Powering Progress : A Hospital’s Journey towards Renewable Energy

. A case study of implementing solar powered infrastructure with grid connectivity, exemplifying the integration of renewable energy solutions in healthcare facilities. The study examines the design, implementation, benefits, and challenges faced during the transformation of a conventional energy based hospital into a sustainable, eco-friendly institution. By leveraging solar photovoltaic (PV) technology and grid-tied systems, the hospital achieves significant energy and financial savings, reduced carbon emissions, and enhanced energy resilience. The findings from this case study provide valuable insights for healthcare institutions seeking to adopt sustainable practices and contribute to a greener future.


Background
In the healthcare industry, an uninterrupted and continuous power supply is an absolute necessity.Critical areas such as Intensive Care Units (ICUs) and Operation Theaters demand constant power to ensure the safety and well-being of patients.In the past, energy managers heavily relied on Diesel Generator sets and Uninterrupted Power Supply (UPS) systems to fulfill these energy requirements.However, the contemporary landscape offers a range of environment friendly energy sources.The question that arises is: how can this diverse energy be effectively managed to meet the demands of healthcare facilities?Moreover, can it provide a seamless power flow, considering that its consistency might be influenced by various factors such as irradiance, geographical elevation, and other natural variables?The answer to this multifaceted question is affirmative.By digging into a comprehensive understanding of how different energy sources function and conducting a thorough assessment of available resources, it becomes feasible to ensure a reliable energy supply.This intricate process is exemplified by the experience of Masai Medical Foundation's Shri Swami Samarth Hospital situated in Kolhapur.

Consumer Backgrounds
The hospital considered for this case study is Masai Medical Foundations' Shri Swami Samarth Hospital.It was established in 1995 at Lugdi lane, Somwar Peth, Kolhapur.Hospital is situated in the heart of Historical & Famous Kolhapur city in Maharashtra State.The hospital is well known for their pediatric services in Kolhapur.The hospital is built within the land having an area of 8000 sq.ft.It has a total built up area of around 40000 sq.ft. and the carpet area of terrace is around 6500 sq.ft.The MSCB installed system is rated for a total of 120kVA, with a total of 3 meters, each sanctioned 40kVA.The hospital has a substantial demand for energy as it has some high power consuming electrical machines for pumping systems, AHUs, NICUs, PICUs, ICUs, and for other utilities.Also, the hospital provides services such as 24 Hours OPD, Immunization Clinic, Asthma Clinic, Adolescent Clinic, many more, which requires an uninterrupted power supply for 24 Hours.(All these load demands are satisfied by using 3 solar PV systems of 40kW each.)

Challenges Faced by Consumer
• Elevated energy expenses: The high energy expenses are straining a hospital's budget, diverting financial resources away from patient care, medical equipment upgrades, and staff development.In an era of rising healthcare costs, managing energy expenses is crucial to maintaining financial stability.The hospital operates around the clock, which means they consume a substantial amount of energy for lighting, heating, cooling, and running medical equipment.Elevated energy costs are affecting the hospital's overall operational efficiency.Beyond financial implications, hospitals are also concerned about their environmental footprint.High energy consumption contributes to greenhouse gas emissions, and hospitals have sustainability goals and obligations to reduce their environmental impact.
• Dependency on DGs and grid supply for energy needs: DGs typically run on diesel fuel, which emits pollutants and greenhouse gasses when burned.Increased dependency on DGs can contribute to air pollution and have negative environmental consequences.Also, the operating and maintaining DGs is really very expensive, including the costs of fuel, maintenance, and compliance with emissions regulations.Hospitals must budget for these ongoing expenses.Dependence on DGs may pose challenges during extended power outages if a hospital's fuel supply becomes limited or inaccessible due to emergencies or supply chain issues.

Objective of this Study
The primary objectives of this case study are as follows: 2.1 Sustainable Transformation: The case study aims to explore the process of transforming a conventional energy-dependent hospital into a sustainable and environmentally friendly institution.This transformation is achieved through the adoption of solar photovoltaic (PV) technology and the integration of grid-tied systems.
2.2 Insights for Healthcare Institutions: Valuable insights and lessons learned from the case study is presented.These insights are intended to serve as a practical guide for other healthcare institutions seeking to embrace sustainable energy practices, addressing the unique energy needs and challenges faced by the healthcare sector.

