Assessment of Passive Retrofitting Strategies to Improve the Thermal

sustainability

Article Assessment of Passive Retroﬁtting Strategies to Improve the Thermal Performance of Extra-Virgin Olive Oil Storage Area in Traditional Rural Olive Mills

Francesco Barreca * and Pasquale Praticò Department of Agraria, Università degli Studi Mediterranea di Reggio Calabria, 89122 Reggio Calabria RC, Italy; [email protected] * Correspondence: [email protected]

Received: 30 November 2019; Accepted: 23 December 2019; Published: 25 December 2019

Abstract: The quality of extra-virgin olive oil (EVOO) is strongly correlated to the fatty acid alkyl esters (FAEE) content. High storage temperature leads to degradation of positive oil attributes in the long term, while low temperature develops rancidity quickly, thus reducing the consumer’s acceptance and, therefore, the shelf life of EVOO. In Calabria, there are many traditional olive mills, yet only few are utilized nowadays. This is mainly due to the low building performance—in particular to the temperature control inside the oil storage area. This paper illustrates the thermal analysis carried out on a famous historical olive mill located in Lamezia Terme, the best agricultural land in Calabria. A thermal retroﬁtting assessment was conducted, and eight diﬀerent passive strategies were evaluated to improve the sustainability of the buildings.

Keywords: olive oil mills; thermal analysis; traditional rural buildings; phase change materials

1. Introduction In the last 50 years, the crisis of industrial development has led researchers and government associations to become more interested in the traditional rural heritage [1]. Various European and national programmes and financial projects have dealt with the reuse and the valorisation of traditional rural buildings [2]. Their value is considered a social plus-value, because they are strongly linked to the local history, community and landscape of a territory. Unfortunately, owing to the great number of traditional rural buildings, many of which being abandoned or destroyed and to the limited public financial resources available, in Italy, the conservation of this important traditional heritage has become extremely difficult. Thanks to their potential uses, traditional rural buildings have attracted private entrepreneurs [3], who have demonstrated their capacity of reusing traditional rural buildings in different fields and activities: as tourist facilities, meeting places, conference halls, restaurants, hotels, museums, residential centres, recording studios and much more. To keep the original use of traditional rural buildings is often extremely difficult because of the increasing speed of technological innovation in agriculture and in food processing. In particular, modern food processing buildings require a greater number of performances than in the past. They need more flexibility in order to meet the consumer’s demand [4]. They have to be equipped with modern processing machines, to respect new food hygiene rules and to guarantee workers’ safety [5]. For all the above reasons, it is very important to define specific criteria to consider the rehabilitation of traditional rural buildings, since, in general, rehabilitating them costs much more than building modern ones. [6] Nowadays, one of the main operational difficulties in the rehabilitation of traditional buildings is the availability of craftsmen capable of working the local materials with traditional techniques. Nevertheless, reusing

Sustainability 2020, 12, 194; doi:10.3390/su12010194 www.mdpi.com/journal/sustainability Sustainability 2020, 12, 194 2 of 11 Sustainability 2019, 11, x FOR PEER REVIEW 2 of 11 anrural old land building can be on advantageous rural land can for be advantageousthe local community for the since local communityit can help protect since it the can architectural help protect theheritage architectural and conserve heritage the and regional conserve landscape the regional character landscape as long character as the new as long functions as the introduced new functions are introducedcompatible arewith compatible the original with characteristics the original characteristicsof the buildings. of In the fact, buildings. reuse is Inpossible fact, reuse if it isimplies possible little if itintervention implies little on intervention the original on building the original structure building [7]. However, structure [it7]. is However, necessary it to is remark necessary that to modern remark thatrural modern buildings rural and buildings food processing and food buildings processing are re buildingsquired to are have required particular to have indoor particular environmental indoor environmentalcharacteristics characteristicsbecause the indoor because microclimate the indoor microclimateinfluences the inﬂuences chemical, the physical chemical, and physical biological and biologicalchanges taking changes place taking during place the during production the production process [8,9]. process [8,9].

2.2. Traditional OilOil MillsMills inin CalabriaCalabria 3 3 SpainSpain (1271(1271 × 103 t)t) and and Italy (429 × 10103 t)t) are are the the main main producers producers of of olive olive oil oil in Europe and Italy × × 3 is the major consumer of olive oil (560 103 t) [10]. is the major consumer of olive oil (560 ×× 10 t) [10]. Apulia,Apulia, inin Italy, isis thethe ﬁrstfirst productionproduction region,region, withwith 33%33% ofof oliveolive grovegrove surfacesurface area,area, followedfollowed by Calabria,Calabria, with 17% (184,000 ha), of whichwhich about 1550 ha are tabletable oliveolive grovesgroves andand aboutabout 183 haha areare oiloil oliveolive groves,groves, producingproducing 140,000140,000 tonstons ofof oliveolive oiloil annuallyannually [[11].11]. Olive trees areare thethe mostmost cultivatedcultivated plantsplants andand thethe mostmost importantimportant supplysupply chainchain inin Calabria,Calabria, thusthus considerablyconsiderably contributingcontributing toto thethe locallocal ruralrural economyeconomy [ 12[12].]. The The largest largest surface surface areas areas are are in thein the provinces provinces of Cosenzaof Cosenza and and Reggio Reggio Calabria Calabria [13]. In[13]. particular, In particular, the province the province of Reggio of Reggio Calabria Calabria boasts boasts the highest the highest number number of olive of olive mills mills (304) (304) and and the highestthe highest quantity quantity of olive of olive oil production oil production (26,555 (26,555 t) [14 t)]. [14]. InIn thethe mid-eighteenthmid-eighteenth century,century, followingfollowing thethe technologicaltechnological improvementimprovement inin agricultureagriculture andand thethe innovationinnovation ofof thethe oliveolive oiloil extractionextraction machinemachine (Grimaldi’s(Grimaldi’s method),method), oliveolive oiloil millsmills spreadspread inin thethe southsouth ofof thethe regionregion CalabriaCalabria (Italy). (Italy). There There were were two two main main production production areas areas in in Calabria Calabria in in that that period: period: one one in thein the Gioia Gioia Tauro Tauro plain, plain, in thein the province province of Reggio of Reggio Calabria, Calabria, and and the the other other near near Lamezia Lamezia Terme, Terme, in the in provincethe province of Catanzaro of Catanzaro (Figure (Figure1). 1).

