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Grid-Parallel · Self-Use

Solar Grid-Parallel Application for Self-Use (MEA/PEA) Steps, Documents & Fees 2026

If your rooftop solar is only for self-use and you are not selling power, do you still need utility approval? Yes — connecting your system in parallel with the grid (ขนานไฟ) is about safety and standards. This page summarises the parallel-connection filing for a self-use, no-sale home: where to apply online (MEA MyEnergy / PEA PPIM DG-SELF), the steps, documents, the utility-certified inverter requirement, the zero-export rule for larger systems, and the fees you must confirm with the utility directly.

6 min readLast updated: August 2026As of: Aug 2026 — steps/fees per the utilities, call 1130/1129

Even a self-use, no-sale rooftop solar system must file “ขนานไฟ” (grid interconnection) with the utility before you switch it on. ขนานไฟ is the approval to connect your solar to the utility grid so the two operate together safely and to standard. Apply online: MEA area (Bangkok, Nonthaburi, Samut Prakan) via MyEnergy — PEA area (other provinces) via the PPIM DG-SELF path (install-for-self-use, no sale). Key conditions: the inverter must be a utility-certified model, and a system exceeding 15% of the transformer capacity must install a Zero Export Controller or Reverse Power Relay (to block reverse feed). Fees/inspection charges: confirm directly with the utility — MEA 1130 / PEA 1129. If you also want to sell the surplus, that is a different route — see the sell-back program.

What Is ขนานไฟ (Grid-Parallel) & Why File It?

ขนานไฟ means connecting your own generator (the solar) in parallel with the utility grid so both can supply power together, safely. Approval is needed even for self-use because once the inverter feeds the same circuit as the grid, it must have reverse-feed protection and must cut out when the grid drops (anti-islanding) so it does not endanger line crews or equipment — so the utility inspects and approves the standard before you switch on.
Installing on-grid solar without filing ขนานไฟ is an unauthorised connection — unsafe and grounds for disconnection. Every on-grid system, at any size, must be approved before it synchronises with the grid.

How to File Grid-Parallel With MEA / PEA (Online)

Check your bill to see which utility serves your home, then file online with that utility — for “self-use, no sale”, PEA uses the PPIM DG-SELF channel:

ItemMEAPEA
Service areaBangkok, Nonthaburi, Samut PrakanAll other provinces
Online channelMyEnergyPPIM (DG-SELF)
Hotline11301129
Approved inverter listMEA interconnection standardsmartlist.pea.co.th

The main parallel-connection flow (condensed from the utilities' charts — MEA runs it through MyEnergy):

  1. Prepare system data & pick a certified inverter

    Gather the capacity, the single-line diagram of the connection and the equipment specs. The inverter must be a utility-certified model (PEA's list is at smartlist.pea.co.th/products), and the capacity should not exceed your approved supply size.

  2. File the parallel-connection request online

    MEA: file via MyEnergy — PEA: file via PPIM DG-SELF (install-for-self-use, no sale). Pick the customer account (CA) number, complete the request form and upload the documents in its annex; use a power of attorney if the filer is not the meter owner.

  3. The utility reviews documents & local grid capacity

    The utility checks the documents, the system size against the local transformer, and the interconnection standard — a system exceeding 15% of the transformer capacity needs reverse-feed protection (see the zero-export section below). Incomplete uploads leave the request pending until completed.

  4. Site inspection & sign the interconnection agreement

    The utility inspects the installed system against what you filed and signs the interconnection agreement (electronic signature supported) once it meets the safety and protection standards.

  5. Meter set-up, then parallel operation begins

    The utility adjusts or swaps the meter to suit your usage, allows the first synchronization, and you may then run the solar in parallel with utility power as normal.

Timeframes and sub-steps differ slightly between MEA/PEA and by local inspection queues — if the filing stalls, call 1130 (MEA) / 1129 (PEA), or have an installer who routinely handles ขนานไฟ paperwork run it for you.

What Documents & Fees Does ขนานไฟ Need?

The core document list (the full detail sits in each utility's request-form annex):

The meter owner's ID card and a copy of the house registration — plus a power of attorney if someone else (e.g. the installer) files on your behalf.

System details and connection design: capacity, the single-line diagram, and the inverter/panel specs.

Proof of a utility-certified inverter and (if the system exceeds 15% of the transformer) evidence of the reverse-feed device — Zero Export / Reverse Power Relay.

Fees / connection-inspection charges: the utilities do not publish a standard household figure on their main pages, and the cost depends on system size and meter changes — confirm the exact amount before proceeding, at MEA 1130 / PEA 1129 (some installer blogs quote numbers, but those are not official announcements, so this page does not assert them).

Self-Use, No Sale — Do I Need Zero Export?

It depends on your system size versus the local transformer: under MEA's standard, a system exceeding 15% of the transformer capacity must install a Zero Export Controller or Reverse Power Relay (RPR) to stop surplus power flowing back into the grid — a natural fit for a home that intends pure self-use with no sale. For how the no-export configuration and hardware work, see the zero-export system page. The exact transformer-% threshold and settings follow your local contracting utility.

Want to Sell the Surplus Too? How It Differs

Self-use grid-parallel (this page) = permission to connect so you can use your own generation; no sell contract, no income from surplus (leftover power is either not exported or blocked from flowing back). Selling the surplus = you additionally join the Solar Phak Prachachon / sell-back program, which has a 2.20 THB/unit purchase contract, a 5 kW cap, Type-1 homes only, and a separate process/quota. For the whole legal framework of home solar see the rooftop-solar regulations page; and once connected, don't miss the home-solar tax deduction.

About the Author

Compiled by the CapSolar team under Frank Lee (Founder). CapSolar is a commercial & industrial solar EPC/PPA provider in Thailand that condenses utility paperwork and interconnection standards from primary sources so households and businesses can proceed correctly. Confirm fee figures and case-specific conditions with the utility before proceeding.

FAQ

Yes — every on-grid system, at any size, must file ขนานไฟ and be approved before switch-on, because it concerns safety and reverse-feed protection even when you are not selling. File online at MEA MyEnergy (MEA area) or PEA PPIM DG-SELF (PEA area).

Bigger Than a Home? CapSolar Handles Design to Interconnection

A home can file ขนานไฟ itself — but for a commercial building or factory, the paperwork, interconnection standard and reverse-feed protection are far more complex. CapSolar runs EPC/PPA end-to-end from design through permitting to grid connection, with a free assessment from your actual bill.