You are using an outdated browser and your browsing experience will not be optimal. Please update to the latest version of Microsoft Edge, Google Chrome or Mozilla Firefox. Install Microsoft Edge

July 7, 2023

Cambodia Issues Environmental Code and Guidelines Benefiting Rooftop Solar Projects

Cambodia has the potential to be one of the top countries in the world for generating renewable energy through solar, based on the average amount of sunlight hours available per day and the consistent sunshine throughout the year.

The Cambodian government has recognized this potential and has made major updates to its energy policies in recent years. Solar power is now taking over a much larger portion of the total energy mix in Cambodia, especially as a number of utility-scale solar power plants have come online in recent years.

The long-term Power Development Master Plan 2022–2040 sets out the long-term energy policy for Cambodia and requires a bigger role for renewables. The use of solar power will play a key role in this aim to increase the role of renewables, with the plan foreseeing almost 30% of all national power generated through solar technologies by 2040.

Two of the latest legislative and regulatory steps by the government are the Ministry of Mines and Energy’s guidelines for rooftop solar systems, and most recently the long-awaited Environment and Natural Resources Code, which was enacted on June 29, 2023.

Rooftop Solar Projects

Many companies, from small startups to multinationals, are exploring the potential for rooftop solar in Cambodia. However, despite the favorable natural factors, the regulatory framework was not always clear or friendly to rooftop solar, hampering investment.

This started slowly changing with the adoption of the first solar energy regulation in 2018, which provided the country’s first official guidance on both solar power plants and rooftop solar. It provided some much-needed clarity, but the 2018 solar energy regulation—and especially the subsequent electricity tariff schemes—often kept rooftop projects from being financially viable.

Many players in the industry voiced their doubts about the regulations and tariffs, focusing especially on the capacity charge—a monthly electricity charge based on the total capacity of the rooftop solar project, not on consumption. Another point of contention was capacity restrictions, which limit projects in scale and therefore in profitability.

The restrictions and the capacity charge made rooftop solar much less competitive when compared to other energy sources. In many cases, rooftop solar would make the price of electricity even more expensive than purchasing it from the national grid without having rooftop solar. These factors put a serious damper on investment into rooftop solar in Cambodia.

The 2023 Solar Guidelines and the Environmental Code

Noticing the lack of investment in rooftop solar, Cambodia’s Ministry of Mines and Energy recently issued new guidelines (the “2023 Solar Guidelines”) in a bid to change this.

The 2023 Solar Guidelines (formally the “Principles for Permitting the Use of Rooftop Solar Power in Cambodia”) are the result of a study by an interinstitutional committee formed specifically for this purpose, working in close cooperation with the United Nations Development Programme.

In addition to the 2023 Solar Guidelines, the government has included references to solar, rooftop solar, and renewable energy in the Environment and Natural Resources Code (the “Environmental Code”), which was adopted on June 29, 2023.

The Environmental Code was years in the making, and after going through various drafting stages the adopted version consists of 865 articles addressing a range of topics, including environmental impact assessments, environmental management and conservation, energy management, waste and pollution management, disaster risk reduction management, and many others. The section on renewable energy specifically addresses the management of rooftop solar systems, tax incentives, and other important issues.

Some of the solar and rooftop solar provisions from the 2023 Solar Guidelines and the Environmental Code are discussed below.

Feeding Excess Power into the National Grid

The 2023 Solar Guidelines, in contrast to the 2018 Solar Regulations, allow for approved rooftop solar projects to feed excess power into the national grid.

This may help companies with their offset goals and commitments to reduce their carbon footprint, and is therefore a favorable and much-needed development. Feeding-in is subject to an approval quota, permitting, and a technical assessment by authorities prior to approval.

No feed-in tariff or net-metering has yet been set, so although feed-in approval may be granted, there is not yet a clear financial benefit to feeding excess power into the national grid.

However, this is very likely to change in the near future, as the Environmental Code provides that the relevant government authorities must establish a pilot project for a preferential tariff system for renewable energy. The system must include a fixed rate for the purchase of power coming from solar or other renewables, and a cost reduction mechanism.

This wording will likely lead to a feed-in tariff, and possibly a net-metering approach, to ensure that excess power fed into the grid leads to either fixed financial compensation or a reduction in electricity costs through net metering.

