Table 4.

Equations used for the calculation and normalization of the indicators

Indicator ID and name	Calculation method	Eq	Variables
GHGm: Mitigation of GHG emissions	$\mathrm{GHGm}=M^{\ast }=\frac{e^{M_t}}{e^M}$ $M=\frac{G_{\mathrm{ref}}-G_b}{G_{\mathrm{ref}}}$	(1)	$M^{\ast }$•, normalized mitigation of GHG emissions (—) $M_t$•, threshold of the mitigation of the GHG emissions, expressed as fraction (—) $M$•, mitigation of GHG emissions by the bioenergy system, expressed as fraction (—) $G_{\mathrm{ref}}$•, life cycle GHG emissions of the reference system (g CO2eq/MJ) $G_b$•, life cycle GHG emissions of the bioenergy system (g CO2eq/MJ)
PMe: Particulate matter emissions	$\mathrm{PMe}={\mathrm{PM}}^{\ast }=\frac{\mathrm{PM}}{{\mathrm{PM}}_t}$	(2)	${\mathrm{PM}}^{\ast }$•, normalized emissions of particulate matter (—) $\mathrm{PM}$•, particulate matter concentration in flue gases (industrial end-use [mg/m3]) or in ambient air (end-use in or affecting enclosed spaces [μg/m3]) ${\mathrm{PM}}_t$•, threshold particulate matter concentration in flue gases (industrial end-use [mg/m3]) or in ambient air (end-use in or affecting enclosed spaces [μg/m3])
COe: Carbon monoxide emissions	$\mathrm{COe}={\mathrm{CO}}^{\ast }=\frac{\mathrm{CO}}{{\mathrm{CO}}_t}$	(3)	${\mathrm{CO}}^{\ast }$•, normalized emissions of carbon monoxide (—) $\mathrm{CO}$•, carbon monoxide concentration in flue gases (industrial end-use [ppmV]) or in ambient air (end-use in or affecting enclosed spaces [mg/m3]) ${\mathrm{CO}}_t$•, threshold carbon monoxide concentration in flue gases (industrial end-use [ppmV]) or in ambient air (end-use in or affecting enclosed spaces [mg/m3])
WINT: Water intensity	$\mathrm{WINT}=I_b^{\ast }=\frac{I_b}{I_t}$ $I_b=\frac{w_b}{E_b}$	(4)	$I_b^{\ast }$•, normalized water intensity of the bioenergy system (—) $I_b$•, water intensity of the bioenergy system (m3/kWh) $I_t$•, threshold of the water intensity of the reference end-use energy in Mexico: for electricity generation (= 0.011 m3/kWh) or for heat generation (0.025 m3/GJ) $w_b$•, freshwater consumption in the stages of biomass transformation, energy generation, and end-use (m3/a) $E_b$•, energy generated in the bioenergy system (kWh/a)
WEUT: Contribution to water eutrophication	$\mathrm{WEUT}={\mathrm{PC}}_{\mathrm{eq}}^{\ast }=\left\{\begin{array}{c}{\mathrm{COD}}^{\prime }\forall \mathrm{C}{\mathrm{OD}}^{\prime }\ge 1\mathrm{and}{\mathrm{TN}}^{\prime }<1\\ {\mathrm{TN}}^{\prime }\forall \mathrm{C}{\mathrm{OD}}^{\prime }<1\mathrm{and}{\mathrm{TN}}^{\prime }\ge 1\\ \begin{array}{c}\frac{{\mathrm{PC}}_{\mathrm{eq}}}{{\mathrm{PC}}_{\mathrm{eq},t}}\forall \mathrm{C}{\mathrm{OD}}^{\prime }\ge 1\mathrm{and}{\mathrm{TN}}^{\prime }\ge 1\\ \frac{{\mathrm{PC}}_{\mathrm{eq}}}{{\mathrm{PC}}_{\mathrm{eq},t}}\forall \mathrm{C}{\mathrm{OD}}^{\prime }<1\mathrm{and}{\mathrm{TN}}^{\prime }<1\end{array}\end{array}\right)$   ${\mathrm{COD}}^{\prime }=\frac{\mathrm{COD}}{{\mathrm{COD}}_t};{\mathrm{TN}}^{\prime }=\frac{\mathrm{TN}}{{\mathrm{TN}}_t}$   ${\mathrm{PC}}_{\mathrm{eq}}=\frac{0.022\bullet \mathrm{COD}+0.42\bullet \mathrm{TN}}{1000}$ ${\mathrm{PC}}_{\mathrm{eq},t}=\frac{0.022{\bullet \mathrm{COD}}_t+0.42\bullet {\mathrm{TN}}_t}{1000}$	(5)	${\mathrm{PC}}_{\mathrm{eq}}^{\ast }$•, normalized concentration of phosphate equivalent (—) ${\mathrm{COD}}^{\prime }$•, ratio of chemical oxygen demands (system to threshold) (—) ${\mathrm{TN}}^{\prime }$•, ratio of total nitrogen content (system to threshold) (—) ${\mathrm{PC}}_{\mathrm{eq}}$•, concentration of phosphate equivalent in water discharges ($\mathrm{kg}{\mathrm{PO}}_{4\mathrm{eq}}^{3-}/{\mathrm{m}}^3$) ${\mathrm{PC}}_{\mathrm{eq},t}$•, threshold of the concentration of phosphate equivalent in water discharges $(\mathrm{kg}{\mathrm{PO}}_{4\mathrm{eq}}^{3-}/{\mathrm{m}}^3$) $\mathrm{COD}$•, chemical oxygen demand in water discharges (mg/L) ${\mathrm{COD}}_t$•, threshold of the average chemical oxygen demand in water discharges (mg/L) $\mathrm{TN}$•, total nitrogen concentration in water discharges (mg/L) ${\mathrm{TN}}_t$•, threshold of the average total nitrogen concentration in water discharges (mg/L)
nBCR: Normalized benefit–cost ratio	$\mathrm{nBCR}={\mathrm{BCR}}^{\ast }=\frac{1}{\mathrm{BCR}}$ $\mathrm{BCR}=\frac{{\sum }_{i=0}^T\frac{B_i}{{\left(1,+,r\right)}^i}}{{\sum }_{i=0}^T\frac{C_t}{{\left(1,+,r\right)}^i}}$	(6)	•BCR*, normalized benefit–cost ratio (—) •BCR, benefit–cost ratio (—) $B_i$•, benefits of the project in the ith period ($) $C_i$•, costs of the project in the ith period ($) •r, real discount rate (%) •i, time period of analysis (year) •T, total number of analyzed periods (years)
nEROI: Normalized energy return on investment	$\mathrm{nEROI}={\mathrm{EROI}}^{\ast }=\frac{{\mathrm{EROI}}_t}{\mathrm{EROI}}$ $\mathrm{EROI}=\frac{E_b}{E_d}$	(7)	${\mathrm{EROI}}^{\ast }$•, normalized EROI (—) ${\mathrm{EROI}}_t$•, threshold value of the EROI for renewable energy (= 3.0) [27] $\mathrm{EROI}$•, Energy return on investment of the bioenergy system (—) $E_b$•, energy generated in the bioenergy system (MW) $E_d$•, life cycle cumulative energy demand of the bioenergy system (MW)
nFER: Normalized fossil energy ratio	$\mathrm{nFER}={\mathrm{FER}}^{\ast }=\frac{{\mathrm{FER}}_t}{\mathrm{FER}}$ $\mathrm{FER}=\frac{E_b}{E_{d,f}}$	(8)	${\mathrm{FER}}^{\ast }$•, normalized FER (—) ${\mathrm{FER}}_t$•, threshold value of the FER for renewable energy (= 5.0) [28] $\mathrm{FER}$•, fossil energy ratio of the bioenergy system (—) $E_b$•, energy generated by the bioenergy system (MW) $E_{d,f}$•, life cycle cumulative fossil-energy demand of the bioenergy system (MW)