Figure 1.1. Main olive oil production areas inin thethe mid-eighteenthmid-eighteenth centurycentury inin Calabria.Calabria.

In the Gioia Tauro Plain, production focused on husk oil, which was mainly used in the soap In the Gioia Tauro Plain, production focused on husk oil, which was mainly used in the soap industry; while, in Lamezia Terme, production was oriented to high quality olive oil to use in food [15]. industry; while, in Lamezia Terme, production was oriented to high quality olive oil to use in food The architectural styles of the olive mills in these areas were also diﬀerent: in the Gioia Tauro Plain, [15]. The architectural styles of the olive mills in these areas were also different: in the Gioia Tauro olive mills (type A) were characterized by a very simple architecture with a large plan equipped for Plain, olive mills (type A) were characterized by a very simple architecture with a large plan equipped getting the most out of the olive paste using washing techniques (Figure2). for getting the most out of the olive paste using washing techniques (Figure 2).

(a) (b)

Figure 2. Typical olive oiloil millmill inin GioiaGioia TauroTauro (type(type A).A). ((aa)) FacadeFacade ((bb)) Layout.Layout (a) (b)

Figure 2. Typical olive oil mill in Gioia Tauro (type A). (a) Facade (b) Layout.

(a) (b)

Figure 3. Typical olive oil mill in Lamezia Terme (type B). (a) Facade (b) Layout

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In the area of Lamezia Terme, olive mills (type B) were smaller and higher than in the Gioia

SustainabilityTauro Plain, 2019 with, 11, twox FOR floors PEER toREVIEW better store the olives on the first floor and to easily move them to3 of the 11 (a) (b) processing area on the ground floor without squeezing the olive fruits (Figure3). The buildings were erectedIn the near area streams Figureof Lamezia so 2. that,Typical Terme, by olive means oliveoil mill of mills a in water Gioia (type wheel,Tauro B) were(type they A).smaller could (a) Facade useand water higher(b) Layout energy than in to movethe Gioia the Taurostone wheelsPlain, with that two pressed floors the to olives better to store obtain the the olives oil. on the first floor and to easily move them to the processing area on the ground floor without squeezing the olive fruits (Figure 3). The buildings were erected near streams so that, by means of a water wheel, they could use water energy to move the stone wheels that pressed the olives to obtain the oil.

(a) (b) (a) (b) FigureFigure 3.3. TypicalTypical oliveolive oiloil millmill inin LameziaLamezia TermeTerme (type (type B). B). ( a(a)) Facade Facade ( b(b)) Layout. Layout Figure 3. Typical olive oil mill in Lamezia Terme (type B). (a) Facade (b) Layout. The processing area was aired and lit by large windows with insect screens. The surface of the floorThe was processing in ceramic area tiles was or woodaired and with lit a by slight large slope windows to let thewith cleaning insect screens. water andThe thesurface oil spilled of the floorout during was inthe ceramic process tiles drain or wood away. with In thesea slight buildings, slope to thelet the olive cleaning processing water area and was the oil often spilled divided out duringinto diff theerent process levels: drain the millaway. and In thethese presses buildings, were the located olive inprocessing the upper area area, was while often the divided containers into withdifferent the levels: just-pressed the mill must and/oil the were presses in thewere lower locat area.ed in the In thisupper area, area, the while oil was the separatedcontainers fromwith the waterjust-pressed and transferred must/oil were into ain special the lower room area. next In to this the area, mill, the called oil waschiaritoio separated. In this from room, the thewater oil wasand transferredclarified by into means a special of decanting room next cycles to the using mill, terracotta called chiaritoio churns.. In The this olive room, oil the was oil stored was clarified in big clay by meanspots that of weredecanting placed cycles underground using terracotta to protect churns. them The from olive high oil summer was stored temperatures in big clay and pots by that recurrent were placedearthquakes underground [16] (Figure to protect4). them from high summer temperatures and by recurrent earthquakes [16] (Figure 4).

Figure 4. ChiaritoioChiaritoio withwith clay clay pot pot placed placed underground to store olive oil.

