Oriental Plaza Condo 66.96kWp Solar — Pattaya

Project Overview

Oriental Plaza Condo is a residential condominium located in Pattaya, Chonburi — a high-rise property with significant shared-area electricity consumption across common facilities, lifts, corridor lighting, car park ventilation, and pool equipment. With electricity costs representing one of the largest recurring operating expenses for the juristic person, the condo management engaged Kunini Solar EPC to design and install a rooftop solar system sized to the maximum capacity the available roof space would allow.

The resulting 66.96kWp DC system — commissioned in May 2025 — is configured exclusively for self-consumption, with zero export to the grid. Every kilowatt-hour generated by the panels is consumed directly within the building, reducing the amount of electricity drawn from PEA at full retail tariff rates and delivering an immediate, measurable monthly saving to the condominium.

The Challenge

The available roof area at Oriental Plaza Condo was split across two surface types — a flat concrete roof section and a pitched metal sheet roof — each requiring a different mounting approach. Maximising the usable area across both surfaces, while staying within structural load limits and PEA interconnection rules, required careful system layout planning.

As a residential building drawing power on a standard low-voltage tariff, there is no facility for grid export — meaning the system had to be precisely sized and controlled to avoid feeding surplus energy back into the PEA network. This required the installation of a zero-export control system using current transformers (CTs) at the main MDB panel, with real-time power limiting managed by the inverters.

Additionally, with 108 panels spread across a mixed roofline, individual panel shading and safety were priorities — particularly for the metal sheet sections where partial shading from roof features could reduce output and where module-level rapid shutdown (RSD) is essential for safe servicing.

The Kunini Solution

Kunini designed a 66.96kWp DC / 66kW AC system using 108 LONGi LR7-72HTH 620W Bifacial solar panels — a high-efficiency monocrystalline PERC bifacial module that captures light from both the front and rear surfaces, improving yield particularly on the flat concrete roof where reflected albedo is available from the light-coloured surface.

A Huawei Solar Optimizer was installed on each of the 108 panels. Optimizers perform module-level maximum power point tracking (MPPT), ensuring that shading or soiling on any individual panel does not drag down the output of the entire string. Each optimizer also acts as a Rapid Shutdown Device (RSD), cutting DC voltage at the panel level within seconds when the inverter is powered down — a critical safety feature for roof maintenance and emergency response, and a requirement under modern PEA installation standards.

Two Huawei grid-tied string inverters were selected — a 36kW unit and a 30kW unit — creating a combined AC output of 66kW. Splitting the system across two inverters improves overall system resilience: if one unit requires servicing, the other continues generating, and the load balancing allows each inverter to operate closer to its rated efficiency point.

Zero-export control was configured using CTs installed at the main MDB panel. The inverters monitor real-time load and automatically modulate output to match consumption — ensuring that at no point does generated power exceed the building’s demand and flow out to the PEA grid. The system was installed and commissioned in full accordance with PEA regulations.

The Result

The Oriental Plaza system generates approximately 280 kWh per day and around 8,600 kWh per month — with 100% of that generation consumed on-site. At current PEA residential tariff rates, this translates to a monthly electricity cost saving of approximately THB 50,000 for the condominium’s juristic person.

On an annual basis, the system is expected to offset approximately 103,000 kWh of grid electricity — equivalent to avoiding around 60 tonnes of CO₂ emissions per year, based on Thailand’s current grid emission factor. This is comparable to planting approximately 3,000 trees annually, and represents a meaningful contribution to the building’s environmental footprint reduction.

The live monitoring dashboard — accessible via Huawei FusionSolar — gives the building management real-time visibility into generation, consumption, and grid import data, and provides historical performance reports for transparency with residents and owners.

“I would like to thank Daniel and his team for their professional and efficient installation of our solar power system. From the first point of contact, Daniel was only too happy to provide all the necessary information to enable an understanding of solar power systems, constraints and benefits, along with any other questions about the installation. During the installation process, any challenges or problems were carefully considered, discussed and resolved in a professional manner, and to everyone’s satisfaction. Overall, the project was installed in an efficient and quality manner, resulting in the project being completed quicker than what was anticipated. I would recommend Kunini for your solar power system installation.”

- David, Oriental Plaza Condo, Pattaya · ★★★★★ Google Review, July 2025

System Highlights

108 × LONGi LR7-72HTH 620W Bifacial panels — front and rear generation for improved flat-roof yield
Huawei Solar Optimizer on every panel — module-level MPPT and Rapid Shutdown Device (RSD) on each module
Dual Huawei inverters (36kW + 30kW) — improved resilience and efficiency across mixed roof sections
Zero-export control via CT sensors at main MDB — 100% self-consumption, PEA compliant
Mixed mounting across flat concrete and metal sheet roof — maximising every available square metre
Live monitoring via Huawei FusionSolar — real-time generation, consumption, and grid import data
~60 tonnes CO₂ avoided per year — equivalent to ~3,000 trees planted annually

Solar for Your Condominium or
Commercial Building?

If your building’s monthly electricity bill exceeds THB 30,000 and you have suitable roof space, Kunini can carry out a no-cost site assessment and provide a detailed savings proposal. Whether you’re looking at a direct purchase EPC contract or exploring a Private PPA with zero upfront investment, we’ll design a system around your building’s actual consumption profile.

Hua Hin: +66 (0) 61 413 4850

Pattaya / Si Racha: +66 (0) 82 056 7906

Email: info@kunini.com

Web: www.kunini.com