Environmental assessment of solar thermal systems for the industrial sector

Accepted Manuscript Environmental assessment of solar thermal systems for the industrial sector Angeliki Kylili, Paris A. Fokaides, Andreas Ioannides, Soteris Kalogirou PII:

S0959-6526(17)33109-8

DOI:

10.1016/j.jclepro.2017.12.150

Reference:

JCLP 11545

To appear in:

Journal of Cleaner Production

Received Date: 6 August 2017 Revised Date:

8 December 2017

Accepted Date: 16 December 2017

Please cite this article as: Kylili A, Fokaides PA, Ioannides A, Kalogirou S, Environmental assessment of solar thermal systems for the industrial sector, Journal of Cleaner Production (2018), doi: 10.1016/ j.jclepro.2017.12.150. This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.

Environmental assessment of solar thermal systems for the industrial sector

ACCEPTED MANUSCRIPT

Title Environmental assessment of solar thermal systems for the

RI PT

industrial sector Authors

Angeliki Kylili A, Paris A. Fokaides A, Andreas Ioannides B, Soteris

Affiliations: Frederick University, School of Engineering,

M AN U

A

SC

Kalogirou C

7 Frederickou Str., 1036, Nicosia, Cyprus B

Johnsun Heaters Ltd

Voukourestiou 20, Strovolos, 2033, Nicosia, Cyprus C

Cyprus University of Technology, Department of Mechanical

Engineering and Materials Science and Engineering, Cyprus,

E-mail addresses:

TE D

30 Archbishop Kyprianou Str., 3036 Limassol, Cyprus

EP

Angeliki Kylili: [email protected] Paris A. Fokaides: [email protected]

AC C

Andreas Ioannides: [email protected] Soteris Kalogirou: [email protected]

Corresponding Author: Paris A. Fokaides: [email protected]

1

Environmental assessment of solar thermal systems for the industrial sector

ACCEPTED MANUSCRIPT

Environmental assessment of solar thermal systems for the industrial sector

RI PT

Abstract In Europe, about a third of the total final energy demand of the industrial sector is used for the generation of low temperature heat below 100 °C which could be satisfied by

SC

commercially available solar thermal applications. Although the technological readiness level of solar thermal technologies is currently in high levels, the recent energy mix

M AN U

data of industrial countries with high solar irradiation levels reveal that this potential still remains untapped. The key objective of this work is to quantify this unexploited potential and assess the environmental impact of industrial solar thermal systems (ISTS). Under this context, cradle-to-use Life Cycle Assessment (LCA) was conducted for the definition of the environmental performance of ISTS. A parametric analysis for

TE D

the application of ISTS at selected European sites with diverse solar potential was also implemented to investigate the impact of solar potential on the life cycle performance of the systems. Taking into consideration the findings on the potential of carbon savings

EP

from the application of ISTS and in relevance to the European Union Emissions Trading System (EU ETS), scenarios of ISTS penetration and monetization into the

AC C

industrial sector have also been developed. The findings of this work can be used by policy- makers as guidelines for the development of national strategic plans and financial incentives for the promotion of large-scale industrial solar thermal applications. The implementation of a parametric assessment on the environmental performance of ISTS for specific European geographical locations of diverse solar potential enabled the development of a ‘Life Cycle Produced to Consumed Energy’ Ratio, which indicated that applications located at lower latitudes (in the northern hemisphere) can achieve greater life cycle energy and carbon savings than ISTS

2

Environmental assessment of solar thermal systems for the industrial sector

ACCEPTED MANUSCRIPT

applications found higher in latitude. In particular, large- scale ISTS applications were found to achieve energy and carbon savings ranging from 35 – 75 GJ and 2 – 5 tonnes of CO2 per kWth, depending on the geographical location.

RI PT

Keywords Solar thermal system, flat plate collector, industrial sector, Life Cycle Assessment, Emissions Trading System

Nomenclature

Unit [kg Sb- equiv.]

SC

M AN U

AC C

AP CWHS EP EPBT ESTIF EU ETS FAETP FiT GHG GWP HTP IEA ISTS LCA LCC LCIA LCI MAETP NAP NRER ODP POCP PV RES TETP

TE D

ADPF

Description Abiotic Resource Depletion Potential for elements Abiotic Resource Depletion Potential of Fossil Fuels Acidification Potential Conventional Water Heating Systems Eutrophication Potential Energy Payback Time European Solar Thermal Industry Federation European Emission Trading System Fresh-Water Aquatic Ecotoxicity Potential Feed-in Tariff Greenhouse Gases Global Warming Potential Human Toxicity Potential International Energy Agency Industrial Solar Thermal Systems Life Cycle Assessment Life Cycle Costing Life Cycle Impact Assessment Life Cycle Inventory Marine Aquatic Ecotoxicity Potential National Action Plan Non- Renewable Energy Resources Ozone Depletion Potential Photochemical Oxidant Creation Potential Photovoltaic Renewable Energy Sources Terrestric Ecotoxicity Potential

EP

Abbreviation ADPE

3

[MJ]

[kg SO2- equiv.] [kg phosphate- equiv.] [kg DCB- equiv.] [kg CO2- equiv.] [kg DCB- equiv.] [kg DCB- equiv.] [MJ] [kg R11- equiv.] [kg ethene- equiv.] [kg DCB- equiv.]

Environmental assessment of solar thermal systems for the industrial sector

ACCEPTED MANUSCRIPT

1. Introduction While solar thermal technologies are widely used for domestic applications across Europe, their application in the industrial sector is still at low levels. The generation of

RI PT

process heat from solar thermal systems has an enormous potential and this can satisfy a substantial amount of heat demand in industrial processes. Particularly in Europe, about 27 % of the total final energy demand is heat consumed by the industry, of which about 30 % occurs at low temperature levels below 100 °C and further 27 %

SC

between 100 °C and 400 °C (low to medium temperatur e) [1]. In many EU countries, a significant percentage of the heat demand, which concerns the lower temperature

M AN U

range below 100 °C, can be generated by commerciall y available solar thermal systems. Medium temperature levels up to 200°C have been attained using ultra-high vacuum flat plate collectors and vacuum tube collectors with concentrators, while solar concentrators including parabolic trough and Fresnel designs can produce pressurised

TE D

steam at temperatures up to 400°C. Currently, appro ximately 40% of industrial primary energy consumption is covered by natural gas and approximately 41% by petroleum. This means that there is a technical potential to provide around 15 EJ of solar thermal

EP

heat by 2030, while the share of solar thermal deployed in the industrial sector could reach 33% [2]. This is also anticipated to significantly support the industrial sector in

AC C

achieving its Greenhouse Gases (GHGs) emission mitigation under the European Union Emissions Trading System (ETS), and also contribute in meeting Europe’s 2020 energy and climate targets. However at the moment, not many installations for process heat have collector areas exceeding 1000 m2 in Europe [3]. The main focus of this study is the implementation of the Life Cycle Assessment (LCA) of

Industrial Solar Thermal Systems (ISTS), considering the ‘cradle-to-use’

environmental impact of the different components that make up the systems. The findings of the environmental performance of ISTS are evaluated with respect to the

4

Environmental assessment of solar thermal systems for the industrial sector

ACCEPTED MANUSCRIPT

competitive conventional water heating systems (CWHS), whereas a parametric LCA analysis for specific European geographical locations of diverse solar potential is also conducted. Based on the findings of the potential of carbon savings from the

RI PT

application of ISTS and in relevance to the European Emissions Trading System (ETS), scenarios of ISTS penetration and monetization into the industrial sector are also developed and presented. This work concludes with the definition of appropriate incentives that could be adopted for the ISTS penetration in diverse locations within

2. Literature Review

M AN U

SC

Europe.

