Decreasing the Environmental Impact in an Egg-Producing Farm Through the Application of LCA and Lean Tools

applied sciences

Article Decreasing the Environmental Impact in an Egg-Producing Farm through the Application of LCA and Lean Tools

Iván E. Estrada-González 1, Paul Adolfo Taboada-González 2 , Hilda Guerrero-García-Rojas 3 and Liliana Márquez-Benavides 4,*

1 Faculty of Biology, Building “R”, Ground Floor, University Campus, UMSNH, 58000 Morelia, Michoacán, Mexico; [email protected] 2 Facultad de Ciencias Químicas e Ingeniería, Universidad Autónoma de Baja California, Calzada Universidad No. 14418, Mesa de Otay, 22390 Tijuana, Mexico; [email protected] 3 Faculty of Economy “Vasco de Quiroga”, Building “T2”, Upper Floor, University Campus, UMSNH, 58000 Morelia, Michoacán, Mexico; [email protected] 4 Institute of Agricultural and Forestry Research (IIAF)-UMSNH, San Juanito Itzícuaro Avenue, C.P. 58341 San Juanito Itzícuaro, Morelia, Michoacán, Mexico * Correspondence: [email protected]

Received: 18 January 2020; Accepted: 12 February 2020; Published: 17 February 2020

Abstract: Intensive poultry farming transforms vegetable protein into animal protein through shelf egg and chicken meat production. Mexico is the largest egg consumer and fifth-ranked egg producer worldwide. However, the environmental impact of egg production in this country is scarcely reported. This research aimed to design an eco-efficient approach for egg production in a semi-technified farm based on door-to-door life cycle assessment (LCA) and value stream mapping (VSM) methodologies. The LCA points out that the climate change category is a hotspot in egg production, with emissions of 5.58 kg CO2 eq/kg per egg produced. The implementation of an eco-efficient scheme focused on energy usage could result in a 49.5% reduction of total energy consumption and 56.3% saving in environmental impacts. Likewise, by using an environmental economic evaluation system, it is identified that the eco-efficient scheme allows more sustainable production through the internalization of externalities. From an environmental–economic point of view, externalities—that is, those environmental damages that are not initially considered part of the production cost—were included, meaning they were internalized. The integral framework for LCA and VSM provides a possible path for sustainable productivity.

Keywords: life cycle assessment; value stream mapping; egg production; eco-eﬃciency

1. Introduction Facing environmental degradation and a decrease in resources, eco-efficiency has been proposed as one of the main tools to promote sustainable development. Eco-efficiency means that a system provides an affordable service while satisfying human needs and reducing the intensity of consumption of inputs and environmental impacts [1]. Consumers are looking for better quality products through environmentally friendly production. Thus, producers are obliged to increase or maintain a level of production while reducing their environmental impact, without compromising either the quality of performance of their processes [2,3]. Animal husbandry is one of the production processes necessary for world food security [4]; dairy farming, meat poultry, and aquaculture are the most representative. These processes are the world’s primary industries that transforms vegetable protein into animal protein. This production process

Appl. Sci. 2020, 10, 1352; doi:10.3390/app10041352 www.mdpi.com/journal/applsci Appl. Sci. 2020, 10, 1352 2 of 14 maintains an intensive specialized egg production sector, which consists of separating chicken meat and shelf egg production. The hatching egg sector is not taken into account in this work. Shelf egg production demands food and water inputs due to the biological need for birds and environmental conditions [5,6]. The energy consumption is a consequence of the farm operations and their level of automation. It has been reported that the most energy-demanding processes in the poultry industry are climate control and lighting, with variable energy consumption of 3 to 4.4 kWh/bird/m2/year [7]. The analysis of egg production is gaining importance, which is why studies have been carried out in countries such as Germany, Australia, Canada, the United Kingdom, and Switzerland to create a history of the consumption of energy inputs and materials to estimate the carbon footprint for each kilogram of egg produced according to its housing system (Table1).

Table 1. Carbon footprint in egg production according to the poultry housing system.

Place Accommodation System GHG (kg CO2-eq/kg Egg) References Australia Controlled cage 1.3 +/ 0.2 [8] − Cage 1.4 Switzerland [9,10] Cage (includes packaging) 1.6–1.8 Canada Cage 2.5 [11] Cage 3.9 England [12] Barnyard 4.6 Cage 5.25 United Kingdom [13] Barnyard 6.18 Australia Barnyard 1.6 +/ 0.3 [8] − Germany Barnyard 4 [14]

