1. Central Luzon State University, Science City of Monuz, Nueva Ecija, Philippines.
2. Saint Louis University, Baguio City, Benguet, Philippines.
3. SISIDS Strategies Philippines.

*             Correspondence: britprinx@gmail.com

Keywords: plastic-bottled water, solar-powered filtration, cooling water facility, Munoz

1. INTRODUCTION

Water as a compound is very important for a thriving ecosystem, and accessibility to potable drinking water has been a critical agenda of most international and national policies including those of the United Nations [1] of which one of its essential millennial objectives is to provide or support physical infrastructure initiatives and institutional and regulatory policies for adequate and clean water access. The estimated 2.5 liters or approximately more than eight cups per adult be the advisable daily intake recommended by [2], and a similar figure is given as eight 8-ounce glasses or 2 liters, i.e. 8×8 rule from experts on water intake for its significant health’s benefits [3]. It is believed that such an amount of water intake would provide and support healthy living for humans to unlock a higher degree of healthy, social, economic growth and productivity in the long run. Safe and clean drinking water became the UN Sustainable Development Goal target 6.1, and in line with this target, it is necessary that portable water remain assessable to many people; placing water as a universal basic human right and facilitating such via cleaner production practices and engineering a renewable solution towards the provision of portable drinking water to achieve a higher human development goal would be undertaken in this study.  This study would attempt to utilize a multidisciplinary approach through social engagement, data collection through survey, and descriptive statistical analysis towards achieving a human health-related and environmental sustainability goal to address the above issue through systematic focus group discussion among the students in Central Luzon State University Science City of Munoz led by the researcher and upon which the design of the questionnaire used for the survey targeting the university community on its water intake information and plastic bottled water consumption and by using descriptive statistics as decision support tool toward developing a system for plastic waste reduction and solar energy-based micro-water system. We hypothesized that this would stimulate adequate water intake for its health and environmental benefits. Sadly, drinking water remained undersupplied in most parts of developing countries and access to it is either constrained by availability, distance, cost and quality yet a simple measure such as a cleaner production strategy could be implemented to improve clean water supply at the sources [4-7]. For the most part, the current drive towards adequate drinking water is now beginning to contribute to excessive plastic bottle waste on one end, and not drinking enough is a leading cause of many death [8,9], and from its 2019 updated estimations, 90% of the global population (6.8 billion people) uses at least basic water services of which majority of them need improvement and as stated by the organization, “785 million people lack even a basic drinking-water service, including 144 million people who are dependent on surface water” resulting to 2.2 billion people lacking access to safe and clean drinking water and to add to this, it elaborated that “contaminated water can transmit diseases such diarrhea, cholera, dysentery, typhoid, and polio; of which the last is increasingly resurfacing in the Philippines after many years of health efforts and programs. To address this challenge on the individual level, many have resorted to buying bottled water over the years and this has increasingly become another source of pollution; adding to the larger amount of plastic in the environment. The increasing use of plastic water bottles all over the world today is attracting a lot of research interest, and since 1986 the ocean clean-up data from the Center for Marine Conservation estimated that plastic bottles, pieces, lids and caps are one of the “dirty dozen”; hence, the twelve items most found frequently in the ocean. The effort to cut down the plastic polluting agents in the ocean seems daunting, leading to devastating effects on marine lives [10,11], and more of these negative effects on land are being reported as plastic waste occupies sanitary landfills [12], and can be seen creating litters in many third world countries. Plastics are non-biodegradable and their micro composites bioaccumulate through the food chain to higher species when they are burnt as waste; they pollute the air causing respiratory system, and physiological and genetic damages [13]. The excessive plastic waste is currently being generated annually-380 MT with water bottles from portable drinking water and plastic packaging items accounting for the majority of the waste stream and with an estimated 8.8 million metric tons (MT) of plastic and micro-plastic materials entering the ocean from coastal communities each year [14], such figure would probably increase if more plastic water bottle and the other packaging plastics are still being used. Unfortunately, the Philippines is now rated as the third-worst plastic polluter in the ocean by Greenpeace and according to a report by Ocean Conservancy in 2017 “China, Indonesia, Philippines, Thailand, and Vietnam dump more plastic in the sea than all other countries combined”. It is noteworthy that the effort by the “Global Alliance to End Plastic Waste” (AEPW) which comprises 30 member companies with a budget of 1.5 billion US Dollars over the next five years from 2019 to invest in innovative technology for recycling, sustainable partnership with a sound business model for circular economy and science-based global information sharing with scalable solutions to minimize waste through these agenda and targets is currently underway and are mostly end of the pipe initiatives, therefore, much is yet to be done on the waste sources which are principally controllable if identified and proper measures taken to reduce the waste from these ends.  