Garden waste biomass for renewable and sustainable energy production in China: Potential, challenges and development

Garden waste biomass is a potentially underutilized renewable biofuel feedstock, which is increasing dramatically with rapid urbanization worldwide. China has experienced fast-paced urbanization over the past three decades: the settlement area has increased at a rate of 6.1% annually, with greenspace increasing by 12.7% annually from 1996 to 2008. This paper provides a synthesis of literature and experimental data to trace the potential of garden waste biomass for green renewable energy production in China. Our results show that the total potential biofuel produced by garden waste biomass was estimated at 260 petajoules (PJ), accounting for 20.7% of China's urban residential electricity consumption, or 12.6% of China's transport gasoline demand in 2008. Thus the use of garden waste biomass for energy production will contribute to the construction of low-carbon cities. However, there are still many difficulties—the main challenges are how to quantify the available garden waste biomass accurately, and technical and financial issues with the exploitation of garden waste biomass for energy production. Finally, we provide several practical suggestions for the future development of garden waste biomass for energy production. The use of garden waste for energy production in urban areas could be a win–win approach for mitigating both the burden of disposed costs and the energy crisis.