Mexico is the world’s leading egg consumer, with an estimated annual per capita consumption of 23.3 kg [15]. There is a high demand in the national diet, so the poultry sector has considerable participation in the production of shelf eggs and gross domestic product (GDP). In 2018, the poultry sector represented 63.3% of the country’s agricultural activities, of which 28.2% corresponded to the generation of egg products. According to the Mexican National Union of Poultry Producers [15], shelf egg production in 2019 reached 2.88 106 t. Expectations for growth in this field are 1.45% per × annum [16,17]. Despite the importance of shelf egg production in Mexico, as it represents 17% of the protein contribution by the livestock sector, there is no national data reporting on environmental assessments. As part of the contribution to food sovereignty, the aim is for agricultural production to be carried out under eco-efficient production schemes. Therefore, it is essential to identify significant environmental issues and opportunities for improvement in this sector. There are tools such as life cycle assessment (LCA) that allow us to estimate potential environmental impacts within a supply chain, and that can integrate improvement strategies into the process [18]. Globally, LCA has been applied to the study of egg production, considering inputs such as diets, electricity, water expenditure, and land-use change [14]. Value stream mapping (VSM) is one of the techniques that can be integrated into LCA. This tool allows visualization of the flow of information in terms of the unitary productivity, efficiency, and reduction of process wastage [19,20]. The solution obtained through the integration of these instruments reduces waste by 20%–50%, understood as being due to reducing problems in the supply chains of a process [21]. For example, [20] reported a 25% decrease in material consumption, 19% decrease in energy consumption, and 7% decrease in the carbon footprint of an automotive production line in India. To the best of the author’s knowledge, there are no reports on the integration of LCA and VSM for shelf egg production. There is a lack of studies on eco-efficient scenarios that integrate the environmental impacts derived from inefficiency into the use of inputs. This study aimed to design an eco-efficient scheme for a semi-technified poultry farm. Appl. Sci. 2020, 10, 1352 3 of 14 Appl. Sci. 2020, 10, x FOR PEER REVIEW 3 of 14 Appl. Sci. 2020, 10, x FOR PEER REVIEW 3 of 14 LCA and VSM methodologies were integrated into this work to design a tailor-made eco- 2. MethodologyLCA and VSM methodologies were integrated into this work to design a tailor-made eco- efficient scheme for egg production. LCA was applied to determine the potential for environmental efficient scheme for egg production. LCA was applied to determine the potential for environmental contributionLCA and through VSM methodologies 18 impact categories were integrated for each into production this work stage. to design The aVSM, tailor-made on the other eco-effi hand,cient contribution through 18 impact categories for each production stage. The VSM, on the other hand, madescheme it forpossible egg production. to identify LCAopportunities was applied in tothe determine system. The the work potential plan for for environmental this research contributionis shown in made it possible to identify opportunities in the system. The work plan for this research is shown in Figurethrough 1. 18 impact categories for each production stage. The VSM, on the other hand, made it possible toFigure identify 1. opportunities in the system. The work plan for this research is shown in Figure1.

FigureFigure 1. Work planplan forfor the the design design of of an an eco-e eco-efficientﬃcient scheme scheme in the in productionthe production of eggs of eggs in Mexico. in Mexico. Note: Figure 1. Work plan for the design of an eco-efficient scheme in the production of eggs in Mexico. Note:LCA, LCA, life cycle life assessment;cycle assessment; VSM, VSM, value value stream stream mapping. mapping. Note: LCA, life cycle assessment; VSM, value stream mapping. 2.1.2.1. Life Life Cycle Cycle Assessment Assessment 2.1. Life Cycle Assessment ThisThis methodology is is oriented oriented to to the evaluation of the environmental impacts of of products and This methodology is oriented to the evaluation of the environmental impacts of products and services.services. It has fourfour phasesphases according according to to ISO ISO 14040:2006 14040:2006 (Figure (Figure2), in2), whichin which objectives objectives and and scopes scopes that services. It has four phases according to ISO 14040:2006 (Figure 2), in which objectives and scopes thatdeﬁne define inputs inputs and and outputs outputs of a systemof a system product product are limited. are limited. that define inputs and outputs of a system product are limited.

FigureFigure 2. 2. LifeLife cycle cycle analysis analysis framework framework of of reference reference [22]. [22]. Figure 2. Life cycle analysis framework of reference [22]. 2.1.1. Description of the System and Area of Study 2.1.1. Description of the System and Area of Study 2.1.1. Description of the System and Area of Study The study of shelf egg production for the present work was conducted on a semi-technified The study of shelf egg production for the present work was conducted on a semi-technified farm, farm,The located study in of Tepatitl shelf eggán deproduction Morelos, Jalisco,for the present Mexico, work known was as conducted “Laguna Colorada on a semi-technified”; (20 45 48.811” farm, N; located in Tepatitlán de Morelos, Jalisco, Mexico, known as “Laguna Colorada”; (20°45◦ ′48.8110 ′′ N; 102located49 47.504” in Tepatitlán O). The de location Morelos, has Jalisco, an average Mexico, elevation known of as 1880 “Laguna m above Colorada sea level”; (20°45 and′48.811 an annual′′ N; 102°49◦ ′047.504′′ O). The location has an average elevation of 1880 m above sea level and an annual average102°49′47.504 temperature′′ O). The of 19.1locationC. Inhas Mexico, an average there areelevation three di offf erent1880 productionm above sea systems, level and characterized an annual average temperature of 19.1 °C.◦ In Mexico, there are three different production systems, characterized byaverage their temperature technological of level:19.1 °C. (i) In technified,Mexico, there (ii) ar semi-technical,e three different andproduction (iii) backyard systems, systems. characterized The by their technological level: (i) technified, (ii) semi-technical, and (iii) backyard systems. The dibyff erencestheir technological between these level: systems (i) aretechnified, due to the (ii) technology semi-technical, that is handled.and (iii) A backyard technified systems. farm is firstly The differences between these systems are due to the technology that is handled. A technified farm is characterizeddifferences between by high these technology systems and are automated due to the processes technology that that allow is handled. handling A of technified large numbers farm ofis firstly characterized by high technology and automated processes that allow handling of large animalsfirstly characterized and a reduction by of high costs, technology depending and on the automated volume of processes production; that and allow secondly handling by the formsof large of numbers of animals and a reduction of costs, depending on the volume of production; and secondly dispositionnumbers of ofanimals credit orand risk a reduction capital and of integration costs, depen ofding social on capital. the volume The technified of production; and semi-technical and secondly by the forms of disposition of credit or risk capital and integration of social capital. The technified schemesby the forms make of use disposition of the maximum of credit possibleor risk capital efficiency and integration of the food of conversion social capital. index, The so technified that they and semi-technical schemes make use of the maximum possible efficiency of the food conversion and semi-technical schemes make use of the maximum possible efficiency of the food conversion index, so that they produce more efficient food and conditions for production, with rigid sanitary index, so that they produce more efficient food and conditions for production, with rigid sanitary Appl. Sci. 2020, 10, 1352 4 of 14 Appl. Sci. 2020, 10, x FOR PEER REVIEW 4 of 14 producecontrols more[23]. In effi thecient studied food and farm, conditions only two for pa production,rts of the process with rigid were sanitary automated controls (breeding [23]. In and the studiedposture farm,phases). only The two laying parts ofphase the process was handled were automated manually (breedingby farmworkers. and posture The phases).chicken Thebreed laying was 2 phaseHy-Line was W-36 handled and a manually battery cage by farmworkers. system (450 cm The, or chicken three birds/cage) breed was Hy-Linewas used W-36 to house and a96,000 battery 1- cageday old system chicks (450 per cm poultry2, or three house. birds Adult/cage) laying was used hens to were house accommodated 96,000 1-day old in chicks three perpoultry poultry houses. house. AdultThe laying poultry hens houses were accommodated at the studied infarm three have poultry dimensions houses. measuring 10 m × 3 m × 100 m and a controlledThe poultry environment houses (31.46 at the °C studied for breeding, farm have 20.81 dimensions °C for laying, measuring and 21.92 10 °C m for3 posture; m 100 humidity m and a = 50% with forced ventilation). A total of 917 incandescent bulbs were used per× poultry× house to controlled environment (31.46 ◦C for breeding, 20.81 ◦C for laying, and 21.92 ◦C for posture; humidity = 50%provide with 15 forced lux (laying ventilation). hens Arequire total ofillumination 917 incandescent for 16–17 bulbs h/day). were used The pereggs poultry are manually house to collected provide 15and lux packed (laying in hens cardboard require boxes illumination containing for 16–17360 eggs. h/day). Waste, The such eggs as are manure manually and collected bird carcasses, and packed were inmanually cardboard removed boxes containingfrom the poultry 360 eggs. houses Waste, and such co asmposted. manure The and obtained bird carcasses, data of were the manuallylife cycle removedinventory from correspond the poultry to the houses summer and of composted. 2016. The system The obtained at this datafarm of is theintensive life cycle for inventoryshelf egg correspondproduction. to the summer of 2016. The system at this farm is intensive for shelf egg production.

