Giant King Grass – a biomass pellet feedstock
The US based company VIASPACE Green Energy Inc., markets its proprietary Giant King Grass (GKG) - a high-yield, dedicated energy crop - as a low carbon, renewable biomass replacement for coal and a non-food feedstock for biogas and second-generation liquid biofuels. The company also manufactures and sells biomass pellets made from GKG at a facility in Guangdong, China.
In 2009, Sung Hsien Chang, President of VIASPACE Green Energy, and Zhan-Pei Xiao General Manager, started looking for fields to grow Giant King Grass in the southern Chinese province of Guangdong. Xiao visited several counties in Guangdong and finally signed a 50-year lease for 1 500 Mu (100 ha) of farmland with a local community in Shi-Gu-Tang outside the city of Yingde located 180 km from Guangzhou City. Although the annual rent is a seemingly modest CNY 80 (c. EUR 9.6) per Mu, according to the company local farmers received the first 10-year instalment upfront and are happy with the deal.
Easy to plant
– It is quite easy to plant Giant King Grass. We sowed seeds for 2 Mu fields. Buds sprouted after two weeks. Then, we transplanted the seedlings to larger fields. Giant King Grass grows very fast, and can be harvested every 3 months, 2-3 times per year. The new leaves will grow after harvest. Once planted, there is no need to plant them again. You can also take the cuttings to propagate more Giant King Grass, explained Hu Rong-Gui, Farm Manager, for the facility.
Soon after the successful establishment of the grass plantation, Xiao started looking for suitable pellet technology suppliers. He sent feedstock samples to several pelletizing machinery companies in China, and finally chose Muyang as technology supplier. The pellet plant was built in the middle of the grass plantation and in 2011 a 2 tonne per hour MUZL610M Pelletizing line was installed. A turnkey line it includes pressing, chopping, grinding, drying and pelletizing. The total investment was around US$300 000.
Production at night
– It is too hot in the daytime during the summer. Moreover, the night electricity fee is CNY 0.3/kWh, which is CNY 0.9 cheaper than during the daytime. So we run the pelletizing line from 10pm-8am. We produce around 10 000 tonnes pellets annually, Zhan-Pei Xiao explained.
The total moisture of the Giant King Grass Pellets is 8.8 percent and Gross Calorific Value is 4.72 kWh/kg according to testing by China National Coal Quality Supervision and Testing Center. The pellets are sold to clients within 250-300 km radius in Pearl River Delta region. The pellet price ex-works is CNY 850 (EUR 103) per tonne and the transportation fee is CNY 80-100 (EUR 9.6-12.1) per tonne. According to Xiao’s calculation, the overall production cost of its Giant King Grass pellets is around CNY 250 (EUR 30.2) per tonne.
In total the company has invested over CNY 13 million (EUR 1.57 million) in the Giant King Grass Pellets project. Although it is a sustainable and reliable business, the company has deferred on plans to expand the plantation and increase pellets production. The reason is simply that it is proving very difficult to obtain a long-term lease on large amounts of land for a low price in China.
Text & photos: Xinyi Shen