Waste is one of the key sources of energy being promoted by the Thai government as it aims to address the excessive waste problem faced by many cities across the country. This is part of the national agenda in accordance with the national waste disposal and management policy. The concept of waste management has been embraced by Thailand through the establishment of a national master plan for solid waste management. In accordance with the master plan, several waste-to-energy (WtE) projects have been initiated.

The Pollution Control Department, Thailand, estimated that 28.7 million tonnes (mt) of solid waste was generated annually from urban areas; it also pointed out that plastic waste had a significant impact on the environment. Over 2 mt of waste was properly disposed of but only 25 per cent was recycled. Despite the increased recycling, a significant amount of waste was disposed of inappropriately and had a detrimental impact on groundwater.

The significant increase in the generation of solid waste, the presence of unattended waste and inappropriate disposal of waste at several sites nationwide has driven the need to address waste management, including the government’s increased focus on WtE plants.

Thailand’s WtE sector has a promising future as the Ministry of Energy believes renewable energy, including that from biomass, biogas and municipal solid waste (MSW), can contribute to an increase in the country’s green energy. Thailand’s Alternative Energy Development Plan 2015-2036 has proposed a target of 30 per cent share for renewable or green energy in total energy consumption by 2036. Investments in WtE projects have been encouraged by the introduction of a feed-in tariff rate for electricity generated through sustainable processes to promote energy recovery from MSW.

Recent trends and developments

Currently, most local areas generate too little waste to make power generation from waste material a viable investment option (daily waste of at least 300 tonnes is required for viability). The Ministry of Interior has organised clusters of local administrations to come up with energy solutions for waste disposal by mandating that distance for transport of waste must not exceed 30 km. However, the attempt has not gone beyond the signing of memorandums of understanding, primarily because the onus of carrying the initiative forward has been left to the custodians of each cluster.

Various stakeholders have shown keen interest in developing WtE projects. Thailand’s National Energy Policy Council (NEPC) is planning to increase the number of new WtE projects to ease worries about the growing volume of garbage. The NEPC has invited investors to propose new projects for a total capacity of 400 MW. Currently, WtE plants, which were granted licences in previous auctions, operate in 36 areas with a combined capacity of 328 MW. Upcoming projects promise a new business opportunity to power companies that want to be part of the growing trend towards renewable energy.

In March 2021, the Metropolitan Energy Authority, along with private firm Newsky Energy Thailand, invested in the construction of two new WtE power plants in Bangkok. The two power plants will be introduced along with a smart grid system, which allows communities in service areas to receive power entirely from these plants, independent of the main power lines. The proposed new WtE plants are currently in the public consultation process. Construction of these projects is expected to commence in the second half of 2021, and they are expected to be linked to the electricity grid by 2024.

The Asian Development Bank (ADB) is also funding a WtE plant project in southern Thailand. The project entails the construction and operation of a 25 MW biomass power project located in Songkhla province of southern Thailand. The primary source of feedstock will be rubberwood waste sourced from local farmers, sawmills, and intermediary suppliers located within the project area. All electricity produced by the project will be purchased by the Electricity Generating Authority of Thailand under the small power producers programme. ADB will be providing financial assistance of THB 1.1 billion for the project.

In another major development, the ALCP6 WtE project in Krabi province of southern Thailand commenced construction activities after achieving financial closure in December 2020. The ALCP6 plant will consume around 144,000 tonnes of MSW per year. The waste will be incinerated, and the heat obtained will be converted into 6 MW of electricity to be exported to the national grid.

Key issues and challenges

Conversion of waste to energy through incineration is now an established method in developed countries for reducing waste mass and volume whilst simultaneously providing heat and power. However, the uptake of WtE technologies in developing countries has not been very successful. Experts in Thailand have urged the authorities to slow down their large-scale WtE development policy as it could severely harm the country’s environment and people’s health.

The capital investment required for a project has also raised issues pertaining to financial structures and associated arrangements. Several WtE projects in Thailand have faced delays due to funding issues and the government has had to introduce various subsidies in order to make WtE plants more lucrative for investors.

Depending on the feedstock and technology, WtE processes may create air pollution, contaminated water or other residues. Owing to the environmental hazards of WtE plants, such projects have faced backlash from local residents, often leading to their being shelved.

Future directives for the size and structure of facilities to generate power from waste should ensure environmentally sound operations and acceptance by surrounding communities. The sites should be large enough to accommodate management of waste and trees should be planted to create buffer zones between the sites and adjacent communities in order to minimise their exposure to odour and suspended particulates.

Further, waste in Thailand is full of organic and other non-flammable material due to which incineration plants cannot reach the high temperatures necessary to produce electricity and avoid toxic emissions and ash by-products. This has led to incineration plants offsetting their economic losses from inefficiently sorted local waste by illegally importing better-sorted waste.

The road ahead

Thailand has established subsidies and tax incentives for various WtE plants that include incineration, gasification, fermentation and landfill gas capture. The country has also set 500 MW as the target for WtE in the new Power Development Plan 2018-37, which represents 30 per cent of total renewable energy resources by 2037. Currently, the tentative feed-in tariff given for the WtE plants is THB 3.66 per kWh. The Thai government’s initiatives are expected to establish a promising market for WtE plants in the coming years.