2.1. Industrial application of solar water heating

The application of solar thermal systems for water heating is predominantly suitable for industries that utilise water temperature within the low temperature range of 40°C to

TE D

80°C and have low energy requirements, which can be satisfied partly by solar thermal systems. Such industries include the food industry, agro-industries, textiles, the chemical industry, and the beverage industry [4],[5]. Due to their low cost and simple

EP

construction, Muneer et al. [6] proposed the introduction of built-in-storage water heaters, units that combine flat-plate collector and storage tank in one system, for

AC C

application in the textile industry. The work included comparative thermal, economic, and environmental performance analyses of a plain design and new built-in-storage water heater design by introducing fins within its construction; the finned-type system outperformed the plain design. Using the model of an Austrian dairy plant, Schnitzer et al. [7] investigated the potential and the feasibility of exploiting solar thermal energy for heat processes in industry. A number of processes within the dairy industry, which ran within the low temperature range such as cheese production and cleaning processes, were deemed suitable utilising warm and hot water from solar energy. A solar field of

5

Environmental assessment of solar thermal systems for the industrial sector

ACCEPTED MANUSCRIPT

1000 m2 was demonstrated to achieve annual natural gas savings of 85 000 m3 and carbon savings of 170 tons of CO2, while in less than three years of implementation there was a return on the investment. Kalogirou and Tripanagnostopoulos [8]

RI PT

introduced a new hybrid photovoltaic/thermal system for low temperature industrial application, which was assessed using the TRNSYS tool. The conclusions drawn were that although a non-hybrid PV system produced 25% more electricity, the specific system has added advantage as it also covered a great percentage of the thermal

SC

energy required for the industrial process.

M AN U

Beyond this application, potential has also been identified for solar thermal energy at a medium and medium–high temperature level that satisfies the temperature requirements of solar industrial process heat applications (60°C to 260°C) [5][9][10]. The viability of using parabolic trough collectors for industrial heat generation in Cyprus has been examined by Kalogirou [5]. Considering the load of the industrial application,

TE D

the optimum collector area, collector flow rate and storage tank size were determined and the system was demonstrated to satisfy half of the annual load, achieving annual energy savings of 896 GJ and carbon savings of 208 tons of CO2 equivalent. A

EP

parametric analysis on the load use pattern also revealed that greater savings were achieved with larger loads, concluding to the viability of solar thermal systems in higher

AC C

energy consumption industries. In a subsequent study and using the same methodology, Kalogirou [9] examined the viability of additional solar thermal systems for providing industrial process- heat, varying from the simple stationary flat-plate to movable parabolic trough ones. The results indicated that the energy generation of these systems ranged between 550 to 1100 kWh/ m2 a, depending on the type of solar collector. A novel methodology, called design space approach, has been proposed by Kulkarni et al. [11][12] for the design and optimization of flat plate solar collector based systems and also of concentrating solar collector based systems. The proposed

6

Environmental assessment of solar thermal systems for the industrial sector

ACCEPTED MANUSCRIPT

methodology was initially restricted to storage water temperature of less than 100˚C [11], while in a subsequent study [12] the methodology was extended to be applicable for medium temperature industrial applications, where hot water needs to be

RI PT

pressurized. In the design space approach a mathematical model was built for generation of the design space, where the design variables of concern were the collector area, the storage volume, the solar fraction, the storage mass flow rate and the heat exchanger size. The final design of the overall system was selected based on

SC

economic optimization. The proposed methodology was demonstrated through a case

M AN U

study of a dairy plant, where it was indicated that 23% reductions in the total system cost may be realised as compared to the existing design.

2.2. LCA of solar water heating

Solar thermal systems are exploiting a renewable energy source essentially emitting

TE D

zero emissions during their life cycle operation phase. This has led to the implementation of a considerable number of LCA studies, whose focus is on the quantification of the environmental impact of the systems throughout their life cycle. In

EP

a recent study [13], 32 different types of solar water heating systems were studied for meeting the daily heating energy for domestic hot water of 2 dwellings and 2 hotels

AC C

located in the region of Aragon in Spain during a time period of 20 years. The use of biomass as fuel for the auxiliary system in solar water heating systems has demonstrated the greatest performance, in terms of kilograms of CO2 equivalent, while at the same time high value of energy payback time (EPBT) was obtained as a result of the biomass being the fuel with the lowest environmental impact and associated embodied energy. Several researchers have employed LCA related to the environmental impact of two types of solar thermal systems, traditionally used for domestic water heating, namely

7

Environmental assessment of solar thermal systems for the industrial sector

ACCEPTED MANUSCRIPT

flat plate and evacuated tube collectors [14][15][16]. The results of Hang et al. [14] indicated that the flat-plate solar water heating systems using natural gas auxiliary heater was the best performing system among all the investigated types of auxiliary

RI PT

systems and locations, while Greening and Azapagic [16] indicated the better performance of evacuated tube collectors in regions with low solar irradiation, such as the UK. Regarding the study of Carlsson et al. [15], a solar heating system with polymeric solar collectors was compared with the two aforementioned solar heating

SC

systems, by employing LCA and Life Cycle Costing (LCC) methodologies. The solar

M AN U

heating system with polymeric solar collectors outperformed the more traditional system with respect to climatic and environmental performance. It is also worth mentioning that the impact of the type of auxiliary heating and geographical location on the performance of the systems was previously investigated by De Laborderie et al. [17]. In this work, the systems’ performances were analysed as case studies both for

TE D

temperate climates and for tropical climates.

Otanicar and Golden [18], Lamnatou et al. [19] [20], Comodi et al. [21], and Carnevale et al. [22] conducted the LCA of novel solar thermal collector concepts. In particular,

EP

Otanicar and Golden [18] compared the environmental and economic impacts of using nanofluids to enhance solar collector efficiency and Lamnatou et al. [19][20] developed

AC C

the environmental profile of a patented building-integrated solar thermal collector. The environmental impact of a solar thermal system with unglazed solar collectors was compared to a traditional system with glazed panels by Comodi et al. [21], while Carnevale et al. [22] assessed the environmental performance of a solar thermal collector with four types of photovoltaic modules, i.e., mono-Si, multi-Si, CdTe and CISe, with the aim of supplying additional helpful elements for promoting such technologies at residential scale.

8

Environmental assessment of solar thermal systems for the industrial sector

ACCEPTED MANUSCRIPT

While the majority of studies performed cradle-to-gate LCA, a few have given important weight on the manufacturing life cycle stage of solar water heating systems. Martinopoulos et al. [23] investigated the influence from the use of different materials

RI PT

and techniques in the manufacturing of solar flat plate collectors used in the domestic scale, whereas LCA was also employed by Koroneos and Tsarouhis [24] for the evaluation of the impacts of the energy and raw materials use including waste disposal for establishing efficient and practical environmental improvements, based on the

SC

rational use of raw materials and energy. Additionally, in the work of Koroneos and

M AN U

Nanaki [25], the focus is on the environmental impact associated with the production and utilization of solar energy systems and in particular to the atmospheric emissions of a solar water heating system during its life span.