2.1.2.2.1.2. Functional UnitUnit andand ReferenceReference FlowFlow TheThe functionalfunctional unitunit waswas aa kilogramkilogram ofof eggegg productionproduction onon aa semi-techniﬁedsemi-technified farm.farm. AA referencereference ﬂowflow ofof 1,800,0001,800,000 kgkg forfor eggegg productionproduction waswas presentedpresented forfor aa totaltotal productionproduction periodperiod ofof 7676 weeksweeks (June(June 2016–February2016–February 2017).2017).

2.1.3.2.1.3. System LimitsLimits TheThe system product was was limited limited to to the the stages stages of of chick chick breeding breeding (6 (6weeks), weeks), bird bird development development (10 (10weeks), weeks), egg egglaying laying (60 (60weeks), weeks), and and egg egg product product packaging. packaging. Figure Figure 3 represents3 represents the the limits limits of ofthe thesystem. system.

FigureFigure 3.3. Limits of the system productproduct inin thethe valuationvaluation ofof environmentalenvironmental impactsimpacts byby LCA.LCA. 2.1.4. Data Sources and Life Cycle Impact Assessment to Obtain Environmental Dimension Metrics 2.1.4. Data Sources and Life Cycle Impact Assessment to Obtain Environmental Dimension Metrics According to the limits of the system, both material and energy input data were obtained directly According to the limits of the system, both material and energy input data were obtained directly from the egg production poultry farm. For the environmental impact analysis, Ecoinvent 3.4 and from the egg production poultry farm. For the environmental impact analysis, Ecoinvent 3.4 and Agri-footprint databases in SimaPro software, version 8.5, were used. The evaluation was carried Agri-footprint databases in SimaPro software, version 8.5, were used. The evaluation was carried out out using the method “ReCiPe Midpoint V 1.13/World ReCiPe H”, which considers 18 midpoint using the method “ReCiPe Midpoint V 1.13/World ReCiPe H”, which considers 18 midpoint impact impact categories (Table2). The most significant categories of impact on egg production were categories (Table 2). The most significant categories of impact on egg production were selected selected (Section 3.1). Subsequently, a second impact assessment was carried out considering only the (Section 3.1). Subsequently, a second impact assessment was carried out considering only the energy energy demand of the system (Figure1). The results obtained in both cases were the metrics for the demand of the system (Figure 1). The results obtained in both cases were the metrics for the environmental impact assessment. environmental impact assessment. Table 2. Middle-point impact categories. Table 2. Middle-point impact categories. Category Impacts Indicator Unit Category Impacts Indicator Unit Radioactive forcing as global warming Radioactive forcing as global warming kg carbon dioxide-eq (CO -eq) 1. Climate change kg carbon dioxide-eq (CO2-eq)2 potentialpotential kg trichlorofluoromethane-eqkg trichlorofluoromethane-eq (CFC-11- 2. Ozone depletion OzoneOzone depletion depletion potential potential (CFC-11-eq)eq) 3. Terrestrial acidification Accumulated exceedance kg sulphur dioxide-eq (SO2-eq) 3. Terrestrial acidification Fraction ofAccumulated nutrients reaching exceedance freshwater kg sulphur dioxide-eq (SO2-eq) 4. Freshwater eutrophication kg phosphor-eq (P-eq) end compartment Fraction of nutrients reaching marine end 5. Marine eutrophication kg nitrogen-eq (N-eq) compartment 6. Human toxicity Comparative toxic unit for humans kg 1,4 dichlorobenzene-eq (1,4-DB-eq) Appl. Sci. 2020, 10, 1352 5 of 14

Table 2. Cont.

