Company Profile

Background

Taiwan produces roughly 22 million tonnes of crude steel per year, and the steel sector accounts for nearly 20 percent of the country's industrial carbon emissions. The Linhai industrial area in Kaohsiung alone concentrates more than 60 percent of Taiwan's integrated steelmaking capacity. As the EU Carbon Border Adjustment Mechanism moves toward full levy in 2026 and Taiwan's own 2050 net-zero pathway names steel as a priority transition sector, the traditional blast-furnace route faces unprecedented decarbonisation pressure. In early 2023, Hengmao International was commissioned by the Kaohsiung City Government Bureau of Economic Development to plan Taiwan's first hydrogen-based direct reduced iron pilot line coupled with a direct air capture system inside an operating electric-arc-furnace steelworks. The objective was to validate green-hydrogen-based iron reduction while simultaneously integrating negative-emissions technology through DAC in the same industrial site.

Participating Bodies and Roles

Hengmao International served as EPC contractor and system integrator, overseeing specification, procurement, installation, piping, and commissioning for both the H2-DRI pilot line and the DAC system. On the academic side, National Cheng Kung University's Departments of Materials Science and Engineering and Resources Engineering led hydrogen-reduction kinetics modelling, furnace-atmosphere optimisation, DRI and HBI quality analysis, and DAC solid-sorbent regeneration testing. National Sun Yat-sen University's Department of Chemical and Materials Engineering was responsible for DAC sorbent surface modification and full-system life-cycle carbon assessment. The Materials and Chemical Research Laboratories of ITRI supported the project with high-temperature hydrogen safety monitoring and palladium-membrane purification technology, incorporating the work into its net-zero key-technology development programme.

On the government side, the Kaohsiung City Government Bureau of Economic Development served as the competent authority, coordinating land use, environmental review, and urban-planning amendments. The Industrial Development Administration under the Ministry of Economic Affairs provided equipment subsidies and finance guarantees through a high-carbon-industry transformation programme. The National Science and Technology Council funded the NCKU and NSYSU research under its net-zero technology initiative, while the Climate Change Administration of the Ministry of Environment handled methodology certification for DAC-captured CO2 and alignment with Taiwan Carbon Exchange voluntary reduction projects. CPC Corporation, Taiwan, also signed a back-up hydrogen supply agreement based on by-product hydrogen from the adjacent LNG terminal.

Engineering Design and Technology Pathway

The project followed a dual-track decarbonisation concept: source-side reduction through hydrogen replacing coke in ironmaking, and negative emissions through DAC removing CO2 from the atmosphere. On the H2-DRI track, Hengmao built a shaft-furnace pilot line rated at 15,000 tonnes of DRI per year inside a partner EAF mill. The furnace stands 18 metres tall with a 3.2 metre inner diameter, lined with high-temperature alumina brick and a high-nickel alloy shell, operating at 850-950°C. The reducing-gas programme started with a transitional 70 percent hydrogen and 30 percent natural-gas blend and was designed to move gradually toward 100 percent hydrogen. Hydrogen came from three supply routes: a 2 MW on-site alkaline electrolyser powered by green electricity under a Taipower renewable contract; trucked green hydrogen from Hengmao's Pingtung Dawushan biogas-reforming project; and industrial by-product hydrogen from CPC Corporation as a back-up source.

A real-time furnace-monitoring system designed with NCKU transmitted temperature gradients, metallisation rates, and gas-composition data every 15 seconds into a digital-twin platform. Tests showed that at 900°C and a hydrogen partial pressure of 0.65 atm, premium 10-16 mm iron-ore pellets reached a metallisation rate above 94 percent within four hours, with DRI carbon content below 1.5 percent. Hot DRI was then fed directly into the existing EAF, blended with scrap at a 40:60 ratio, reducing crude-steel emissions from 2.1 tonnes CO2 per tonne via the blast-furnace route to about 0.45 tonnes CO2. On the DAC side, Hengmao installed a modular solid-sorbent system with an annual capture capacity of 500 tonnes of CO2. Twelve adsorption-desorption modules used amine-functionalised honeycomb structures, and regeneration relied entirely on low-grade steam and hot-water loops recovered from H2-DRI and EAF waste heat. This integration allowed DAC desorption to run with minimal primary-energy penalty, while captured CO2 was split between nearby petrochemical CCU use and certified carbon-credit routes through Taiwan Carbon Exchange.