A few studies have also investigated the life cycle performance of solar thermal systems from an environmental perspective, using the LCC methodology. The work of

TE D

Hang et al. [38] calculated the LCC payback for solar water heating systems to vary from 4 to 13 years depending on the geographical location and type of solar collectors by using the conventional electrical water heating system as the reference case. In

EP

Carlsson et al. [15], where a solar heating system with polymeric solar collectors was compared with two equivalent solar heating systems (flat plate solar collectors and

AC C

evacuated tube solar collectors) by employing both LCA and LCC, the economic analysis indicated that despite the environmental advantage of the novel system, in terms of costs per amount of solar heat collected, the differences between the three types of collector systems were small, considering the given energy prices and environmental tax rates.

9

Environmental assessment of solar thermal systems for the industrial sector

ACCEPTED MANUSCRIPT

2.3. European policy on support schemes for the promotion of RES and Energy Efficiency The European Union is taking action in several areas to meet its climate and energy

RI PT

targets under the 2020 package. The Renewable Energy Directive [26] established the overall policy for the production and promotion of renewable energy, requiring the EU to satisfy at least 20% of its total energy demand through the exploitation of Renewable

SC

Energy Sources (RES). This objective is anticipated to be achieved through the fulfilment of national renewable targets, set by each of the Members States in their

M AN U

National Action Plans (NAPs). In the Directive, it is acknowledged that each Member State has different renewable energy potentials, and thus in order to meet its national targets, tailored support schemes and other measures have to be developed and implemented. The rationalisation of national support schemes is also considered important in successfully meeting the targets, so as the investor confidence is

TE D

maintained and schemes are effectively implemented. Accordingly, for the proper functioning of national support schemes, it is fundamental that these can be controlled and fit the local renewable energy potentials. Examples of support schemes that have

EP

been adopted by Member States involve investment aid, tax exemptions or reductions, tax refunds, as well as renewable energy obligation support schemes such as green

AC C

certificates, and direct price support schemes including feed-in tariffs (FiTs), premium payments, and competitive auctions. However, in several cases support schemes that have implemented successfully in one country, were not so successful in another country [27][28].

As far as the contribution of the industrial sector for meeting the climate and energy targets is concerned, the EU has established a support scheme, the EU Emissions Trading System (EU ETS), which has proven extremely successful and now it is in its third trading period [29][30]. EU ETS is the EU's key tool for cutting greenhouse gas

10

Environmental assessment of solar thermal systems for the industrial sector

ACCEPTED MANUSCRIPT

(GHG) emissions from large-scale facilities in the power, industry and aviation sectors. It is a ‘cap and trade’ system, where the total volume of GHG emissions from installations and aircraft operators, which are responsible for 45% of European GHG

RI PT

emissions, is capped. The relevant legislation creates allowances which are essentially rights to emit GHG emissions equivalent to the global warming potential of one tonne of carbon dioxide equivalent (tCO2 – eq.). The level of the cap, which tightens over time, determines the number of allowances available in the whole system. The scheme

SC

allows the trading of emission allowances with the purpose of keeping the total

M AN U

emissions of the installations and aircraft operators within the cap and ensuring emissions are reduced where it is more cost-effective. As a result, trading allows the carbon price to meet the desired target.

3. Methodology

TE D

3.1. Methodology overview

The methodology that is followed in this work is based on the implementation of LCA on Industrial Solar Thermal Systems (ISTS), which incorporated the environmental

EP

assessment of the different components that make up the systems including the flat plate collectors, storage tank and other auxiliary components. The definition of the

AC C

environmental impact of ISTS enables the comparison with CWHS, as well as the conduction of a parametric analysis for specific densely populated European locations of diverse solar potential. Taking into consideration the findings on the potential of carbon savings from the application of ISTS and in relevance to the European Emissions Trading System (ETS), scenarios of ISTS penetration and monetization into the industrial sector were developed. In view of that, the study includes to the definition of appropriate incentives for ISTS penetration for diverse locations within Europe. The methodology to be followed in this study is illustrated in Figure 1.

11

Environmental assessment of solar thermal systems for the industrial sector

ACCEPTED MANUSCRIPT

Please insert Figure 1 here

RI PT

3.2. Life Cycle Assessment Scope and Inventory The primary objective of this work was to assess the environmental impact of solar thermal water heating systems for industrial applications This objective is achieved

SC

through the adoption of the standardised LCA approach, provided by the ISO 14040 series, and the employment of one of the most well- established LCA tools currently

M AN U

available ― GaBi software [31][32][33]. The investigated solar thermal water heating systems were pre-engineered to satisfy the temperature requirements of industrial processes concerning low temperature hot water up to 100 °C [10]. Taking into consideration the installed capacity of existing ISTS which exploit flat plate collector technology for water heating purposes [34], four (4) functional units have been defined

TE D

(Table 1).

EP

Please insert Table 1 here

In this study, a cradle to use analysis was implemented. The system boundaries

AC C

included the solar thermal system, in terms of raw materials extraction, manufacturing, transportation, assemble and maintenance. The use phase of the solar thermal system was considered, while the end of life management of its components was excluded. The considered life cycle stages of the study are given in Table 2. The system boundaries are also illustrated in Figure 2.

Please insert Table 2 here Please insert Figure 2 here

12

Environmental assessment of solar thermal systems for the industrial sector

ACCEPTED MANUSCRIPT

With respect to the investigated ISTSs, the considered functional units included the systems which are comprised from the solar collectors, storage tank, mounting

RI PT

equipment, pipes, hydraulic components, auxiliary heating and the solar fluid. The life cycle inventory (LCI) is provided in Table 3. The data for the development of the LCI has been obtained from the manufacturers and/ or importers of the components that make up the solar thermal systems; whereas for those components primary data were

SC

not available, secondary data from well-established LCI databases has been used.

M AN U

More specifically, LCI data for the solar collectors, storage tank, mounting equipment, pipework, insulation and solar fluid has been calculated based on information provided by the manufacturers of the systems (Johnsun Heaters Ltd). The technical characteristics of the systems and other relevant information used for the implementation of this study have been obtained through datasheets, as well as series

TE D

of personal communications with the company. Additionally, EcoInvent ― one of the most established LCI databases― has been employed for the development of the LCI

EP

of the pump required for the operation of ISTS.

AC C

Please insert Table 3 here

The assumptions made for the environmental analysis are the following:


Cyprus was considered as the reference geographical area for the

manufacturing of the solar thermal system. The origin of the different system components was considered as follows [35]:


Absorber Plate: Germany




Back cover and framework: Egypt




Headers and risers: Bulgaria

13

Environmental assessment of solar thermal systems for the industrial sector

ACCEPTED MANUSCRIPT







Glass wool and tempered glass: Greece




EPDM: Cyprus

A parametric investigation of the impact of the distance between the assembly

RI PT

and the installation point was not considered as a requirement, as the environmental impact of this parameter was found to be negligible.


The life span of the solar thermal system was assumed to be 20 years.