Moreover, budgeting for such efforts has been recently hampered globally due to the Covid-19 pandemic that has dwindled many plastic pollution cleaning efforts by the government. Hence, targeting the source of plastic pollution while increasing the opportunity for more water intake would arguably consider a more sustainable solution. The university community represents an important setting for human development and transformation to meet the skill sets and knowledge demands of the 21st Century and as such, the human elements of the university ecosystem across the world are deemed important, for it is within this element that interaction through learning, teaching, researches and innovation take place. Therefore, conduciveness and the overall health balance from adequate water supply for drinking and also for sanitation are critical to the survival of scholars to meet the challenges of the world today within and outside the university environment. Adequate water intake has been linked to proper learning and mental condition for both students and teachers alike including positive effects of hydration on students’ attention and other related cognitive physiological functions Pop, [15-17] established the positive mood and proper sleep pattern in connection with adequate water intake, while [18] reviewed water intake related researches and concluded that constant hydration is an optimum requirement for achieving balance well-being. Unfortunately, many universities in third world countries either lack quality water supply or potable water for drinking from the university facility [19], so most affected students are now relying on bottled water purchases and this has significantly affected their budget for daily basis as they are mostly from low-income parents. Studies have also shown that students would opt for soft drinks over a bottle of water due to the better taste of the former and as such do not take enough water daily as needed by their body.  In essence, the CP principle being well articulated among sustainability experts has to be practicalized in universities and also be used as a basis during project implementation and evaluation [20]. Universities offer a plethora of options and opportunities where the CP initiative can be seen and copied into communities around it and in this study, Central Luzon State University was chosen as a strategic community to leverage the outcome of water engineering research toward its sustainability as its current water supply for drinking is unfit to be considered portable as evident in the work of [21] who conducted a test on the water from the different colleges and the results yield presence of Escherichia coli (E.coli) after a 24-hour incubation on the different plates investigated. In terms of conceptualization of engineering solutions to address water challenges in communities, an interesting effort  [22] through assessing the performance and life cycle analysis of potable water production from decentralized rainwater sources as compared to centralized ones was made and their study indicated that although portable water from point of use on a large scale assessment performed poorly due to the high cost of energy input, however, through the use of alternative energy sources, the benefits of such system outweigh the centralized ones significantly due to its potential of creating more point of use across space and time and this underscores the necessity of such design in third world country and communities therein where portable water access is a big challenge to many and where the centralized system has failed so the use of plastic bottled water becomes prevalence; constituting to the large heap of the waste stream that eventually lands on the ocean. Using a similar approach to rainwater harvesting technology through a decentralized system as compared to the municipal water system, [23,24] in the United States, and [25] in the Mediterranean regions found that decentralized water system is more suitable for those locations except for few environmental risk which could be resolve with proper design, however, location and distribution strategy that this system offers over the central system were the most important variables that enable a huge advantage of harnessing water supply from microsystem. This study utilizes the current quality of the public water supply on the campus and then assesses the reasons through distributed survey questionnaire to students’ and non-student’s preferences or choices on what they drink daily, the amount of water intake as a comparative to the recommended or optimum amount set by the WHO. We systematically utilize descriptive statistics charts insights and finally conceptualize a design for a potential micro-water dispensing solution for sustainable portable water supply on the campus. More unlike the AEPW ambitious goals that never mentioned plastic waste reduction strategy and the pollution prevention (2P) or cleaner engineering solution that targets consumer behavioral changes, this study would propose an innovative solution to curb the use of plastic water bottle using Central Luzon State University as a case in point and thereby, strategically locate the greener and safer system on the students’ preferred area(s) of installation and the using the design to meet the university water consumption goal through encouraging more water intake daily as a result of its cheaper cost and huge environmental, social and health benefits.  This study aims to answer these three questions which capture the entire scope of the research; Are CLSU students and staff drinking the right amount and quality of water? Are they adding up to the excessive plastic water bottle being reported as a source of pollution to the environment? And are they willing to address the above two challenges through the acceptance and willingness to pay for the installation of the conceptualized solar-powered water disinfection and cooling device? It is believed that with these three essential questions, our research would be able to implement its principal objectives which are deeply connected to source reduction of plastic waste and then the innovative and green engineering solution to support the resilience and sustainability of the university community on its health goals toward achieving adequate water intake by the entire stakeholders. The significance of this study is to operationalize the idea of green consumption alongside a cleaner production concept within the university as recommended [26] in which case they contend that greener consumption patterns in their myriad forms have the capacity of gravitating consumers to other forms of environmental lifestyles. Hence, throughout this study, we would like to achieve these four sets of objectives; To assess the average amount of water intake of students and non-students in CLSU, to know if there are opportunities and available preferences for water intake for students and non-students in CLSU, to conceptualize a greener and safer alternative water intake opportunity through solar powered-micro water disinfection and dispensing station that will effectively increase students’ and non-students’ water intake in CLSU and also reduce the use of plastic water bottles that has been linked to a host of environmental degradation and to assess if the students are willing to be involved in the shouldering the cost and the management associated with such a facility on the campus.