Energy Cost Optimization:
The study delves into the strategies and policies that organizations can leverage to optimize their energy costs.Particular attention is given to the context of solar energy integration and net metering, which play pivotal roles in reducing operational expenses.
2.4 Real-World Application: Drawing from the real-world experience of Masai Medical Foundation's Shri Swami Samarth Hospital in Kolhapur, Maharashtra, the case study showcases a practical application of sustainable energy solutions.This practical example illustrates how these concepts can be effectively implemented in a healthcare setting.

Financial and Environmental Benefits:
The case study conducts a thorough analysis of the financial benefits stemming from sustainable energy integration.This includes assessing payback periods, return on investment (ROI), and the levelized cost of energy (LCoE).Furthermore, it underscores the positive environmental impact of these initiatives, emphasizing their contribution to broader decarbonization efforts.
The overarching objective of this case study is to offer a comprehensive and informative resource for healthcare institutions seeking to transition to sustainable energy solutions.It addresses the intricacies of this transformation while considering the unique demands and challenges that the healthcare sector faces.

Understanding terminologies:
• On-Grid System: An on-grid system, also known as a grid-tied system, is a renewable energy setup, often using solar panels, that is connected to the main electrical grid.It allows you to generate your electricity and feed excess power back into the grid, potentially earning credits or payments from your utility company.
• Net Metering: Net metering is a billing arrangement for solar or other renewable energy systems connected to the grid.It enables you to receive credits for excess electricity you generate and feed back to the grid.These credits can offset the electricity you draw from the grid when your system isn't producing enough power, effectively reducing your overall bill.
• Battery Bank: A battery bank is a collection of connected batteries used to store electrical energy.It's commonly used in off-grid systems or in conjunction with renewable energy sources to store excess energy generated during peak production periods for use when energy production is lower, such as during the night or on cloudy days.
• Control Panel: A control panel is a device or interface used to monitor and manage various systems or processes.In the context of energy systems, it might provide information about energy production, consumption, and storage.It can also allow for adjusting settings and configurations to optimize system performance.
• DG Sets (Diesel Generator Sets): Diesel generator sets, often abbreviated as DG sets, are backup power sources that use diesel engines to generate electricity.They're commonly employed when a stable power supply from the grid is unavailable or as a backup during power outages.DG sets are used in various settings, including hospitals, data centers, and remote areas.
• AHUs (Air Handling Units): An Air Handling Unit (AHU) is a device used to regulate and circulate air in heating, ventilation, and air conditioning (HVAC) systems.It plays a crucial role in maintaining indoor air quality, temperature, and humidity within buildings.AHUs are typically equipped with components such as filters, heating and cooling coils, fans, and dampers.They draw in outside air, condition it by either heating or cooling, and then distribute the conditioned air throughout the building.AHUs are essential in ensuring comfortable and healthy indoor environments in various settings, including residential, commercial, and industrial buildings.
• UPS: An Uninterruptible Power Supply (UPS) is an electrical device that provides emergency power to a load when the input power source, typically the mains power, fails.Its primary purpose is to provide a temporary power source during electrical outages, ensuring that critical systems and devices remain operational.UPS systems are commonly used in various settings, including data centers, hospitals, industrial facilities, and homes, where continuous power supply is crucial to prevent data loss, equipment damage, or service interruptions.
• Tariffs: Tariffs in the context of the energy sector usually refer to the rates, charges, and fees that are imposed by utilities or energy providers for the consumption of electricity, natural gas, or other utility services.Tariffs can vary based on factors such as the amount of energy used, the time of day when the energy is consumed (time-of-use tariffs), the type of consumer (residential, commercial, industrial), and the region.Tariffs help determine the cost structure for energy consumption and play a significant role in energy management and budgeting for individuals and businesses.
• TOD tariff: Under the ToD Tariff system, Tariffs during solar hours (duration of eight hours in a day as specified by the State Electricity Regulatory Commission) of the day shall be 10%-20% less than the normal tariff, while the tariff during peak hours will be 10 to 20 percent higher.
• Connected load: Connected load refers to the total power rating of all electrical devices and equipment connected to a power supply.It represents the maximum potential power consumption if all devices operate simultaneously at full capacity.Utilities use it for infrastructure planning, billing, and load management.It helps design electrical systems, optimize energy usage, and ensure stable operations.Connected load isn't the same as actual energy consumption, which can vary based on usage patterns and device efficiency.