Results and Impact

The H2-DRI pilot line completed commissioning in June 2025 and passed a 30-day stable-operation verification in October 2025. The DAC system began adsorption testing in March 2025 and had captured 320 tonnes of CO2 by the end of that year. By the end of March 2026, the pilot line had produced around 9,800 tonnes of DRI and about 24,500 tonnes of low-carbon crude steel through downstream EAF melting, with average emissions of just 0.48 tonnes CO2 per tonne of crude steel, around 77 percent below the traditional blast-furnace route. Because DAC desorption ran on recovered heat, operating power demand stayed near 250 kWh per tonne of CO2, below the 300-400 kWh range commonly seen in comparable international systems.

Total capital expenditure was about NT$1.8 billion, with 35 percent covered by public subsidies. Annual value was projected at NT$240 million in low-carbon steel premium, NT$48 million in carbon-credit income, and NT$36 million in waste-heat power and energy savings, bringing combined annual benefit above NT$320 million with a payback period of roughly 7.5 years. The project created 65 full-time technical roles, 200 construction-period jobs, and helped NCKU and NSYSU train 28 graduate researchers in green steel and carbon capture. Most importantly, it proved the technical and economic feasibility of coupling hydrogen ironmaking with waste-heat-driven DAC inside an existing Taiwanese steelworks, giving the sector a scalable decarbonisation blueprint for future commercial deployment.

Background

Taiwan generates approximately 2,100 tonnes of household and commercial food waste every day. For many years the main disposal routes were pig-feed use and composting. In 2018, however, African Swine Fever alerts led the Council of Agriculture, now the Ministry of Agriculture, to ban the feeding of uncooked food waste to pigs. Counties and cities were suddenly left with a major treatment-capacity gap. At the same time, the Environmental Protection Administration, now the Ministry of Environment, advanced its resource-circulation and zero-waste policy, encouraging local governments to turn food waste into biogas power through anaerobic digestion and move from simple waste treatment to renewable-energy production.

In response, the Taichung City Environmental Protection Bureau and the Miaoli County Environmental Protection Bureau each launched planning commissions for food-waste anaerobic digestion power plants in early 2019 and brought Hengmao International into their core teams. Drawing on more than thirty years of M&E EPC experience and prior livestock-biogas delivery in Pingtung, Hengmao took full EPC responsibility for both plants from feasibility study, EIA technical advisory, basic and detailed design, equipment procurement, civil works, and M&E installation through to commissioning and handover. The Taichung plant secured its power-generation licence and entered commercial operation in December 2023, becoming Taiwan's first bioenergy power plant to run on urban household food waste as its sole feedstock, complete the full EIA process, and achieve stable grid-connected power sales. The Miaoli Zhunan plant followed in June 2024.

Participating Bodies and Roles

The industry-academia-government structure was highly symmetrical across both plants. The Taichung City and Miaoli County Environmental Protection Bureaux each acted as the competent authority, handling land procurement, food-waste collection systems, and operational feedstock dispatch. The Bureau of Energy under the Ministry of Economic Affairs approved both projects for the agricultural-waste biomass power feed-in tariff at NT$5.1407 per kWh for twenty years and also provided equipment-investment offsets. The Resource Circulation Administration of the Ministry of Environment funded front-end sorting and collection-equipment upgrades through its diversified food-waste utilisation subsidy programme.

The academic arm came from National Chung Hsing University, where the Department of Environmental Engineering and the Department of Bio-Industrial Mechatronics Engineering formed a joint R&D team for food-waste characterisation, seasonal composition tracking, anaerobic microbial regulation, digestate liquid-fertiliser feasibility, and full-system life-cycle carbon analysis. The Green Energy and Environment Research Laboratories of ITRI supported engine-efficiency verification, grid power-quality testing, and consultancy on trace siloxane removal from biogas. Hengmao deployed approximately 180 engineering staff across the two projects and operated through a shared design platform with locally differentiated construction, meaning the core process logic was common while equipment selection and civil layout were tailored to local feedstock composition, climate, and site constraints.

Engineering Design and Technology Pathway

Both plants followed Hengmao's four-stage process of pre-treatment, anaerobic digestion, biogas power generation, and digestate valorisation, while being tailored in scale and detail to local conditions.