The indoor indoor environment environment of of the the storage storage room room infl influencesuences the the product product quality. quality. In particular, In particular, the temperaturethe temperature andand the thelight light of ofthe the storage storage environmen environmentt could could deteriorate deteriorate the the quality quality of of extra-virgin olive oil (EVOO), which is strongly correlated to the fatty acidacid alkylalkyl esterester (FAEE)(FAEE) content.content. FAEE determines the organoleptic profile profile of an EVOO, which plays a relevant role in olive oil classification classification due to to the the fact fact that that it itis isincluded included in inthe the quality quality parameters parameters [17]. [17 It]. has It been has been demonstrated demonstrated that a that high a FAAEhigh FAAE concentration concentration is the is theresult result of the of theuse use of ofolive olive fruits fruits with with fermentative fermentative alterations alterations and and high maturity index for oil extraction. A few studies have highlighted the relationship between FAEE in olive oil and the defects due to olive fermentation which affect its sensory classification. That is the reason why, in 2016, the European Commission Regulation defined the value of legal limit for the EVOO to 30 mg/kg. An incorrect storage temperature interval alters not only the FAEE of the olive oil but also other quality parameters, such as peroxide. In fact, high storage temperature, i.e., over 24

Sustainability 2020, 12, 194 4 of 11 maturity index for oil extraction. A few studies have highlighted the relationship between FAEE in olive oil and the defects due to olive fermentation which affect its sensory classification. That is the reason why, in 2016, the European Commission Regulation defined the value of legal limit for the EVOO to 30 mg/kg. An incorrect storage temperature interval alters not only the FAEE of the olive oil but also other quality parameters, such as peroxide. In fact, high storage temperature, i.e., over 24 ◦C, leads to degradation of positive oil attributes in the long term, while low temperature develops rancidity quickly, thus reducing the consumer’s acceptance and, therefore, the shelf life of EVOO [18]. During the storage phase of EVOO, polyphenols tend to decrease and compromise its dietetic and nutritional qualities and taste as well as to produce harmful substances for human health [19]. Low storage temperature also affects the EVOO quality, though less than high storage temperature. Researchers noticed that, over a period of 15 days, storage temperature below 4 ◦C caused a decrease of about 50% of the total polyphenols compared to freshly made EVOO [20]. A typical Calabrian EVOO is produced with Carolea monovarietal olives, stored in stainless steel tanks placed in a dark environment for an average storage time of 12 months. The best range of temperature is from 8 to 22 ◦C[20]. Usually, the conservation stage is the major energy consumer in food processing, because the energy spent for product units is related to the time of conservation, which often exceeds one year. For these reasons, the thermal control of the EVOO storage environment is very important and the use of passive solutions could improve the energy savings of the production. Reggio Calabria has a typical Mediterranean climate, with a mild temperature in winter (T > 0 ◦C) and warm summers (Tmax > 30 ◦C), with a strong day time and night time change of temperature. In the summer, the environmental indoor temperature of the EVOO mill storage area is often higher than 35 ◦C[8]. For this reason, it is very important to control the temperature of the storage environment in the EVOO mills in Calabria. The present study proposes the use of a passive retrofitting solution system on the building envelope.

3. Materials and Methods The case study analysed is an olive mill which is part of a larger historic rural building complex located in Lamezia Terme, a town in the province of Catanzaro (38◦55020.593” N 16◦19027.082” E). This complex dates back to 1750 and it is one of the best preserved rural complexes in Calabria. The olive oil mill has a modern continuous milling system. The extra-virgin olive oil it produces is extracted from Carolea cultivar olives, exclusively grown in the company’s olive groves, which have an annual yield of about 50,000 L. These olive groves have been on this farm for over 300 years and many of the olive trees are hundreds of years old. The olive oil farm covers an area of 300 hectares including a hillside where there are some olive trees on the southern side of the hill. The Carolea olive tree is characterized by small, straight, narrow leaves and produces medium-sized olives which ripen around the middle of October. A high quality extra-virgin olive oil with an excellent organoleptic result is obtained from immediate milling after harvest. Milling starts in the early weeks of October and continues until March. The produced extra-virgin olive oil is kept in stainless steel tanks for a few months and then bottled during the year, according to the market demand.

The Olive Oil Mill Building The olive oil mill is an ancient brick masonry building with a pitched roof in wood. The layout is very simple; the main processing area is a 50 8 m rectangle with a max 6 m height at the roof ridge. × In the main area, there is the olive storage area, the pre-processing area with the machine for fruit handling and receival and the machine for removing leaves and washing the drupes. Next to this area, there is the processing area with the crushing and malaxing machines and the oil separation machine (Figure5). Adjacent to the processing area, there is the service area with a little laboratory for the olive Sustainability 2019, 11, x FOR PEER REVIEW 5 of 11 Sustainability 2020, 12, 194 5 of 11 Sustainability 2019, 11, x FOR PEER REVIEW 5 of 11

oil analysis, the workers’ restroom and the olive oil storage area. The olive oil storage area is a 7 4 m × room with an external window without any separation from the main processing area.