It appears the 2023 Solar Guidelines are laying the groundwork for this pilot project proscribed for in the Environmental Code, so related developments on this are expected soon.

Compensation Tariff for Variable Energy from Rooftop Solar

Removing the much-debated capacity charge, the 2023 Solar Guidelines require the tariff regulator to set a new tariff for rooftop solar based on a prescribed formula. The new tariff must be based on actual consumption of electricity, not on the total capacity of the project.

Regardless of the formula and numbers that the regulator will use to calculate the new tariff, consumers with rooftop solar will not have to pay a higher rate when compared to the general tariff applicable to users without solar, as per the 2023 Solar Guidelines.

Initial responses by the local solar industry welcomed the removal of the capacity charge and the introduction of the tariff limit for solar. However, businesses are hesitant about whether the new tariff scheme will spur immediate investment in rooftop solar, as the hard numbers for the new tariff have not been issued.

The formula for the “Compensation Tariff for Variable Energy from Rooftop Solar” provided under the 2023 Solar Guidelines is designed to be fair to “all parties”—including existing utility companies and investments that are impacted by solar and thus require compensation. As stated above, the 2023 Solar Guidelines have not set the tariff price; they merely set a formula following guidelines and principles. The actual tariff is for the regulator to determine, and to do so it will include calculations on the leveled cost of electricity (LCOE) and grid loss to compensate parties that may be impacted by solar.

Potential Tax Incentives

The Environmental Code provides that “all materials used for the installation of renewable technologies” are to be given tax incentives.

Although the article does not further clarify the specifics of such incentives, the clear obligation to provide a tax incentive should be warmly welcomed by businesses. We expect the tax regulator to further clarify these tax incentives in the near future.

A Bright Future

The 2023 Solar Guidelines provide the solar industry and government institutions with principles and guidelines related to rooftop solar. We expect that these principles and guidelines will eventually lead to clear rights and obligations as they are implemented through legislation and official policy in the coming years. The basis for incentivizing and promoting solar is clearly provided under the 2023 Solar Guidelines.

The Environmental Code sets clear rights and obligations, applying both directly to citizens, companies, and to government institutions that have to implement and honor them. Addressing solar in such a major piece of legislation marks a great step forward for the country. Providing clear and direct obligations for government institutions to promote and incentivize renewables such as solar will surely have a positive effect on industry and the environment.