Taichung Waipu Plant

The Taichung plant was designed for 200 tonnes of household food waste per day, collected from sanitation teams across Taichung's 29 districts as well as contracted commercial sources including 15 large catering operators and three wholesale produce markets. Its pre-treatment section used two parallel feed lines equipped with chain-plate conveyors, twin-shaft shredders, magnetic separation, air-based plastic removal, and pulping mixers. After size reduction to below 30 mm, vibrating screens removed residual glass and grit, while recycled digestate liquid adjusted solids content to 10-12 percent before pumping to the digesters. Non-digestible contaminants such as plastic bags, disposable cutlery, and bone fragments accounted for roughly 8-10 percent of incoming weight and were compressed and sent to the existing incinerator. Hengmao's design highlight was a fully enclosed negative-pressure deodorisation system that held the pre-treatment building at minus 15 Pa and treated all exhaust through chemical scrubbing, biofiltration, and activated-carbon adsorption, keeping boundary odour below 50 OU/m3 against a regulatory limit of 80 OU/m3.

The anaerobic digestion section comprised three fully mixed 3,500 m3 CSTR digesters in welded carbon-steel shells with insulation and steam-coil heating, operating at 38 plus or minus 1 degrees Celsius with a 28-day hydraulic retention time. The three-digester arrangement was run as two active and one standby vessel. Guided by NCHU's microbial-community analysis, Hengmao adopted a gradient acclimatisation start-up regime, beginning at an organic loading rate of 2.0 kg VS per m3 per day and increasing by 10 percent every two weeks until the design rate of 4.5 kg VS per m3 per day was reached after roughly four months, avoiding acidification risk. Under stable operation the site produced around 12,000 Nm3 of biogas per day at 60-63 percent methane. After desulphurisation, dewatering, and siloxane removal, the gas was sent to two 1.2 MW gas-engine generator sets with heat recovery, delivering around 16.8 million kWh per year. After about 18 percent in-house consumption, surplus electricity was sold to Taipower, generating roughly NT$69 million annually.

Digestate valorisation became a second standout feature. Dewatered solids at about 65 percent moisture were sent into Hengmao's enclosed aerobic composting tunnel at 15 tonnes per day and matured for 21 days under forced aeration at 55-65 degrees Celsius. The final product, branded GreenWotu, met the Ministry of Agriculture's organic-fertiliser standard and was sold through the local farmers' association to taro, grape, and mushroom growers. Liquid digestate was treated through ammonia stripping and membrane filtration before reuse as irrigation water for on-site landscaping and as dilution water for the digesters, allowing the plant to operate with zero liquid effluent discharge.

Miaoli Zhunan Plant

The Miaoli plant was designed at a smaller 80 tonnes per day, using household food waste from 18 townships and municipalities in Miaoli County plus commercial food waste from six employee canteens in the Zhunan Science Park. Its overall process followed the same architecture as Taichung but at reduced scale: two 2,000 m3 CSTR digesters in an active-standby arrangement and one 600 kW biogas generator set. Annual power output was approximately 4.2 million kWh, generating around NT$17.3 million in feed-in tariff revenue.

Its signature addition was a 250 kW / 500 kWh LFP battery energy storage system paired with 200 kWp of rooftop solar, forming a combined biogas, PV, and storage microgrid. This configuration came from Miaoli County's longer-term ambition to use the site as a technical validation platform for resilient distributed energy serving remote coastal communities. When distribution-feeder faults or typhoon-related outages occur, the microgrid can switch automatically to island mode and maintain plant operation plus emergency power to a nearby clinic and fire station for more than eight hours. During Typhoon Gaemi in July 2024, the site completed an islanding transition within 0.3 seconds after the Taipower feeder tripped and sustained supply for eleven hours until grid restoration.

Results and Impact

By the end of April 2025, the Taichung plant had been in stable commercial operation for sixteen months, processing 89,600 tonnes of food waste, generating 22.4 million kWh, and producing 4,200 tonnes of GreenWotu organic fertiliser, with annual carbon reduction estimated at 18,500 tonnes CO2e. The Miaoli plant had operated for ten months, processing 22,400 tonnes of food waste, generating 3.5 million kWh, and delivering annual carbon reduction of about 4,600 tonnes CO2e. Together, the two sites were capable of treating roughly 100,000 tonnes of food waste per year and reduced food-waste disposal pressure by 85 percent in Taichung and 72 percent in Miaoli.