Figure 5. Layout of the olive oil mill. Figure 5. Layout of the olive oil mill. Figure 5. Layout of the olive oil mill. The external wall and the window of the storage area are oriented to the south–west. Since this The external wall and the window of the storage area are oriented to the south–west. Since this is is the part of the building most exposed to sun radiation, in the summer, its indoor temperature is the partThe of external the building wall most and the exposed window to sun of radiation,the storage in area the summer, are oriented its indoor to the temperature south–west. is Since very hot.this very hot. Specific thermal surveys were carried out [21] to evaluate the thermal indoor condition. In Specificis the part thermal of the surveys building were most carried exposed out [to21 ]sun to evaluateradiation, the in thermal the summer, indoor its condition. indoor temperature In particular, is particular, an instrumental analysis was carried out from 19 July to 29 September 2016 to intercept anvery instrumental hot. Specific analysis thermal was surveys carried were out carried from 19 out July [21] to to 29 evaluate September the 2016thermal to intercept indoor condition. the hottest In the hottest summer season period. Two surface temperature sensors and two heat flow sensors were summerparticular, season an instrumental period. Two analys surfaceis was temperature carried out sensors from and19 July two to heat 29 flowSeptember sensors 2016 were to installedintercept installed on the surface of internal walls (T5–F2), while two other pairs of heat flow meters and surface onthe the hottest surface summer of internal season walls period. (T5 –FTwo2), whilesurface two temperature other pairs sensors of heat and flow two meters heat flow and surfacesensors heatwere heat sensors were installed on the ceiling and on the roof indoor surface (Tf–Ff; Tr–Fr). Two sensorsinstalled were on the installed surface on of theinternal ceiling walls and (T on5–F the2), while roof indoor two other surface pairs (T off–F hef;Tat rflow–Fr). meters Two temperature and surface temperature sensors (T1–T2) were mounted on the surface of external walls and a first class sensorsheat sensors (T –T )were were installed mounted on thethe surfaceceiling ofand external on the walls roof and indoor a first classsurface pyranometer (Tf–Ff; Tr–F forr). solarTwo pyranometer1 for2 solar irradiance measurement, according to ISO 9060 (Figure 6a) (P), was mounted irradiancetemperature measurement, sensors (T1 according–T2) were to mounted ISO 9060 (Figureon the6 a)surface (P), was of mountedexternal onwalls the externaland a first window. class on the external window. The indoor air temperature was surveyed by means of two specific sensors Thepyranometer indoor air for temperature solar irradiance was surveyed measurement, by means according of two specificto ISO 9060 sensors (Figur mountede 6a) (P), on was two mounted tripods, mounted on two tripods, one located in the centre of the room (Ta) and the other in the attic (Tar). oneon the located external in the window. centre of The the indoor room (T aira) temperature and the other was in the surveyed attic (T arby). means Another of surfacetwo specific temperature sensors Another surface temperature sensor was installed on the olive oil stainless steel tank (T3). A weather sensormounted was on installed two tripods, on the one olive located oil stainless in the steel centre tank of (T the). Aroom weather (Ta) and station the wasother placed in the close attic to (T thear). station was placed close to the building to survey the meteorological3 data (Figure 6b). All the data buildingAnother tosurface survey temperature the meteorological sensor was data instal (Figureled 6onb). the All olive the data oil stainless surveyed steel by thetank sensor (T3). A network weather surveyed by the sensor network were recorded at a time interval of 15 min by a data logger [22]. The werestation recorded was placed at a time close interval to the of building 15 min by to asurvey data logger the meteorological [22]. The surveyed data data(Figure showed 6b). that,All the during data surveyed data showed that, during the monitoring period, the temperature in the oil storage area thesurveyed monitoring by the period, sensor the network temperature were recorded in the oil at storage a time area interval was sometimesof 15 min by above a data 30 loggerC, a value[22]. The far was sometimes above 30 °C, a value far higher than the maximum correct temperature for◦ the proper highersurveyed than data the maximumshowed that, correct during temperature the monitoring for the period, proper storagethe temperature of extra-virgin in the olive oil storage oil. area storage of extra-virgin olive oil. was sometimes above 30 °C, a value far higher than the maximum correct temperature for the proper storage of extra-virgin olive oil.

(a) (b)

FigureFigure 6. 6. (a()a )Installed Installed instrumental instrumental(a) network; network; (b (b) )outdoor outdoor weather( weatherb) station. station.

Figure 6. (a) Installed instrumental network; (b) outdoor weather station.

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4. Results Results The measured thermal values showed that, du duringring the monitoring period, the indoor air temperature in the oil storage area sometimes reached and exceeded 30 °C and that the building temperature in the oil storage area sometimes reached and exceeded 30 ◦C and that the building oﬀered offeredinadequate inadequate protection protection from high from summer high summer temperatures temperatures (Figure7 (Figure). 7).

