Solar Rooftop Systems for Homes and Businesses in Thailand

Solar Rooftop Systems for Homes and Businesses in Thailand

On-Grid and Hybrid Solar Solutions Designed, Installed, and Maintained by Kunini

A solar rooftop system is one of the most financially sound investments a homeowner or business owner in Thailand can make. With commercial electricity rates between 4.18 and 5.50 THB per kWh — and residential rates subject to the same quarterly fuel adjustment charges — the cost of grid electricity is a recurring expense that trends in one direction. Solar changes that.

Kunini has been designing and installing solar rooftop systems in Thailand since 2010, when we completed the first solar rooftop in Hua Hin. Today, we install on-grid and hybrid solar systems for homes, hotels, factories, retail units, and commercial properties of every size — across Hua Hin, Pattaya, Bangkok, and nationwide.

There are two primary solar rooftop system types. Understanding the difference between them is the starting point for any good solar decision.

On-Grid Solar Systems

What Is an On-Grid Solar System?

An on-grid solar system — sometimes called a grid-tied system — connects your solar panels directly to the PEA or MEA electricity grid. It generates electricity during daylight hours, powers your home or business in real time, and uses the grid as a buffer when generation exceeds or falls below your demand. There are no batteries in a standard on-grid system, keeping costs down and making it the fastest route to meaningful electricity savings.

How It Works

Solar panels mounted on your roof convert sunlight into direct current (DC) electricity. That DC current passes through a solar inverter, which converts it into alternating current (AC) — the standard form of electricity used in your home or business. The AC electricity feeds directly into your property’s electrical system and is consumed in real time.

During peak solar hours — typically 8am to 4pm — your system can significantly reduce or eliminate your grid consumption entirely. Outside of those hours, you draw from the grid as normal.

Important — Zero Export Policy: In Thailand, on-grid solar systems operate under a Zero Export policy by default. Your system is configured to consume all solar generation within your property. Surplus electricity cannot be fed back to the grid unless you have been formally approved for the PEA or MEA Feed-in Tariff (FiT) programme. Kunini can manage your FiT application — see our dedicated Feed-in Tariff page for full details.

Who On-Grid Solar Suits

On-grid solar is the right solution if:

  • You have consistent, meaningful electricity consumption during daylight hours
  • You want the shortest payback period and clearest return on investment
  • You do not require power during grid outages
  • You want maximum system size for your investment without the added cost of batteries

On-grid systems are particularly well suited to factories, retail businesses, hotels, offices, schools, and homes actively consuming electricity throughout the day.

Professional Rooftop Solar Installation

System Sizes and Indicative Savings

Solar systems are sized to match your specific consumption profile and available roof space. The figures below are indicative examples based on real-world installations at approximately 22 THB per watt installed. Your Kunini proposal will include detailed financial modelling specific to your site.

Small Retail Business — 7 days per week, 8am to 8pm, average monthly electricity bill of THB 45,000.

Suggested System Size50 kWp
Estimated System CostTHB 1,100,000
Monthly SavingsTHB 25,000
Annual SavingsTHB 300,000
Estimated ROI3.5–4 years

Commercial Hotel — 7 days per week, continuous daytime demand, average monthly electricity bill of THB 200,000.

Suggested System Size160 kWp
Estimated System CostTHB 3,520,000
Monthly SavingsTHB 80,000
Annual SavingsTHB 960,000
Estimated ROI3.5 years

Costs and savings depend on system size, site conditions, roof type, consumption profile, and current electricity tariff. All figures are pre-VAT and subject to site survey.

On-Grid System Components

Kunini selects equipment based on quality, long-term reliability, local serviceability, and compatibility with Thailand’s PEA and MEA grid requirements.

Solar Panels

We work with high-efficiency monocrystalline panels from LONGi, Aiko, and Jinko Solar — all backed by a 30-year linear performance warranty. Panel selection depends on available roof space, orientation, and target output.

Solar Inverters

We specify inverters from Huawei, Solis, and SigEnergy — all on the PEA and MEA approved inverter lists and carrying strong local support in Thailand. Inverter selection depends on system size, phase configuration, and site requirements.

Mounting Structures

We use mounting systems from Antai and RRacks, engineered for the load conditions and roof types common in Thailand — including concrete tile, metal sheet, and flat concrete rooftops.

