, clearfell] * [conversion C to CO2] * [no. pad sites] "]
[null,null,{"v":3789720,"d":"3,789,720"}]
[]
[null,null,"CO2 lost, branches & roots (kg CO2)","[total degraded area per pad site] * [C stock, roots & branches] * [conversion C to CO2] * [no. of pad sites]"]
[null,null,{"v":2240847.4,"d":"2,240,847"}]
[]
[null,null,"CO2 lost, tree stems (kg CO2)","[total degraded area per pad site] * [C stock, tree stems] * [C lost, tree stems] * [conversion C to CO2] * [no. of pad sites]"]
[null,null,{"v":1277283.0179999997,"d":"1,277,283"}]
[]
[null,null,"Total CO2 lost, degradaded area (kg CO2)","[lost CO2 sequestration] + [CO2 lost, peat degradation] + [CO2 lost, branches & roots] + [CO2 lost, tree stems]"]
[null,null,{"v":12454383.751333332,"d":"12,454,384"}]
[]
[]
[null,"(f) Total disturbed area CO2 emissions (kg CO2)",null,"[total CO2 lost, excavated area] + [total CO2 lost, degraded area]"]
[null,null,{"v":24176290.50283333,"d":"24,176,290.50"}]
[]
[]
[null,"(g) Wind farm lifecycle CO2 emissions with site disturbance (kg CO2)",null,"[wind farm lifecycle CO2 emissions] + [total disturbed area CO2 emissions]"]
[null,null,{"v":27876290.50283333,"d":"27,876,291"}]
[]
[null,"(h) Wind farm CO2 intensity and CO2 payback time"]
[]
[null,null,"Wind farm CO2 intensity, w/o site disturbance (g CO2 kWh-1)","1000 * [wind farm lifecycle CO2 emissions w/o disturbance] / [wind farm production, lifetime]"]
[null,null,{"v":10.773758525246002,"d":"10.8"}]
[]
[null,null,"Wind farm CO2 payback time, w/o site disturbance (days)","([wind farm lifecycle CO2 emissions w/o site disturbance] / [gross CO2 avoided, annual]) * 365"]
[null,null,{"v":129.99741691619147,"d":"130"}]
[]
[null,null,"Wind farm CO2 payback time, w/o site disturbance (years)","[wind farm CO2 payback time, w/o site disturbance] / 365"]
[null,null,{"v":0.35615730661970263,"d":"0.36"}]
[]
[null,null,"Wind farm CO2 intensity, with site disturbance (g CO2 kWh-1)","1000 * [wind farm lifecycle CO2 emissions with site disturbance] / [wind farm production, lifetime]"]
[null,null,{"v":81.1709249884148,"d":"81.2"}]
[]
[null,null,"Wind farm CO2 payback time, with site disturbance (days)","([wind farm lifecycle CO2 emissions with site disturbance] / [gross CO2 avoided, annual]) * 365"]
[null,null,{"v":979.4177725874845,"d":"979"}]
[]
[null,null,"Wind farm CO2 payback time, with site disturbance (years)","[wind farm CO2 payback time, with disturbance] / 365"]
[null,null,{"v":2.683336363253382,"d":"2.68"}]
[]
["SENSITIVITY CALCULATIONS FOR WIND FARM WITH SITE DISTURBANCE"]
["10% INCREASE IN FACTOR"]
[]
[{"$nulls":3},"Wind farm ","Wind farm "]
[null,"(a) CO2 Intensity",null,"CO2 intensity","CO2 intensity"]
[{"$nulls":3},"(w/site disturbance)","(w/disturbance, factor x 1.1)"]
[null,null,"Factor","(g CO2 kWh-1)","(g CO2 kWh-1)","% change"]
[]
[null,null,"Load factor",81.2,73.8,{"v":-0.09113300492610843,"d":"-9.1%"}]
[null,null,"CO2 intensity of fossil grid",81.2,81.2,{"v":0,"d":"0.0%"}]
