Short answer
The connection approval letter (çağrı mektubu) is the official letter by which the grid operator, AEDAŞ in Antalya, confirms a positive connection opinion on your unlicensed solar application. The letter starts project approval and connection agreement steps and becomes void if the period passes. Facilities that receive a letter after 12.05.2019 are subject to 2026 rules such as hourly net metering and the double ceiling.
Key takeaways
- For a complete application up to 25 kW, the letter is issued within the first 20 days of the following month.
- A connection opinion is given directly for facilities with a contract power of up to 3 kW.
- After the letter there are 90 days for project approval (25 kW procedure); the 14.05.2024 amendment provides 1 year in the general provision, so rely on the period in your letter.
- For facilities with a letter dated after 12.05.2019, the annual generation ceiling is twice consumption (Art. 26/17).
- For a system operated before acceptance, the connection is cut and a 3-year application ban applies.
The connection approval letter (çağrı mektubu) is the document showing that the grid operator has given a positive connection opinion on your unlicensed solar application and is inviting you to proceed with project approval and connection procedures. In Antalya, this letter is issued by AEDAŞ (the local electricity distribution company). Without a connection approval letter you cannot move on to project approval or grid connection; moreover, facilities that receive a connection approval letter after 12.05.2019 are subject to different sections of the 2026 rules. This article is based on information verified as of October 2026.
What is a connection approval letter (çağrı mektubu) and who issues it?
The connection approval letter is the first official approval of an unlicensed generation application. If the documents in your application are complete, the grid operator (AEDAŞ in Antalya) forms a positive connection opinion for the facility to be connected to your consumption point and notifies you of it with the connection approval letter. At this stage you are not yet authorized to build the system or connect it to the grid; the letter gives you the right to apply for the next step, project approval.
The letter comes not from EPDK (Turkey's Energy Market Regulatory Authority) but from the relevant grid operator. AEDAŞ has accepted applications only through the LUS platform since 01.10.2023. We described how to apply step by step in our article on how to apply for a rooftop solar plant.
The difference between the letter and the connection opinion
The two concepts are close but not the same. A connection opinion is a technical assessment stating that the grid is suitable for connecting that power at the applied point. The connection approval letter is the official document by which this positive assessment is communicated to the applicant. According to the EPDK Procedures and Principles, for systems up to 25 kW, a connection opinion is given directly for facilities with a contract power of up to 3 kW. For other facilities, a positive connection opinion is formed for a complete application within the first 20 days of the following month and the letter is issued.
The process and timelines after the letter
The letter is a beginning; steps with deadlines follow it. The table below summarizes the timelines in the EPDK Procedures and Principles (consolidated text, last amended 12.03.2022) for rooftop systems up to 25 kW.
| Stage | Timeline | Note |
|---|---|---|
| Issuing the letter | First 20 days of the following month | Provided the application is complete |
| Announcement of results | Last 10 days of the month | On the company's website |
| Mailing the letter | Within 7 days | To the applicant |
| Applying for project approval | 90 days from notification | An additional 90 days if needed |
| Connection agreement | 15 days after project approval | Signature |
| Acceptance | 1 year from the agreement | Otherwise the agreement becomes void |
| System usage agreement | 3 days after the acceptance application | The assessment of surplus energy begins |
A warning is needed on timelines. The consolidated text of the 25 kW procedure provides 90 days for project approval. The 14.05.2024 amendment of the regulation, however, grants 1 year for project approval after the letter. Apply whichever period is valid for your file; the safest course is to rely on the period written in your connection approval letter and, if in doubt, to ask AEDAŞ for written confirmation. If the period passes, the letter becomes void and you may have to apply again.
What information should you check in the letter?
A template letter is attached to the Procedures and Principles. According to the template, a bidirectional hourly meter at the connection point and a separate control meter measuring production are used. In the letter sent to you, check the facility capacity, the connection point and the periods given. If the capacity or consumption point information is wrong, the error should be reported to the grid operator before it creates a problem at the project approval stage.
Why is the connection approval letter important?
The date of the letter is not just a formality; it determines which rules will apply. The Unlicensed Electricity Generation Regulation has special provisions for facilities that receive a connection approval letter after 12.05.2019.
- Hourly net metering: From 1 May 2026, generation and consumption are netted separately for each hour in renewable facilities (non-residential) with a post-2019 connection approval letter. For residential use, net metering is monthly.
- Annual generation ceiling: The annual generation of these facilities cannot exceed twice the annual consumption of the associated consumption facilities (Art. 26/17).
- Contract power floor: The total contract power of the associated consumption facilities cannot be lower than the installed capacity; if the condition is not met, generation is counted as an unpaid contribution to YEKDEM (Art. 28/5-6).
For this reason, the date of the letter affects which net metering and limit regime your facility falls under. We summarized the general framework of the legislation in our article on the unlicensed electricity generation regulation, and the treatment of surplus energy in our article on selling surplus electricity.
Points to watch when receiving the letter and afterwards
Your documents must be complete
The letter is given only to a complete application. For systems up to 25 kW, the application form (Annex 4), ID, a title deed or lease, the unique code and a declaration of no prohibition on activity (Annex 2) are required; in apartment buildings and housing complexes, a notarized copy of the minutes book decision is also requested. Preparing the documents from the start is critical for being evaluated within the first 20 days of the month. You can find the document list in the article on documents required for solar plant installation.
Time the equipment purchase
Main equipment such as panels, inverters and batteries must have been manufactured within the last five years (Art. 37/6). This is an interpretation: buying major equipment before the letter and project approval arrive carries timing and approval risk. Waiting first for the letter and project approval and then planning the equipment order may be safer.
