Abstract
In this research, the energy and material flows in the glasshouse horticulture of flowers and ornamental plants were identified based on the field and interview survey at a specific site located in Arida district of Wakayama Prefecture, Japan. In addition, a quantitative analysis was conducted to estimate the GHG emissions derived from each energy and material consumed in cultivation process, applying Life Cycle Assessment (LCA). Furthermore, we developed seven alternative options of heating equipment used in glasshouse horticulture and then evaluated GHG emissions reduction potential through introducing low-carbon equipments in substitution for conventional oil boiler and utilizing woody and waste biomass for fuel based on the result of LCA. From the analysis, we reached the following conclusions: (i) The GHG emissions from glasshouse horticulture account for 98% of the entire emissions and almost all of them is induced by heavy oil combustion in conventional boilers for heat generation. (ii) The installation of wood chip boilers into glasshouse horticulture plant and promotion of woody biomass utilization can reduce GHG emissions by 64%, compared with conventional oil combustion. (iii) As an electric heat pump produces heat greater than the electricity consumed, 59% of GHG emissions can be reduced through replacing conventional oil boiler by it. (iv) The monetary value of carbon credits gained by installing wood chip boilers into glasshouse horticulture plant is estimated at about 36 thousand yen per year if the domestic market price of credits is 1.5 thousand yen per ton CO2.