[null,null,"Wind farm lifecycle CO2 emissions",81.2,82.2,{"v":0.012315270935960632,"d":"1.2%"}]
[null,null,"Excavated area per pad site (ha)",81.2,84.6,{"v":0.041871921182266014,"d":"4.2%"}]
[null,null,"Degraded area per pad site (ha)",81.2,84.8,{"v":0.04433497536945796,"d":"4.4%"}]
[null,null,"C stock, peat soil (kg C)",81.2,82.9,{"v":0.020935960591133007,"d":"2.1%"}]
[null,null,"Soil C lost, clearfell (kg C)",81.2,82.3,{"v":0.013546798029556495,"d":"1.4%"}]
[null,null,"C stock, roots & branches (kg C ha-1)",81.2,82.3,{"v":0.013546798029556495,"d":"1.4%"}]
[null,null,"C stock, tree stems (kg C ha-1)",81.2,81.8,{"v":0.00738916256157629,"d":"0.7%"}]
[null,null,"Ecosystem C sequestration (kg C ha-1 yr-1)",81.2,83.7,{"v":0.030788177339901468,"d":"3.1%"}]
[]
[]
[{"$nulls":3},"Wind farm","Wind farm"]
[null,"(b) CO2 payback time",null,"CO2 payback time","CO2 payback time"]
[{"$nulls":3},"(w/site disturbance)","(w/disturbance, factor x 1.1)"]
[null,null,"Factor","(days)","(days)","# days"]
[]
[null,null,"Load factor",976,890,-86]
[null,null,"CO2 intensity of fossil grid",976,890,-86]
[null,null,"Wind farm lifecycle CO2 emissions",976,992,16]
[null,null,"Excavated area per pad site (ha)",976,1021,45]
[null,null,"Degraded area per pad site (ha)",976,1023,47]
[null,null,"C stock, peat soil (kg C)",976,1000,24]
[null,null,"Soil C lost, clearfell (kg C)",976,993,17]
[null,null,"C stock, roots & branches (kg C ha-1)",976,993,17]
[null,null,"C stock, tree stems (kg C ha-1)",976,987,11]
[null,null,"Ecosystem C sequestration (kg C ha-1 yr-1)",976,1010,34]
[]
[]
["CHART: SENSITIVITY ANALYSIS FOR WIND FARM WITH SITE DISTURBANCE AND 10% INCREASE IN FACTOR"]
["CO2 PAYBACK TIME"]
["WIND FARM WITH SITE DISTURBANCE"]
[]
[null,null,"Factor","% Change","Days"]
[null,null,"Windfarm load factor",{"v":-0.07992565055762081,"d":"-8.0%"},-86]
[null,null,"CO2 intensity of fossil grid",{"v":-0.07992565055762081,"d":"-8.0%"},-86]
[null,null,"Wind farm lifecycle CO2 emissions",{"v":0.01486988847583643,"d":"1.5%"},16]
[null,null,"Excavated area per turbine",{"v":0.041821561338289966,"d":"4.2%"},45]
[null,null,"Degraded area per turbine",{"v":0.04368029739776952,"d":"4.4%"},47]
[null,null,"C stock, peat soil",{"v":0.022304832713754646,"d":"2.2%"},24]
[null,null,"Soil C lost, clearfell",{"v":0.015799256505576207,"d":"1.6%"},17]
[null,null,"C stock, roots & branches",{"v":0.015799256505576207,"d":"1.6%"},17]
[null,null,"C stock, tree stems",{"v":0.010223048327137546,"d":"1.0%"},11]
[null,null,"Ecosystem C sequestration",{"v":0.031598513011152414,"d":"3.2%"},34]

{"sheet":"C stock in trees","index":1,"n_rows":65,"n_cols":13,"rows_kept":65,"flags":["formulas_cached_only"]}
[]
[]
[{"$nulls":5},"18-yr stand",null,null,"20-yr stand",null,"19-yr stand"]
[{"$nulls":5},"Phillips (2000)",null,null,"Zerva et al. (2005)",null,null,"Green et al. (2007)"]
[{"$nulls":4},"%","t C ha-1","Ann. Incr.","%","t C ha-1","Ann. Incr.","%","t C ha-1","Ann. Incr."]