How net metering works
Net metering is a billing system in which units are credited to the consumer's bank, against the energy they generated with help of solar photovoltaic power plants and fed to the grid [7].Net metering is introduced to encourage adoption of solar power plants.Installing a net metering system allows consumers to offset their electricity bills with the power they generate from solar panels.As mentioned in consumer background, consumer is from Maharashtra hence consumer need to sign net metering agreement with Maharashtra state electricity distribution company limited (MSEDCL).Under this agreement consumers have to install bidirectional meters, which will keep record of electricity generated and electricity consumed by consumers from the grid, and the consumer's account will be credited for excess energy exported to the grid.Cost of net metering is approx.30000 including all charges.Process for installing Solar net meter is followed in given way: Here are some additional information and precautions one should take: 1) Maximum capacity to be installed under net metering scheme is 1 MW 2) Extra fee is charged as application, inspection fee etc. 3) Property tax is imposed on the solar system.Precautions: 1) Solar system must be installed by register installer 2) Solar system must meet the technical standards of MSEDCL 3) Solar systems must be inspected by MSEDCL before commissioning.4) Equipment such as ACDBs, DCDBs must follow IEEE, IEC, BIS standards.In this month, hospitals haven't exported enough units to be banked hence current banked units will be 0. Let's consider 2 conditions and understand how hospitals leveraged solar PV system installation and TOD.First condition is not installing solar systems, second is by planning energy usage and managing import of energy to minimize energy cost.We are referring to values from consumer electricity bills[10].

Condition I:
If we do consider energy tariff applicable for commercial installations without solar system: Here we observed, if we do not install solar power plants and if we do not consider leveraging subsidies given due to TOD tariff, consumers have to pay a hefty bill amount as billing is done to whole consumption.Condition II: If we do consider energy tariff applicable for commercial installations with solar system and by installing net meter: Here we observe that, importing electricity at non-peak hours can significantly reduce cost as electricity is available at subsidized rate.Also energy consumed in this case is significantly lower as solar also generates energy and exports it to the grid, which reduces the import of energy and subsequently the energy bill.
Here energy consumed is 8124 units whereas due to TOD effective cost of importing, this energy gets reduced by Rs.3030, and the remaining demand is fulfilled by output generated by solar.In the first case energy exported by solar is not considered, hence consumers are billed for a greater amount, as 419 units are considered.In the second case the bill reduces, whereas the consumer paid 57 units as a banking charge.

Optimizations using UPS, Motors and Load Shifting
As hospital constantly demands for high power, practically it is not possible for solar power plants to generated energy at peak hours that is during 6:00PM to 10:00PM and rates are higher in this window of time, hence consumer chose to use UPS in this window and sized its UPS at 20KVA which provided them with 4 hours of back up.Now from 10:00PM to 12:00AM and 12:00AM to 6:00 AM i.e. non-peak hours energy is available at subsidized rate, hospital imported energy at the same time (Non-peak hours) and stored in UPS.UPS operates when peak hours start, and units which demand high energy get shifted on UPS, thus reducing the import of energy[10].
Hospital was based on single phase motors for its water pumping system which draws higher current and losses are more due to high current drawn as per I 2 R formula.For example, a 10 horsepower single-phase motor would draw about 20 amps, while a 10 horsepower threephase motor would draw about 12 amps as per P=VI for single phase and P= √3VI for three phases [9].given that the power factor for both motors is the same.Hence all the single phase motors are converted to three phase motors which draws less current for the same power as of single phase motors.Also they reduced the number of motors by efficiently designing the hospital's pumping system.Resulting into a more energy efficient pumping system.

Load shifting or balancing:
As the need of energy for hospitals is more it is more convenient to get distributed connections for which demand charges are more feasible than purchasing one single connection.In this case, the hospital's load is distributed on 3 energy meters instead of a single meter.This facilitates reducing demand charges and is more technically feasible.Now it may happen that load in one department suddenly increases and subsequently energy demand increases, and it may exceed its maximum demand and hospital may need to pay a penalty, to avoid this hospital having manual connection in the control panel to switch load from one meter to another.This system not only saves from exceeding maximum demand but also to manage imports and baking of energy for each meter.
Solar PV systems have helped hospitals to reduce its reliance on the grid and generate its own clean electricity.This is due to installing a solar PV system on the hospital's rooftop.The solar PV system will generate electricity during the day, which can be used to power the hospital's operations.
To gain insights into the energy consumption patterns of hospitals, this section aims to provide a comprehensive analysis of energy utilization and importation.The image shows a bar chart of the average electricity consumed from the grid and the average electricity generated by the solar PV system by the hospital, in kWh.The x-axis shows the months of the year, and the y-axis shows the average electricity in kWh.The blue bars represent the average electricity consumed from the grid by hospital, and the orange bars represent the average electricity generated by the solar PV system.The graph shows that the average electricity generated by the solar PV system exceeds the average electricity consumed from the grid during the months of May to October.This means that the solar PV system is generating more electricity than the hospital is consuming during these months.The graph also shows that the average electricity consumed from the grid is highest during the monsoon months (June to September), and the average electricity generated by the solar PV system is lowest during the monsoon months.This is because solar panels generate less electricity during the monsoon months due to cloudy nature.The graph shows that the solar PV system is helping to reduce the hospital's reliance on the grid and generate its own clean electricity.

