How an 80-household kampung 35 km from the grid replaced an 8-hour diesel genset with a grid-forming Huawei SUN2000 + LUNA2000 microgrid — and kept the clinic vaccine cold-chain running through the night
tCO₂ offset annually
“For thirty years this kampung ran on a diesel generator from 6 pm to 2 am. When the generator broke down, families were in darkness and the clinic could not keep vaccines cold. Now we have power 24 hours, the children study at night, and the clinic nurse can store medicine with confidence. This is the most important thing that has happened to our community in my lifetime.”
Sabah's interior districts — Pensiangan, Nabawan, Keningau, and Tenom — contain hundreds of kampung communities that remain beyond the reach of Sabah Electricity Sdn Bhd's (SESB) grid. Note that Sabah and Sarawak operate under SESB and SEB respectively, separate from Peninsular Malaysia's ATAP/NEM framework; rural electrification here falls under state and federal programmes, including the Rural Electrification Programme (REP) and, increasingly, CSR-matched renewable energy grants from the Sabah state government's JKJR (Jabatan Kemajuan Jalan Raya) and community development funds.
For this particular kampung — a community of approximately 80 households clustered around a primary school (Sekolah Kebangsaan) and a klinik desa (rural health clinic) — the electricity situation had not materially changed since 1993. A diesel generator funded originally by a federal government grant provided power from 18:00 to 02:00 on evenings when fuel was available and the engine was functioning. Generator breakdowns, which occurred several times each year, plunged the community into complete darkness. Each breakdown episode cost RM 2,000–4,000 in emergency fuel delivery and repair charges, on top of the baseline RM 8,000/month in regular diesel costs — a staggering expense for a subsistence farming community.
The consequences were measurable. UNICEF and Universiti Malaysia Sabah research on interior Sabah communities has documented that limited evening electricity directly suppresses children's study hours, with each additional hour of reliable after-dark lighting correlating with improved PMR and SPM examination outcomes. The klinik desa's vaccine cold-chain was the most critical vulnerability: the clinic operated three vaccine refrigerators on a separate small diesel unit, but repeated power interruptions caused temperature excursions that had resulted in vaccine wastage on at least two occasions — a clinical risk the district health officer had escalated formally to the state health department.
Trexon was engaged by the project sponsor — a Sabah-based CSR foundation working with the JKKK (Jawatankuasa Kemajuan dan Keselamatan Kampung) — to assess whether a solar microgrid could replace the diesel genset entirely rather than merely supplementing it.
The critical engineering question was not generation capacity but grid quality. A rural community load — fluorescent and LED lighting, ceiling fans, rice cookers, small refrigerators, TV sets, the clinic's vaccine refrigerators and medical equipment — has a highly variable and bursty demand profile. Household fridges cycling on and off, induction cookers starting simultaneously at meal-times, and the clinic's centrifuge spinning up during medical procedures all introduce voltage transients that simple off-grid inverters handle poorly, causing flicker complaints and equipment damage.
Trexon's engineering assessment concluded that a standard off-grid string inverter arrangement would require extensive load management and would still produce unacceptable voltage quality for the clinic's medical equipment. The recommended solution was the Huawei SUN2000-150K-MG0 with its native grid-forming control capability — a microgrid controller that synthesises a stable 400V/50Hz grid reference from the battery bus, maintaining voltage and frequency within IEC 61727 limits regardless of load variation.
Solar Array: 240 × Trina Vertex S+ 500W Bifacial
240 units of Trina Solar Vertex S+ 500W bifacial panels were mounted on ground-mounted galvanised steel structures installed on cleared community land adjacent to the school. Ground mounting was chosen over rooftop installation for three reasons: structural condition of existing buildings was unknown and varied across the community; community-owned land was available; and ground-mounted arrays are easier for local community members to inspect and maintain with basic training.
The bifacial panels were selected for their ability to harvest reflected irradiance from the cleared grass ground surface — a 5–8% yield uplift versus monofacial alternatives, meaningful in an off-grid context where every kWh reduces diesel backup dependency. Total installed DC capacity: 120 kWp.
Microgrid Controller: Huawei SUN2000-150K-MG0
The SUN2000-150K-MG0 operates as the community's virtual grid reference. Its grid-forming control algorithm — developed from Huawei's experience deploying microgrids in remote Chinese villages and high-altitude BESS projects — maintains a stable island grid regardless of whether generation is predominantly from PV (daytime), battery (evening and night), or a hybrid of both during transitional hours. The controller's blackstart capability allows the system to restart from a fully discharged battery state using PV generation alone — critical for a community 35 km from the nearest grid connection point.
