Designing the built environment that considers its climatic impacts is one of the challenges in modern times. Man-made activities, built environments, and technological advancements have led to serious environmental degradation, which poses significant risks to societal well-being and the environment. Exploring the effects of modern construction materials, design methodologies, and tropical design presents an opportunity to assess and understand their impact on a climatic scale, particularly in tropical countries. Environmental challenges can be addressed by understanding the effects of building design, creating climate-sensitive solutions, and optimizing current technologies to achieve unprecedented building performance.

This study examines a design approach intended to meet user comfort requirements while considering the impact of the current climate crisis and achieving overall sustainable design development. It thoroughly assesses the latest design approaches as an attempt to improve the current state of Naga City, specifically in the Central Business District 2 - Bus Terminal. The goal is to strengthen the city’s tourism, culture, and livelihood of its inhabitants residing in the area, taking into account the present fragile environmental conditions. The findings of this study may have implications for the local planning office to adopt design solutions and methodologies that are climatically suitable and contextually appropriate.

Keywords: sustainability, climatic impact, tropical design, climate change

This study explores the feasibility of a fully air-conditioned and solar-powered gymnasium at the University of Nueva Caceres as a sustainable response to the increasing energy demands and climatic challenges in Naga City, Philippines. It aims to design and simulate an energy model that integrates a photovoltaic (PV) system with the m. Using ASHRAE methods, the total cooling load was calculated to be approximately 199,862.38 watts (57 tons of refrigeration). Meanwhile, RETScreen software was employed to simulate the total energy generated and the financial viability of a 500 kW solar PV system. The system is projected to produce 712,935 kWh annually, accounting for 45.77% of the university’s energy consumption and saving approximately PHP 3.4 million per year. Despite high initial costs, the proposed system offers a payback period of 5.9 years and significantly reduces greenhouse gas emissions. The results suggest that implementing such a system is both economically and environmentally viable, enhancing user comfort while contributing to the university’s sustainability goals.

Keywords: photovoltaic systems, feasibility study, sustainability goals

With limited fossil fuel reserves, the Philippines has been exploring renewable energy sources, and one of the most promising options is hydropower. This research focused on the design and potential of a Hydropower Vortex Turbine (HVT) as an energy source, specifically tested in the Carolina Sitio Yabu River, Naga City. The study addressed the challenges posed by traditional hydropower methods, particularly in low-headwater river scenarios. Conducted at Carolina Sitio Yabu River with a 48 cm drop in water head, the testing involved power output measurements based on adjustments to turbine height (25.5 cm) and gate opening height (100%), revealing this configuration as the most favorable. Furthermore, the study revealed a need for a stronger correlation between flow rate and RPM within the specified range of tested flow rates. The calculated energy conversion efficiency for hydraulic and electrical power yielded a significant result of 41.82%. These findings bear substantial implications, suggesting the potential of HVT in low-water head river settings, contributing valuable insights for future renewable energy projects under similar conditions.

Keywords: Renewable energy, Hydropower Vortex Turbine, Low-waterhead River

This research study is subjected to experimental quantitative methodology on repurposing waste heat of split-type air-conditioners in response to the escalating global demand for efficient and sustainable energy solutions. The study aims to establish the correlation between the device's output temperature, the number of occupants inside, and the water flow rate. The study evaluates the practicality of implementing an Innovative Water Heater (INWAH) by examining heating capacity. The study aimed to explore the impact of various factors on the efficiency of this process, including (a) the population density within the area using the air conditioner, (b) ambient temperature, and (c) water flow rate. Furthermore, the research aims to determine whether the Innovative Water Heater (INWAH) device consistently achieves the desired bathing temperature by comprehensively reviewing its design, manufacturing process, and testing phases. We assess the device's effectiveness and impact on water temperature. The researchers used the equation Multiple Regression Analysis to compute the given variables and study the data. During the three-day (morning, afternoon, and evening) testing period of the device, it can successfully heat water using the heat produced by the condenser of a split-type air conditioning system.