Figure 7. Outdoor and indoor measured air temperature. Figure 7. Outdoor and indoor measured air temperature. It was necessary to design and verify specific retrofitting solutions to improve the thermal performanceIt was necessary of the building. to design and verify specific retrofitting solutions to improve the thermal performanceThe thermal of the analysis building. of the case-study building was carried out by means of DesignBuilder, a buildingThe thermalenergy analysis simulation of the software case-study based building on a dynamic was carried thermal out simulationby means of method DesignBuilder, (DTS) [23 a]. buildingDTS is a methodenergy simulation used to predict software the way based a buildingon a dynamic responds thermal when simulation subject to method external (DTS) environmental [23]. DTS isfactors. a method To achieveused to this,predict all necessarythe way a parametersbuilding responds of design when are takensubject into to external consideration, environmental such as: factors.occupancy To patterns,achieve internalthis, all heatnece gainsssary andparameters building fabricof design characteristics are taken thatinto could consideration, affect the result such [ 24as:]. occupancyIt is very important patterns, to internal consider heat the gains influence and ofbuilding environmental fabric characteristics factors affecting that the could indoor affect environment, the result which[24]. It dependis very onimportant weather conditionsto consider that the areinfluence variable of during environmental the day and factors during affecting the yearly the seasons.indoor environment,The heat flow which through depend walls on is determinedweather conditions not just th byat theare areavariable and during the temperatures, the day and butduring also the by yearlythe mass seasons. characteristics The heat flow of the through walls, whichwalls is may determined result in not heat just flowing by the outarea of and a wall the temperatures, several hours butlater also [25 by,26 the]. Solar mass energycharacteristics is absorbed of the by walls, the which exterior may walls result and in roofheat surfacesflowing out as wellof a wall as through several windows.hours later The [25,26]. intensity Solar ofenergy solar energyis absorbed varies by according the exterior to thewalls position and roof of thesurfaces sun during as well the as through day and windows.over the year. The Inintensity addition, of thesolar ground energy and varies the accord grounding floor to the are position an infinite of thermalthe sun during source the which day has and a overconstant the year. temperature In addition, and exchangesthe ground heat and with the ground the indoor floor environment are an infinite [27 thermal]. Heat sources source withinwhich has the abuilding, constant including temperature people, and oexchangesffice and other heat equipment,with the indoor have environment an immediate [27]. impact Heat on sources the indoor within air the(convective building, heat) including and the people, heat thatoffice is and absorbed other equi by thepment, surfaces have is an released immediate slowly impact over on time the (radiant indoor airheat) (convective [28]. Air conditioningheat) and the and heat heating that is absorbed systems can by the also surfaces be used is with released many slowly different over control time (radiant systems heat)based [28]. on theAir temperatureconditioning or and other heating conditions systems within can also each be spaceused with of the many building different and control their operation systems basedaccounts on forthe atemperature large portion or of other the energy conditions consumed within in each a building. space of By the means building of Energy and their+, the operation dynamic accountssimulation for engine a large ofportion DesignBuilder, of the energy it was consum possibleed in to a building. consider allBy means these parameters of Energy+, andthe dynamic estimate simulationthe indoor engine temperature of DesignBuilder, and the energy it was spent possible by an to HAVC consider system all these to maintain parameters the optimaland estimate olive the oil indoor temperature and the energy spent by an HAVC system to maintain the optimal olive oil storage temperature in the range (8–21 ◦C) suitable to guarantee the quality of the EVOO produced storage(Figure8 temperature)[29]. in the range (8–21 °C) suitable to guarantee the quality of the EVOO produced (Figure 8) [29].

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35 Sustainability302020, 12, 194 Air temperature 7 of 11 max limit Sustainability 2019, 11, x FOR PEER REVIEW 7 of 11 25 min limit 20 3515 Temp [°C] Temp 3010 Air temperature max limit 255 min limit 200 15 Temp [°C] Temp 10 Time 5 0 Figure 8. Temperature inside the olive oil storage room (model A).

The results of the building analysis (model A) highlighted that the indoor temperature was never below 8 °C, but, during the summer, it was oftenTime over 21 °C. For this reason, the energy spent was only to cool the indoor environment of the olive oil storage room. Seven different building retrofitting solutions were analysedFigureFigure to 8. assess Temperature 8. Temperature the best inside energy inside the the savingolive olive oil solution. oilstorage storage room room (model (model A). A). Solution 1: the oil storage area was separated from the processing area by means of a 6 cm thick polyurethaneTheThe results results wall of ofthesandwich the building building panel. analysis analysis (model (model A) A)highlighted highlighted that that the the indoor indoor temperature temperature was was never never belowbelowSolution 8 °C, 8 ◦ C,but, 2: but, the during duringexternal the the wallsummer, summer, was shadedit was it was often by often outdoor over over 21 shading 21°C.◦ C.For For elements. this this reason, reason, the the energy energy spent spent was was onlyonly toSolution tocool cool the 3: the indoorthe indoor walls environmentenvironment and the roof of ofthe of the olivethe olive olive oil oilstorage oil storage storage room. room. room Seven Seven were different di ﬀinsulatederent building building by retrofitting6 cm retroﬁtting thick solutionspolyurethanesolutions were were panels analysed analysed (Figure to toassess 9) assess and the the best external best energy energy window saving saving solution.was solution. eliminated. SolutionSolution 1:4: the 1:a spacethe oil oilstorage ventilation storage area area waswas was madeseparated separated on the from fromroof the and the processing processingnatural ventilation area area byby means meanswas ofactivated ofa 6 a cm 6 cm thickfrom thick polyurethane20:00polyurethane to 08:00. wall wall sandwich sandwich panel. panel. SolutionSolution 2:5: the 2:a Canadianthe external external wellwall wall waswas was installedshaded shaded by toby outdoorventilate outdoor shading indoors shading elements. from elements. 20:00 to 08:00. SolutionSolution 6:3: an 3:the internalthe walls walls and fan and wasthe the roof installed roof of ofthe to the oliveforce olive oilventilation oilstorage storage roomfrom room 20:00were were toinsulated 08:00. insulated by by6 cm 6 cm thick thick polyurethanepolyurethaneSolution 7:panels the panels walls (Figure (Figure and 9) 9the and) and roof the the ofexternal external the olive window window oil storage was was eliminated. were eliminated. insulated by means of an 18 °C phaseSolution changeSolution 4: material a 4: spacea space layer.ventilation ventilation was was made made on onthe the roof roof and and natural natural ventilation ventilation was was activated activated from from 20:0020:00The to to08:00. energy 08:00. analysis was carried out considering building models with different combinations of solutions.SolutionSolution In5: particular,a 5: Canadiana Canadian mode well well lwas Awas was installed installedthe real to building toventilate ventilate without indoors indoors any from from retrofitting 20:00 20:00 to to08:00. intervention; 08:00. model I wasSolution theSolution model 6: an 6: with aninternal internal the external fan fan was was wallinstalled installed shaded to toforce by force means ventilation ventilation of outdoor from from 20:00shading 20:00 to to08:00. elements 08:00. and the wall and roofSolutionSolution insulated 7: 7:thethe bywalls means walls and and of the a the 18roof °C roof ofphase ofthe the olivechange olive oil material oil storage storage layer;were were insulatedthe insulated other modelsby by means means analysed of ofan an 18 were 18°C◦ C phasethephase different change change combinations material material layer. layer. of the solutions mentioned above (Table 1). The energy analysis was carried out considering building models with different combinations of solutions. In particular, model A was the real6 building60 without any retrofitting intervention; model I was the model with the external wall shaded by means of outdoor shading elements and the wall and roof insulated by means of a 18 °C phase change material layer; the other models analysed were the different combinations of the solutions mentioned above (Table 1).

