The Urgent Energy Needs of Local Hospital

Project Background and Requirements

In 2024, a state-of-the-art specialized hospital located in Kitwe, Zambia, commenced operations, aiming to provide critical healthcare services to the local community. However, the lack of the national grid and instability of diesel generator, posed a significant challenge to the hospital. Unstable power supply frequently impacts emergency care, surgeries, and other critical medical procedures, and power outages can also threaten the lives of critically ill patients. To ensure a stable and reliable power supply for all medical equipment, the project leader looked for a trusted photovoltaic supplier from China. The goal was to design and install a customized solar power system capable of supporting the hospital’s total load.

Before installing the PV system, the hospital used a 250kW three-phase diesel generator to provide uninterruptible power to its loads. The daily diesel fuel expenditure is around USD300(based on 12 hours working time @ 100kW and 1USD/L diesel), and the annual cost is nearly $109,500.
Even though they pay high costs for diesel power generation every day, because there are no energy storage batteries to store electricity, when the generators stop operating, the hospital’s power supply also ceases. Meanwhile, this also undermined the hospital's reputation in the local community and hindered the development of the city's public healthcare standards as well as the ability to safeguard residents' health.

UE Energy Solution

According to the customer’s demand, UE technical team customized a Micro-Grid solution to stablize the power supplying and reduce the working hours and cost of diesel generator. The solution includes 240kW PV, 500kW PCS inverter, et 1576kWh ESS. Ultimately, we successfully helped the customer resolve their electricity shortage and saved $109,500 in diesel costs annually. At the same time, we also configured a 40ft container, using its modular design and high integration to improve the safety of the entire system.

Pre-sales Technical Service

After understanding the client's needs, our engineers conducted in-depth discussions with them. With Google Maps and measurement from customer, we calculated the maximum number of PV panels that could be installed.

Based on the hospital's electricity consumption during the day and at night, confirm the capacity of the energy storage system and select the right size hybrid inverter and other corresponding equipment.

Through the detailed electrical connection diagrams and rooftop PV layouts, customers can directly visualize the connections and structure of the project after installation. These designs not only ensure safety and reliability of the solar solution, while ensure efficient system operation. This visual approach provided them with a clear understanding of the project.

Core Products

How it works?

Scenario 1: Solar Energy Dominance (7:00 AM – 5:00 PM)

During daylight hours with ample sunshine, PV arrays capture solar energy efficiently via their respective MPPT (Maximum Power Point Tracking) controllers. The generated DC power is aggregated by DC Boxes 1, 2, and 3 and then transmitted to the 250kW DC/DC module inside the 40ft container. This DC/DC module precisely converts the “unstable” DC voltage from PV panels into a “stable” DC output.

At this stage, the EMS system (housed in the communication cabinet) continuously monitors three key parameters: solar power generation, hospital load demand, and battery State of Charge (SOC). When EMS detects that solar generation fully meets (and exceeds) the hospital’s real-time load, two processes occur:

• Priority Power Supply: Most of the stabilized DC power is sent to the 500kW PCS (Power Conversion System), which inverts DC to three-phase AC power. This AC power is then routed through the container’s 500kW ATS (Automatic Transfer System) to power hospital loads.
• Excess Power Storage: EMS system identifies “extra power” (when PV generation > hospital load) and directs the PCS to channel this extra DC energy into the 1576kWh energy storage batteries, charging them for later use.

Scenario 2: Battery Discharge for Nighttime Supply (5:00 PM – 7:00 AM Next Day)

After sunset (or during periods of weak sunlight), PV arrays cease generating power. The EMS, upon detecting zero PV input and ongoing hospital load demand (e.g., critical care equipment, refrigeration, emergency lighting), initiates the battery discharge mode.

The energy flow unfolds as:

The energy storage batteries discharge to the 500kW PCS. The PCS converts this DC power into three-phase AC power (matching the hospital’s voltage/frequency requirements).

The AC power travels through the ATS, supplying continuous power to the hospital.

Throughout this process, the EMS closely monitors the battery’s SOC to ensure safe discharge (avoiding over-discharge) while dynamically matching the hospital’s fluctuating nighttime load.

Scenario 3: Diesel Generator Backup (When PV + Storage Fail to Supply)

In extreme scenarios—such as prolonged cloudy weather (PV generates little to no power) or exhausted battery SOC (storage can no longer discharge)—the EMS detects that neither PV nor batteries can meet the hospital’s load demand.

Upon this “power deficiency” detection, the EMS triggers the diesel generator to start. Once the generator is online:

It produces three-phase AC power, which is routed through an ATS cabinet to, ensure an uninterrupted supply to the hospital (especially critical medical loads).