Category Impacts Indicator Unit Fraction of nutrients reaching freshwater end 4. Freshwater eutrophication kg phosphor-eq (P-eq) compartment Fraction of nutrients reaching marine end 5. Marine eutrophication kg nitrogen-eq (N-eq) compartment kg 1,4 dichlorobenzene-eq 6. Human toxicity Comparative toxic unit for humans (1,4-DB-eq)

7. Photochemical kg non-methane volatile organic Tropospheric ozone concentration increase oxidant formation compounds (NMVOC)

kg particulate matter 10-eq 8. Particulate matter formation Impact on human health (PM10-eq) kg 1,4 dichlorobenzene-eq 9. Terrestrial ecotoxicity Comparative toxic unit for ecosystems (1,4-DB-eq) kg 1,4 dichlorobenzene-eq 10. Freshwater ecotoxicity Comparative toxic unit for ecosystems (1,4-DB-eq) kg 1,4 dichlorobenzene-eq 11. Marine ecotoxicity Comparative toxic unit for ecosystems (1,4-DB-eq) kg 1,4 dichlorobenzene-eq 12. Ionising radiation Human exposure eﬃciency relative to U235 (1,4-DB-eq)

13. Agricultural land occupation m2a, area Soil quality index, biotic production Erosion 14. Urban land transformation resistance, mechanical ﬁltration Ground m2a, area water replenishment 15. Natural land transformation m2

User deprivation potential 16. Water depletion m3, volume (deprivation-weighted water consumption)

17. Metal depletion Abiotic resource depletion kg iron-eq (Fe-eq)

18. Fossil depletion Abiotic resource depletion—fossil fuels kg oil-eq

2.1.5. Input Data of the LCA Limits The data inventory was obtained directly from the poultry farm through surveys. Table3 contains the database of material inventory for egg production phases. Two products were obtained as residues, bird carcasses, and manure; both were composted. Table4 contains the fuel inventory database for the studied poultry farm.

Table 3. Material inventory database from poultry farm per production phase.

Breeding Phase Inputs from technosphere Amount Unit Description Compound feed broilers/NL Mass MX Lq 30,240 kg Grain Tap water {RoW} tap water production, conventional 60,322 kg Water treatment | Alloc Def, U One-day-chickens. At hatchery/NL Mass Lq 94,752 piece Chicks Outputs to technopshere Amount Unit Description Biowaste {MX} treatment of, composting | Alloc Def, U 561.6 kg Bird carcasses Poultry manure, fresh {ROW}| market for | Alloc Def, U 102.9 kg Manure Appl. Sci. 2020, 10, 1352 6 of 14

Table 3. Cont.

Development Phase Inputs from technosphere Amount Unit Description Compound feed broilers/NL Mass MX Lq 282,240 kg Grain Tap water {RoW} tap water production, conventional 564,480 kg Water treatment | Alloc Def, U Laying hens < 17 weeks, breeding, at farm/NL Mass MX Lq 94,657 Piece Bird Outputs to technopshere Amount Unit Description Biowaste {MX} treatment of, composting | Alloc Def, U 128.2 kg Bird carcasses Poultry manure, fresh {ROW}| market for | Alloc Def, U 514.3 kg Manure Egg posture Phase Inputs from technosphere Amount Unit Description Compound feed broilers/NL Mass MX Lq 3362.3 kg Grain Tap water {RoW} tap water production, conventional 7,301,700 kg Water treatment | Alloc Def, U Laying hens > 17 weeks, breeding, at farm/NL Mass MX Lq 94,184 Piece Birds Outputs to technopshere Amount Unit Description Biowaste {MX} treatment of, composting | Alloc Def, U 756.8 kg Bird carcasses Poultry manure, fresh {ROW}| market for | Alloc Def, U 4549.1 kg Manure Package Phase Inputs from technosphere Amount Unit Description Linerboard board box production, with gravure printing 360 cardboard {ROW} carton board production servidem with gravure 39,375 kg egg boxes printing | Alloc Def, U Dozen Linerboard {ROW} | production, kraftliner | Alloc Def, U 63,455 kg linerboard egg box

Table 4. Fuel inventory database from poultry farm per production phase.