The use phase of the system included the fossil fuel combustion for auxiliary

SC

heating, while its maintenance included the annual drainage and refilling of the

M AN U

solar fluid over its lifetime.


Propylene glycol was considered as the solar fluid.




The auxiliary heating was assumed to be through fossil-fuelled boiler, representing a CWHS. The manufacturing of the auxiliary heating source (boiler) was also considered. The capacity of the boiler for each functional unit

TE D

is provided in the supplemental material of the study.

The findings of the LCA regarding the quantification of the environmental impact of the investigated ISTS were evaluated with respect to the environmental performance of

EP

equivalent capacity of compatible water heating systems, ie., fossil-fuelled boilers. The performance of the ISTS under investigation was also assessed under diverse

AC C

climatic conditions, given that its performance would be affected by the solar potential of the installation location. The rationale of the choice of the specific locations was justified in [36]. For each considered location, the energy yield of the four considered capacities was defined, by employing the TSOL software, [37]. For the calculation of the energy yield of any solar thermal system, TSOL requires the input of a set of specific system design parameters. Accordingly, detailed information concerning the design parameters of the ISTS considered for this study, as well as their energy yield under diverse locations is provided in the supplemental material of the study. The

14

Environmental assessment of solar thermal systems for the industrial sector

ACCEPTED MANUSCRIPT

annual energy contribution of the ISTS and the auxiliary hot water system per kWth, for a system with a nominal capacity of 1100 kWth, for each considered location is presented in Figure 3.

RI PT

Please insert Figure 3 here

3.3. LCC and Support Schemes

SC

In terms of this study the application of potential support schemes for ISTS was also considered. A support scheme refers to any instrument, scheme or mechanism applied

M AN U

by a country that promotes the use of energy from renewable sources by reducing the cost of that energy, increasing the price at which it can be sold, or increasing the volume of such energy purchased. This may include investment aid, tax exemptions or reductions, tax refunds, renewable energy obligation support schemes and direct price support schemes [26]. In terms of this study, potential investment aids have been

TE D

suggested.

The definition of potential support schemes within this study was defined by considering the equivalent cost of carbon savings from the application of ISTS and in

EP

relevance to the EU ETS. The calculation of the carbon monetary value, the price of carbon was set at 10.32 [€/ tn CO2], representing the average cost for carbon since

AC C

January 1st, 2008 [38]. The chosen date indicates the start of the Second Trading Period of the EU ETS. The costing of the investigated ISTS was performed based on price indicators retrieved from ESTIF [3] as well as based on LCC principles described in [39] [40]. For the development of the scenarios of ISTS penetration, as well as the implementation of the LCC, actual data of the total final consumption of the industrial sector for each of the investigated locations have been retrieved from the International Energy Agency and are presented in Figure 5 [41]. This work concludes to incentives’

15

Environmental assessment of solar thermal systems for the industrial sector

ACCEPTED MANUSCRIPT

recommendations for the development of support schemes of ISTS in the considered energy mixes.

RI PT

Please insert Figure 4 here

4. Results and Discussion

4.1. Life Cycle Impact Assessment (LCIA) of Industrial Solar Thermal

SC

Systems (ISTS)

The Life Cycle Impact Assessment (LCIA) results have indicated a linear relationship

M AN U

between the environmental impact results and the size of the ISTSs under examination, denoting that the environmental performance of ISTS is directly proportional to its size. The LCIA results, generated by GaBi software and provided in Table 4 Life Cycle Impact Assessment (LCIA) results per kWth of ISTS , show the potential of environmental impact per installed kWth of ISTS. A more

TE D

detailed breakdown of the environmental impact of each of the considered systems is provided in the supplemental material.

here

AC C

EP

Please insert Table 4 Life Cycle Impact Assessment (LCIA) results per kWth of ISTS

The impact of the life cycle stages to each of the environmental impact categories are illustrated in Figure 5. Overall, the results demonstrate that the life cycle phases of the investigated solar thermal system which are the most detrimental to the environment in ascending order are the raw material extraction, the system manufacturing phase, and the use phase. The impact of the raw material extraction and the system manufacturing phase contribute to more than 84% of the total in the categories of ozone depletion,

16

Environmental assessment of solar thermal systems for the industrial sector

ACCEPTED MANUSCRIPT

depletion of elements, as well as the ecotoxicity of human health, and marine and terrestric environments. As a result of the fossil fuel combustion of the auxiliary heating system for the generation of hot water, the use phase is presented to have a principal

RI PT

contributing role in the potential for global warming, acidification, eutrophication, depletion of fossils and the creation of photochemical ozone in the troposphere, ranging from 67% to 81%. Regarding the freshwater ecotoxicity potential (FAETP) category, the two phases carry equal weighting. The installation of the system is also

SC

worth noting, contributing by 9% in the acidification potential, by 6% in the terrestric

M AN U

ecotoxicity potential, and by 5% in the photochemical ozone creation potential. Regarding the rest of the phases included in the system boundaries of this work, namely the transportation of the system and system components and the maintenance of the system, their contribution to the totals are negligible.

TE D

Please insert Figure 5 here

The environmental impact of ISTS was also comparatively assessed with the CWHS of

EP

equivalent system output, taking into consideration the same system boundaries. The results on the environmental impact of the ISTS on the different impact categories

AC C

indicated that the potential impact increases proportionally to the system size. The results of the comparative assessment between the two competitive technologies for the location of Athens are presented in Table 5 Comparative Life Cycle Impact Assessment (LCIA) results for ISTS and Conventional Water Heating Systems in Athens (FU1) . The potential of ISTS is presented to be less than the one third of its conventional equivalent system for the categories of climate change, acidification, eutrophication, depletion of fossil fuels and photochemical ozone creation. The potential in the

17

Environmental assessment of solar thermal systems for the industrial sector

ACCEPTED MANUSCRIPT

respected categories for the conventional system can be largely related to the fossil fuel combustion during its manufacturing and use phase. However, the comparative analysis results also reveal the significant pressure to the environment caused by

RI PT

manufacturing of the ISTS, especially in terms of abiotic depletion of elements and ecotoxicity of the human health. For the specific categories, the potential of ISTS is considerably higher than its conventional equivalent system, by a factor of 400 and 30,

SC

respectively.

M AN U

Please insert Table 5 Comparative Life Cycle Impact Assessment (LCIA) results for ISTS and Conventional Water Heating Systems in Athens (FU1) here

By taking into consideration the life cycle phases within the defined system boundaries,

TE D

the non-renewable energy resources and carbon dioxide balances for both systems have been extracted from GaBi software. The life cycle energy resources and carbon

EP

dioxide balances for the investigated functional units are presented in Figure 6.

