Sailing on the hydrogen wind! CEEG powers the successful grid connection of China's first 10,000-ton-class renewable hydrogen production project

At 14:38 on December 29, 2023, the Narisong hydrogen step-down substation was energized successfully on the first attempt, and at 18:00 the same day the Narisong PV step-up substation was also energized successfully on the first attempt. This marked the successful grid connection of the Narisong PV hydrogen production demonstration project in Jungar Banner, Ordos, Inner Mongolia — China's first 10,000-ton-class renewable hydrogen project. The project uses the ZHSS-12000/35 24-pulse IGBT hydrogen-production rectifier transformer independently developed, designed and manufactured by CEEG.

01

About the Project

The Narisong project is among Inner Mongolia's first group of integrated wind-solar hydrogen production demonstration projects, and it is the largest 10,000-ton-class renewable hydrogen project in the country — and the world — built as a joint venture between China Three Gorges Renewables (Group) Co., Ltd. and Manshi Investment Group Co., Ltd. The project builds a PV plant on land backfilled from coal mining, with an average annual generation of about 740 million kWh; 20% is delivered directly to the local grid, while the remaining 80% is used for green hydrogen production.

Image source: CTG Renewables

The project installs 15 sets of 1,000 Nm³/h alkaline electrolysis hydrogen production equipment, producing about 10,000 tons of hydrogen and about 80,000 tons of oxygen per year. To safeguard grid security, the project is the first to use mega-ampere-class IGBT power supplies (insulated-gate bipolar transistors) in place of conventional thyristors — a first large-scale application in the global green-power hydrogen production industry. It raises the overall conversion efficiency of the hydrogen production system and serves as a leading example for the technological development of hydrogen production power supplies in China.

Image source: CTG Renewables

02

Core Technology

The CTG Ordos Narisong 10,000-ton-class green hydrogen project is a major undertaking to produce hydrogen from renewable energy. It uses water electrolysis powered by renewables such as solar and wind to produce hydrogen. However, water electrolysis requires high-power DC power, and conventional AC power must be converted through a transformer, making the design and manufacture of the hydrogen-production rectifier transformer one of the project's key technologies.

The ZHSS-12000/35 24-pulse IGBT hydrogen-production rectifier transformer that CEEG engineered for the project was designed from the outset around the project's actual operating conditions, building on CEEG's existing rectifier transformer technology with precise, fine-grained innovation and upgrades — so that the product would satisfy the customer in one pass and enter service quickly, helping convert the investment into returns.

1. Dual-active-part grid-side phase-shifting synchronous voltage regulation structure;

2. Box-top dual-active-part core-lifting structure;

3. Phase-angle deviation and ratio error across tap positions are managed by taking taps from the basic winding while balancing both phase-angle and ratio deviation;

4. Copper-oil temperature difference between the two low-voltage windings: the upper winding's copper-oil temperature rise is typically about 10 K higher than the lower winding's; adjusting the winding oil-path structure effectively reduces the temperature difference between the two;

5. Deviation between the two half-through impedances: adjusting the active-part structure keeps the deviation of the two half-through impedances within a reasonable range.

03

Proven Strength

CEEG has been deeply engaged in the transformer industry for more than 30 years, with rich experience in the design and manufacture of rectifier transformers. Based on the current state of water electrolysis technology in China and abroad, CEEG rectifier transformers rely on rigorous thermal field simulation analysis and CEEG's two core technologies — the high-temperature insulation system and seven-stage temperature control technology — to deliver safe, reliable insulation performance.

CEEG was a lead drafting organization of GB/Z 1094.14-2011, "Power Transformers - Part 14: Design and Application of Liquid-Immersed Transformers with High-Temperature Insulation Materials". Building on DuPont's Nomex® insulation system and the core seven-stage temperature control technology, its insulation performance ranks among the industry's most advanced.

Hydrogen is hailed as the "ultimate energy of the 21st century". Against the backdrop of carbon peaking and carbon neutrality, CEEG continues to consolidate its leading position in rectifier transformers, providing high-quality transformer solutions for renewable green hydrogen production in China and helping accelerate the hydrogen industry into the "fast lane".