Rice does not just provide energy for our bodies; it can also power a nation’s electricity grid. In Thailand where there is a push for more renewable sources of energy, agricultural wastes have been put to good use. With government support and incentives, more than 300 small plants using renewable sources supplement a power generation system straining under growing demand, while solving the problem of agricultural wastes. Read more

Thailand: Power from waste; 300 plants feed into grid running on renewable sources like sun and wind

By Tan Hui Yee, Thailand Correspondent, in The Straits Times (22 March 2013:

NAKHON RATCHASIMA – From its nondescript entrance, Tong Hua in north-eastern Thailand looks just like any other rice mill in the country.

Walk about 100m into its sprawling compound, however, and you notice something different: A smokestack nudges an otherwise clear skyline, part of a small power plant that turns rice husks into electricity on the spot.

Tong Hua, incidentally, supplies the grain that goes into the SongHe brand of rice sold in Singapore. Its energy production is a testament to the growth of Thailand’s electricity sector, which analysts tout as the most progressive in the region.

Incentives and loans allow small operators to run more than 300 small plants using renewable sources like the sun, wind or agricultural waste. These plants in turn feed electricity back into the main grid, helping to supplement a power generation system that is straining under growing demand.

“It is an example for the region,” says Dr Chris Greacen, founder of non-profit renewable energy group Palang Thai.

Just last month, however, Thailand’s Energy Minister Pongsak Raktapongpaisarn warned a routine gas pipeline maintenance in April may cause partial blackouts. While some bemoaned official ineptitude for the possible disruption, others alleged it was a ploy to fast-track approval for controversial coal or hydropower plants.

Former energy minister Piyasvasti Amranand argues it is time to put the focus back on growing the alternative energy sector and moving away from natural gas, which accounted for some 68 per cent of power generated last year.

According to the Energy Policy and Planning Office, about 5 per cent of Thailand’s electricity is currently generated from renewable resources, if hydropower is not taken into account.

Thailand’s farms and factories seem to have tapped just about every type of waste to produce power. Rice mills burn husks for energy. Sugar mills do the same with bagasse, the fibre left over after sugar cane is crushed. Pig farms use the biogas generated by manure to create electricity.

These developments were nurtured through the gradual liberalisation of the energy sector from the 1990s, allowing small power producers to be paid premiums on top of fixed rates for their power.

At Tong Hua, a conveyor system transports about 200 tonnes of husk daily from its rice mill to a furnace, which burns it at 950 deg C to produce electricity. The firm uses 60 per cent of the electricity generated by its 7.7MW plant and sells the rest to the Provincial Electricity Authority. It sells electricity to the authorities at 2.9 baht (12 Singapore cents) per kilowatt hour but gets another 0.3 baht as part of the incentive scheme.

But its managing director Suthep Wiroadpaisit says it was motivated more by the need to fix an unstable power supply about 10 years ago and for an outlet for the husks. “We had no electricity, nowhere to put our own rice husks. We had to solve our own problem,” he tells The Straits Times.

These alternative energy plants have, in turn, pushed up the prices of agricultural waste. Rice husk, for example, now costs 1,300 baht a tonne compared to just 50 baht eight years ago, says Mr Suthep.

Although Thailand aims to have renewable energy account for a quarter of total energy consumed by the next decade, officials say it has to keep a lid on the premiums paid for alternative energy production so consumers do not end up paying more. It also has to calibrate the amounts of energy from different sources to reduce supply disruption chances.

“What will happen if it is not sunny, or if there is no wind’” Energy Ministry permanent secretary Norkhun Sitthipong points out. “This is not just about capacity, but reliability as well.”

Source: www.power-eng.com