AC C

Please insert Figure 6 here

4.2. Parametric Life Cycle Impact Assessment (LCIA) results for diverse locations

To enable the definition of the impact of the location of the ISTS, the environmental impact potential for the considered categories are provided per kWth of ISTS. In view of that, the results of the parametric LCIA for diverse locations on the considered environmental impact categories are presented in Table 6 Life Cycle Impact Assessment results

18

Environmental assessment of solar thermal systems for the industrial sector

ACCEPTED MANUSCRIPT

per kWth of ISTS at diverse European locations . The differences in the LCIA results can be attributed to the following life cycle phases: The energy consumed during the ISTS installation phase




The transportation of the ISTS and auxiliary components to the European sites




The energy consumed for the generation of hot water from the auxiliary system

RI PT




during the use phase


The energy consumed for the maintenance of the ISTS

SC

However, it is evident from Figure 5, as well as the LCIA values provided in the supplementary material, that the environmental impact from the transportation of the

M AN U

ISTS and auxiliary components to the European sites, as well as the energy consumed for the installation and maintenance of the ISTS is negligible and is not accounted for these differences. The overall trend of the LCA parametric analysis indicates that the environmental burden of ISTS found in locations of lower solar potential is higher than

TE D

the systems’ located in southern latitudes. The reasoning directs to the use phase of the system and the fact that the ISTS located in areas of high solar potential, ie., Athens and Barcelona can generate higher energy yields for the supply of hot process

EP

water, while the use of the auxiliary system along with the fossil fuel consumption is substantially reduced. In fact, for the cases of Copenhagen and Oslo, the auxiliary

AC C

heating system contributes significantly more for the supply of hot water than the ISTS, on an energy yield per annum basis (Figure 3). It is also worth noting that another factor that was indicated to play a significant role in the results is the national energy mix. This is evident when allowing for the environmental performance of ISTS located in Oslo. While the application of ISTS in Copenhagen can provide greater energy yields for the supply of hot water, as a result of greater solar potential, the environmental performance of a comparable application in Oslo is superior in the majority of the

19

Environmental assessment of solar thermal systems for the industrial sector

ACCEPTED MANUSCRIPT

considered categories. This difference should be traced back to the environmental impact associated with the lower primary to end energy conversion factor of Norway.

RI PT

Please insert Table 6 Life Cycle Impact Assessment results per kWth of ISTS at diverse European locations here

SC

The overall non-renewable energy resources and carbon dioxide emissions for the considered sites, as well as the savings that can be achieved when compared to

M AN U

CWHS are presented in Table 7 Life Cycle energy and carbon emissions savings per kWth of ISTS at diverse European locations . It is evident that the location has a decisive effect on the energy and carbon savings that can be achieved by large-scale ISTS applications; the results show that energy

TE D

and carbon savings can range between 35 – 75 GJ and 2 – 5 tonnes of CO2 per kWth, respectively. However, the impact of location on the energy performance of ISTS application is more profound by the ‘Life Cycle Produced to Consumed Energy’ Ratio,

EP

developed under this study (Figure 7). For the range of latitude from 35˚ to 60˚, the figure illustrates the strong inverse relationship between latitude and the Ratio: a higher

AC C

latitude of location of an ISTS application denotes a lower the ‘Life Cycle Produced to Consumed Energy’ Ratio and consequently a reduced system energy lifetime performance.

Please insert Table 7 Life Cycle energy and carbon emissions savings per kWth of ISTS at diverse European locations here Please insert Figure 7 here

20

Environmental assessment of solar thermal systems for the industrial sector

ACCEPTED MANUSCRIPT

4.3. Scenarios of Industrial Solar Thermal Systems (ISTS) penetration The results of the LCC of the considered ISTS are provided in Table 4 Number of 700 installations

and

saved

carbon

monetary

value

RI PT

kWth

per percentage of ISTS penetration into considered energy mixes

, where the saved carbon monetary value and the required number of ISTS

SC

applications of 700 kWth per penetration percentage are indicated. The values differentiate depending on the total final consumption of the industry of each country

M AN U

(Figure 5), as well as on the potential energy saving per installed kWth. Denmark is presented with the lowest number of required capacity of ISTS applications of 700 kWth to satisfy the national demand (i.e., total final consumption of the industry of each country ― Figure 5), as well as the lowest saved carbon monetary value per percentage of ISTS contribution into its energy mix. By considering the findings of

TE D

Table 4 Number of 700 kWth installations and saved carbon monetary value per percentage of ISTS penetration into considered energy mixes , policy makers can be guided through for providing appropriate values of financial

AC C

scheme.

EP

incentive for large- scale ISTS applications, depending on the chosen national support

Please insert Table 4 Number of 700 kWth installations and saved carbon monetary value

per percentage of ISTS penetration into considered energy mixes here

21

Environmental assessment of solar thermal systems for the industrial sector

ACCEPTED MANUSCRIPT

5. Conclusions While solar thermal technologies are widely used for domestic applications across Europe, solar heat for industrial processes is still a niche market. The key objective of

RI PT

this work was to quantify the untapped potential of solar thermal in industrial applications and provide recommendations for the development of financial incentives for the promotion of the technology. For this purpose, the definition of the environmental performance ISTS has been performed through the implementation of

SC

LCA studies. The LCA results demonstrated that the life cycle phases of the investigated solar thermal systems which are the most detrimental to the environment

M AN U

include the raw material extraction and the system manufacturing phase, as well as the use phase. The raw material extraction and the system manufacturing phases contributed to more than 85% of the total impact in the categories of ozone depletion, depletion of elements, and the ecotoxicity of human health, and marine and terrestric

TE D

environments. The use phase was found to be the main contributor in the depletion of fossils and the creation of photochemical ozone impact categories, as a result of the fossil fuelled combustion of the auxiliary heating system for the generation of hot water.

EP

The implementation of a parametric assessment on the environmental performance of ISTS for specific European geographical locations of diverse solar potential enabled

AC C

the development of a ‘Life Cycle Produced to Consumed Energy’ Ratio, which indicated that applications located at lower latitudes (in the northern hemisphere) can achieve greater life cycle energy and carbon savings than ISTS applications found higher in latitude. Lower latitude locations have higher solar potential generating higher energy yields for the supply of hot process water, whereas the use of the auxiliary system is substantially reduced. In particular, large- scale ISTS applications were found to achieve energy and carbon savings ranging from 35 – 75 GJ and 2 – 5 tonnes of CO2 per kWth, depending on the geographical location. The Ratio can also be used to

22

Environmental assessment of solar thermal systems for the industrial sector

ACCEPTED MANUSCRIPT

support decision-making by policy-makers throughout the process of renewable energy support schemes’ development. Especially in the case of large countries or unions that extend through several climatic zones, the ‘Life Cycle Produced to Consumed Energy’

RI PT

Ratio can provide significant guidance in setting realistic incentives in relation to local available potential. The parametric analysis also enabled the development of scenarios of ISTS penetration into the industrial sector in relation to the EU ETS, as well as the definition of the carbon monetary value at selected Member States. The evaluation of

SC

the required capacity of large- scale ISTS applications to satisfy the desired percentage

M AN U

of the national industrial demand for hot water is supported, by taking into consideration the carbon monetary value and the geographical location of application. The findings of this work can be exploited by European policy-makers as guidelines for the development of national strategic plans and investment aids for the promotion of

AC C

EP

TE D

large-scale solar heat water generation applications for industrial processes.

