Rice Husks Tapped as Power Source in Rural Areas

chrey commune, Battambang prov­ince – In recent months, Song Heng has had a steady stream of visitors to his rice mill on National Road 5, about 5 km north of Battambang town.

Competitors, government officials, brick factory owners and environmentalists have all come to check out a fancy piece of equipment he installed in September.

Fastened on a fresh slab of white concrete behind his mill and sheltered by a tin roof stands Song Heng’s rice husk gasifier, which provides the 200 kilowatts of electricity needed to run the mill. It works by turning tiny rice husks—a waste product of the rice Song Heng processes—into an efficient, low-polluting gas, which fuels his generator.

“Many rice mill owners come to see this,” said Song Heng, who has owned the mill in Thma Koul district since 1982. “But they say it’s too expensive to install.”

Government officials, businesses and residents are beginning to look at renewable energy technologies like Song Heng’s new gasifier to provide electricity in rural Cambo­dia. Advocates say they produce energy that is cheaper, cleaner and more efficient than diesel generation.

But so far, the new technology has been a hard sell in Cambodia. Most businessmen are scared off by the expensive initial investment of more than $100,000. And Cam­bodia’s import tax adds a hefty 35 percent to gasification systems shipped into the country, according to an NGO and a government official.

But for Song Heng, the gasifier has been well worth the cost. Before buying it, he was spending $5,000 a month on diesel for his generator. Today, he spends only about $1,500 a month on diesel. In two years, he’ll have recovered his investment of $70,000, he said.

Song Heng admits he was skeptical when he heard about the technology. But after touring rice mills in India and seeing the technology in use, Song Heng ordered his own system. He bought it through SME Renewable Energy, a company founded by the NGO Small and Medium Enterprise Cambodia.

The gasifiers that SME markets-produced in India by Ankur Scientific-are available in many sizes, producing anywhere from 7 kilowatts to over 1 megawatt of electricity, said Erik Middelink, energy consultant at SME Renewable Energy.

Gasifiers work by partially burning rice husks or other agricultural products. The husks are heated to 1,000 to 1,100 degrees Celsius, which breaks them down into molecules of carbon monoxide, carbon dioxide, hydrogen and nitrogen, Middelink said. These gases are then cooled and filtered several times to clean out tar and water, he said. The final gas-a mixture of hydrogen, carbon monoxide and methane-is pumped into the generator where it is burned with a small amount of diesel gas.

For the investment to be worthwhile for a business, it needs to use electricity at least eight hours a day, Middelink said.

The emissions are much cleaner than traditional oil-burning generators, Middelink said. There are no sulfur emissions, which contribute to acid rain, soot and can cause asthma, he added. Some carbon dioxide is released, but, he said, “the same amount is being absorbed by the plants, trees and rice [grown for fuel]. So it’s a closed system.”

Because Song Heng has significantly reduced his carbon emissions, he is able to sell a carbon dioxide credit for about $600 a year. Industries that produce high amounts of carbon dioxide buy these credits to reduce, on paper at least, their emissions.

Song Heng sells his credit to E+Co, an NGO that invests in renewable energy projects and which sells credits internationally.

“I can reduce pollution and then make money without wasting raw material-there’s nothing better than this operation,” Song Heng said.

Middelink said rice mills obviously stand to benefit from the gasifiers because they have a secure and free supply of rice husks. Saw mills, brick and cement factories would likely benefit-using sawdust, rice husks or other cheap agricultural products to fuel their gasifiers.

“Anybody who uses a large amount of diesel, like ice plants, which run 24 hours a day [would benefit]. If you make the calculation for them, the investment pays back in a year,” he said.

Sat Samy, under secretary of state with the Ministry of Industry, Mines and Energy, said that Cambodia wants to promote agricultural gasifiers-along with solar energy and mini-hydroelectric generators-as part of it’s push to electrify rural areas.

About 80 percent of the country lacks electricity, Sat Samy said. The government wants to have all of the country’s villages electrified by 2020 and 70 percent of the homes electrified by 2030, he said.

Chandra Govindarajalu, a renewable energy consultant with the World Bank, said there is potential for renewable energy in Cambodia. However, he said, the technology needs to be marketed better and Cambodia needs technicians who can maintain and repair the systems.

“These are promising technologies,” Govindarajalu said. “They could be a strong contributor to the national energy needs…but we are at an early stage of market development and it depends on how quickly it can develop.”

There are also some policy barriers, such as a high import tax on gasifiers, Govindarajalu said. Gasifier systems imported into the country are taxed at 35 percent, Sat Samy said. Prime Minister Hun Sen has agreed in principle to reduce the tax, but the exact amount has yet to be determined, he added.

To date, SME Renewable Energy has sold only two gasification systems to Cambodian factories. Aside from Song Heng’s system, the second was ordered for a brick factory in Banteay Meanchey province. SME Cambodia also helped the village of Anlong Tamei in Battambang province’s Banan district set up a gasifier that residents and businesses can tap into.

E+Co and SME offer loan financing for those interested in the system. But the steep investment cost-a 30 percent down payment is required by SME, which for large projects could runs into tens of thousands of dollars-scares off companies that might benefit.

Middelink had hoped that having a gasifier in operation would attract other factory owners to the system. So far, that hasn’t been the case, and businessmen have been deterred by the initial investment.

Song Heng, however, saw beyond the startup costs.

“Song Heng, he’s a real businessman. He said, ‘If I invest $70,000, I save $3,500 a month.’ He pays $1,200 a month each month on the loan. That’s $2,000 in his pocket every month,” Middelink said.

“That’s what pays for his investment,” he said.

 

Related Stories

Latest News