Socially, the two plants created 68 full-time operating positions, 48 in Taichung and 20 in Miaoli, with more than 80 percent filled by local residents. Hengmao and NCHU jointly hosted twelve community briefings and six campus environmental-education events, and both facilities were opened as certified environmental-education sites receiving more than 150 visiting groups per year. Local agricultural associations reported that 320 farming households had adopted GreenWotu, with taro fields showing a 1.2 percentage-point increase in soil organic matter and about 30 percent lower chemical-fertiliser use.

On technical replication, Hengmao compiled the twin-city design drawings, equipment specifications, operating manuals, and EIA strategy documents into a standardised food-waste bioenergy plant delivery package and jointly published two international journal papers with NCHU. The package has already become a reference for similar planning work in Changhua and Yunlin, while Pingtung and Taitung have invited Hengmao to assess co-digestion plants combining food waste with agricultural residues. The Taichung Waipu plant, as Taiwan's first operating urban food-waste bioenergy benchmark, received the Ministry of Environment's Third Resource Circulation Outstanding Facility Award in October 2024 and the Bureau of Energy's Renewable Energy Promotion Excellence Award. Through this programme, Hengmao demonstrated to Taiwan that food waste is not rubbish but energy in the wrong place.

Background

Changhua County and Yunlin County are Taiwan's two highest-value agricultural and livestock-producing counties. Changhua is a major base for flowers, vegetables, and rice, generating about 280,000 tonnes of agricultural residues each year, including rice straw, rice husks, floral prunings, and spent mushroom substrate bags. Yunlin has the country's highest pig-farming density, with more than 1.3 million pigs producing over 3.8 million tonnes of manure and wastewater annually, alongside roughly 220,000 tonnes of crop residues from rice, peanuts, and garlic. For many years, open burning remained the dominant disposal route for these residues, driving repeated PM2.5 spikes across the central plains after every autumn harvest. Small farm biogas pits existed in some swine operations, but outdated hardware and weak maintenance kept actual recovery below 15 percent, while large volumes of organic wastewater continued to degrade waterways in the Zhuoshui River basin.

In 2020, guided by the Ministry of Agriculture's circular-agriculture agenda and the Bureau of Energy's agricultural green-energy co-development policy, the Changhua County Government and Yunlin County Government jointly proposed a cross-county programme and appointed Hengmao International as EPC contractor and system integrator. One demonstration park was placed in Xihu Township, Changhua, with thermochemical gasification of agricultural residues as its core, while the second was developed in Lunbei Township, Yunlin, around centralised pig-farm biogas treatment and solar-livestock integration. Through shared resource scheduling and common engineering logic, the two sites were designed to operate as a dual-core circular-agriculture alliance spanning two counties.

Participating Bodies and Roles

On the government side, the Agriculture Departments of the Changhua County Government and the Yunlin County Government each led the programme within their own county, coordinating farmland-use conversion, livestock-site arrangements, and farmer participation. The Central District Inspection Brigade of the Ministry of Environment supported both sites on EIA work and operational environmental monitoring. The Bureau of Energy provided solar-PV support and the agricultural-residue power feed-in tariff at NT$5.1407 per kWh through its agricultural green-energy co-development plan, while the Livestock Division of the Ministry of Agriculture covered capital expenditure for centralised biogas-treatment facilities through its manure-resource utilisation subsidy.

The academic arm was formed by National Chung Hsing University and National Yunlin University of Science and Technology. NCHU's Department of Bio-Industrial Mechatronics Engineering focused on gasification kinetics, syngas optimisation, and tar-cracking catalyst development, while YunTech's Department of Environmental and Safety Engineering handled anaerobic co-digestion tuning, digestate land-application safety, and full-system life-cycle carbon analysis. The Green Energy and Environment Research Laboratories of ITRI supported engine-performance verification, grid-quality testing, and online monitoring for tar and trace sulphur compounds in the syngas stream. Hengmao deployed around 150 project personnel across both sites and delivered the full EPC chain from geotechnical survey and foundation design through structural works, piping, equipment erection, and SCADA integration.

Engineering Design and Technology Pathway

The programme combined two complementary park typologies. Changhua Xihu focused on thermochemical gasification of agricultural residues and supporting solar generation, while Yunlin Lunbei combined centralised manure treatment, anaerobic digestion, biogas power, solar-livestock facilities, and fertigation-based nutrient recycling. Together they formed a cross-county engineering model that linked agricultural residues, livestock waste, electricity generation, and material recirculation into one coordinated system.