2. MATERIALS AND METHODS

A focus group discussion was utilized to harness the most likely questions that would inspire the best and most relevant answers needed for the study. It was then followed by the distribution of questionnaires and through random sampling by six students to cover nearly all the colleges on the campus. The entrances of the colleges were used to interview both students and non-students for three consecutive working and class days. To ensure reasonable accuracy of results from the used sample number derived from the total population in the university. A total of N=304 sample size was used from the estimated 13,488 population size of the university community. Hence, Slovin’s Formula defines and provides a valid claim on reasonable sample size (n) for accuracy from a known population size (​N​) and the acceptable error value (​e​). Through the formula n​= N​ ÷ (1 + ​Ne​2); n = 272 which is far less than the survey sample 304. Hence, with a 0.06 acceptable error value or margin of error or 94% confidence level, it can be safe to say this research sample size is a truly representative sample of the university population (records for students’ enrollment: 12,535, Faculty: 475, and Staff: 478). The conceptual layout plan and engineering design were inspired by research on filtration and disinfection techniques and the power supply is to be a renewable energy source; solar which is readily available on the campus all year round. The design can be seen in figures, all have different filtration media as alternative solutions which are readily available in the country.

3. RESULT & DISCUSSION

The data presented herein represent the consumption and the perception of the 304 CLSU students and non-students about safe drinking water and the possibility of installing a solar-powered water filtration system. Interestingly, the survey results indicate that portable water is a vital resource on the campus and shouldn’t be ignored by the management. Of the 304 students, the majority are aged 19 years old (37%) and mostly female (56%). All the respondents drink water wherein a majority uses a 1L capacity plastic bottle. Based on the frequency of drinking water, 33% said that they drink 2-3 times in day followed by 32% of the respondents who stated that they drink water whenever the need arises. Notably, even though all the respondents drink water, 26% feel like they don’t want to drink water and the most stated reason (57%) is the availability of alternatives such as soda (58%), and hot beverages (19%) and others. It can be noted that most of the respondents (29%) prefer to drink cold water over warm water (5%) which can be attributed to the humid weather at the University. Additionally, the respondents prefer to drink water that is in plastic bottles (23%) and if the university provides a clean supply of water (23%).

Figure 01: The pie chart of question 2; Where Do You Mostly Drink Water

When asked about the number of water bottles accumulated on the campus, 52% answered that they are aware of it. To help reduce the number of water bottles being accumulated daily, most of the respondents stated that they will bring their tumblers to buy water (47%) followed by 34% of them offering to promote the use of recycled bottles. Most students surveyed have their water intake from plastic bottles 39%, (See figure 02), while 22% drink from the canteen which is mostly serviced by the unfit for drinking university water supply and the 33% drink only at their boarding homes of which a fraction of this group lives on campus hence, drinks only from the university supply which isn’t safe due to the presence of E. coli as earlier identified.