Operational Scenarios
A solar-powered hospital with three energy sources (solar power, grid, and DG -Diesel Generator) can have different operation scenarios to ensure reliable and uninterrupted energy supply [4].These scenarios are designed to optimize energy usage, reduce costs, and provide backup power when needed.The hospital primarily relies on solar power for electricity generation during daylight hours.The electricity generated from solar power is used to meet the hospital's energy demands for lighting, air conditioning, medical equipment, and other essential services.The hospital remains connected to the main electric grid to draw power during periods of low sunlight or increased energy demands.During sunny days when the solar power production exceeds the hospital's requirements, the surplus electricity can be fed back into the grid, and the hospital may receive credits or payments through net metering or feed-in tariffs.Payment is paid at the end of the financial year (1 April -31 March) if units in the bank are not nullified against energy imported.If the solar power generation is insufficient to meet the hospital's energy demands during an extended grid outage or, the Diesel Generator (DG) comes into action.The DG starts automatically to provide backup power to the hospital, ensuring continuous operation until the grid power is restored or solar power becomes available again.During peak energy demand periods, such as extremely hot days when air conditioning and cooling requirements are high, the hospital may draw additional power from the grid to supplement the solar energy generation.This helps manage the peak load and ensures that all hospital operations run smoothly.If the hospital's energy demand exceeds the capacity of both the solar power system and the grid supply during extreme peak periods, the Diesel Generator can be brought online to provide additional support and bridge the energy gap.This prevents overloading the solar power system and helps maintain a stable and reliable energy supply.

Building Solar Infrastructure
Capacity and Energy Demand: Start by assessing the hospital's electricity consumption patterns and energy demands.Understand the hospital's average and peak energy requirements to determine the capacity of the PV module needed to generate sufficient solar power.Solar system installers refer to previous electricity bills to get an idea about consumption.

Solar PV system structures and mechanical aspects:
Solar system installations are installed in various ways, some of the popular one are given below [11]: 1. Normal Fixed Tilt. 2. High rise or Elevated structure.

Low Fixed Tilt
Hospital's carpet area is around 7000 sq ft which is a big advantage for solar installers as planning for laying of solar panels can be done easily and is installed in the same way; the hospital has used high rise or their elevated structure to optimize the space they have.By elevating the installation area by 8 ft to 10 ft they utilized the area under installation as canteens and rooms with different facilities for employees.Structure which is used to hold the solar panels should be strong enough to hold the system for its lifetime i.e. for 25 years, structure should be strong enough to bear wind load and should have good stability, along with that seismic load bearing capacity must be in desirable range.As Kolhapur comes under low risk seismic activity, the load bearing range is 0.2 to 0.5g.Live load and wind load are dependent on the weight of the object placed on the structure and dead load is load of material of the structure itself which needs to be considered while designing structures for the holding system.Most popular material used for this purpose is mild steel which is resistive to corrosion and also has high tensile strength i.e. 500N/mm 2 .
Warranty and Service: Ensure that the PV modules come with a comprehensive warranty and that the manufacturer provides reliable after-sales service and support.Typically battery warranty ranges from 3 to 5 years and also life of battery depends upon the cycle of charging and discharging it performed throughout given time, batteries are used for UPS to provide back up during grid outages or during peak hours to reduce energy imports.The depreciation rate for solar power plants in India is 40% over 10 years.Assuming an electricity tariff of Rs.Solar power plants offer a high ROI of 50.17%, with payback periods of less than 3 years if installed correctly.This is due to the high electricity tariffs in India and the declining cost of solar panels.Solar power is a clean and sustainable energy source that can help reduce Bharat's dependence on fossil fuels.
Following image gives a pictorial representation of ROI.Graph explains the rate of recovery of initial investment, ROI increases each year resulting in better returns and proves installing solar PV systems is profitable in the long term despite having high initial investment cost.• Capital cost is the total cost of installing the solar rooftop system • Capacity of the system is the size of the solar rooftop system in kW.
• Tariff rate is the electricity rate that you currently pay.
• Average consumption is the average amount of electricity that you consume in a month.
• O & M cost is the annual cost of maintaining and operating the solar rooftop system.
• Lifetime of the system is the number of years that the solar rooftop system is expected to last Following image gives a pictorial representation of LCoE, it is used to compare cost of electricity generated by a plant over lifetime, given graph explains reduction of cost over lifetime and after a certain point, it is so viable that, cost of generation by solar PV plant gets lower than that of electricity tariff set by distribution company.In this case it is MSEDCL in Maharashtra.To compare this to the tariff rate of Rs. 9.40 per kWh, we can see that the solar power plant would be generating electricity at a cost that is significantly lower than the current tariff rate.This means that the solar power plant would be a viable investment, as it would save the owner money on their electricity bills.