EDIR: Direct employment	$\mathrm{EDIR}={\mathrm{DE}}^{\ast }=\frac{{\mathrm{DE}}_t}{\mathrm{DE}}$ $\mathrm{DE}=\frac{\mathrm{WT}}{E_b^1}$	(9)	${\mathrm{DE}}^{\ast }$•, normalized direct employment (—) ${\mathrm{DE}}_t$•, threshold value, corresponding to the worker time per unit of energy produced in the reference system (electricity from natural gas) (worker-year/GJ) $\mathrm{DE}$•, direct worker time per unit of energy produced (worker-year/GJ) ${\mathrm{WT}}^{\prime }$•, worker-time directly involved in the activities of biomass procuring, maintenance and operation of the bioenergy generating system (worker-year) $E_b^{\prime }$•, energy generated by the bioenergy system, measured before distribution and end-use (GJ)
EGEN: Gender equality among employees	$\mathrm{EGEN}={\mathrm{GE}}^{\ast }=\frac{(50-\mathrm{GE})\bullet {\mathrm{GE}}_t}{(50-{\mathrm{GE}}_t)\bullet \mathrm{GE}}$ $\mathrm{GE}=\frac{\min \left(W_M,,,W_W\right)}{W_M+W_F}\times 100$	(10)	${\mathrm{GE}}^{\ast }$•, normalized gender equality among workers (—) $\mathrm{GE}$•, percentage of direct workers in the bioenergy system of the least represented gender [%] ${\mathrm{GE}}_t$•, threshold value for the percentage of workers of the least represented gender (%) $W_M$•, number of male workers directly involved in the bioenergy system (—) $W_W$•, number of female workers directly involved in the bioenergy system (—) •The number 50 refers to the ideal value of $\mathrm{GE}$ (50%)
EFORM: Formal employment	$\mathrm{EFORM}={\mathrm{FE}}^{\ast }=\frac{(100-\mathrm{FE})\bullet {\mathrm{FE}}_t}{(100-{\mathrm{FE}}_t)\bullet \mathrm{FE}}$	(11)	${\mathrm{FE}}^{\ast }$•, normalized formal employment (—) •FE, percentage of direct workers in the bioenergy system having formal employment (social security) (%) ${\mathrm{FE}}_t$•, threshold of the percentage of workers having formal employment (social security) (%) •The number 100 refers to the ideal value of $\mathrm{FE}$ (100%)
EDU: Educational level of workers	$\mathrm{EDU}={\mathrm{EL}}^{\ast }=\frac{(100-\mathrm{EL})\bullet {\mathrm{EL}}_t}{(100-{\mathrm{EL}}_t)\bullet \mathrm{EL}}$	(12)	${\mathrm{EL}}^{\ast }$•, normalized educational level of workers (—) $\mathrm{EL}$•, percentage of direct workers in the bioenergy system that completed the compulsory education level (%) ${\mathrm{EL}}_t$•, threshold of the percentage of workers that completed the compulsory education (%) •The number 100 refers to the ideal value of $\mathrm{EL}$ (100%)
EARN: Average earnings per capita	$\mathrm{EARN}={\mathrm{AE}}^{\ast }=\frac{{\mathrm{AE}}_t}{\mathrm{AE}}$ $\mathrm{AE}=\frac{1}{12\bullet W_r}{\sum }_{i=1}^{W_r}{\mathrm{AE}}_i$	(13)	${\mathrm{AE}}^{\ast }$•, normalized average earnings per capita (—) $\mathrm{AE}$•, average earnings per capita of the direct rural workers in the biorefinery system ($/month/worker) ${\mathrm{AE}}_t$•, poverty threshold defined for the rural population in Mexico ($/month/worker) $W_r$•, number of direct rural workers directly involved in the bioenergy system (—) ${\mathrm{AE}}_i$•, average annual earnings of the $i\mathrm{th}$ worker ($/a)