Figure 02: The line plot of question 2; Where Do You Mostly Drink Water

It can be noted that most of the respondent’s drink from the campus facilities (60%). A majority of them (43%) describe a safe drinking water facility as a place which is safe to drink water from whereas 25% describe it as a facility that uses green energy for water supply. Soda and hot beverages are most preferred with 58% responding since they considered them safer to drink and enjoyable.  Awareness of environmental concern on the daily number of bottles accumulated on campus is almost equally divided into 50%, which means that they are environmentally conscious of the wastes accumulated on the campus but unable to translate the awareness into not buying water from plastic bottles or drinking the prescribed amount of water by the WHO. Respondents say that 60% drink water from the campus facility and they said that they can help reduce the accumulation of water bottles by bringing with them tumblers. When they were asked if they will drink more water if the school will provide a better facility for drinking water, 68% positively said they would while 25% were not sure if their daily water intake will increase. On a positive note, 78% of the respondents are willing to pay the money they spent on water per semester on a solar-powered filtration, disinfection and cooling water facility. This suggests the potential user adoption of such a facility if it is conceptualized and made available. Accordingly, about half of the respondents prefer that the water facility be installed in the university canteen. The university canteen is strategically located in the middle of many colleges and dormitories which could be the reason for the preference. However, many also preferred for such facilities to be installed in rooms or colleges). To validate the data generated insight from the most vital question leading to a conclusive finding on the most preferred means of water intake in the university, an analysis of variance was implemented to figure out if there is no significant difference between the number of the respondent from the different departments in the colleges and their stated preferences, and surprisingly, the probability value indicates the acceptance of the null.  Solar-powered water dispensing system would offer a reliable source of electricity to power both the UV lamps and the cooling unit inside the dispensing tank. Solar power is cheap, sustainable and greener than the current power sources in the university and would be readily available to supply the electricity needs to power the system during the day when students are in most need of water as they are within the university compound. The use of zeolite 14-40 mesh and the granular which are considered microporous hydrated aluminosilicates have been documented by many researchers [27-29]. Natural zeolites provide high cations and anions exchange functionalities and are readily available, safe and cheap. The sheer amount of surface area to volume ratio offers the crystalline zeolite their water filtration and purification advantages as they readily remove impurities, ammonium and heavy metals such as As, Zn, Cr, Pb, Cd, Cu, Mn, Fe, Mg etc., at relatively low concentrations and preserve water chemistry [30-32]. UV ray disinfectant is preferred due to its environmental friendliness, low cost, safe, low energy requirement in order of few tens of watts, the ability to deliver and has no residual chemical disinfectant. To maintain the UV transmission care must be taken to periodically clean the underwater lamp sleeves to get rid of the deposits while a UV sensor should be used to monitor the magnitude and dosage of UV delivery and efficiency.

Figure 03: The Conceptualized Design for Safe Drinking Water Natural Zeolite filter-based model that uses solar energy to power the UV-ray for microbial disinfection and to supply needed voltage for the cooling unit inside the storage tank.

The university is located in central Luzon province of Nueva Ecija that shares the same solar or sun irradiation hour as the manila May averaging 280C according to the Philippine Atmospheric, Geophysical and Astronomical Services Administration (PAGASA) with the highest average monthly sun hour or a sunshine hour between April to May being 250 hours. These advantages are due to the geographic location of the country (near the equator) and the climatic condition that allows more irradiation hours per day. Interesting, at every kWh or solar energy generated from a solar-powered system, 0.88 kilograms of climate forcing carbon dioxide are eliminated from the ecosystem, however, with just about 0.08-0.2lbs CO2 per kWh which is far less than those from natural gas and coal when compared in terms of carbon equivalent through life-cycle emission rates [33].  The solar energy harvest has been reported with a peak of over Olongapo and its neighboring municipalities at 7kWh/m2/day [34], and using the formula deployed by the above author through the multiplication of the Latitude of Science City of Moniz by the country’s correction rate of Earth’s rotational axis quarterly tilting of 0.812117, one would obtain the Optimal Angle of Solar Panels (OASP) on a particular project in the country. For instance, by considering fixed-mounted solar panels as shown in Figures 3 and 4, the following can be considered the OASP to achieve maximum solar energy production to supply both the UV-Ray Tube and the cooling unit inside the dispensing tank.  0.812117 x latitude of Science City of Moniz = angle from horizontal facing south.  To be able to supply a daily output of 1,000 liters of water to be dispensed using the facility. The engineering Toolbox (2004) was used and here, a water-chiller refrigeration ton could be relied on for an optimized solar panel module needed and it is defined as; 1 Refrigeration Ton (RT) = 1 Tons Cond = 12000 British thermal unit (Btu)/h = 200 BTU/min = 3025.9 k Calories/h = 12661 kJ/h = 3.517 kW, 1 kW = 0.2843 Refrigeration Ton (RT), By definition, a ton is the amount of heat removed by an air conditioning system (that would inside the tank) that would melt 1 ton (2000 lbs.) of ice in 24 hours. The heat required to melt 1 lb. of ice at 32 0F to water is 144 Btu. Hence, the number of solar panels assuming each with the conventional/common 200Watts capacity needed to accommodate such cooling would be: 100w = 1kW; 3.517kW = 3517W; Therefore, 3517 / 200W; The number of panels would be 17.585; which is equivalent to 18 standard solar panel modules. An impressive development, comparison of performance and life-cycle assessment of a device known as POU with conventional water supply for drinking [35], the POU device was able to reduce levels of microbiological and pathogen parameters in delivered water to meet the UK, EU and WHO potable standards. The device attained a reduction to a potable standard of microbiological determinants, such as total viable counts and coliforms and full removal of pathogens including Pseudomonas aeruginosa and Legionella spp. using ozone technology. However, in their work, only energy efficiency was aimed at with less emphasis on the device being able to cater for the need of the people which also remained hard to be quantified. With my design, I hope multiple benefits could be generated by targeting improvement of the available water supply to the university community by making it portable for drinking while reducing the constant purchase of water from plastic bottles.

