Page 227 - Biofuels for a More Sustainable Future

Inedible vegetable-oil based biodiesel in Northern Viet Nam 203

decreases, and the cultivation area needs to be extended to fulfill the annual
fuel demand. As discussed in Section 5.1, agriculture practice and oil extrac-
tion processes were the highest and the second highest contributors to eco-
system quality and human health impacts, respectively. Hence, the more
area used for propagation, the more impacts on ecosystem quality. More-
over, if the same intercropping system is applied to an extended area, the
increase of Vernicia seeds would raise the amount of solvent used for oil
extraction, further impacting human health. Additionally, the expansion
of the oil crop cultivation area could mean cropland conversion and food
crop conflict. This system would likewise only produce more coproducts
without any efficiency of fuel production. Similar to the change in Hibiscus
yield, the decrease of Pongamia seed yield also increase biodiesel system
impacts on ecosystem quality in Quang Ninh and vice versa.
On the other hand, the revenue of all biodiesel systems was noticeably
affected by the change in Hibiscus yield, Vernicia yield, Pongamia yield, and
the price of coproducts. Furthermore, when biodiesel production plant was
relocated to upland provinces (case 9), near the cultivation areas, a consid-
erable growth of revenue was observed, more than threefold in Ha Noi
B100 system, due to the reduction of seed transportation and labor costs.
Concerning no coproducts obtained from oil extraction scenario (case
11), hereinafter referred to as oil only biodiesel system, this assumption
resulted in a noticeable decrease in human health impacts of both Hanoi
and Quang Ninh biodiesel systems. Nevertheless, there was a different trend
of system revenues between Ha Noi biodiesel and Quang Ninh biodiesel
whereas a threefold increase in Hibiscus-Vernicia biodiesel and a twofold
decrease in Pongamia biodiesel were reported. Since the relevant chemical
compositions in Pongamia seed is high (Table 6.1), an appropriate volume of
coproducts was obtained that could cover all costs of the production. How-
ever, those coproducts from Hibiscus and Vernicia seeds were not enough to
pay off the investment. Hence, the oil only biodiesel system could make
higher revenue in case of Hibiscus-Vernicia biodiesel.
Regarding the results of Triple I (Fig. 6.8), as alternatives to petrodiesel,
the use of biodiesel of all blends from B5 resulted in a sustainable value,
regardless of various fluctuating conditions. However, the sustainability of
B5 systems was right on the edge between sustainable and unsustainable.
The B5 system in Ha Noi became almost unsustainable when coproducts’
price decreases, and even turned into unsustainable when Hibiscus yield
increased. This response revealed that B5 systems were unstable and would
be in the danger zone when extreme conditions occurred. Furthermore, the