Battery Storage: Huawei LUNA2000-215 (200 kWh)
Two LUNA2000-215 battery units (approximately 200 kWh total usable capacity at 90% depth of discharge) were installed in a purpose-built battery house — a ventilated concrete block structure constructed by the community's own labour under Trexon's supervision. The battery house location was selected to minimise cable run length from the inverter and to provide shade, reducing ambient temperature and extending battery cycle life.
At the community's average evening and night load of approximately 25–35 kW, 200 kWh of storage provides 6–8 hours of full island operation with no solar input — ensuring reliable power through the entire night even on days of low irradiance.
Distribution: New LV Network
The existing diesel genset distribution network was a partially improvised arrangement of overhead conductors with inconsistent cable sizing and no proper earthing. Trexon's electrical team installed a new low-voltage distribution board in the battery house, with dedicated circuits for the school, the klinik desa (fitted with a preferential load circuit to protect clinic equipment during low-battery conditions), and the residential distribution network. Proper earth leakage protection (ELCB) was installed on all circuits — a safety upgrade that the original diesel system had never provided.
The klinik desa vaccine cold-chain was designated as a Priority Load — the LUNA2000 battery management system is programmed to protect this circuit even if the battery falls below 20% state of charge, shedding non-critical household lighting loads before curtailing clinic power. The three vaccine refrigerators (combined load: approximately 900 W continuous) operate in a separate circuit with an uninterruptible 24-hour supply guarantee.
During commissioning, Trexon's clinical engineering partner verified that all three vaccine refrigerators maintained continuous 2–8°C throughout a simulated 72-hour worst-case test (overcast sky scenario with minimum generation). The district health officer, present at commissioning, confirmed that this was the first time in his 12-year posting that the Pensiangan district clinics had achieved a certified continuous cold-chain baseline.
Construction of the solar arrays and battery house took 14 working days, with a team of eight Trexon engineers and four trained electrical technicians from Kota Kinabalu. Community members participated in ground clearing, concrete works, and fence construction — both to reduce project cost and to build local ownership and familiarity with the installation.
Post-installation, Trexon conducted a one-day community training session for six volunteer system monitors selected by the JKKK. Training covered: daily system status check via the Huawei SmartLogger display; recognition of fault indicators; basic cleaning of panel surfaces; and the emergency contact protocol for remote monitoring support from Trexon's KL operations team, which monitors the system's SmartLogger data feed via the Huawei FusionSolar platform.
Power availability:
The community has had 24-hour electricity for every day since commissioning — the first time in the kampung's recorded history. System availability over six months: 99.2% (three events totalling 14 hours of reduced-capacity operation due to a cloudy-weather battery depletion in March, a lesson incorporated into the dry-season pre-charge protocol).
Child study hours:
A baseline survey conducted by the project sponsor in December 2025 found that children in the kampung averaged 1.1 hours of self-directed study after school each weekday, limited by the diesel generator's 18:00 start time. A follow-up survey in June 2026 found average after-school study time had increased to 2.8 hours — a 60% increase, attributed directly to afternoon and evening lighting availability.
Vaccine cold-chain:
Zero cold-chain temperature excursions recorded in six months. The district health officer confirmed this is the first six-month period without a cold-chain incident at this clinic since records began in 2014.
Diesel cost elimination:
The community's JKKK fuel ledger shows RM 0 diesel expenditure since commissioning — a saving of RM 8,000/month relative to the 2025 average. The CSR grant is being partially repaid through a community fund that retains 30% of the former diesel cost as a maintenance reserve for battery replacement at year 8–10.
Environmental:
The system displaces approximately 265 tonnes of CO₂ equivalent per year — removing the environmental impact of 38,000 litres of diesel combustion annually.
There are an estimated 800–1,200 communities in Sabah and Sarawak still relying on diesel gensets or without reliable electricity access. The economics of diesel in remote interiors — where delivery costs multiply the pump price by 2–4× — make solar microgrids financially competitive with continued diesel operation in as few as 5–7 years, even before accounting for fuel supply reliability risk. The Huawei SUN2000-150K-MG0 grid-forming platform, combined with LUNA2000 storage, represents a generation of microgrid technology that can deliver utility-grade power quality to communities of 50–500 households without connecting to the national grid.
Note: Financial figures represent indicative modelling based on Trexon project data and local diesel fuel costs. Community details are shared with JKKK permission.
Get a free consultation and see how much you can save with solar.