Do not run the system before acceptance
Receiving the letter is not permission to run the system. The connection of a facility operated before acceptance is cut, the equipment must be removed within 60 days and the owner cannot apply for 3 years (Official Gazette 14.05.2024).
Transfer and facility changes
According to the 25.11.2025 amendment, if the generation facility is transferred, a new application for the associated consumption facility is restricted; inheritance and bankruptcy are outside this restriction. If you are planning a change of ownership, assess this rule in advance.
Common mistakes in the connection approval letter process
- Applying with a missing document; this can cause you to miss the next month's evaluation.
- Not marking the period on the letter in your calendar and being late for project approval.
- Choosing a system capacity above the contract power; under the simple procedure, the facility cannot exceed the contract power.
- Commissioning the system before acceptance is completed.
- In apartment buildings, skipping the minutes book decision and the notarized copy.
Remember that other institutions may also ask for this letter as a document. For example, the KOSGEB (Turkey's small and medium enterprise agency) Green Industry Support Program's 2023-01 rooftop solar call required a valid letter; however, that call's application window closed in November 2024 and no new open call has been verified. The support is repayable, not a grant. Banks may also request the project's official documents in a credit assessment; because conditions are set by project, we do not give definite information.
The letter process in Antalya and Solar Nexo support
AEDAŞ publishes its preliminary evaluation and technical evaluation committee decisions every month; the most recent decision seen on the access date belonged to August 2026. You can follow the result of your application from these decisions and the LUS platform. Because there is no official figure for the actual time from application to grid connection, we make no promise of a timetable.
In Antalya, different subscriber profiles require different preparation. In holiday homes in Manavgat, Alanya and Kemer, consumption can be seasonal; in that case system capacity should be chosen according to real consumption and contract power. For hotels and businesses, even though contract power is high, the subscriber group and hourly net metering rules are assessed separately. For agricultural irrigation wells in Korkuteli and Elmalı, the double-contract-power rule and the 2026 contract power floor calculations come into play. In every profile, the date and content of the letter directly affect the later net metering arrangement.
On Solar Nexo's website, the steps Connection Approval Letter (çağrı mektubu) Application and Project Approval and Installation are defined for net metering systems. The team checks consumption and contract power at the survey and prepares the application. For details of net metering systems, see the net metering systems page.
Every step of the process should be recorded. Note the application date, the file number on LUS, the notification date of the letter and the last day given for project approval somewhere. Keeping the correspondence you receive makes things easier in case of an objection or a request for an extension. In a doubtful situation, applying in writing to the grid operator is safer than relying on verbal information.
Conclusion
The connection approval letter is the gateway to the unlicensed solar process: it communicates the positive connection opinion, starts the period for project approval and sets the date that determines the rules the facility will be subject to. Not missing deadlines, preparing documents completely and not running the system before acceptance are the basic rules. If you would like to plan your application together, you can request a free site survey.
Frequently asked questions
What is a connection approval letter (çağrı mektubu)?
The connection approval letter is the official letter stating that the grid operator has given a positive connection opinion on your unlicensed electricity generation application. In Antalya, AEDAŞ issues this letter. The letter gives the right to apply for project approval; it is not permission to build the system or connect it to the grid. If the period passes, the letter becomes void. It is also an important date marker that determines the rules the facility will be subject to.
How long does it take for the connection approval letter to be issued?
According to the EPDK Procedures and Principles, for systems up to 25 kW a positive connection opinion is formed for a complete application within the first 20 days of the following month and the letter is issued. Results are announced on the company website within the last 10 days of the month, and the letter is mailed within 7 days. For facilities with a contract power of up to 3 kW, a connection opinion is given directly.
How many days are there for project approval after the connection approval letter?
For rooftop systems up to 25 kW, the consolidated Procedures and Principles provide 90 days from notification, with an additional 90 days if needed. The 14.05.2024 amendment of the regulation grants 1 year in the general provision. You should confirm from your letter and from AEDAŞ which one applies to your file.
What happens if the connection approval letter's period passes?
If project approval is not applied for within the period, the letter becomes void and you may have to apply again. For this reason it is important to mark the period on the letter in your calendar. After the connection agreement, acceptance must also be completed within 1 year; otherwise the agreement becomes void. So mark all the deadlines in your calendar and, if necessary, ask the grid operator for written confirmation.
Can a system be installed without a connection approval letter?
Without the connection approval letter, project approval and the connection agreement, it is not possible to connect the system to the grid or run it. The connection of a facility operated before acceptance is cut, the equipment must be removed within 60 days and the owner cannot apply for 3 years. Equipment purchases should also be planned in step with the process, bearing in mind the condition that main equipment must have been manufactured within the last five years.
Why is the date of the connection approval letter important?
For renewable unlicensed facilities that receive a letter after 12.05.2019, there are special provisions such as the annual generation ceiling (twice consumption), hourly net metering (non-residential, from 1 May 2026) and the contract power floor. For this reason, the date of the letter determines the rules the facility will be subject to. Confirm current practice with the grid operator.
Does Solar Nexo make the connection approval letter application?
On Solar Nexo's website, the steps Connection Approval Letter (çağrı mektubu) Application and Project Approval and Installation appear for net metering systems. The process starts with a free site survey; the team supports document preparation and follow-up. The applicant needs to have their own documents, such as ID and a title deed or lease, ready and, in apartment buildings, have a copy of the minutes book decision notarized.
Sources
Want a clear calculation for your roof?
The Solar Nexo team carries out a free site survey at your address in Antalya and designs the system that suits your roof, consumption and budget.