Breeding Phase Inputs from Technosphere Amount Unit Operation 582.7 kWh Illumination Electricity, medium voltage {MX} electricity voltage 2960.9 kWh Air extraction transformation from high to medium voltage | Alloc Def, U 107.4 kWh Water pump 62.6 kWh Food supplying Liqueﬁed petroleum gas {RoW} petroleum reﬁnery 2.80 kg Heating operation | Alloc Def, U Development Phase Electricity, medium voltage {MX} electricity voltage 272.1 kWh Illumination transformation from high to medium voltage | Alloc Def, U 537.1 kWh Water pump Egg Posture Phase 5443.2 kWh Illumination Electricity, medium voltage {MX} electricity voltage 3222.7 kWh Water pump transformation from high to medium voltage | Alloc Def, U 1418.9 kWh Food Supplying Alloc Def, U = Allocation, default unit; NL Mass MX Lq = Netherland mass, Mexico adaptation (Agri-footprint). Appl. Sci. 2020, 10, x FOR PEER REVIEW 6 of 14 Appl. Sci. 2020, 10, x FOR PEER REVIEW 6 of 14 Table 4. Fuel inventory database from poultry farm per production phase. Table 4. Fuel inventory databaseBreeding from poultryPhase farm per production phase. Inputs from Technosphere Breeding Phase Amount Unit Operation Inputs from Technosphere Amount582.7 UnitkWh Illumination Operation Electricity, medium voltage {MX} electricity voltage 2960.9582.7 kWhkWh AirIllumination extraction transformationElectricity, medium from high voltag to mediume {MX} electricityvoltage | Alloc voltage Def, U 2960.9107.4 kWhkWh AirWater extraction pump transformation from high to medium voltage | Alloc Def, U 107.462.6 kWhkWh FoodWater supplying pump Liquefied petroleum gas {RoW} petroleum refinery operation | 62.62.80 kWhkg Food Heating supplying Liquefied petroleum gas {RoW}Alloc Def, petroleum U refinery operation | 2.80 kg Heating Alloc Def, U Development Phase Electricity, medium voltage {MX} electricity Developmentvoltage Phase 272.1 kWh Illumination transformationElectricity, medium from high voltag to mediume {MX} electricityvoltage | Alloc voltage Def, U 272.1537.1 kWhkWh IlluminationWater pump transformation from high to medium voltage | AllocEgg Def, Posture U Phase 537.1 kWh Water pump 5443.2 kWh Illumination Electricity, medium voltage {MX} electricity voltageEgg Posture Phase 5443.23222.7 kWhkWh IlluminationWater pump transformationElectricity, medium from high voltag to mediume {MX} electricityvoltage | Alloc voltage Def, U 3222.71418.9 kWhkWh FoodWater Supplying pump transformation from high to medium voltage | Alloc Def, U 1418.9 kWh Food Supplying Appl. Sci.Alloc2020 Def,, 10 U, 1352= Allocation, default unit; NL Mass MX Lq = Netherland mass, Mexico adaptation (Agri-footprint). 7 of 14 Alloc Def, U = Allocation, default unit; NL Mass MX Lq = Netherland mass, Mexico adaptation (Agri-footprint). 2.2. Value Stream Mapping 2.2. Value Value Stream Mapping The primary function of this tool is to map activities with or without added value necessary to elaborateThe primary a family function of products of this (or tool just one),is to mapfollowi activitiesactingvities the process with or of without a product added from value the raw necessary material to elaborateto its completion a familyfamily or ofof delivery productsproducts to (or(or the just just client one), one), [19,24] following followi (Figureng the the process4). process of of a a product product from from the the raw raw material material to toits its completion completion or or delivery delivery to theto the client client [19 [19,24],24] (Figure (Figure4). 4).

Figure 4. Product system VSM frame of reference [24]). Figure 4. Product system VSM frame of reference [24]). Figure 4. Product system VSM frame of reference [24]). The shelf egg is the product of interest and is obtained within 76 weeks of the system product The shelf egg is the product of interest and is obtained within 76 weeks of the system product process.The Atshelf the egg end is of the the product production of interest cycle, and a quan is obtainedtity of 1,800,000 within 76kg weeks of eggs of were the system produced. product The process. At the end of the production cycle, a quantity of 1,800,000 kg of eggs were produced. The process.VSM was At limitedthe end toof thethe productiondemand for cycle, inputs a quan fromtity theof 1,800,000chick breeding kg of eggs stages were (6 produced. weeks), birdThe VSM was limited to the demand for inputs from the chick breeding stages (6 weeks), bird development VSMdevelopment was limited (10 weeks), to the and demand egg posture for inputs of layi ngfrom hens the (60 chick weeks) breeding within thestages study (6 farm. weeks), bird (10 weeks), and egg posture of laying hens (60 weeks) within the study farm. developmentData from (10 the weeks), LCA andinventory egg posture of energy of layi inputsng hens and (60 materials weeks) werewithin used. the study Data farm.were classified Data from the LCA inventory of energy inputs and materials were used. Data were classiﬁed accordingData fromto the the equipment LCA inventory used, and of energy the inputs inputs of LCAand materials tools together were withused. VSM Data were were developed classified according to the equipment used, and the inputs of LCA tools together with VSM were developed accordingthrough a tofour the part equipment follow up used, (Figure and 5). the inputs of LCA tools together with VSM were developed through a four part follow up (Figure5). through a four part follow up (Figure 5).

Figure 5. Monitoring of the VSM development stages of the current study. Figure 5. Monitoring of the VSM development stages of the current study. The equipmentFigure used 5. Monitoring in shelf egg of productionthe VSM developmen was classifiedt stages accordingof the current to thestudy. unit operation and The equipment used in shelf egg production was classified according to the unit operation and corresponding stage. The standard energy consumption was calculated using shelf egg data. After, correspondingThe equipment stage. used The instandard shelf egg energy production consumpt wasion classified was calculated according using to the shelf unit egg operation data. After, and with the energy data, an energy flow map (EFM) was developed, presenting the total and partial correspondingwith the energy stage. data, The an standardenergy flow energy map consumpt (EFM) wasion developed, was calculated presenting using shelf the totalegg data.and partialAfter, energy expenditure of each stage of the process. Using Equations (1) and (2), the specific energy and withenergy the expenditure energy data, of aneach energy stage flowof the map process. (EFM) Us ingwas Equations developed, (1) presenting and (2), the the specific total andenergy partial and energy productivity per kilogram of the produced egg was calculated. energyenergy expenditureproductivity of per each kilogram stage of of the the process. produced Us egging Equationswas calculated. (1) and (2), the specific energy and energy productivity per kilogram of the produced Energyegg was use calculated.(kWh) Speci f ic energy = (1) Egg production (kg)

