Rhaydz B. Barcia

Published: February 9, 2023

ALBAY: Asia’s first commercial-scale geothermal steam field, which was discovered 50 years ago in a quiet and small town in Albay province, continues to provide clean and renewable energy to 2.7 million homes in the Philippines.

The geothermal field has also been instrumental in the development of Albay, specifically in the remote municipality of Tiwi which was once considered as the poorest town in the province.

Mayor Jaime Villanueva said Tiwi transformed from being a sixth class town into a first class municipality in 1996. Tiwi currently has an income of over P200 million annually, including the internal revenue allotment (IRA).

Geothermal is the biggest industry in Tiwi and a major source of local employment.

The Philippine Geothermal Production Corp. (PGPC), which operates the plant, and its partners have been complying with the Tiwi First Policy which requires businesses to prioritize the employment of the town’s residents.

More than half of PGPC’s personnel, 58 percent, originated from Tiwi and 62 percent are currently residing within the town, according to the latest data.

Villanueva said the partnership between the local government and the PGPC resulted in the industrialization of their town, thus, helping develop the skills of the residents in construction, mechanical and drilling works.

The mayor said the operations at the Tiwi steam fields provide subsidies to 16 villages through the national wealth fund. This fund can be used to lower electricity rates by at least 80 percent.

PGPC also provides scholarships to students.

Birth of geothermal

In 1962, a team from the Commission on Volcanology, now the Philippine Institute of Volcanology and Seismology, spearheaded an expedition in Mount Malinao with the goal of harnessing the area’s abundant geothermal energy.

The Geothermal Energy, Natural Gas and Methane Gas Law which, among others, promotes and regulates the exploration, development and utilization of geothermal energy in the country, was enacted in 1967. It was also in the same year that Dr. Arturo P. Alcaraz and his team first illuminated an electric bulb using steam-powered electricity coming from Mount Malinao.


Tiwi’s commercial geothermal operations officially began in 1979.

At present, the Tiwi power plant, located at the slope of Mount Malinao, has an installed capacity of 234 MW, making it the third-largest geothermal facility in the Philippines.

Aside from the Tiwi steam fields, Bicol Region is also home to the Bacon-Manito Geothermal Power Plant situated in the Pocdol volcanic range, some 100 kilometers away from Tiwi.

Geothermal energy is abundant in the region which has several dormant volcanoes.

The geothermal fluid underneath the ground is tapped via wells and is sent through insulated pipelines to primary pressure vessels that separates steam from brine. The steam then travels through insulated lines to the secondary pressure vessels where it is purified.

The steam delivered to the power plants passes through and rotates the turbines coupled to generators that produce electricity. And through transformers and power transmission lines, electricity is then distributed to homes, offices and industries.

Guarding the geothermal field

PGPC public affairs supervisor Erwin Vargas said the intact forest cover and abundant source of water continuously fuel the 50-year-old geothermal field.

The Agta-Tabangnon Indigenous peoples have been tapped to protect the area that houses the geothermal field.

Arsenio Condeno, the Agta-Tabangnon chieftain of Joroan, said the presence of the geothermal power plant in Tiwi is advantageous to their community, as their rainforests and secondary forests are being preserved. Their livelihood and culture are intertwined with the forest, he said.

“We acquired scientific knowledge through the training of the PGPC and the government. So, we integrate our indigenous practices with these new learnings to improve our survival techniques in times of natural calamities,” Cordeno said.

The geothermal forest reserve covers at least 17,661 hectares of land in the towns of Tiwi and Malinao. Vargas said the forest reserve is also home to many animals like wild boars, monkeys, eagles, snakes and several bird species.

“This is a good sign that our biodiversity is still good and protected. In Tiwi, Albay, the biodiversity is still protected due to the presence of geothermal,” Vargas said.

He added the Indigenous community will be tasked to nurture newly planted trees within the reserve and will be given corresponding payment as guardians of the forest.

PGPC also replanted abaca within the geothermal field to help communities generate income, provided that they do not vandalize the facilities.

“We invested in comprehensive and integrated high-value programs and partnerships to promote human progress, sustainable development and positive change in our host communities,” Vargas said.

Future of geothermal

Geothermal energy represents 13 percent of the Philippines’ energy mix.

Aside from the Tiwi plant, PGPC also runs the Mak-Ban steam field in Laguna.

The cumulative gross generation of Tiwi and Mak-Ban steam fields reached 142 billion kWh as of September 2021. This is equivalent to 264 million barrels of oil imports, and has helped reduce CO2 emissions by at least 56 billion kilograms.

The Aboitiz Power Corp. (Aboitiz Power), through its subsidiary AP Renewables Inc., is establishing the 17 MW Tiwi Binary Geothermal Power Plant Project within the 1.5 hectares of land where the Tiwi Geothermal Power Plant is located.

The town mayor said that during the early years of Tiwi geothermal operations, the plant generated at least 300 MW production but after 50 years, the generated electricity significantly declined to 115 MW.

When asked if the construction of a binary plant will boost the power generation in the country specifically in the countryside, Villanueva said the liquid waste or brine will be harnessed and used through the binary facility to produce another source of power before it will be reinjected into the wells.

Jeffrey Estrella, APRI president, said the Tiwi Binary Power Plant is a facility designed to extract the reconvertable heat from the geothermal brine that is processed in a closed-loop system. Through this process, no harmful gas or liquid is being emitted nor any waste products are discharged to the atmosphere.

The concept of recovering heat from the geothermal brine and converting it into electricity is a novel solution that improves its overall thermal efficiency.

Vargas also explained that the binary is dependent on the supply of brine from the steam generating system. He added the corporation is enhancing its existing wells and drilling new wells to produce more steam.

The 17-MW binary geothermal power plant is targeted to be operational by the end of 2023.

Mario Marasigan, assistant secretary of the Department of Energy, said the government is aspiring to develop and generate 100,000 MW of renewable energy by 2040.

The energy official said the binary geothermal plant will have a massive contribution to the power requirements in Luzon and in the Visayas.

“The capacity is not that big and will not solve the capacity and power requirement of the country, but it will greatly help out the supply of energy not only in Bicol but also in the Luzon grid including in the Visayas. So, this is a big contribution to our power requirement,” Marasigan said.

Hopes are high when it comes to maintaining and improving power generation through geothermal energy, especially as the urgency to address climate change looms large.

This story is produced by Rhaydz Barcia as 2023 Journalism Fellow on Just and Sustainable Energy Transition of the Climate Tracker Asia in partnership with Rosa Luxemburg Stiftung.


This article is sponsored by the Rosa Luxemburg Stiftung Manila with funds of the Federal Ministry for Economic Cooperation and Development of the Federal Republic of Germany.

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