Turning waste into Energy
The following article was originally published in CoJen, the customer magazine by GE Energy’s Jenbacher gas engine business.
The area around the Tha-Chang palm oil processing mill in Thailand used to emit a pungent odor. Even worse, wastewater from the plant discharged methane – a leading cause of global warming – into the air. But that was before Thai Biogas Energy Company (TBEC), using GE’s Jenbacher gas engines, began.
Today, there’s no longer a strong odor. There are no environmentally detrimental emissions. And palm oil producers are able to make money by generating power from the wastewater produced from processing palm oil.
The palm oil business is a major industry in Thailand, second only in the world to Malaysia and Indonesia. Palm oil, which is used for cooking in most Southeast Asian kitchens, comes from the fruit from palm trees. Fruit bunches grow on the palm trees for six to eight months until they are ripe and weigh 30 to 40 kg, and then they are cut off and collected. At a processing mill, the fruit bunch is steamed and the crude oil is pressed out of it. Wastewater that is created in the process is pumped into a lagoon.
The Tha-Chang Mill Project
In Thailand, temperatures reach 90 degrees Fahrenheit – or higher – each day. The steamy wastewater creates bacteria, which quickly begins to smell, and the bacteria creates methane, which climbs into the atmosphere. Or that’s what used to happen at the Tha-Chang mill. TBEC has covered the wastewater lagoon with what looks like a huge blanket. The methane that is emitted from the lagoon is collected and sucked out from under the blanket into a Jenbacher engine where it, along with oxygen, can be burned directly. Forty to 45 tons of palm oil fruit can create the equivalent of 1 MW of electrical power within an hour. The Tha-Chang mill produces 60 tons per hour.
The palm oil mills involved can collect carbon credits for the power produced, which can be turned into money. In Thailand, too, an innovative government program allows palm oil mills to connect their power to the grid – and sell it. Since this energy comes from a renewable energy source, they are also entitled to an add-on tariff. “Obviously, the palm oil producers are very eager to do this,” says Dietmar Rauter, GE Energy Sales Manager – Southeast Asia. “They are taking what used to be a malodorous area that emitted gases into the environment, and turning it into electricity. It is a winning situation for them.” Payback on the initial investment is usually within two to two-and-a-half years.
TBEC, one of the leading biogas companies in Thailand, has four operating projects that create biogas and electricity. In addition, annual carbon credits from TBEC’s projects exceed 130,000 per year. The company develops, designs, finances, implements, operates and maintains the projects. “Thailand’s shape really benefits this conversion of methane to electricity,” Rauter says. “The palm oil mills are mainly in the south of Thailand – fairly near tourist areas and major cities – and are very well connected to the electric grid.”
The journey has just begun
GE sold its first Jenbacher engines for Thailand’s palm oil industry in 2006 – coinciding with the passage of Thailand’s carbon credit laws. Today, GE has about 20 installations, some of which use several Jenbacher engines. The plants range in size from 500 kW up to 6 MW of power. Very large plants process some 200 tons of fruit per hour. “Carbon credit trading development has been a major factor in this industry, since it is a big part of the payback to the palm oil producers,” Rauter says. Educating those palm oil producers about the benefits of becoming electricity producers has been a challenge, but more and more palm oil mills are recognizing that they can profit from the system. And this business gets more and more interesting in other countries, such as Malaysia, as well. The system used at palm oil mills is also easily replicated for other industries, such as tapioca starch factories. Meanwhile, however, palm oil farmers in Thailand are reaping the benefits from TBEC’s projects as their smelly lagoons are replaced with the smell of money.