Changhua Xihu Park

The Xihu park covers 3.2 hectares on idle farmland next to the Xihu Township Farmers' Association warehouse district. Its core asset is a downdraft fixed-bed gasifier designed for 60 tonnes of agricultural residues per day. Feedstock is supplied through township-level contracts and consists of compressed rice-straw bales, rice husks, spent mushroom substrate bags, and floral prunings. Hengmao designed a full pre-treatment line at the park entrance: straw is chopped below 50 mm, husks pass through cyclone de-sanding, substrate bags are opened and de-plasticised before blending with wood chips, and all streams move through a belt dryer that reduces moisture to below 15 percent before screw-fed charging into the gasifier.

The gasifier itself was designed and fabricated by the Hengmao team using kinetic models developed with NCHU. It has a 2.8 m internal diameter, a 4.5 m effective reaction height, and operates at 750-850 C with preheated air as the gasification agent. Feedstock enters continuously from the top and passes through drying, pyrolysis, reduction, and oxidation zones, producing syngas at about 650 C with H2 at 18-22 percent, CO at 20-24 percent, CH4 at 2-4 percent, and the balance as N2 and CO2. Because the downdraft layout drives tar-laden gas back through the hot oxidation zone, raw-gas tar is kept below 100 mg/Nm3. After cyclone dust removal, venturi scrubbing, and activated-carbon polishing, tar falls below 10 mg/Nm3 and H2S below 30 ppm, allowing the stream to feed two 800 kW syngas engine-generator sets. Exhaust heat is recovered into 120 C saturated steam for the belt dryer, creating a combined heat-and-power loop. Annual generation is about 10.5 million kWh, with around 20 percent consumed on site and the balance sold under feed-in tariff terms for about NT$43.2 million per year. Bottom ash, roughly 5 percent of feed mass and rich in potassium, phosphorus, and silica, is certified for reuse as a soil-improvement product. Hengmao also installed a 2.5 MWp ground-mounted solar field on the park's southern side, using high-efficiency monocrystalline PERC modules and single-axis trackers to add around 3.25 million kWh per year through the same 22.8 kV interconnection.

Yunlin Lunbei Park

The Lunbei park covers 5.8 hectares on county-owned livestock-zone land near the Lunbei meat market in Yunlin. Its mission was to solve the long-running manure-treatment problem faced by 47 small and medium pig farms across Lunbei, Erlun, and Mailiao, each typically raising between 500 and 3,000 pigs. Hengmao's engineering answer combined central collection, shared digestion, and solar-powered livestock housing. A central biogas treatment plant was built together with 28 km of buried HDPE manure pipelines and six relay pumping stations, while four 15-tonne vacuum tankers served the nine farms located more than 5 km away. The design capacity was 450 tonnes per day of manure and wash water. After solid-liquid separation, the solid fibre fraction at about 22 percent solids could be redirected as auxiliary gasifier feed or compost feedstock, while the liquid phase moved into four 4,000 m3 CSTR digesters.

The digesters operated in a three-active, one-standby mode at 37 plus or minus 1 C with a 22-day hydraulic retention time. Under guidance from YunTech, the digestion recipe blended 85 percent liquid swine manure with 15 percent rice-husk fines transferred from Xihu on a volatile-solids basis, balancing carbon and nitrogen into a 25-30 C/N range and stabilising daily biogas production at roughly 15,000 Nm3 with methane content between 58 and 62 percent. After desulphurisation and dewatering, the gas was fed to three 1 MW engine-generator sets, yielding about 21 million kWh per year and around NT$86.3 million in annual power-sale revenue. The park's second signature feature was its solar-livestock demonstration zone: four enclosed modern pig houses, each rated for 2,000 hogs, were built in compliance with Ministry of Agriculture rules for green-energy livestock facilities. Their roofs carried 3.2 MWp of PV in total, generating about 4.16 million kWh per year. Negative-pressure evaporative cooling kept indoor temperatures between 24 and 28 C, while automated feeding, watering, and scraper-based manure collection improved survival by about 5 percent and feed-conversion efficiency by 8 percent. Manure moved through sealed piping straight to the biogas plant, and digestate was returned through fertigation stations to 12 hectares of forage-maize fields, completing a loop of feed, livestock, manure, biogas, electricity, and nutrients.