Conclusion
The journey of Masai Medical Foundation's Shri Swami Samarth Hospital stands as a beacon of sustainability in the healthcare industry.By embracing solar PV technology and seamlessly integrating it into their grid-tied systems, this hospital has showcased the transformative power of renewable energy.The results are striking, with substantial energy savings, a remarkable reduction in carbon emissions, and the bolstering of energy resilience.This case study underscores that hospitals, despite their critical need for uninterrupted power, can transition to more eco-friendly and sustainable energy sources without compromising their core mission.At last, sustainable energy isn't just an aspiration, it's a catalyst for change.The transformation of this Kolhapur-based hospital from an energy-dependent institution to a sustainable and eco-friendly entity speaks to the broader potential of renewable energy in revolutionizing critical sectors.Beyond the substantial financial benefits and carbon footprint reduction, it demonstrates the profound impact that forward-thinking energy strategies can have on healthcare.This case study sends a clear message that sustainable energy isn't an idealistic dream but a practical and achievable reality for healthcare institutions worldwide, empowering them to better serve their patients while protecting the planet.

Fig. 1 .
Fig. 1.Flow of Applying for Net Metering for solar PV plant

Fig 2 .
Fig 2. Comparison between electricity generated and electricity imported from grid for each month.

Fig 7 .
Fig 7. ROI of solar PV system 3) Levelized cost of Electricity (LCoE)[8]:To calculate the LCOE of a solar rooftop system for 25 years(Average lifetime of Solar PV system), we need to consider the following factors, • Capital cost of the system • Capacity of the system • Tariff rate • Average consumption • O & M cost • Lifetime of the system The LCOE is calculated using following formula: LCOE = (Capital cost + O & M cost * Lifetime) / (Total energy generated over lifetime)[8].

Table 1 .
Load Estimation of Masai Medical Foundations' Shri Swami Samarth Hospital

Table 2 .
Explains consumer's banking and billing for month of July 2023

Table 3 .
Energy Tariff applicable for commercial installations without solar system

Table 4 .
Energy tariff applicable for commercial installations with solar systems and by installing net meters.
Energy consumed and amount billed can be calculated in following manner:

Table 5 .
Bill reduced due to export of excess energy generated by consumers.
1. Benefits are Multifaceted: The integration of solar PV technology and grid-tied systems brings about a multitude of benefits.Chief among them are significant energy savings, a considerable reduction in carbon emissions, and heightened energy resilience.The hospital's reduced dependency on grid supply and fossil fuels not only lowers operational costs but also contributes to a cleaner and more sustainable environment.2. Valuable Insights for Healthcare Institutions: This case study offers valuable insights and lessons for healthcare institutions worldwide.It underscores the importance of meticulous planning, technological innovation, and strategic utilization of policies like net metering and time-of-day tariffs.Healthcare facilities looking to adopt sustainable energy practices can draw inspiration and guidance from this case study.3. Optimizing Energy Costs is Vital: The hospital's experience emphasizes the critical role of not just policy optimization in energy management but also, the overall space and appliances optimization.By embracing policies like net metering, the hospital effectively harnessed the potential for energy cost reduction.Time-of-day tariffs further enhanced the efficiency of energy consumption, ensuring cost-effectiveness.4. Environmental Impact and Financial Benefits: The hospital's sustainable transformation not only resulted in financial benefits, including favorable payback periods and impressive return on investment, but also made a substantial contribution to environmental sustainability.The reduced reliance on fossil fuels and the associated carbon footprint reduction align with broader decarbonization efforts. 5. Practical Application Matters: The practical application of sustainable energy solutions in a healthcare setting, as demonstrated by Shri Swami Samarth Hospital, validates the viability of these initiatives.Real-world examples like this one serve as compelling models for others contemplating similar transformations.