Solar Optimisers with Rapid Shutdown (RSD)

For systems where panel-level performance and enhanced safety are priorities, we specify devices from Fonrich and AndSolar. These connect to individual panels and perform two functions: they optimise each panel’s output independently — so shading or soiling on one panel does not drag down the entire string — and they provide Rapid Shutdown (RSD) capability, dropping roof-level DC voltage to a safe level within seconds in the event of a fire or emergency. For larger commercial installations and any system where roof access is a regular requirement, RSD-capable optimisers are a meaningful upgrade.

Hybrid Solar Systems with
Battery Storage

What Is a Hybrid Solar System?

A hybrid solar system combines solar panel generation with battery energy storage, managed by a hybrid inverter that coordinates the flow of energy between your panels, your batteries, and the grid. During daylight hours, your solar panels power your property and charge the batteries simultaneously. In the evening — or during a grid outage — your property draws from stored battery energy rather than the grid.

How It Works — and the Zero Export Principle

As with on-grid systems, hybrid solar systems in Thailand are configured under Zero Export by default. All solar generation is consumed within your property first — powering your loads directly and charging your batteries. The grid is used only when solar generation and battery storage are both insufficient to meet demand. Export to the grid is not permitted without formal PEA or MEA Feed-in Tariff approval.

A well-designed hybrid system is sized to self-consume virtually all of its generation — surplus daytime energy that would otherwise be lost is stored in batteries for use in the evening or overnight.

Who Hybrid Solar Suits

Hybrid solar is the right solution if:

  • Your property has significant electricity consumption in the evening or outside peak solar hours
  • You want protection against grid outages and power interruptions
  • You want to maximise self-consumption and reduce grid dependency to the lowest possible level
  • You are planning to add EV charging powered from stored solar energy
  • You are in an area with an unreliable grid supply

Hybrid systems are particularly well suited to homeowners with evening loads, hotels and resorts operating 24 hours, healthcare facilities, and any business where power continuity is critical.

Hybrid System Components

Solar Panels

The same panel range as on-grid systems: LONGi, Aiko, and Jinko Solar, all with 30-year linear performance warranties.

Hybrid Inverters

We work with the following inverter solutions, selected to match each project’s specific requirements:

  • Solis and SigEnergy — true hybrid inverters with dedicated DC battery ports, handling solar generation, battery charging, and grid interaction in a single integrated unit. Our primary specification for full hybrid functionality.
  • Alpha ESS — an integrated hybrid energy storage solution combining inverter and battery management in one system, well suited to both residential and commercial applications.
  • Huawei — Huawei’s SUN2000 inverter range is battery-ready rather than a true hybrid architecture. It operates as a high-performance on-grid inverter compatible with Huawei’s LUNA2000 battery system, managed via a separate battery management unit. An excellent solution for clients starting on-grid and adding battery storage later, or where Huawei’s monitoring ecosystem is preferred.

Solar Optimisers with Rapid Shutdown (RSD)

Fonrich and AndSolar optimisers can be specified for hybrid installations where panel-level optimisation and rapid shutdown capability are required — same specification and benefits as on-grid systems above.

Battery Storage Systems

We specify batteries from Solis (HV and LV models), Huawei (LUNA2000), SigEnergy, and Alpha ESS. All systems use lithium iron phosphate (LFP) chemistry, delivering superior cycle life, thermal stability, and safety. Our specified batteries are rated for 6,000 to 10,000 charge cycles — equating to 15 to 25 years of useful life under normal operating conditions.

Battery capacity is specified in kWh and sized to match your evening and overnight demand. A 10 kWh battery bank can power a typical home’s evening load for three to five hours; commercial properties typically require larger banks of 30 kWh or more.

On-Grid vs Hybrid:
Which Is Right for You?

On-GridHybrid
Upfront CostLowerHigher (battery adds cost)
Payback PeriodTypically 3.5–4 yearsTypically 5–7 years
Evening / Night SavingsNoYes — draw from batteries
Grid Outage ProtectionNoYes — with sufficient battery
Self-Consumption RateGoodExcellent
Grid ExportNot permitted without FiT approvalNot permitted without FiT approval
Best ForDaytime-heavy loads, clear ROI focusEvening loads, resilience, maximum independence
Future Battery UpgradePossible with battery-ready invertersBattery included from day one

Not sure which is right for your property? Our engineers will assess your consumption profile and recommend the system that delivers the best outcome for your specific situation — free of charge.

How We Install Your System

Step 1

Free Consultation

We review your electricity bills, discuss your goals, and identify whether on-grid or hybrid solar is the better fit. No obligation, no pressure.

Step 2

Solar Survey

A Kunini engineer visits your property to assess your roof structure, orientation, available space, shading, switchgear room, and grid connection. This gives us everything we need to design a system that works for your specific site.