Egg production (kg) Energy productivity = (2) Energy use (kWh) An on-site analysis was carried out, where the equipment plate data were reviewed and the information from the equipment manufacturers was consulted. The pieces of equipment with the highest energy consumption at the farm were identified to propose more efficient alternatives. Energy billing concepts (energy consumption, power factor, demand factor) were also considered as relevant data in decision making for the eco-efficient scheme. Once the improvement opportunities for the process had been identified, a flow map was drawn up to measure future value with an eco-efficient approach, using as a metric the substitution of a certain technology for one with greater energy efficiency. Finally, this was compared with the current scenario of the process only in the category of climate change. Appl. Sci. 2020, 10, x FOR PEER REVIEW 7 of 14

𝐸𝑛𝑒𝑟𝑔𝑦 𝑢𝑠𝑒𝑘𝑊ℎ 𝑆𝑝𝑒𝑐𝑖𝑓𝑖𝑐 𝑒𝑛𝑒𝑟𝑔𝑦 (1) 𝐸𝑔𝑔 𝑝𝑟𝑜𝑑𝑢𝑐𝑡𝑖𝑜𝑛 𝑘𝑔 𝐸𝑔𝑔 𝑝𝑟𝑜𝑑𝑢𝑐𝑡𝑖𝑜𝑛 𝑘𝑔 𝐸𝑛𝑒𝑟𝑔𝑦 𝑝𝑟𝑜𝑑𝑢𝑐𝑡𝑖𝑣𝑖𝑡𝑦 (2) 𝐸𝑛𝑒𝑟𝑔𝑦 𝑢𝑠𝑒 𝑘𝑊ℎ An on-site analysis was carried out, where the equipment plate data were reviewed and the information from the equipment manufacturers was consulted. The pieces of equipment with the highest energy consumption at the farm were identified to propose more efficient alternatives. Energy billing concepts (energy consumption, power factor, demand factor) were also considered as relevant data in decision making for the eco-efficient scheme. Once the improvement opportunities for the process had been identified, a flow map was drawn up to measure future value with an eco-efficient approach, using as a metric the substitution of a certain technology for one with greater energy efficiency. Finally, this was compared with the current Appl. Sci. 2020, 10, 1352 8 of 14 scenario of the process only in the category of climate change.

3.3. Results TheThe estimatedestimated environmentalenvironmental impactimpact profileprofile correspondscorresponds toto aa semi-technifiedsemi-technified poultrypoultry farmfarm withwith anan intensive production production system. system. Laying Laying hen hen manage management,ment, productivity productivity (egg/day), (egg/day), and mortality and mortality rates rateswere werestandard standard according according to the to themanagement management guide guide for for Hy-Line Hy-Line W-36 W-36 hens hens [15]. [15]. This This breed isis advertisedadvertised asas thethe mostmost eefficiefficientnt layinglaying breedbreed worldwide.worldwide.

3.1.3.1. Life Cycle AnalysisAnalysis WithinWithin thethe limitslimits ofof thethe systemsystem (Section(Section 2.1.32.1.3),), thethe environmentalenvironmental impactimpact assessmentassessment ofof shelfshelf eggegg productionproduction showsshows thatthat thethe eggegg layinglaying stagestage accountedaccounted forfor 79%79% ofof thethe environmentalenvironmental impactimpact ofof thethe productproduct (Figure(Figure6 6).). OfOf 18 18 middle-point middle-point impactimpact categoriescategories (Table(Table2 ),2), 10 10 were were identified identified as as significant significant andand representrepresent atat least least 75% 75% of of the the contribution contribution in in each each category category (Table (Table5). 5). Of Of 10 identified10 identified categories categories in thein the egg-laying egg-laying phase, phase, seven seven are relatedare related to broiler to broile compoundr compound feed. feed. Therefore, Therefore, this last this one last is one the inputis the withinput the with largest the largest number number of impact of impact categories. categories Other. Other reports reports about about egg productionegg production also also identify identify the compoundthe compound feed feed as the as inputthe input with with the mostthe most significant significant contribution contribution of environmental of environmental impact impact in the in entirethe entire system system product product [25]. [25].

FigureFigure 6.6. Potential environmental impactimpact inin thethe eggegg productionproduction phases.phases. Table 5. Signiﬁcant impact categories for egg posture phase and total shelf egg production process (per kilogram).

Egg Posture LCA Inventory Impact Category Symbol Input Total, Process Phase

Climate change CC 4.4 kg CO2-eq 5.6 kg CO2-eq Water depletion AA 6.3 10 2 m3 7.8 10 2 m3 × − × − 1.4 10 1 kg 1.6 10 1 kg Human toxicity TH × − × − 1,4-DB-eq 1,4-DB-eq Compound feed broilers/NL Mass Fresh water 5.3 10 4 kg 6.5 10 4 kg EAF Food × − × − MX Lq eutrophication P-eq P-eq 6.6 10 2 kg 8.5 10 2 kg Terrestrial ecotoxicity ECT × − × − 1,4-DB- 1,4-DB-eq 2.2 10 2 kg 2.7 10 2 kg Fresh water ecotoxicity ECAF × − × − 1,4-DB-eq 1,4-DB-eq Agriculture land use USA 4.2 m2a 5.2 m2a Laying hens > 17 weeks, breeding, Particulate material 7.5 10 3 kg 1.1 10 2 kg FMP Birds × − × − at farm/NL Mass MX Lq formation PM10-eq PM10-eq Fossil resources 7.4 10 1 kg 9.4 10 1 kg Electricity, medium voltage {MX} AF − − Electricity × × electricity voltage transformation depletion crude oil-eq crude oil-eq 2.7 10 7 kg 3.6 10 7 kg from high to medium voltage | Alloc Ozone depletion AO × − × − Def, U CFC-11-eq CFC-11-eq

Electricity is an input that can be modiﬁed by reducing its use in the process without compromising the bird’s biology, unlike diet. Table6 shows the environmental contribution derived from the use of electricity and fuel in the stages of the egg production process (kWh/kg egg). Appl. Sci. 2020, 10, 1352 9 of 14

Table 6. Potential impacts of egg production related to the use of process electricity.