Results and Impact

The Xihu park completed commissioning in March 2024 and entered commercial operation in May, while the Lunbei park, facing heavier pipeline complexity, completed integrated system testing in September 2024 and began operation in November. By the end of April 2025, Xihu had processed 21,600 tonnes of agricultural residues, generated 8.75 million kWh, produced 1,080 tonnes of ash-based soil improver, and added 2.71 million kWh from solar. Lunbei had processed 202,500 tonnes of livestock manure, generated 17.5 million kWh of biogas power, added 3.47 million kWh from solar-livestock assets, and delivered digestate fertigation across 12 hectares of forage land. Combined annual carbon benefit was estimated at about 42,000 tonnes CO2e, including around 185 tonnes of avoided PM2.5 emissions from reduced open burning. Monitoring data in Changhua showed autumn PM2.5 daily averages falling 18 percent relative to the pre-operation period, while Yunlin's main drainage channels recorded BOD and ammonia reductions of 62 percent and 55 percent.

Total capital expenditure across the two parks was about NT$2.2 billion, with public subsidies covering 38 percent. For the 47 participating pig farms, reduced manure-treatment fees plus revenue sharing from power sales translated into roughly NT$850,000 in annual savings and added income per farm. The success of the four solar-livestock buildings has already led another 23 Yunlin pig farms to apply for inclusion in a second expansion phase. Together, the two parks created 92 full-time jobs and 180 temporary construction roles.

On talent development and technical diffusion, Hengmao worked with NCHU and YunTech to launch a summer credit programme on circular-agriculture green-energy engineering, training 45 graduate students. The partnership also produced four international journal papers and three patent applications related to gasifier design and co-digestion ratios. Hengmao compiled the design drawings, equipment specifications, and operating manuals of both parks into a standardised circular-agriculture green-energy park delivery package and submitted it to the governments of Changhua, Yunlin, and Chiayi as a baseline for second-phase planning. Pingtung and Taitung have also requested customised assessments to explore how the same three-in-one model can be replicated in other agriculture-intensive regions. Through this dual-park programme, Hengmao demonstrated that circular agriculture is not a slogan but a buildable, profitable, and repeatable green-energy engineering solution.

Foreword

Pingtung is one of Taiwan's most important pig-farming counties, with roughly 1.15 million pigs and the country's densest concentration of large-scale farms. For decades, however, manure wastewater from those farms placed chronic pressure on the Donggang, Linbian, and Ailiao river basins. The policy turning point came during former Magistrate Tsao Chi-hung's administration, when enclosed anaerobic digestion and biogas recovery were elevated from environmental mitigation tools to a central part of county energy strategy.

Under that policy line, Pingtung became the first county in Taiwan to systematically frame pig manure as an energy asset rather than an environmental liability, and in 2016 created a dedicated inter-agency green-energy office to carry biogas work forward alongside county solar initiatives. The current Green Hydrogen South programme is positioned as the next step in that twenty-year policy arc: extending biogas-to-power into biomethane and then into green hydrogen.

Policy and Market Context

Taiwan's feed-in tariff for biogas power has risen sharply since the Renewable Energy Development Act took effect, while the Ministry of Agriculture's pig-industry upgrading programme expanded incentives for farm-scale digesters. By the end of 2024, hundreds of biogas power and utilisation facilities had already been deployed nationally. Even so, Pingtung's existing recovery network still leaves a large share of the county's manure resource outside the power system.

At the same time, the National Development Council's 2050 net-zero pathway identifies hydrogen as a strategic pillar, and southern Taiwan already has clear downstream demand in ports, petrochemicals, semiconductors, logistics, and demonstration transport. That combination gives the livestock-biogas to biomethane to green-hydrogen chain a particularly strong regional logic in Pingtung.

Project Overview

The programme is anchored in a 14-hectare livestock zone near the Pingtung Agricultural Biotechnology Park and is structured around a special-purpose operating company backed by 18 large pig farms and strategic county investment. Hengmao serves as EPC integrator across two phases: first, a manure collection network and 10 MW biogas power plant; second, biogas upgrading and a green-hydrogen conversion centre. The project scope covers slurry from approximately 500,000 pigs, or about 43 percent of the county herd, with total investment set at roughly NT$3.8 billion.

