Biogas offers solution to limited energy

Tag : Biogas Generator

(15-06-2008)
As energy prices continue to rise and the world turns its attentionto cleaner sources, biogas offers advantages for small businessowners across the country. To Hang reveals the details.
With his business dependant on a constant supply of electricity,animal breeder Nguyen The Ha is usually pretty worried this time ofyear.
As the summer approaches along with his busiest season, Ha isunusually calm this year. Although power outages may be inevitable,Ha can relax this summer thanks to a new electric generator fuelledby something Ha has in abundance: animal waste.
"When I learned about the biogas-electric generator created byDa Nang University's Professor Bui Van Ga on VTV, I quicklyrealised that I needed it," said Ha, director of the ThanhHoa-based Nam Khanh Company.
With his farm's success at stake, Ha quickly made his way to DaNang and asked the scientist to install the innovative generator.With biogas collected from animal waste already used for cooking,using the gas to fuel his generator made perfect sense.
"The waste produced by around 700 pigs and hundreds of animalbreeds (chickens, infant ostriches, fish, porcupines) is so muchthat we can't use it all for cooking," Ha explained. "Wehad to set the rest of the waste on fire to keep the areaclean."
Why biogas?
In Viet Nam, biogas - an alternative fuel for cooking - has beenused widely since the 1980s. In the early 21st century it becamemore popular thanks to the assistance of developed countriesworking to alleviate green house effects. Viet Nam was honoured bythe United Nations for its effort in environmental protection bydeveloping biogas in 2006.
Biogas has historically been used in internal combustion engines.However, the use has been limited to large-sized engines which usegas extracted from dumping grounds or sewage. Until now,small-sized engines using biogas were uncommon.
"Converting small engines which used to run on diesel andpetroleum into ones running on biogas is an important advancementfor Viet Nam's countryside," said Huynh Phuoc, Director of DaNang's Science and Technology Department. "Eighty per cent ofthe population lives in rural areas."
Phuoc explained that the national electricity grid hasn't reachedmany remote, mountainous regions, and where it does reach pricesare high. As every part of the country sees regular power outages,farmers often face difficulties in production.
To use biogas as an alternative to diesel engines, Bui Van Ga,director of Da Nang University, had to solve two problems:filtering impurities, (particularly H2S) and introducing aregulating kit to ensure stable electric current.
"If one of the two problems is not completely solved, theengine could technically run, but with some serious problems,"Ga said. "Worse is that the engine's life span is shortened.The loss caused by the broken-down machine would be higher than thebenefit gained by saving energy."
With the regulator and filter made of popular materials, thetechnology is an affordable alternative for farmers.
This isn't Ga's first breakthrough in applying biogas to everydayuse. He and his colleagues started researching gas-run engines in1997. He was granted exclusive property rights by the NationalOffice of Intellectual Property for the liquid petroleum gas (LPG)conversion kits he invented for motorcycles, which were not onlycost effective but also environmentally friendly.
"Based on this success we continued to research applyingbiogas for stationary engines," he explained.
Ga worked with four researchers at Da Nang University's Centre forEnvironmental Protection Studies. They received support from theMinistry of Education and Training as well as from Da Nangauthorities for a total of VND120 million (US$7,500).
After all this work, according to Ga's calculations, farmers cannow use the waste from around 20 pigs to regularly power asmall-sized electric generator.
An engine consumes 1m.cu of biogas to generate an average of 1kWh.A 20m.cu bag of biogas can fuel a 5kW-generator for six consecutivehours. It would take 10 litres of diesel to produce the same amountof electricity.
With the average small farm running for six hours, farmers can saveVND2 million ($110) a month, amounting to VND24 million ($1,400) ayear.
Since biogas also helps cut down on CO2 emissions, enginesproducing 26.4kg of CO2 a day will cut down on 9.5 tonnes annually.
Biogas-electric generators are already in use at farms in Da NangCity's Hoa Vang District and rural areas in the central region.Ga's group has so far received 20 orders from across the country.
Customers in the northern regions have bought the conversion kitsand are installing them on their generators themselves. With thecentre's technicians living too far away, they can only providefarmers with remote assistance.
Gas in action
The NSB Company has about 500 pigs in Hoa Phong Commune, Hoa VangDistrict. They've been using the electric generator running onbiogas for nearly a year and so far have had no complaints
"Each day 5kW-generators run for around 12-15 hours. Theelectricity is used for cleaning, warming and fanning thepigsty," said Huynh Ngoc Lanh, NSB director.
"We have used biogas for cooking for years, but the redundantgas was lost," Lanh noted. "Now it is converted toelectricity. Many farm owners have come to see what we'redoing."
Ha, director of the Nam Khanh Company, plans to meet up with Gaagain to replace his 7.5kW generator with a 15kW one.
"A bigger generator will ensure energy for the wholefarm," Ha said.
Thanks to the money saved on fuel, Ha isn't worried about payingfor the VND20 million ($1,100) generator and another VND2 million($110) for the conversion kit. The new electric generator has cuthis energy costs by half. Even more valuable is the assurance thatthey won't have to worry about black-outs anymore.
Future plans
The filters and conversion kits are produced at the university'scentre for experimental vehicle engines. The research group plansto establish a production unit so that they can transfer thetechnology to convert LPG/gas motors and stationary engines.
"It's still difficult to make research into reality becausethere are no domestic enterprises working to apply new research toproduction," Ga complained.
"Scientists are reluctant to commercialise their research. Butif we don't produce them ourselves how can we prove our work'seffectiveness?"
According to Ga, Toyota Corporation recently decided to support hisgroup in their effort to multiply the model at every farm in ruralareas throughout the country.
The Ministry of Education and Training also asked them to introducethe breakthrough at ASEAN's science and technology programme tolend the model to other regional countries.
Ga's group is co-operating with Japan's Osaka Prefecture toresearch the possibility of extracting methane from biogas. Biogascould then be stored in ordinary gas storage containers with fivetimes the capacity than present. Biogas could even one day be usedin small-sized automobiles.
The breakthrough would realise Ga's dream of soon seeing an entiregeneration of motors running on biogas, bringing a steady supply ofelectricity to every corner of the countryside.  VNS