6 60

AB FigureFigure 9. Solution 9. Solution 3: the 3:stone the wall stone of the wall olive of oil the stor oliveage area oil storageinsulated area by 6 insulated cm thick polyurethane by 6 cm thick panels.polyurethane panels.

The energy analysis was carried out considering building models with diﬀerent combinations of

solutions. In particular, model A was the real building without any retroﬁtting intervention; model I AB was the model with the external wall shaded by means of outdoor shading elements and the wall and Figure 9. Solution 3: the stone wall of the olive oil storage area insulated by 6 cm thick polyurethane roof insulated by means of a 18 ◦C phase change material layer; the other models analysed were the diﬀpanels.erent combinations of the solutions mentioned above (Table1).

Sustainability 2020, 12, 194 8 of 11 SustainabilitySustainabilitySustainabilitySustainabilitySustainability 2019 2019 2019 20192019,, , 11 11, ,,,11 , 11x 11xx ,FOR FOR ,FOR,x xx FOR FORFOR PEER PEERPEER PEER PEERPEER REVIEW REVIEWREVIEW REVIEW REVIEWREVIEW 88 of of888 of11 of11of 11 1111

Table 1. Models analysed obtained from the diﬀerent combinations of the proposed solutions. SustainabilityTableTableTableTableTable 2019 1.1. ,1. Models 1.Models1.11 Models Models,Models x FOR analysedanalysed PEERanalysed analysedanalysed REVIEW obtainedobtained obtained obtainedobtained fromfrom from fromfrom thethe the thethe differentdifferent different differentdifferent combinationscombinationscombinations combinations combinationscombinations ofofof of thetheoftheof the thethe proposedproposedproposed proposed proposedproposed solutions.solutions.solutions. solutions. solutions.solutions. 8 of 11 Original SOL 1 SOL 2 SOL 3 SOL 4 SOL 5 SOL 6 SOL 7 Table Original Original Original1. Original Original OriginalModels analysed SOL SOL SOL SOL SOL SOL 111 obtained 1 11 SOL SOL SOL SOL SOL SOL from 222 2 22 the SOL SOL SOL different SOL SOL SOL 333 3 33 SOL SOLcombinations SOL SOL SOL SOL 444 4 44 SOL SOL SOL of SOL SOL SOL the 555 5proposed 55 SOL SOL SOL SOL SOL SOL solutions. 666 6 66 SOL SOL SOL SOL SOL SOL 777 7 77