Current Process Scenario Impact Category Process Stage Total Impact Breeding Development Posture Potential per Contribution kWh/kg Egg 3 4 3 3 Climate change (kg CO2 eq) 1.31 10 2.85 10 3.55 10 5.14 10 × − × − × − × − Human toxicity (kg 1,4-DB eq) 4.62 10 4 1.01 10 4 1.26 10 3 1.26 10 3 × − × − × − × − Ecotoxicity of fresh water (kg q,4-DB eq) 1.25 10 5 2.73 10 6 3.40 10 5 3.40 10 5 × − × − × − × − Ecotoxicity of sea water (kg 1,4-DB eq) 1.14 10 5 2.48 10 6 3.40 10 5 3.08 10 5 × − × − × − × − Use of agricultural land (m2a) 4.99 10 5 1.09 10 5 1.35 10 4 1.35 10 4 × − × − × − × − Natural land use (m2a) 2.34 10 7 5.05 10 8 6.30 10 7 6.30 10 7 × − × − × − × − Depletion of fossil resources (kg oil eq) 4.15 10 4 9.01 10 5 1.12 10 3 1.12 10 3 × − × − × − × −

3.2. Integrated Value Stream Mapping with Life Cycle Analysis The VSM results of the current state production process are shown in Figure7. It was identiﬁed thatAppl. 5.58Sci. 2020 kg, CO10, x2 /FORkg wouldPEER REVIEW be emitted, similar to that reported in other countries (Table1). 9 of 14

Figure 7. Climate change emissions from the current egg production process. Figure 7. Climate change emissions from the current egg production process. The results of the VSM, considering equipment with greater energy efficiency in the production The results of the VSM, considering equipment with greater energy efficiency in the production stages, are presented in Figure8. It was identified that the farm has an energy demand of 14,646.3 stages, are presented in Figure 8. It was identified that the farm has an energy demand of 14,646.3 kWh in the production cycle, and that fluorescent bulbs for lighting are the equipment with the highest kWh in the production cycle, and that fluorescent bulbs for lighting are the equipment with the units, number of hours in function, and the highest energy consumption. The specific energy used in highest units, number of hours in function, and the highest energy consumption. The specific energy the production of 1 kg of eggs from the studied farm was 0.0081 kWh/kg, and the energy productivity used in the production of 1 kg of eggs from the studied farm was 0.0081 kWh/kg, and the energy was 122.6 kg/kWh. This value is higher than that found by [26], who reported specific energy of 0.004 productivity was 122.6 kg/kWh. This value is higher than that found by [26], who reported specific kWh/kg for eggs, due to energy consumption of 365,770 kWh/production cycle, and production of energy of 0.004 kWh/kg for eggs, due to energy consumption of 365,770 kWh/production cycle, and production of 65,084,680 kilograms of eggs. However, the differences are possibly explained by the differing degrees of each farm’s technification. One of the sources that does not provide added value to operations within the energy efficiency of a process is the overvaluation of consumption per power equipment. This is where adjustments are made for efficient operation, reducing consumption without compromising production. When looking for efficiency in lighting by replacing bulbs, it is advisable to look for the equivalent in lumen (lm) rather than watts, because lumen indicate the amount of light emitted rather than the energy consumed. When the motors are working at a high torque they slowly accelerate from low revolutions, thus maintaining better efficiency in transporting material. Figure 9 shows the VSM of the expected future state of the shelf egg production process. Subsequently, Table 7 shows the possible energy saving per operation. Appl. Sci. 2020, 10, 1352 10 of 14

65,084,680 kilograms of eggs. However, the differences are possibly explained by the differing degrees Appl.of each Sci. 2020 farm’s, 10, technification.x FOR PEER REVIEW 10 of 14

Figure 8. Consumption and cost of energy flows from unitary operations in egg production at Figure 8. Consumption and cost of energy flows from unitary operations in egg production at current current state. state. One of the sources that does not provide added value to operations within the energy efficiency Table 7. Comparison of the energy expenditure of the current state vs. the eco-efficient scenario for of a process is the overvaluation of consumption per power equipment. This is where adjustments the egg production process at Laguna Colorada farm. are made for efficient operation, reducing consumption without compromising production. When Current Scenario Expenditure Eco-Efficient Scenario Expenditure lookingUnit for Operation efficiency in lighting by replacing bulbs, it is advisable to look for the equivalentReduction in lumen(%) (lm) rather than watts, because lumen(kWh) indicate the amount of light(kWh)emitted rather than the energy Illumination 6298.1 2448.4 61.1 consumed.Water pump When the motors are working3867.7 at a high torque they slowly1933.6 accelerate from low revolutions,50.0 thus maintainingFood supply better efficiency1481.6 in transporting material. Figure987.09 shows the VSM of the33.4 expected futureExtraction state of the shelf egg production2961.4 process. Subsequently,1984.5 Table 7 shows the possible33.0 energy saving per operation.

Table 7. Comparison of the energy expenditure of the current state vs. the eco-eﬃcient scenario for the egg production process at Laguna Colorada farm.

