Solar Hybrid System for a Luxury Home Resort

Background

This private luxury home resort in Pattaya had a substantial electricity problem. With multiple buildings, pool systems, air conditioning, lighting, and guest facilities running around the clock, the property’s monthly electricity bill had climbed to nearly ฿100,000 — a significant and growing operating cost that the owner had little ability to control.

The homeowner’s goal was clear: achieve genuine energy independence. Not just a reduction in bills, but true 100% energy security — the ability to run the resort entirely from renewable energy, with battery backup to maintain supply through the night and on overcast days.

The Challenge

Two engineering challenges made this project more complex than a straightforward rooftop installation.

Multiple rooftop structures

The resort’s solar panels are spread across several separate rooftops — each at different orientations and heights. This required careful system design to manage long DC and AC cable runs between rooftops and the central inverter plant, minimising losses while keeping the installation clean and safe.

Integration with the existing electrical infrastructure

The property’s existing electrical system needed significant modification to support the hybrid architecture. This involved designing and installing a new Automatic Transfer Switch (ATS) cabinet connected directly to the incoming transformer, then migrating the main distribution board (MDB) cables to feed through the ATS as the primary load. This configuration gives the system full visibility and control over all loads — and allows seamless, automatic switching between solar, battery, and grid power with no interruption to supply.

The Solution

Kunini designed and installed a fully integrated solar hybrid system combining high-output PV generation, dual inverter architecture, and a large-scale battery bank — purpose-built to meet the resort’s energy independence objective.

Solar Generation — 240 kWp

381 LONGi HiMO 7 630W bifacial solar panels form the generation backbone of the system. Bifacial technology captures light from both the front and rear of each panel, increasing yield — particularly valuable across a multi-rooftop installation where reflected light from roofing surfaces contributes additional output.

Every string is fitted with AndSolar optimisers with Rapid Shutdown (RSD) enabled. The optimisers maximise production from each panel independently, eliminating the effect of partial shading between rooftops and ensuring each panel operates at its peak. RSD compliance ensures the system meets international safety standards, allowing rapid de-energisation of the rooftop in an emergency.

Panels are mounted on Antai solar racking systems, designed for Thailand’s tropical climate and wind loading requirements.

Inverter Architecture — 165 kW Total

The system runs a dual-inverter configuration, allowing the full 240 kWp of generation to be utilised effectively while maintaining stable, continuous power supply across all resort facilities:

Solis 125 kW Hybrid Inverter — manages the battery bank, prioritises solar self-consumption, and controls load distribution between solar, battery, and grid.

Solis 40 kW Grid-Tied Inverter — captures additional solar generation capacity and feeds it into the system.

Battery Storage — 522 kWh

Two Solis EverCore NV battery storage units, each with 261 kWh of usable capacity, give the system a total of 522 kWh of battery backup. This is sufficient to power the resort through the night and provide meaningful buffer on days with reduced solar generation — a critical requirement for a property where uninterrupted power supply is not optional.

Electrical Works

Kunini’s licensed electrical team designed and installed the ATS cabinet and carried out the full MDB migration, bringing the entire resort’s electrical load within the scope of the hybrid energy management system. All works were completed to Thai electrical standards with minimal disruption to resort operations.

Monitoring

The full system is monitored in real time via SolisCloud, providing live data on solar generation, battery state of charge, load consumption, and grid interaction. The resort owner can view full operating data at any time — confirming energy independence and system performance day by day.

Results

Since commissioning, the resort operates almost entirely on renewable energy. The battery bank stores excess solar generation during the day and supplies the resort through the evening and overnight hours. The grid connection remains available as a backup, but in practice draws close to zero.

The monthly electricity bill — previously approaching ฿100,000 — has fallen to near zero. On a typical clear day, the system yields over 260 kWh, charges the battery bank to full, and supplies all resort loads simultaneously, with the grid sitting at 0 kW throughout daylight hours.

The homeowner now has complete energy security: a resort running on sunlight, backed by over half a megawatt-hour of storage, with no dependence on the grid for day-to-day operation.

System Specification

Component	Specification
Hybrid Inverter	Solis 125 kW Hybrid Inverter
Grid-Tied Inverter	Solis 40 kW Grid-Tied Inverter
Battery Storage	Solis EverCore NV — 2 × 261 kWh = 522 kWh total
Solar Panels	LONGi HiMO 7 — 630W Bifacial, 381 panels
Total PV Capacity	240 kWp
Optimisers	AndSolar Optimisers with RSD
Mounting	Antai Solar Racking
Monitoring	SolisCloud
Electrical Works	ATS Cabinet, MDB Migration

Location

System Type

Solar PV Capacity

Battery Storage

Previous Monthly Bill

Monthly Bill After

Renewable Energy Share