What does it take to keep a utility-scale battery energy storage system reliable under these conditions?

In Northwest China's Xinjiang region, a 100MW/400MWh wind-storage project is putting that question into practice. Designed as a four-hour energy storage system paired with wind generation, the project does more than add storage capacity. It helps shift renewable energy across longer time windows, improve renewable energy utilization, and support more stable grid operation.

But achieving that value depends on one fundamental requirement:

The storage system must remain available when the grid needs it.

SINEXCEL supplied 1725kW PCS units, configured into scalable 3.45MW power conversion blocks, to support reliable power conversion under Xinjiang's demanding operating conditions.

Behind the project's stable operation are three key engineering priorities: environmental protection, anti-blockage airflow design, and reliable low-temperature operation.

The Challenge: 4-Hour Storage Meets Extreme Conditions

For utility-scale BESS, extreme weather is not an isolated operational issue. It directly affects equipment protection, thermal management,maintenance requirements, and ultimately asset availability.

1. Extreme Cold: Reliable Operation at -40°C

When temperatures drop to -40°C, the operating limits of power conversion systems are truly tested. Sub-zero environments threaten power electronics with voltage derating, component embrittlement, and delayed signal switching.

2. Severe Sandstorms: A Long-Term Reliability Challenge

Xinjiang's harsh environment also brings frequent sand and dust exposure.

For outdoor power conversion equipment, airborne particles can become a long-term reliability concern—particularly around air intakes and cooling systems. Effective enclosure protection therefore needs to do more than simply prevent water ingress; it must also help keep sand and dust from compromising thermal performance.

3. LDES Safety Management at Scale

Long-duration energy storage introduces safety challenges that shorter-duration systems don't face. With more energy stored per unit and longer charge/discharge cycles, the consequences of thermal runaway or system failure are amplified.

The safety management challenge becomes exponentially more complex. Heating systems must work reliably at -40°C. Enclosures must keep dust out while letting heat escape

The Solution: Engineered for Reliability at Extremes

To address these challenges, SINEXCEL deployed its 1725kW PCS, configured into scalable 3.45MW integrated power conversion units.

Rather than relying on a single protection measure, the solution combines environmental protection, airflow optimization, and intelligent thermal management.

1. IP55 Protection + Removable Protective Padding

The first line of defense is an IP55-rated enclosure combined with removable protective padding designed specifically for harsh winter and desert conditions.

This dual-layer approach delivers several benefits:

• Sand, rain, and snow resistance: The IP55 rating prevents particulates and moisture from reaching sensitive electronics

• Quick-change filters: Removable padding simplifies maintenance, allowing filters to be replaced rapidly without specialized tools

• Reduced weather-related downtime: By preventing weather-related damage, the system maintains higher availability year-round

The result is a PCS enclosure that can handle Xinjiang's sandstorms and freezing winters without compromising performance or requiring excessive maintenance.

2. Anti-Buildup Design for Uninterrupted Cooling

One of the most clever engineering solutions addresses a problem that's easy to overlook: the gradual buildup of sand and snow around air intakes.

Anti-buildup design keeps sand and snow away from air intakes, preventing blockages to ensure optimal cooling.This is the kind of detail that separates equipment designed for generic conditions from equipment engineered for specific extreme environments.

3. Rack-Level Thermal Management: Heating for Extreme Cold

However, the most formidable challenge stems from the extreme cold.

At -40°C, the system must shift from passive environmental defense to proactive thermal control. By leveraging the synergy between PCS inter-charging and internal heating systems, it enables rapid self-heating under sub-zero conditions, keeping batteries at optimal operating temperatures.

Delivering Measurable Value

Since entering full grid connection in January 2024, the project has continued to generate tangible environmental, operational, and financial value:

• Approximately 1.99 TWh of clean electricity transmitted annually

• 172,000 tons of CO2 emissions reduced annually

These results demonstrate how carefully engineered power conversion solutions can contribute not only to successful project delivery, but also to the long-term performance and commercial value of energy storage assets.

A Step Toward Extreme-Environment Energy Storage

The project demonstrates that dependable energy storage is ultimately about more than equipment performance.

By combining climate-adapted engineering, intelligent thermal management, and robust safety measures, SINEXCEL helps turn extreme operating conditions into predictable, long-term system performance—giving utilities, developers, and EPCs greater confidence in the reliability and value of their storage assets.

With over 17 GW of installed energy storage capacity and more than 5,000 deployments across 60+ countries and regions, SINEXCEL continues to support the next generation of utility-scale energy storage with proven, reliable solutions.