23

Environmental assessment of solar thermal systems for the industrial sector

ACCEPTED MANUSCRIPT

M AN U

SC

RI PT

Figures

AC C

EP

TE D

Figure 1 Graphic representation of the methodology of the study

24

Environmental assessment of solar thermal systems for the industrial sector

AC C

EP

TE D

M AN U

SC

RI PT

ACCEPTED MANUSCRIPT

Figure 2 Life Cycle Assessment – System Boundaries (T: Transportation)

25

Environmental assessment of solar thermal systems for the industrial sector

TE D EP

5

Figure 3 Energy contributions of the ISTS and the auxiliary conventional water heating systems in investigated sites

AC C

1 2 3 4

M AN U

SC

RI PT

ACCEPTED MANUSCRIPT

26

Environmental assessment of solar thermal systems for the industrial sector

ACCEPTED MANUSCRIPT

Spain

M AN U

SC

RI PT

Greece

Germany

AC C

6

EP

TE D

Italy

27

Environmental assessment of solar thermal systems for the industrial sector

ACCEPTED MANUSCRIPT

Norway

7 8 9

M AN U

SC

RI PT

Denmark

Figure 4 Energy consumption of the industrial sector (2014) for investigated sites

AC C

EP

TE D

10

28

Environmental assessment of solar thermal systems for the industrial sector

M AN U

SC

RI PT

ACCEPTED MANUSCRIPT

11

TE D EP

14

Figure 5 Life Cycle Impact Assessment per kWth of ISTS located in Athens

AC C

12 13

29

Environmental assessment of solar thermal systems for the industrial sector

M AN U

SC

RI PT

ACCEPTED MANUSCRIPT

15

Figure 6 Energy resources consumption and carbon dioxide emissions

18

for hot water systems located in Athens (FU1, FU2, FU3, FU4)

EP AC C

19

TE D

16 17

30

Environmental assessment of solar thermal systems for the industrial sector

M AN U

SC

RI PT

ACCEPTED MANUSCRIPT

20 21 22

Figure 7 ‘Life Cycle Produced to Consumed Energy’ Ratio’

AC C

EP

TE D

23

31

Environmental assessment of solar thermal systems for the industrial sector

ACCEPTED MANUSCRIPT

Tables Table 1 LCA Functional Units – ISTS

Installed thermal power [kWth] Installed collector area [m²], gross Aperture area [m²] Number of solar collectors Number of water storage tanks

Functional Units (FU) FU2 FU3 210 525 300 750 275 689 123 308 28 69

Table 2 Life Cycle Stages – ISTS

M AN U

SC

Description Raw materials extraction and processing Transport of raw materials to the solar system components manufacturers Manufacturing of solar system components Transport of solar system components to assembly point Assembly of solar thermal system Transport of solar thermal system to installation point Installation of solar thermal system Use of solar thermal system Maintenance of solar thermal system

AC C

EP

TE D

Stage A1 A2 A3 A4 A5 A6 A7 B1 B2

FU4 700 1000 918 410 92

RI PT

FU1 70 100 92 41 9

32

Environmental assessment of solar thermal systems for the industrial sector

ACCEPTED MANUSCRIPT

Table 3 Life Cycle Inventory – ISTS Life Cycle Stage

Input Solar Collector

Value

Life Cycle Stages A1 - A3

Transport distance [km] Transport distance [km] Transport distance [km] Transport distance [km] Transport distance [km] Transport distance [km] Hot Water Storage Tank

Life Cycle Stages A1 - A3

Copper [kg] Galvanized steel [kg] Polyurethane foam [kg] Copper [kg]

FU3 737 9250 1991 401 1119 1115 1338 5967

FU4 981 12314 2650 533 1489 1484 1781 7943

2522 482 1226 918 20 918

FU1 365 393 74 152

FU2 1135 1223 232 473

Transport distance [km] Auxiliary Components

TE D

Hot water cylinder Casing vessel Insulation Coil heat exchanger Life Cycle Stage A4 Hot water storage tank

FU2 294 3694 795 160 447 445 534 2383

RI PT

Risers Tempered glass Life Cycle Stage A4 Absorber plate Back cover and framework Headers and risers Insulation (glass wool) Insulation (EPDM) Tempered glass

FU1 98 1231 265 53 149 148 178 794

SC

Insulation

Copper [kg] Aluminium [kg] Aluminium [kg] Copper [kg] Glass wool [kg] EPDM [kg] Copper [kg] Float flat glass [kg]

M AN U

Absorber plate Back cover Framework Headers

FU3 2797 3015 571 1167

FU4 3730 4020 761 1556

2522

Life Cycle Stages A1 - A3

Copper [kg] Polyethylene [kg] Propylene glycol [kg] Galvanized steel [kg] Aluminium [kg] Cast iron [kg] Copper [kg] Paint [kg] Hot rolled steel [kg] Synthetic rubber [kg]

Pump

AC C

EP

Pipework Insulation Solar fluid Mounting equipment

Life Cycle Stage A4 Pipework Insulation Solar fluid Mounting equipment Pump

Transport distance [km] Transport distance [km] Transport distance [km] Transport distance [km] Transport distance [km]

33

FU1 11 18 819 334 0,03 1 0,25 0,05 1 0,01

FU2 33 53 2456 1003 0,05 2 0,40 0,08 2 0,02

FU3 82 133 6150 2512 0,11 3 0,68 0,16 5 0,04 1226 1226 10 482 2522

FU4 109 177 8186 3344 0,14 6 1,35 0,20 6 0,05

Environmental assessment of solar thermal systems for the industrial sector

ACCEPTED MANUSCRIPT

Table 3 Life Cycle Inventory – ISTS (cont’d) Life Cycle Stage

Input

Life Cycle Stages A5 ISTS Assembly Life Cycle Stages A6 ISTS Transportation

FU1

Value FU2 FU3

FU4

80

246

809

Energy [MJ] Distance to Athens [km]

Energy [MJ]

FU1 13503

Oil (Athens) [MJ] Oil (Barceona) [MJ] Oil (Milan) [MJ] Oil (Frankfurt aM) [MJ] Oil (Copenhagen)[MJ] Oil (Oslo) [MJ]

35614 38586 66905 84817 88317 98458 0,00

Energy [MJ]

FU3 101629

FU4 135321

101177 129434 210509 249391 260568 290962

252746 276000 486876 619194 647126 722318

340077 371316 653637 825891 862530 963697

0,01

0,02

0,03

M AN U

Life Cycle Stages B2 ISTS Maintenance

FU2 40667

SC

Life Cycle Stages A7

RI PT

999 2908 2618 6471 6806 6972

Distance to Barcelona [km] Distance to Milan [km] Distance to Frankfurt aM [km] Distance to Copenhagen [km] Distance to Oslo [km]

ISTS Installation Life Cycle Stages B1 Fossil Fuel Consumption

607

Life Cycle Stages

A4, A6 2,9E-03 8,5E-05 8,7E-06 5,0E-08 7,8E-11 3,5E-02 1,2E-05 1,4E-04 4,1E+03 7,5E-06 7,3E-07

EP

A1-A3, A5 3,3E+02 1,3E+00 1,1E-01 9,8E-02 6,4E-02 4,3E+03 6,2E+00 7,9E+02 3,8E+05 8,4E-02 2,9E+00

AC C

Environmental impact categories GWP AP EP ODP ADPE ADPF FAETP HTP MAETP POCP TETP