Step 3

Proposal and Financial Modelling

We produce a detailed proposal covering system design, equipment specification, projected savings, return on investment, contract options, and timeline. You see all the numbers before committing to anything.

Step 4

Installation

Kunini's installation teams handle the full scope of work — panel mounting, inverter installation, AC and DC cabling, switchgear connections, optimiser and RSD wiring where specified, and all safety and compliance checks. Small residential systems are typically completed in one to two days. Larger commercial systems are planned in stages to minimise operational disruption.

Step 5

Permits, Commissioning, and Grid Connection

Kunini manages all permit applications, ERC compliance documentation, and utility approvals required for your installation — whether PEA or MEA, residential or commercial. You do not need to deal with government offices or utility paperwork. Once all permits are in place, the system is fully tested and commissioned to PEA or MEA standards, including Zero Export compliance verification.

Step 6

Handover and Monitoring Setup

We walk you through your monitoring platform, confirm all warranties and service contacts, and ensure your system is performing to specification from day one. From this point, your system is live and saving.

Warranties and Ongoing Maintenance

A solar rooftop is a long-term asset. Kunini specifies equipment with strong manufacturer warranties and selects suppliers with a proven local support presence in Thailand.

Solar Panels — 30-Year Performance Warranty

LONGi, Aiko, and Jinko Solar all back their panels with a 30-year linear performance warranty, guaranteeing output does not fall below a specified percentage of rated capacity over the full warranty period.

Inverters — 5 to 10-Year Warranty

Huawei, Solis, SigEnergy, and Alpha ESS all carry standard manufacturer warranties of 5 to 10 years, with extended warranties available. All have local representation and stock in Thailand, so warranty claims are handled without international shipping delays.

Batteries — 10-Year or Cycle-Based Warranty

Battery systems carry a 10-year manufacturer warranty or a specified cycle count — whichever is reached first. With LFP batteries rated at 6,000 to 10,000 cycles, this warranty covers the full productive life of the battery under normal operating conditions.

Kunini O&M Programme

Ongoing operations and maintenance are critical to long-term system performance. Kunini offers structured O&M packages covering scheduled panel cleaning, full system inspections, inverter and battery health checks, and continuous remote monitoring. Our Customer Service team coordinates all maintenance visits and responds to any performance alerts. Cleaning frequency is adjusted based on site conditions — properties near highways, industrial areas, or construction sites may require more frequent servicing.

Ownership and Finance Options

Self-Financed Purchase

You invest upfront, own the system outright from day one, and capture 100% of the savings from the moment it goes live. Typical returns of 3.5 to 4 years for on-grid systems make this the highest long-term value option for those with available capital.

Instalment Finance

For businesses and homeowners who prefer to spread the cost, Kunini works with financing partners to provide solar hire-purchase arrangements. A down payment of typically 10 to 20% is required, with the balance paid in monthly instalments over 6 to 7 years.

Zero-Capital Options

For businesses looking for zero upfront investment, Kunini offers Private PPA contracts and Solar Energy as a Service (EaaS) agreements — both allowing you to benefit from solar without any capital outlay. See our dedicated pages for full details.

Why Kunini

Kunini has been installing solar systems in Thailand since 2010 — longer than almost any other solar EPC in the country. We installed the first solar rooftop in Hua Hin and have since completed hundreds of residential and commercial installations across Hua Hin, Pattaya, Bangkok, and nationwide.

Every project is engineered, commissioned, and maintained by our own in-house teams. Where additional labour is required on larger installations, we work with approved contractors under the direct supervision of a Kunini engineer. All commissioning, operations, servicing, and maintenance remain entirely within Kunini. You are always dealing with us, not a subcontractor.

Kunini manages every permit, ERC compliance document, and utility approval required for your installation from start to finish. Whether you are connecting to the PEA or MEA, residential or commercial — you do not need to deal with government offices or paperwork. We handle it all, so you can focus on your business.

We choose our equipment suppliers based on quality, long-term reliability, and their ability to support systems in Thailand across the full life of the installation. The brands we specify — LONGi, Aiko, Jinko Solar, Huawei, Solis, SigEnergy, Alpha ESS, Fonrich, AndSolar, Antai, RRacks — are chosen because they perform, because they are supported locally, and because our customers deserve equipment that will still be working — and still be warranted — in twenty years.

Start with a Free Solar Consultation

Whether you’re looking at your first solar system or replacing an existing one, the first step is a conversation. Kunini offers a free, no-obligation consultation and site survey — and we’ll give you a straight, honest assessment of what solar can deliver for your property.