MODELMODELMODELMODELMODEL Original SOL 1 SOL 2 SOL 3 SOL 4 SOL 5 SOL 6 SOL 7

MODELAA A AA XX X XX AX BB BBB XX X XX BXA X CC C CC XX X XX XX X XX CXXB X DD D DD XX X XX XX X XX XX X XX C X X DXXXEE EEE XX X XX XX X XX XX X XX XX X XX D X X X FEXXXXF FFF X X X X X XX X XX XX X XX XX X XX XX X XX E X X X X GGFXXXXX G GG X X X X X XX X XX XX X XX XX X XX XX X XX XX X XX F X X X X X HH H HH X X X X X XX X XX XX X XX XX X XX XX X XX XX X XX XX X XX GXXXXXXG X X X X X X II III XX X XX XX X XX XX X XX HXXXXXXXH X X X X X X X TheTheIXXXTheTheIThe dynamicdynamic dynamicdynamicdynamic thermal thermal thermalthermalthermal analysisanalysis X analysisanalysisanalysis waswas waswaswas X carriedcarried carriedcarriedcarried outout outout out consideringconsidering consideringconsideringconsidering thethe thethethe closestclosest closestclosest closest WorldWorld WorldWorldWorld MeteorologicalMeteorological MeteorologicalMeteorologicalMeteorologicalX OrganizationOrganizationOrganizationOrganizationOrganization (WMO)(WMO) (WMO) (WMO)(WMO) weatherweather weather weatherweather locatedlocated located locatedlocated aboutabout about aboutabout 3535 35 35 km35km km kmkm westwest west westwest fromfrom from fromfrom thethe the thethe casecase case casecase studystudy study studystudy (38°12(38°12 (38°12 (38°12(38°12′′′ N,N,N,′ ′′N, N, N, 15°3315°3315°33 15°33 15°3315°33′′′ E).E).E).′ ′′E). E). E). TheTheThe The TheThe The dynamic thermal analysis was carried out considering the closest World Meteorological weatherweatherweatherweatherweather filefile file filefile isis is partispartis part partpart ofof of oftheofthe the thethe ItalianItalian Italian ItalianItalian ClimateClimate Climate ClimateClimate DataData Data DataData SetSet Set SetSet elaboratedelaborated elaborated elaboratedelaborated byby by byby GianniGianni Gianni GianniGianni dede de dede GiorgioGiorgio Giorgio GiorgioGiorgio withwith with withwith yearlyyearly yearly yearlyyearly datadata data datadata OrganizationThe dynamic (WMO) thermal weather analysis located was about carried 35 km out west considering from the case the study closest (38°12 World′ N, Meteorological 15°33′ E). The fromfromfromfromfromfrom 195119511951 1951 19511951 untiluntiluntil until untiluntil 1970.1970.1970. 1970. 1970.1970. weatherOrganization file is (WMO)part of the weather Italian located Climate about Data 35Set km elaborated west from by theGianni case de study Giorgio (38◦ with120 N, yearly 15◦33 data0 E). ForForForForFor eacheach eacheacheach buildingbuilding buildingbuildingbuilding energyenergy energyenergyenergy model,model, model,model,model, aa aspecificaspecifica specificspecificspecific energyenergy energyenergyenergy simulationsimulation simulationsimulationsimulation waswas waswaswas carriedcarried carriedcarriedcarried outout outoutout toto to totoassessassess assessassessassess thethe thethethe fromThe weather 1951 until ﬁle 1970. is part of the Italian Climate Data Set elaborated by Gianni de Giorgio with yearly energyenergyenergyenergyenergy spentspent spent spentspent byby by byby anan an an an electricelectric electric electricelectric HAVCHAVC HAVC HAVCHAVC toto to obtaintotoobtain obtain obtainobtain thethe the thethe meme me memeananan anan environmentalenvironmental environmental environmentalenvironmental temperaturetemperature temperature temperaturetemperature ofof of of21of21 21 21 °C21°C °C °C°C insideinside inside insideinside thethe the thethe dataFor from each 1951 building until 1970. energy model, a specific energy simulation was carried out to assess the oliveoliveoliveoliveolive oiloil oil oil oil storagestorage storage storagestorage room.room. room. room.room. energyFor spent each by building an electric energy HAVC model, to obtain a speciﬁc theenergy mean environmental simulation was temperature carried out to of assess 21 °C theinside energy the TheTheTheTheThe resultsresults results resultsresults ofof of oftheofthe the thethe dailydaily daily dailydaily thermalthermal thermal thermalthermal simulationsimulation simulation simulationsimulation areare are areare shownshown shown shownshown inin in inFigureinFigure Figure FigureFigure 10,10, 10, 10,10, whilewhile while whilewhile thethe the thethe energyenergy energy energyenergy spentspent spent spentspent forfor for forfor olivespent oil by storage an electric room. HAVC to obtain the mean environmental temperature of 21 ◦C inside the olive oil eacheacheacheacheach modelmodel model modelmodel isis isshown isshownis shown shownshown inin in inFigureinFigure Figure FigureFigure 11.11. 11. 11.11. storageThe room. results of the daily thermal simulation are shown in Figure 10, while the energy spent for each Themodel results is shown of the in daily Figure thermal 11. simulation are shown in Figure 10, while the energy spent for each model65 is6565 shown6565 in Figure 11. AA AAA BB BBB CC CCC DDDDD EE EEE FF FFF GGGGG HHHHH III III 6060606060 5555655555 55 A B C D E F G H I 505060505050 454555454545 404050404040 353545353535 303040303030 [kWh] [kWh] [kWh] [kWh] [kWh] [kWh] [kWh] [kWh] 252535252525 30

[kWh] 2020202020 151525151515 101020101010 5155 555 0100 000 5 0

FigureFigureFigureFigureFigureFigure 10.10. 10. 10.10. 10. DailyDailyDailyDaily DailyDailyDaily energyenergy energy energyenergyenergy spentspentspent spentspentspent by bybyby byHAVC by byHAVCHAVCHAVC HAVCHAVCHAVC to toto coolto to tocoolcooltocool the coolcoolcool thethethe olive thethe the ololol ive oilive oliveololiveive storageive oiloiloil oil oil oilstoragestoragestorage storage storagestorage room roomroomroom for roomroomroom di ﬀforforforerent forfor for differentdifferentdifferent differentdifferent buildingdifferent buildingbuildingbuilding buildingmodels.buildingbuilding modelsmodelsmodelsmodelsmodels...... Figure 10. Daily energy spent by HAVC to cool the olive oil storage room for different building models.

SustainabilitySustainability 20192020, ,1112, ,x 194 FOR PEER REVIEW 99 of of 11 11

5000 4161.84 4000 2770.82 3000 2267.43 2205.94

kWh 2000

1000 579.43 614.21 488.48 316.56 465.84 0 ABCDEFGH I

Figure 11. Yearly energy spent by HAVC to cool the olive oil storage room by diﬀerent building models. Figure 11. Yearly energy spent by HAVC to cool the olive oil storage room by different building 5. Discussionmodels.

