Basic situation of customers:

A benchmark for innovation in photovoltaic sector. Taizhou Longi LEERI Solar Technology Co., Ltd., as a wholly-owned subsidiary of Longi Green Energy Technology Co., Ltd., has been deeply engaged in the photovoltaic sector since its establishment in 2015. The company specialises in the research, development, production, and sales of high-efficiency mono-crystalline cells, modules, and related photovoltaic products. Headquartered in Hailing District, Taizhou City, Jiangsu Province, the company operates intelligent production lines with an annual capacity of 4GW. In 2022, it achieved a world record cell conversion efficiency of 26.1% using HPBC structural cell technology and lead the provincial-level major technical renovation project ‘HPBC Photovoltaic Cell Project’. The company not only achieves continuous technological breakthroughs but also fulfills its social responsibilities in environmental protection. Its RO concentrate water reuse technology cuts down 400 cubic meters of fresh water daily, earning it recognition as a Jiangsu Provincial High-Tech Enterprise and certification for its intelligent workshop. However, with the rapid expansion of photovoltaic module production capacity, its manufacturing facilities now demand higher precision in environmental temperature and humidity control. Traditional air conditioning systems are increasingly unable to meet the requirements of precision manufacturing.

Issues that need resolving:

Environmental challenges in precision manufacturing. The production of photovoltaic  cell modules at Taizhou LONGi LEERI involves high-precision processes such as laser etching and screen printing, which are highly sensitive to fluctuations in ambient temperature and humidity. Traditional air conditioning systems confronts three major challenges: firstly, temperature control accuracy is  less than ±1°C, causing fluctuations in cell efficiency; secondly, humidity regulation exhibits significant lag, easily inducing surface condensation on modules; thirdly, equipment energy efficiency ratio remains low, with annual electricity consumption accounting for over 12% of total production costs. Furthermore, photovoltaic workshops typically employ large-scale open layouts, making it difficult for conventional air conditioning systems to achieve precise temperature control across different zones. This results in localized temperature and humidity exceeding acceptable limits, directly impacting product yield rates. These issues become particularly distinct during the high-temperature, high-humidity conditions of summer, forming a key bottleneck restricting production capacity expansion.

Solution:

 WARM Precision Air Conditioning System

Addressing the specific challenges faced by Taizhou LONGi LERRI, WARM Refrigeration Equipment (Shanghai) Co., Ltd. has developed a customized precision air conditioning solution. The core configuration includes:

1. High-precision temperature and humidity control system: Employing microcomputer control technology, achieving temperature control accuracy of ±1°C and humidity control accuracy of ±5% RH. Synergised adjustment of inverter compressors and electronic expansion valves enables threefold enhancement in dynamic response speed. The system built-in enthalpy differential performance laboratory data feedback mechanism can optimize operating parameters for real-time.

2. Modular heat recovery design: Integrated heat recovery modules recover condensation heat during cooling for winter workshop heating, delivering high comprehensive energy efficiency ratios.

3. Intelligent zone control network: A distributed control architecture divides the 20,000m² workshop into 20 independent temperature/humidity zones. Each zone is deployed dedicated sensors and actuators, coordinated with WARM's in-house development of proprietary central microprocessor control system to precisely align energy consumption with process requirements.

4. Multi-layered safety protection system: The unit incorporates twelve protective functions including overload, overcurrent, high-pressure and low-pressure safeguards. Automatic refrigerant leakage detection and remote fault diagnosis systems provide 48-hour advanced warnings of potential risks, ensuring continuous and stable production line in operation.

Customer benefits:

Technology upgrades drives efficiency leaps

Following implementation of this solution, Taizhou LONGi LERRI achieved two significant benefits:

1. Enhanced product quality: Temperature and humidity fluctuations is reduced to one-third of industry standard values, with cell conversion efficiency standard deviation decreasing by 0.15% and cell module yield rate increased to 99.2%, yielding annual quality loss reductions exceeding RMB 8 million.

2. Optimised operational costs: The intelligent control system dynamically adjusts output power according to production rhythms. Combined with heat recovery technology, this achieves substantial annual electricity savings, reduces equipment maintenance costs by 40% and eliminates downtime caused by environmental factors.