Current Scenario Eco-Eﬃcient Scenario Unit Operation Reduction (%) Expenditure (kWh) Expenditure (kWh) Illumination 6298.1 2448.4 61.1 Water pump 3867.7 1933.6 50.0 Food supply 1481.6 987.0 33.4 Extraction 2961.4 1984.5 33.0 Appl. Sci. 2020, 10, 1352 11 of 14 Appl. Sci. 2020, 10, x FOR PEER REVIEW 11 of 14

Figure 9. Energy consumption and cost of the expected future scenario of energy flow from unit Figure 9. Energy consumption and cost of the expected future scenario of energy flow from unit operations in egg production at a future state. operations in egg production at a future state. With the eco-efficient scheme and the adjustment of the consumption/power ratio in the equipment, With the eco-efficient scheme and the adjustment of the consumption/power ratio in the it would be possible to obtain a 49.5% reduction in the farm’s total energy consumption without equipment, it would be possible to obtain a 49.5% reduction in the farm’s total energy consumption compromising the current production process. There would also be an average saving of 56.3% in without compromising the current production process. There would also be an average saving of environmental impacts for the electrical cost of egg production. A monetary saving of 686.3 USD (June 56.3% in environmental impacts for the electrical cost of egg production. A monetary saving of 686.3 2019) would be recorded for each production cycle. Illumination, which is the process with the highest USD (June 2019) would be recorded for each production cycle. Illumination, which is the process with energy demand, would have a 61.10% reduction with the substitution of LED spotlights. the highest energy demand, would have a 61.10% reduction with the substitution of LED spotlights. The difference in the reduction of these potentials (Table5) is known as an externality. These are The difference in the reduction of these potentials (Table 5) is known as an externality. These are activities that affect third parties without having the need to pay for them or to be compensated by activities that affect third parties without having the need to pay for them or to be compensated by the final client. There are methodologies for environmental economics that allow conversion of the the final client. There are methodologies for environmental economics that allow conversion of the internalization of such externalities. One is the cost-effectiveness analysis, which focuses on seeking an internalization of such externalities. One is the cost-effectiveness analysis, which focuses on seeking internal benefit in production, as well as a social benefit. Table8 shows the social benefit equivalent to an internal benefit in production, as well as a social benefit. Table 8 shows the social benefit equivalent various variables for each kilogram of CO2 (i.e., not emitted into the atmosphere). The integration of to various variables for each kilogram of CO2 (i.e., not emitted into the atmosphere). The integration this type of improvement is not limited to the type of process. It can be applied to be more productive of this type of improvement is not limited to the type of process. It can be applied to be more in industrial processes with less raw materials in mechanical, electrical, chemical, transportation productive in industrial processes with less raw materials in mechanical, electrical, chemical, equipment, food, textile, graphics arts, and stationery industries, among others. transportation equipment, food, textile, graphics arts, and stationery industries, among others.

Appl. Sci. 2020, 10, 1352 12 of 14

Table 8. Social beneﬁts obtained, comparing both scenarios of egg production in activities equivalent

to 1 kg CO2 eq [27,28].

Estimated Equivalence 1 kg Estimated Consumption Estimated Social Variable Consumption at CO /Variable at Eco-Eﬃcient Scenario Beneﬁt 2 Current Scenario Diesel (L) 2.34 21,649 9434 12,215 Gas LP (L) 1.49 13,813 6019 7794 Crude oil (L) 2.21 20,483 8926 11,557

4. Conclusions The findings in this study contribute to improving the sustainable performance of the poultry industry and reducing its environmental impact. Lean manufacturing techniques, such as VSM, can improve the process by identifying opportunities for eliminating waste. The application of LCA to a study allows knowledge of the quality of the manufacturing process concerning the environment when identifying environmental impacts. However, when both technics are integrated, a visualization of the process with an eco-efficient approach is provided. This integral framework (LCA and VSM) helps to facilitate sustainable productivity and provides scientific value, intending to ensure best practices. Additionally, this framework offers leveraged benefits that meet lean and environmental needs.

4.1. Limitations Section Comparisons of LCA are complicated, even when using the same methodology, as results can • differ with particular assumptions in each study. The results of an LCA study with national- or regional-level approaches may not be accurate • for local applications, or vice versa. This study has an important geographical limitation to consider. The studied farm is located in the main egg-producing zone in Mexico (Jalisco State), which has favourable weather conditions for this activity. Other important egg-producing farms in Mexico are located in hot-dry or hot-humid climates. To provide thermal comfort to laying hens, technified farms are likely to use different technologies than those reported here. Different, additional, newer, or more modern equipment would imply variations of energy consumption as well. Therefore, the results from this semi-technified farm may not be suitable for small farms that employ manual handling. The VSM results are also related to the limitations described for LCA. • 4.2. Future Research Plan The technification index for farms has not been reported in Mexico for the poultry sector. Therefore, the official reports of national greenhouse gases (GHG) for this sector do not consider differences among national shelf egg, hatching egg, or poultry production. For this reason, it is important to develop new research in this sector to recognize the real efficiency, impacts, and opportunities for energy management and limitation of environmental footprints.

Author Contributions: P.A.T.-G. and L.M.-B. conceived the idea; I.E.E.-G. conducted LCA and VSM analyses; I.E.E.-G. and H.G.-G.-R. conducted the environmental economy calculation; I.E.E.-G. and L.M.-B. wrote the paper; P.A.T.-G. and H.G.-G.-R. proofread the manuscript. All authors have read and agreed to the published version of the manuscript. Funding: Authors gratefully acknowledge the generous funding of CONACyT (México) through scholarship grant no. 475832. Also, the contribution of the UMSNH-CIC project is recognized. Conﬂicts of Interest: The authors declare no conﬂict of interest. Appl. Sci. 2020, 10, 1352 13 of 14

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