[{"$nulls":3},"stems",{"v":0.5,"d":"50%"},35,{"$nulls":4},{"v":0.43,"d":"43%"}]
[{"$nulls":3},"bark",{"$nulls":6},{"v":0.07,"d":"7%"}]
[{"$nulls":3},"branches",{"$nulls":6},{"v":0.16,"d":"16%"}]
[null,null,"ABOVE","foliage",{"$nulls":6},{"v":0.1,"d":"10%"}]
[{"$nulls":3},"deadwood",{"$nulls":6},{"v":0.06,"d":"6%"}]
[]
[{"$nulls":3},"Subtotal",null,35,{"$nulls":4},{"v":0.8200000000000001,"d":"82%"},74,{"v":3.9,"d":"3.90"}]
[]
[{"$nulls":3},"fine roots",{"$nulls":4},4.8,null,"*","*","*"]
[{"$nulls":3},"small roots"]
[null,null,"BELOW","medium roots",{"$nulls":4},24,0.9]
[{"$nulls":3},"large roots"]
[]
[{"$nulls":3},"Subtotal",null,35,null,null,28.8,0.9,{"v":0.18,"d":"18%"},17,0.89]
[]
[null,null,"ECOSYSTEM","Total",null,70,{"$nulls":5},91,4.79]
[null,null,"TOTALS"]
[{"$nulls":3},"R ",{"$nulls":7},{"v":0.22972972972972974,"d":"0.23"}]
[]
[]
[{"$nulls":3},"n","A red box indicates the study did not differentiate by subclass, therefore the value represents the sum of the components"]
[]
[]
[{"$nulls":3},"R = relative belowground biomass to aboveground biomass"]
[{"$nulls":3},"*  \"All roots over 2 mm were removed. Coarse >50 mm, medium 10-50 mm, small 2-10 mm. Fine roots were not sampled.\""]
[]
[]
[null,null,"Derive Harwood C content of trees (roots, stems, branches):",{"$nulls":4},"t C ha-1"]
[]
[null,null,"Using Phillips (2000) 18-yr stand…"]
[]
[null,null,"Total tree storage ",{"$nulls":4},{"v":70,"d":"70.00"},null,"Phillips (2000)"]
[null,null,"Add two years growth to equal 20-yr stand",{"$nulls":4},79.58,null,"Green et al. (2007); see table above"]
[null,null,"Stems & bark = 50%",{"$nulls":4},39.79,null,"Phillips (2000); Green et al. (2007)"]
[null,null,"Roots & branches = remainder",{"$nulls":4},39.79,null,"Phillips (2000); Green et al. (2007)"]
[]
[{"$nulls":3},"convert to kg C ha-1",null,"stems",null,{"v":39790,"d":"39,790"}]
[{"$nulls":5},"roots & branches",null,{"v":39790,"d":"39,790"}]
[]
[null,null,"...OR, using Green et al. (2007) 19-yr stand"]
[]
[null,null,"Total tree storage",{"$nulls":4},{"v":91,"d":"91.00"},null,"Green et al. (2007)"]
[null,null,"Add one year growth to equal 20-yr stand",{"$nulls":4},95.79,null,"Green et al. (2007); see table above"]
[null,null,"Stems & bark = 50%",{"$nulls":4},{"v":47.895,"d":"47.90"},null,"Phillips (2000); Green et al. (2007)"]
[null,null,"Roots & branches = remainder",{"$nulls":4},{"v":47.895,"d":"47.90"},null,"Phillips (2000); Green et al. (2007)"]
[]
[{"$nulls":3},"convert to kg C ha-1",null,"stems",null,{"v":47895,"d":"47,895"}]
[{"$nulls":5},"roots & branches",null,{"v":47895,"d":"47,895"}]
[]
[]
[null,null,"...OR, using R from Green et al. (2007) to estimate from Zerva et al.'s (2007) belowground value"]
[]
[null,null,"Coarse & fine roots estimate from Zerva et al. (2007)",{"$nulls":4},{"v":28.8,"d":"28.80"},null,"Zerva et al. (2007) Table 1"]
[null,null,"Aboveground estimate using R = 0.23",{"$nulls":4},{"v":125.36470588235294,"d":"125.36"},null,"Green et al. (2007)"]
[null,null,"Total tree C storage",{"$nulls":4},{"v":154.16470588235293,"d":"154.16"}]
[null,null,"Stems & bark = 50%",{"$nulls":4},{"v":62.68235294117647,"d":"62.68"},null,"Phillips (2000); Green et al. (2007)"]
[null,null,"Roots & branches = remainder",{"$nulls":4},{"v":62.68235294117647,"d":"62.68"},null,"Phillips (2000); Green et al. (2007)"]
[]
[{"$nulls":3},"convert to kg C ha-1",null,"stems",null,{"v":62682.35294117647,"d":"62,682"}]
[{"$nulls":5},"roots & branches",null,{"v":62682.35294117647,"d":"62,682"}]