Meanwhile, the EMS monitors the generator’s operational status (e.g., speed, voltage, frequency) to guarantee power quality and remains ready to switch back to PV/battery power once it regains supply capacity.

Future Expansion: Grid Interconnection

The system is designed with a reserved interface for the 400V grid (in the future). When the local 400V grid is built, the system will enable grid-interactive operation, unlocking two key capabilities:

Power Export: When PV/ESS generate excess power (and the grid permits), surplus energy can be fed into the grid for power trading, creating economic value.

Power Import: If PV/storage/diesel generation all fall short of meeting the hospital’s load, the system can draw power from the grid, ensuring 100% reliability.

This grid integration transforms the system into a “multi-energy coordinated network” (combining PV, storage, diesel, and grid power), maximizing energy efficiency and supply stability for the hospital.

Advantages of 40ft Containerized Battery Energy Storage System

This containerized battery energy storage system integrates multiple devices, including air conditioning system, fire protection system, lighting system, monitoring system, battery rack, EMS cabinet battery monitoring system, DC control cabinet, and PCS system. The container body also includes an escape door, an air inlet & outlet system, etc.

• Air conditioning system ensures the operating temperature of the battery;
• Fire protection system ensures the safety of the container;
• Monitoring system can detect the status of the container in real time;
• EMS system can monitor the voltage, temperature, and other information of the battery in real time, and can also control the charging and discharging of the battery.
• PCS system can make the battery and the grid seamlessly connected.

It is also portable, flexible, expandable, and disassembled. It conforms to ISO standard dimensions, making it easy to transport by sea and land.

The advantage of containers is that they can be "plug and play". We pre-assembled all core components (batteries, PCS, BMS, fire protection systems, etc.) in the factory. After receiving the goods, customers only need to connect them to solar panels, loads, or generators to put them into operation, which greatly shortens the construction period.

Project Results and Benefits

Since the installation of the UE system, the hospital has experienced remarkable improvements. It now enjoys a stable power supply, PV system generates 800-1200kWh of electricity per day. The 1576kWh ESS plays a vital role in maintaining a 99% power supply availability. An Automatic Transfer Switch (ATS) automatically controls the diesel generator, ensuring seamless power transitions.

The Energy Management System (EMS) allows for the intelligent operation of all electrical equipment in the system. Hospital staff can manage the energy consumption most conveniently, optimizing costs and ensuring the continuous operation of critical medical devices.

Operation and After-sales Service

Prior to shipment, the entire energy storage system undergoes stringent factory acceptance testing — covering performance, safety, and system compatibility — to ensure “plug-and-play” readiness upon arrival at the site. To streamline on-site deployment, UE provides a comprehensive suite of resources: detailed installation manuals, step-by-step instructional videos, technical data sheets, and user-friendly operation guides for each product.

UE is dedicated to long-term customer success through advanced remote monitoring capabilities. Our technical team can track the system’s real-time performance (including solar power generation, battery health, and load distribution) via a centralized digital platform. In the event of issues, we offer remote support for tasks like battery cell balancing, troubleshooting, and performance optimization — minimizing downtime and ensuring continuous operation.

In this project, we have helped customers solve some common after-sales problems:

- Remotely guiding the installer through battery commissioning to achieve lithium battery calibration.

- When abnormal string voltage was detected in the PV array, UE team quickly helped the customer adjust the string connection method to restore optimal performance.

- When customers needed to switch to diesel power (after a complete battery discharge) and was unfamiliar with ATS operation, we provided timely assistance to ensure a seamless power transition.

Conclusion

UE’s 240kWp + 1.5MWh ESS project is a landmark success in replacing diesel power with clean, reliable solar energy for critical healthcare infrastructure. By solving the hospital’s urgent need for uninterrupted power—previously hampered by frequent outages and exorbitant diesel costs—our customized PV+ESS solution has not only guaranteed 99% power availability for life-saving medical equipment but also delivered tangible economic and environmental benefits.

Compared to the diesel-dependent setup, the system now cuts annual diesel expenses by over $109,500 with a around 4 year payback period, creating long-term value for the hospital. Its modular design, intelligent EMS, and easy transportation make it adaptable to diverse off-grid or weak-grid scenarios—from hospitals and clinics to industrial facilities and rural communities.

This project exemplifies UE’s commitment to providing customer-centric, sustainable energy solutions that solve real-world challenges. For global clients grappling with unstable grids, high fossil fuel costs, or carbon reduction goals, UE’s PV+ESS systems offer a proven alternative to diesel power—empowering businesses and communities to thrive with clean, reliable energy.

We look forward to partnering with more organizations worldwide to accelerate the transition from diesel to solar, contributing to a greener, more resilient energy future while supporting critical sectors like healthcare, education, and manufacturing.