Technical Configuration

Hengmao's engineering design is built on three integrated stages: centralised co-anaerobic digestion, biogas upgrading, and steam-methane reforming for green hydrogen. The front-end system links the participating farms through 32 kilometres of enclosed transfer mains and six booster stations. Six 8,000 m3 mesophilic CSTR digesters form the fermentation core, and optional co-digestion inputs from commercial food waste and slaughter residues are used to raise methane productivity. The design target is about 100,000 Nm3 of raw biogas per day with methane content of 60 to 65 percent.

Around 30 percent of the gas stream is upgraded through PSA into pipeline-grade biomethane and then reformed through modular SMR with carbon capture and utilisation. The green-hydrogen target is about 1,200 kilograms per day at 99.97 percent purity, with quality validation led by ITRI and National Pingtung University of Science and Technology. Digestate reuse remains part of the system design as well, with annual liquid return to county afforestation and crop-transition areas under Taiwan's manure resource-utilisation rules.

Stakeholder Architecture and Milestones

The alliance combines county land and permitting support, central subsidies from the Ministry of Agriculture, Bureau of Energy, and Ministry of Environment, Taipower as the power purchaser, and ITRI plus NPUST as the technical-verification and talent-development backbone. The current milestone path targets EIA approval and power-purchase agreement signing in 2026, first-phase biogas generation in 2027, installation of PSA and SMR modules in 2028, and full commercial operation in 2031.

Risk Management and Expected Benefits

The project's principal controls focus on enclosed collection, odour suppression, diversified co-digestion backup feedstock, and long-term supply contracts with the participating farms. On the market side, electricity revenue is anchored by the feed-in tariff, while hydrogen offtake is positioned for long-term supply to agricultural-biotech, logistics, and regional demonstration users in southern Taiwan.

Expected annual benefits include around 65 million kWh of renewable electricity, roughly 400 tonnes of green hydrogen, and carbon reduction of about 185,000 tonnes CO2e. The programme is also designed to improve watershed water quality, reduce odour risk through enclosed handling, and create a new revenue stream for livestock operators through long-term feedstock agreements and power or hydrogen value sharing. It extends Pingtung's biogas legacy from waste control into a regional hydrogen infrastructure base for southern Taiwan.

Background

Taitung's waste incinerator is one of the most difficult chapters in Taiwan's waste-governance history. The plant was completed in 2005 with two furnace lines and a design capacity of 300 tonnes per day, but BOO disputes, illegal-structure findings, local resistance, and council opposition kept it idle for more than a decade. An arbitration ruling in 2011 forced the county government to acquire the site, after which maintenance costs continued while equipment corroded.

A first rehabilitation phase finally brought the facility into operation in early 2023, after replacement of key cooling and air-pollution-control equipment. By mid-2025 it had processed more than 160,000 tonnes of waste and generated over 77 million kWh. Phase I, however, was fundamentally about getting the furnace running. Phase II shifts the goal toward energy efficiency, heat recovery, residue valorisation, and carbon management, with Hengmao tasked to convert the centre into eastern Taiwan's first integrated renewable-energy and resource-circulation power facility.

Participating Bodies and Roles

Hengmao acts as EPC contractor across specification, procurement, demolition of obsolete systems, installation, pipe integration, and commissioning. National Taitung University provides engineering and environmental assessment for bottom-ash reuse, while National Cheng Kung University supports fly-ash melting and vitrification validation. ITRI assists on power-island performance verification and smart-grid quality tests. The Taitung County Environmental Protection Bureau leads the programme with subsidy support from the Ministry of Environment's Resource Circulation Administration, the Bureau of Energy, and Taipower's interconnection works.

Scope of Works and Technology Pathway

The upgrade is divided into five modules under a one-line-operating, one-line-refurbishing strategy. The first module replaces the legacy 7.5 MW turbine with a 9.5 MW condensing unit and lifts steam conditions from 300 C and 20 bar to 400 C and 40 bar, increasing net generation efficiency from 18 percent to 26 percent. The second module adds a three-stage heat-recovery chain: flue-gas to feedwater recovery, a 350 kW ORC unit for low-grade heat, and low-temperature hot-water supply to nearby university research greenhouses and on-site services.