TE D

Table 4 Life Cycle Impact Assessment (LCIA) results per kWth of ISTS

A7 5,6E+01 5,3E-01 1,1E-02 1,7E-11 2,8E-06 5,4E+02 2,7E-01 9,4E+00 6,1E+03 2,5E-02 2,1E-01

34

B1 1,5E+03 3,8E+00 4,1E-01 1,8E-04 3,5E-05 2,1E+04 6,1E+00 5,3E+01 1,6E+04 3,6E-01 3,4E-01

Total B2 1,1E-05 1,0E-07 2,2E-09 0,0E+00 5,5E-13 1,0E-04 5,3E-08 1,8E-06 1,2E-03 4,9E-09 4,1E-08

1,9E+03 5,6E+00 5,3E-01 9,8E-02 6,4E-02 2,5E+04 1,3E+01 8,6E+02 4,0E+05 4,7E-01 3,4E+00

Environmental assessment of solar thermal systems for the industrial sector

ACCEPTED MANUSCRIPT

Table 5 Comparative Life Cycle Impact Assessment (LCIA) results for ISTS and Conventional Water Heating Systems in Athens (FU1)

AP EP ODP ADPE ADPF

ISTS CWHS ISTS CWHS ISTS CWHS ISTS CWHS ISTS CWHS ISTS CWHS ISTS CWHS ISTS CWHS ISTS CWHS ISTS CWHS ISTS CWHS

1,89E+03 7,07E+03 5,60E+00 1,77E+01 5,28E-01 1,94E+00 9,81E-07 8,35E-07 6,40E-02 1,63E-04 2,55E+04 9,72E+04 1,26E+01 2,89E+01 8,56E+02 2,89E+01 4,00E+05 7,78E+04 4,71E-01 1,70E+00 3,43E+00 1,62E+00

M AN U

FAETP

Total contribution

RI PT

GWP

Hot water system

SC

Environmental impact categories

HTP MAETP POCP

AC C

EP

TE D

TETP

35

ACCEPTED MANUSCRIPT

Environmental assessment of solar thermal systems for the industrial sector Table 6 Life Cycle Impact Assessment results

RI PT

per kWth of ISTS at diverse European locations

Location Athens

Barcelona

Milan

GWP

1,82E+03

1,88E+03

3,07E+03

AP

5,44E+00

4,44E+00

5,75E+00

EP

5,10E-01

4,97E-01

ODP

9,81E-03

1,12E-02

ADPE

6,54E-02

6,54E-02

ADPF

2,46E+04

2,58E+04

FAETP

1,24E+01

1,32E+01

HTP

8,54E+02

MAETP

Copenhagen

Oslo

3,75E+03

3,71E+03

4,07E+03

5,10E+00

1,16E+01

4,23E+00

6,31E-01

5,92E-01

2,19E+00

6,22E-01

1,08E-02

1,05E-02

9,86E-03

9,82E-03

6,54E-02

6,55E-02

6,54E-02

6,54E-02

4,23E+04

5,14E+04

5,15E+04

5,70E+04

1,71E+01

2,41E+01

7,89E+00

7,46E+00

8,48E+02

8,87E+02

8,99E+02

9,08E+02

8,89E+02

4,00E+05

3,98E+05

4,16E+05

4,29E+05

4,21E+05

3,99E+05

POCP

4,55E-01

3,94E-01

6,14E-01

5,54E-01

7,72E-01

3,85E-01

TETP

3,42E+00

3,12E+00

3,31E+00

3,29E+00

3,32E+00

3,31E+00

AC C

EP

TE D

SC

Frankfurt aM

M AN U

Environmental impact categories

36

Environmental assessment of solar thermal systems for the industrial sector

ACCEPTED MANUSCRIPT

Table 7 Life Cycle energy and carbon emissions savings per kWth of ISTS at diverse European locations

Athens Barcelona Milan Frankfurt aM Copenhagen Oslo

Non-renewable energy consumption [GJ] 27,21 28,59 46,30 56,14 56,06 61,87

Energy Savings [GJ] 75,32 72,39 55,63 44,04 40,07 34,49

Carbon Emissions [ton CO2] 1,74 1,80 2,94 3,62 3,64 3,97

Carbon Savings [ton CO2] 4,95 4,74 3,64 2,93 2,69 2,29

RI PT

Site

Number of installations 188 1235 1472 3343 132 181

AC C

EP

TE D

Country Greece Spain Italy Germany Denmark Norway

M AN U

SC

Table 4 Number of 700 kWth installations and saved carbon monetary value per percentage of ISTS penetration into considered energy mixes

37

Saved Carbon monetary value [M€] 46,74 306,91 365,93 831,02 32,82 45,09

Environmental assessment of solar thermal systems for the industrial sector

ACCEPTED MANUSCRIPT

Acknowledgements

RI PT

The authors would like to thank “Johnsun Heaters LTD”, which provided the necessary technical information and data to enable the implementation of this work.

SC

References

[1] Heß, S., & Oliva, A. (2010). Solar Process Heat Generation: Guide to Solar Thermal system Design for Selected Industrial Processes - Guide developed within

M AN U

the framework of the project “SO-PRO - Solar Process Heat”. Last accessed 17 May 2017. Available from: www.solar-process-heat.eu

[2] IRENA (International Renewable Energy Agency) (2014). REmap 2030: A Renewable Energy Roadmap, June 2014, Abu Dhabi. Last accessed 17 May 2017.

Available

from:

http://www.irena.org/remap/IRENA_REmap_Report_June_2014.pdf

TE D

[3] European Solar Thermal Industry Federation (ESTIF) (2015). Solar Thermal Markets in Europe Trends and Market Statistics 2014. Last accessed 17 May 2017. Available from: http://www.estif.org/home/ [4] Karagiorgas, M., Botzios, A., & Tsoutsos, T. (2001). Industrial solar thermal

EP

applications in Greece: economic evaluation, quality requirements and case studies. Renewable and Sustainable Energy Reviews, 5(2), 157-173. [5] Kalogirou, S. A. (2002). Parabolic trough collectors for industrial process heat in

AC C

Cyprus. Energy, 27(9), 813-830.

[6] Muneer, T., Maubleu, S., & Asif, M. (2006). Prospects of solar water heating for textile industry in Pakistan. Renewable and Sustainable Energy Reviews, 10(1), 123.

[7] Schnitzer, H., Brunner, C., & Gwehenberger, G. (2007). Minimizing greenhouse gas emissions through the application of solar thermal energy in industrial processes. Journal of Cleaner Production, 15(13), 1271-1286.

38

Environmental assessment of solar thermal systems for the industrial sector

ACCEPTED MANUSCRIPT

[8] Kalogirou, S. A., & Tripanagnostopoulos, Y. (2007). Industrial application of PV/T solar energy systems. Applied Thermal Engineering, 27(8), 1259-1270.

RI PT

[9] Kalogirou, S. A. (2003). The potential of solar industrial process heat applications. Applied Energy, 76(4), 337-361. [10]

Kalogirou, S. A. (2004). Solar thermal collectors and applications. Progress in

energy and combustion science, 30(3), 231-295. [11]

Kulkarni, G. N., Kedare, S. B., & Bandyopadhyay, S. (2007). Determination of

SC

design space and optimization of solar water heating systems. Solar Energy, 81(8), 958-968.