The energy spent to maintain the temperature below 21 ◦C inside the original olive oil storage 5.room Discussion by means of a HAVC system was about 4161 KW/year (model A), while for the other models, whichThe adopted energy thespent passive to maintain retrofitting, the temperature it was lower. below The 21 analysis °C inside highlighted the original a great olive di oilfference storage in roomthe results by means between of a HAVC the models system considered. was about In 4161 solution KW/year 3, it was (model possible A), while to notice for the that other the insulation models, whichof the adopted roof and the of thepassive wall retrofitting, of the building it was with lowe 6 cmr. The thick analysis polyurethane highlighted panels a great (Figure difference9), and the in theremoval results of between the external the models window considered. (considered In in solution model D-E-F-G),3, it was possible improved to thenotice energy that performancethe insulation of ofthe the building roof and of of about the wall 80% comparedof the building to model with C, 6 whichcm thick had polyurethane a simple partition panels separating (Figure 9), the and EVOO the removalstorage roomof the from external the processingwindow (considered area and a shadingin model e ffD-E-F-G),ect produced improved by the the outdoor energy shading performance element. ofMoreover, the building models of about with the80% Canadian compared well to installation,model C, which such ashad model a simple G, did partition not allow separating lower energy the EVOOconsumption; storage room on the from contrary, the processing they increased area and the a energyshading consumption effect produced of aboutby the25%, outdoor especially shading in element.model F. Moreover,The possible modelsreason with could the beCanadian that the well Canadian installation, carried such external as model hot air G, well, did not exceeding allow lower 21 ◦C, energyinto the consumption; olive oil storage on room. the contrary, However, thethey most increased interesting the resultenergy was consumption that the insulation of about of the 25%, olive especiallyoil storage in walls model and F. roof The by possible means ofreason an 18 could◦C phase be that change the materialCanadian layer carried (model external H) did hot not air improve well, exceedingenergy saving 21 °C, compared into the olive to model oil storage F, which room. did notHowever, have any the PCM most layer. interesting This is result due to was the that fact the that insulationstone walls of havethe olive a high oil thermalstorage walls capacity and and, rooftherefore, by means anof increasean 18 °C inphase the buildingchange material walls thermal layer (modelinertia H) by did means not ofimprove PCM was energy negligible. saving Thecompared olive oil to storagemodel F, room which with did insulated not have walls any PCM and rooflayer. by Thismeans is due of a to 18 the◦C fact phase that change stone walls material have layer, a high separated thermal from capacity the processingand, therefore, area an and increase with external in the buildingwall shaded walls by thermal outdoor inertia shading by elementsmeans of (modelPCM was I) allowed negligible. an energyThe olive saving oil storage similar room to model with C. insulatedmodel E showedwalls and the roof best energyby means saving. of aIn 18 this °Cmodel, phase therechange were material some passive layer, separated retrofitting from solutions, the processingsuch as: a area simple and partition with external separating wall theshaded EVOO by storageoutdoor room shading from elements the processing (model area; I) allowed a shading an energyeffect producedsaving similar by the to outdoor model C. shading Model system;E showed roof the and best wall energy insulation saving. of In the this olive model, oil storage there were room somewith 6passive cm thick retrofitting polyurethane solutions, panels; such removal as: a simple of the externalpartition window; separating and the natural EVOO roof storage ventilation. room fromThe analysisthe processing of this modelarea; a showedshading an effect energy produced saving overby the 90% outdoor compared shading to the system; original roof olive and oil wall mill insulationmodel (model of the A). olive However, oil storage using room only with theseparation 6 cm thick ofpolyurethane the EVOO storage panels; room removal from of the the processing external window;area and and the insulationnatural roof of ventilation the roof and. The walls analysis of the of olive this oilmodel room showed allowed an an energy energy saving saving over of more90% comparedthan 80%. to the original olive oil mill model (Model A). However, using only the separation of the EVOO storage room from the processing area and the insulation of the roof and walls of the olive oil 6. Conclusions room allowed an energy saving of more than 80%. The retrofitting of ancient rural buildings needs a specific energy analysis because their structures 6.and Conclusions materials have anomalous behaviours compared to new buildings, which are used differently fromThe how retrofitting they were of in theancient past. rural Modern buildings building ne solutionseds a specific are not energy always analysis appropriate because to increase their structuresthe performance and materials of old traditionalhave anomalous rural buildings. behaviours This compared is often to due new to thebuildings, building which materials are used used differentlyin the past, from because how theythey havewere diinff theerent past. physical Modern properties building comparedsolutions are tomodern not always building appropriate materials. to increaseFor example, the performance the solution of withold traditional the use of rural PCM buildings. (solution This 7) showed is often good due to results the building in improving materials the usedthermal in the performance past, because in modern they have buildings different [9]. By ph meansysical ofproperties this material, compared it is possible to modern to obtain building a great materials.thermal inertia For example, for the envelope, the solution but, with in traditional the use of old PCM rural (solution buildings, 7) the showed walls ofgood stones results already in improvinghave a big the thermal thermal mass. performance The functions in modern of modern buildings rural buildings[9]. By means and foodof this processing material, it buildings is possible are to obtain a great thermal inertia for the envelope, but, in traditional old rural buildings, the walls of

Sustainability 2020, 12, 194 10 of 11 different from the past, because, lately, new food safety and quality laws have been introduced and the indoor environment characteristics also influence the chemical, physical and biological changes that take place during the production process, especially during the storage stage. In this paper, an ancient olive oil mill building was studied and different passive retrofitting strategies were considered and analysed. The study highlights the best efficient retrofitting strategy, which was the thermal insulation of the walls and roof of the storage room, because the old rural building had massive stone walls with high thermal capacity but low thermal resistance. Future work will evaluate the economic advantage and return on investment related to cost of retrofit measures.

Author Contributions: F.B. developed the methodology and wrote the paper, P.P. collaborated in developing the literature review, data acquisition and analysis under the supervision of F.B. All authors have read and agreed to the published version of the manuscript. Funding: This research was partly funded by project PON03PE_00090_2, in the framework of National Operational Programme (NOP) for Research and Competitiveness 2007–2013 of the Italian Ministry of Edu-cation, University and Research (MIUR) and Ministry of Economic Development (MiSE) and co-funded by the European Regional Development Fund (ERDF). Conﬂicts of Interest: The authors declare no conﬂict of interest.

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