Figure 04: An alternative Conceptualized Design for portable Drinking Water uses an Activated Carbon-based filter powered by solar energy to supply the minimum voltage requirement for the UV-ray for microbial disinfection and to supply needed power input for the cooling unit inside the storage tank.

4. CONCLUSION

The shift to cleaner production and green supply strategy in water engineering is currently being explored and efforts to implement many of the projects aiming for sustainable clean and safe water supply have been challenged by the over-reliance on bottled water; which has become so ubiquitous in all communities of humans. Unlike previous research where plastic water bottles and their composites are identified as environmental pollutants without engineering a scalable and cleaner production solution to alternatively green-supply what they were produced to contain or packed, for instance- portable water, this study is designed to develop a solar-powered micro-water filtration and cooling system solution geared towards stimulating students and non-students to provide them with a potable water source and through incentivizing reuse of drinking water flask instead of a disposable plastic bottle, hence eliminating the need to use “one-time plastic water bottle” which is currently the norm. It is believed that by developing an engineering solution which targets communities with less water drinking habits and with a huge waste stream from the plastic water bottle, a sustainable clean water consumption with less or no plastic waste generation can be achieved on the campus with designed solar-powered water treatment, filtration, and cooling system. To summarize the findings generated from this survey, there is a high adoption potential for solar-powered disinfection and cooling portable water facility to be installed in CLSU’s university canteen. To decrease the accumulation of plastic bottles, encourage the CLSU residents and students to drink water as prescribed by the WHO, and provide safe drinking water for all, the installation of a water facility in a strategic and accessible location would be beneficial idea. Since a majority of the respondents showed positive feedback on using the money they spent on buying water in plastic bottles for the installation of a water facility, the money that would be generated could partly be used on this project. It is therefore very important to have a drinking facility inside the campus which is safe and environmentally friendly and the conceptualized solar-powered water filtration, disinfection and cooling system might be of a great healthy and environmental supportive facility in the university near the university canteen.

5. RECOMMENDATIONS

It is hereby recommended that the designed concept be further investigated and a possible feasibility study conducted on the cost-benefit analysis as well as the strength, weaknesses, opportunities and threats of installing such a facility within the university compound. This could be strategically formulated based on the data collected and further surveys are designed to capture more students and the other vital respondent to have a more representative of the population studied. It is also recommended that the Life-Cycle Assessment of the entire facility layout be conducted using relevant industrial ecological tools to compare such a green project with the current scenario of plastic water bottle usage and the host of externalities such behavior incurs to fully implement possible measures and to have data-rich decision support for the conceptualized solar-powered water filter, disinfectant and cooling system. Finally, a similar study should be undertaken in nearby universities and communities to collate data and harmonize them for modeling and project duplications across the province and the country; as this would technically support the sustainable development of the universities in the country.

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