The remaining modules cover bottom-ash sorting and recycled aggregate production, local fly-ash melting into vitrified slag, and a new on-site intelligence layer. Hengmao's design introduces a full bottom-ash recovery line targeting about 15,000 tonnes per year of reusable aggregate, a 12-tonne-per-day electric-arc fly-ash melting furnace, 1.8 MWp of rooftop and canopy solar, and an IIoT operations platform with more than 800 sensors for combustion optimisation, carbon accounting, and remote inspection.

Results and Impact

The programme targets full completion in the second quarter of 2028 after an investment of about NT$1.28 billion. Once complete, total annual generation is expected to rise from about 57 million kWh to roughly 88 million kWh including ORC and solar output, while the site becomes one of Taiwan's top-performing incinerators by net efficiency. Bottom-ash reuse is targeted at 83 percent, fly ash at 100 percent local melting and stabilisation, and annual carbon reduction at about 15,000 tonnes CO2e.

More importantly, the project changes the meaning of the site. An idle public facility long seen as a failure is recast as eastern Taiwan's first integrated waste, power, resource-circulation, and carbon-management platform. The programme is also expected to create 38 full-time technical roles, 120 construction jobs, and a reusable technical package for other aging municipal incinerators in Taiwan.

Background

Kinmen is a fully isolated power island with no cable connection to Taiwan's main grid. Existing supply depends mainly on 16 diesel generator sets across the Tashan, Xiaxing, and Qilin stations, with total installed capacity of about 113.3 MW and peak load around 60 MW. Diesel generation is expensive and strategically fragile because all fuel arrives by sea.

Even though Kinmen has already advanced a low-carbon island agenda and has made visible gains in solar, wind, and storage, its shallow-grid architecture makes large renewable integration significantly harder than on Taiwan's main island. The Wudao hybrid microgrid programme responds to that constraint by combining fuel diversification, flexible storage, and hydrogen reserve into one island-scale resilience design.

Participating Bodies and Roles

Hengmao leads the programme as EPC contractor and system integrator from detailed design through civil delivery, M&E installation, and microgrid control integration. National Quemoy University supports local renewable-resource modelling, power-quality observation, hydrogen-safety assessment, and island carbon-footprint analysis. National Cheng Kung University contributes the power-system dispatch algorithms and real-time simulation environment, while ITRI validates the PEM electrolyser and hydrogen fuel-cell systems. The Kinmen County Government Construction Department leads the programme with support from the Bureau of Energy, the National Development Council, Taipower, CPC, and Kinmen Kaoliang Liquor as a strategic industrial energy partner and biomass feedstock supplier.

Engineering Design and Technology Pathway

The system is organised around six linked subsystems: a 15 MW LNG satellite receiving and gas-power station, a 1.5 MW biogas plant based on Kaoliang distillery residues, livestock manure, and household food waste, major renewable-capacity expansion, a 2 MW PEM electrolysis and hydrogen-storage centre, a 15 MW / 30 MWh battery energy-storage system, and a unified microgrid EMS. The gas-power block provides stability and partial diesel replacement. The biogas block closes a local circular-economy loop through distillery residues and agricultural reuse. Expanded PV and wind raise renewable penetration, while the PEM system converts surplus renewable output into stored hydrogen as a flexible load.

Hydrogen is positioned as both resilience reserve and future transition vector. Stored hydrogen supports emergency generation for hospitals, ports, and fire services, provides blending trials into the gas-power stream, and enables pilot hydrogen transport. The storage system and dispatch layer, refreshed every few seconds through the EMS, manage charging, discharging, gas, biogas, and electrolysis output together so that frequency deviations remain tightly controlled even under islanded conditions.

Results and Impact

Full operation is targeted for 2030 after a programme investment of about NT$4.2 billion. The expected outcome is a reduction in island-wide carbon emissions from about 180,000 tonnes CO2 to roughly 95,000 tonnes, with diesel's share of generation dropping below 35 percent. Natural gas, renewables, biomass, and hydrogen together create a more diversified supply stack, while storage plus hydrogen reserve are designed to keep critical public infrastructure running for at least 72 hours even under severe fuel-shipping interruption scenarios.

The project is also expected to lower Taipower's annual Kinmen operating losses, create 85 full-time roles plus 250 construction jobs, and establish a reusable offshore-island microgrid delivery package for Matsu, Penghu, and other remote territories. In strategic terms, it turns Kinmen from a diesel-dependent frontier island into a test bed for resilient multi-vector net-zero infrastructure.