Sawdust briquettes, derived from the collection of waste wood particles, offer a solution to address the increased price of LPGs in the Philippines. The study examines the machine's production process to increase the rate of briquette production. Additionally, it emphasizes the key factors that influence briquette quality, including the drying and burning times of briquettes, as well as their density and burning characteristics. Based on the five trials for the machine's production time, the average production time was 403.83 seconds, or approximately 6 minutes and 43 seconds. Also, the researchers assessed the quality of the briquettes produced by the machine. The briquettes underwent experimentation to test the hypothesis that the longer the briquette has been dried, the shorter the burning time. The results were analyzed using correlational analysis. The result showed that the drying time and burning have a very high negative correlation, with a correlation coefficient of ρ = -0.962, indicating an inverse relationship. Additionally, the briquettes were experimented with to determine whether their density could increase the burning time. The results were also analyzed using correlational analysis. The findings indicated a noteworthy positive correlation between density and burning time. The results showed a robust positive relationship between density and burning time, with a correlation coefficient of ρ = 0.951. The results indicated that the proposed design and quality of the sawdust briquettes reduce production time and extend the burning duration of the briquettes.

A community multiplex green interactive space plays a vital role in our daily social lives, aiming to bring individuals together in a coherent setting that is open to the public and versatile enough to cope with climate change. This community space includes specific areas designed to accommodate the needs of personnel, guests, and especially the public. The project offers amenities that distinguish it from others by balancing industry and the environment while remaining functional, cost-effective, and accessible. Additionally, a biomorphic approach was employed as a design principle to consider ecological factors alongside "green architecture." This study emphasizes the environment, particularly climate, based on the premise that nature is essential (Aulia F. and Ishomuddin M., 2016). Consequently, work-life balance emerges naturally in well-planned community interactive spaces due to various factors such as comprehensive amenities, convenience, accessibility, and proximity to leisure and retail.

Specific design solutions have been integrated into the project, including sun control and shading devices, landscaping and vegetation as noise and thermal buffers, as well as evaporative cooling surfaces. These elements are crucial for creating a space where the public can work efficiently while also enjoying leisure time, all while considering physical and psychological comfort.

Keywords: community engagement; green architecture; biomorphic architecture; employment opportunities

Technology enables sustainable water management by developing an Arduino-based smart water meter, providing real-time online access to water consumption. Integrating Arduino Mega and ESP32 ensures accurate water readings through water flow sensors and facilitates data transfer to an online platform. The challenge in designing an Arduino-based smart water meter system is to ensure accuracy and provide real-time online access for consumers and the Metropolitan Naga Water District. Another aspect of the device is that it enables the reading of the actual volume flow rate, detects leaks, and reduces non-revenue water for the Metropolitan Naga Water District. This study developed a prototype to help the Metropolitan Naga Water District become more productive in water reading, reduce workforce, ensure customer satisfaction, minimize non-revenue or unbilled water, and manage water distribution more effectively on a monthly basis. The researcher's findings suggest that the proposed device exhibits an impressive accuracy rate of 99.5% when measuring flow rate and volume, whether connected physically or accessed online. The significance of these results lies in their implications for the device's performance once it is implemented. In other words, the study highlights the device's effectiveness in practical scenarios, showcasing its reliability and precision in capturing and quantifying flow rate and volume data under various conditions, whether physically connected or accessed remotely through an online interface. This level of accuracy underscores the device's potential to deliver reliable and consistent measurements,

enhancing its utility and effectiveness in real-

world applications.

This paper presents an approach to monitoring the water quality of Lake Buhi, a vital aquaculture area in the Bicol Region, which serves as the primary water source for hydroelectric power and irrigation in the Rinconada Towns. The prototype developed for this study incorporates a 3D-printed hollow half-sphere buoyant housing for electronic components, a battery, and a solar panel. It aims to acquire accurate real-time data on water quality parameters: temperature, pH, dissolved oxygen, and turbidity. These parameters are monitored using sensors that employ UART digital and analog protocols, all under the control of an Arduino Mega 2560 microcontroller. Data collected are recorded and stored on a micro-SD card, generating comprehensive graphs and tables.

In assessing the prototype's precision and accuracy, all results were compared with data obtained from conventional analog water quality testers at the BFAR Region V laboratory. The research findings demonstrate the prototype's remarkable accuracy, resulting in impressive precision rates for the measured parameters: temperature (99.60%), pH (99.04%), dissolved oxygen (99.623%), and turbidity (91.57%). The paired t-test determined that all computed t-values for the four parameters fell below the critical t-value of 2.26, affirming the device's precision and reliability. The prototype exhibited exceptional precision, delivering consistent measurements within margins of uncertainty of ±0.236°C, ±0.009, ±0.045 mg/L, and ±0.269 NTU for temperature, pH, dissolved oxygen, and turbidity, respectively. These values signify the acceptable margins of uncertainty for each parameter.

Keywords: temperature, pH, dissolved oxygen, turbidity