RELATED INSIGHTS​ 

August 20, 2026
As part of its membership in Lex Mundi, Tilleke & Gibbins has released the latest edition of its Guide to Doing Business in Thailand, providing an overview of the legal, regulatory, and commercial considerations for companies establishing or expanding operations in Thailand. The 2026 edition offers practical insight into the country’s business environment, investment framework, and operational requirements. The guide covers a wide range of topics relevant to foreign and domestic investors, including: Investment incentives and promotion schemes Financial facilities and banking regulations Exchange controls and money transfers Import and export regulations Business structures and incorporation options Requirements for establishing a business Operational and compliance considerations Business cessation and insolvency procedures Employment and labor laws Taxation Immigration and visa requirements Prepared by Tilleke & Gibbins lawyers across multiple practice areas, the publication outlines key aspects of doing business in Thailand, including foreign investment restrictions, regulatory compliance obligations, corporate structures, employment requirements, and recent legal and economic developments affecting investors. The publication forms part of Lex Mundi’s Country Guides series, a global collection of jurisdiction-specific reference materials prepared by member firms around the world. Together, these guides help companies evaluate opportunities, compare regulatory environments, and plan international business activities across multiple markets. The full Guide to Doing Business in Thailand 2026 is available through the button below.
May 25, 2026
After several years of policy discussion and continued efforts led by the Ministry of Commerce (MOC) to relax the list of reserved businesses under the Foreign Business Act B.E. 2542 (1999) (FBA), the reform process has now reached a significant milestone. On May 12, 2026, the Thai cabinet approved in principle two draft subordinate legislative instruments aimed at delisting certain reserved business activities under the FBA and reducing licensing requirements for foreign business operators. These developments signal a renewed and concrete effort by the government to modernize Thailand’s business regulatory framework in order to attract foreign investment and boost Thailand’s competitiveness in the global market. Nine Businesses Set for FBA Delisting Below is a list of the nine businesses that are being targeted for delisting from the FBA’s restrictions. A draft ministerial regulation would delist the first eight reserved businesses, while a royal decree has been drafted to delist the ninth business: Telecommunications services (Type 1 license only, covering operators without their own telecommunications infrastructure), under the supervision of the Office of the National Broadcasting and Telecommunications Commission. Treasury center services subject to the Foreign Exchange Control Act B.E. 2485 and under the supervision of the Bank of Thailand. Securities-collateralized lending, pursuant to the laws governing securities and exchange and derivatives regulated by the Securities and Exchange Commission. Agency, dealer, advisory, or fund management services relating to derivatives where the underlying assets fall outside the scope of the Derivatives Act B.E. 2546 (2003) Intra-group shared services, including administrative, human resources, and IT functions Intra-group domestic debt guarantee services Leasing of partial space for installation of financial service machines and automatic vending machines for employee use Petroleum drilling services Trading of agricultural product derivatives through a futures exchange, with physical delivery or receipt of agricultural products at a futures exchange–designated
February 10, 2026
Data center and cloud investments are forming a major focus of private-sector investment in Thailand, with tech giants like Amazon, Google, Microsoft, and TikTok, as well as numerous telecom and data center companies, committing significant outlays to data center and cloud development. The country’s Board of Investment (BOI) approved projects worth THB 1.87 trillion in 2025, and THB 746 billion of this was from planned data center investments—by far the largest amount from any single industry. Thailand’s swift rise as a regional data center hub is fueled by surging demand for cloud, AI, and digital services, as well as large-scale investments from global tech firms. The country’s strategic location, competitive power costs, robust fiber infrastructure, expanding IT talent, and supportive government policies—including BOI incentives and streamlined approvals—have made it an attractive destination for scalable and sustainable digital infrastructure investments. The BOI’s proactive approach in updating promoted categories and providing both tax and non-tax incentives further ensures Thailand’s continued growth in this sector. 2025 BOI Changes for Data Centers In the middle of 2025, the BOI responded to the remarkable trend by updating investment‑promotion categories across various sectors (e.g., machinery and electrical equipment, public utilities, digital and innovative industries) to accommodate growing investment in data‑center projects. Before the change, which was detailed in a notification that has applied to investment promotion applications submitted from July 1, 2025, onward, data‑center projects under BOI promotion were granted a single A1 incentive (an eight‑year corporate income‑tax exemption) and subject to one uniform set of conditions. The July 2025 notification restructured promotion for data centers into two categories based on power‑usage efficiency: high‑efficiency data centers and other data centers. Under these rules, qualified high‑efficiency data centers are eligible for an eight‑year corporate income tax (CIT) exemption, while for other data centers this exemption is
November 21, 2025
On November 17, 2025, Thailand’s Ministry of Interior introduced significant regulatory changes to make rooftop solar adoption easier and more cost-effective for property owners. Ministerial Regulation No. 72 B.E. 2568 (2025), issued under the Building Control Act B.E. 2522 (1979), was published in the Government Gazette on November 19, 2025, with immediate effect. Background Under the Building Control Act (BCA), any alteration made to a building requires either notification of the relevant authority or application for a building alteration permit—unless the alteration falls under a separate list of exceptions specified in the ministerial regulations issued under the BCA. In 2015, installation of solar rooftops on any residential building under 160 square meters was added to this list of exceptions, subject to inspection and notification requirements. The newly enacted regulation now eliminates many of these requirements and introduces a broader and more permissive framework to promote solar adoption nationwide. Key Changes Specifically, the regulation introduces three major changes: Expanded exemption from the definition of “building alteration”: The installation of solar panels on any building roof—regardless of the type of building or the total area of the installation—is no longer considered a building alteration under the BCA, provided that the total weight of the installation does not exceed 20 kg/m2. Removal of structural integrity certification requirement: The new regulation eliminates the obligation to obtain a structural stability certificate from a licensed civil engineer. Removal of notification requirement: Property owners or possessors are no longer required to notify the local authority before installation of a solar rooftop. Impact This significant streamlining of requirements for solar rooftop installation is expected to accelerate the adoption of renewable energy in the country, particularly for residential and commercial properties—similar to the way Thailand’s December 2024 removal of licensing requirements for factory solar rooftop installations encouraged such