Kulkarni, G. N., Kedare, S. B., & Bandyopadhyay, S. (2008). Design of solar

M AN U

[12]

thermal systems utilizing pressurized hot water storage for industrial applications. Solar Energy, 82(8), 686-699. [13]

Zambrana-Vasquez, D., Aranda-Usón, A., Zabalza-Bribián, I., Janez, A., Llera-

Sastresa, E., Hernandez, P., & Arrizabalaga, E. (2015). Environmental assessment of domestic solar hot water systems: a case study in residential and

[14]

TE D

hotel buildings. Journal of Cleaner Production, 88, 29-42.

Hang, Y., Qu, M., & Zhao, F. (2012). Economic and environmental life cycle

analysis of solar hot water systems in the United States. Energy and Buildings, 45, 181-188. [15]

Carlsson, B., Persson, H., Meir, M., & Rekstad, J. (2014). A total cost

EP

perspective on use of polymeric materials in solar collectors–Importance of environmental performance on suitability. Applied Energy, 125, 10-20. Greening, B., & Azapagic, A. (2014). Domestic solar thermal water heating: A

AC C

[16]

sustainable option for the UK?. Renewable Energy, 63, 23-36.

[17]

De Laborderie, A., Puech, C., Adra, N., Blanc, I., Beloin-Saint-Pierre, D., Padey,

P., ... & Jacquin, P. (2011, May). Environmental impacts of solar thermal systems with life cycle assessment. In World Renewable Energy Congress-Sweden (Vol. 57, No. 14, pp. 3678-3685). Linköping University Electronic Press, Linköpings universitet.

39

Environmental assessment of solar thermal systems for the industrial sector

ACCEPTED MANUSCRIPT

[18]

Otanicar, T. P., & Golden, J. S. (2009). Comparative environmental and

economic analysis of conventional and nanofluid solar hot water technologies.

[19]

RI PT

Environmental science & technology, 43(15), 6082-6087. Lamnatou, C., Notton, G., Chemisana, D., & Cristofari, C. (2014). Life cycle

analysis of a building-integrated solar thermal collector, based on embodied energy and embodied carbon methodologies. Energy and Buildings, 84, 378-387. [20]

Lamnatou, C., Notton, G., Chemisana, D., & Cristofari, C. (2015). The

SC

environmental performance of a building-integrated solar thermal collector, based on multiple approaches and life-cycle impact assessment methodologies. Building

[21]

M AN U

and Environment, 87, 45-58.

Comodi, G., Bevilacqua, M., Caresana, F., Pelagalli, L., Venella, P., &

Paciarotti, C. (2014). LCA analysis of renewable domestic hot water systems with unglazed and glazed solar thermal panels. Energy Procedia, 61, 234-237. [22]

Carnevale, E., Lombardi, L., & Zanchi, L. (2014). Life Cycle Assessment of

solar energy systems: Comparison of photovoltaic and water thermal heater at

[23]

TE D

domestic scale. Energy, 77, 434-446.

Martinopoulos, G., Tsilingiridis, G., & Kyriakis, N. (2013). Identification of the

environmental impact from the use of different materials in domestic solar hot water systems. Applied energy, 102, 545-555. [24]

Koroneos, C., J., & Tsarouhis, M. (2012). Exergy analysis and life cycle

EP

assessment of solar heating and cooling systems in the building environment. Journal of Cleaner Production, 32, 52-60. Koroneos, C. J., & Nanaki, E. A. (2012). Life cycle environmental impact

AC C

[25]

assessment of a solar water heater. Journal of Cleaner Production, 37, 154-161.

[26]

Directive 2009/28/EC of the European Parliament and of the Council of 23 April

2009 on the promotion of the use of energy from renewable sources and amending

and subsequently repealing Directives 2001/77/EC and 2003/30/EC

40

Environmental assessment of solar thermal systems for the industrial sector

ACCEPTED MANUSCRIPT

[27]

Kylili, A., & Fokaides, P. A. (2015). Competitive auction mechanisms for the

promotion renewable energy technologies: The case of the 50MW photovoltaics

[28]

RI PT

projects in Cyprus. Renewable and Sustainable Energy Reviews, 42, 226-233. Pyrgou, A., Kylili, A., & Fokaides, P. A. (2016). The future of the Feed-in Tariff

(FiT) scheme in Europe: The case of photovoltaics. Energy Policy, 95, 94-102. [29]

Directive 2003/87/EC of the European Parliament and of the Council of 13

October 2003 establishing a scheme for greenhouse gas emission allowance

[30]

SC

trading within the Community and amending Council Directive 96/61/EC

Directive 2009/29/EC of the European Parliament and of the Council of 23 April

M AN U

2009 amending Directive 2003/87/EC so as to improve and extend the greenhouse gas emission allowance trading scheme of the Community [31]

ISO (International Organization for Standardization). (2006). ISO 14040:2006.

Environmental Management- Life Cycle Assessment- Principles and Framework. [32]

ISO (International Organization for Standardization). (2006). ISO 14044:2006.

Environmental

Management-

Cycle

Assessment-

Requirements

and

TE D

guidelines.

Life

[33] Thinkstep GaBi. (2017). GaBi's website. Available from: http://www.gabisoftware.com/international/index/ [34] IEA (International Energy Agency) Solar Heating & Cooling Programme (2016). Solar Heat Worldwide Markets and Contribution to the Energy Supply 2014. Last

EP

accessed 17 May 2017. Available from: www.iea-shc.org/ Johnsun Heaters Ltd. Personal Communication. December 2016.

[36]

Kylili, A., & Fokaides, P. A. (2014). Investigation of building integrated

AC C

[35]

photovoltaics potential in achieving the zero energy building target. Indoor and Built Environment, 23(1), 92-106.

[37]

Valentin software (2017). T*SOL Dynamic thermal Simulation Program for

Designing and Optimizing Solar Thermal Systems. Last accessed 17 May 2017. Available from: www.valentin-software.com/en

41

Environmental assessment of solar thermal systems for the industrial sector

ACCEPTED MANUSCRIPT

[38]

Investing.com, Carbon Emissions Futures Historical Data Last accessed 17

May

2017.

Available

from:

https://www.investing.com/commodities/carbon-

[39]

RI PT

emissions-historical-data Kalogirou, S. A. (2013). Solar energy engineering: processes and systems.

Academic Press. [40]

Fokaides, P. A., & Kylili, A. (2014). Towards grid parity in insular energy

systems: The case of photovoltaics (PV) in Cyprus. Energy Policy, 65, 223-228.

International Energy Agency (IEA) World Energy Balance (2017). Last

SC

[41]

accessed 17 May 2017. Available from: http://www.iea.org/sankey/ SHIP (Solar Heat for Industrial Processes) Plants (2017). Database for

M AN U

[42]

applications of solar heat integration in industrial processes. Last accessed 17 May

AC C

EP

TE D

2017. Available from: http://ship-plants.info/

42

ACCEPTED MANUSCRIPT

Research Highlights Environmental impact assessment of industrial solar thermal systems (ISTS)




LCIA results relate linearly to the nominal thermal power of the ISTSs




Carbon savings range from 35 – 75 GJ and 2 – 5 tonnes of CO2 per kWth of ISTS




Life Cycle Produced to Consumed Energy Ratio: 0.015 (37° lat.) ― 0.006 (60° lat.)




Transportation environmental impact of ISTS within Europe is negligible

AC C

EP

TE D

M AN U

SC

RI PT