Currently, the operation of the whole cultivation system is based on the electric
system. As a result, the energy consumption is indispensable. Increase or decrease
in energy consumption by 20% will lead to a 12.89% reduction or increase in ROI.
Compared to the aforementioned factors, however, total salaries and chemical
consumption do not strongly impact the cost. This is due to several reasons. Since
the cultivation system is highly automated, only restricted labor is necessary for
management and maintenance. It should be noted that nutrients like nitrogen and
phosphorus are derived from the municipal wastewater. Consequently, a certain
portion of the funds is protected as there is no need to buy extra nitrogen and
phosphorus, which also hints at efficient regulation of chemical consumption.
3.2 Algae-Derived Biodiesel
3.2.1 Cost and Revenue
Mostly, the economic cost is a manifestation of an amalgamation of material inputs,
labor, equipment repair and depreciation, and non-production inputs. It is assumed
that the project will be operative for 200 days annually and will last for 15 years,
according to Yang (2015). In summary, the first-year costs amount to USD 5246/
ton, which is the largest among the operation period. This is because several items
act as the first-year inputs. The average annual cost of the algae-derived biodiesel is
USD 3523/ton. Taking the byproduct revenue into consideration, the cost will
abruptly reduce to USD 960/ton.
In a similar fashion, the first-year structure is portrayed in Fig. 3. Material
inputs, including energy, land, water, nutrient, catalyst, dominate the total production cost per ton of the algae-derived diesel. The cost of material inputs is up to
USD 3415, corresponding to *65% of the total cost. Among the material inputs,
nutrients such as nitrogenous and phosphorus fertilizer yield the largest share,
Fig. 2 Sensitivity analysis for the algal ethanol production system
7 The Bioeconomy of Microalgal Biofuels
165
system. As a result, the energy consumption is indispensable. Increase or decrease
in energy consumption by 20% will lead to a 12.89% reduction or increase in ROI.
Compared to the aforementioned factors, however, total salaries and chemical
consumption do not strongly impact the cost. This is due to several reasons. Since
the cultivation system is highly automated, only restricted labor is necessary for
management and maintenance. It should be noted that nutrients like nitrogen and
phosphorus are derived from the municipal wastewater. Consequently, a certain
portion of the funds is protected as there is no need to buy extra nitrogen and
phosphorus, which also hints at efficient regulation of chemical consumption.
3.2 Algae-Derived Biodiesel
3.2.1 Cost and Revenue
Mostly, the economic cost is a manifestation of an amalgamation of material inputs,
labor, equipment repair and depreciation, and non-production inputs. It is assumed
that the project will be operative for 200 days annually and will last for 15 years,
according to Yang (2015). In summary, the first-year costs amount to USD 5246/
ton, which is the largest among the operation period. This is because several items
act as the first-year inputs. The average annual cost of the algae-derived biodiesel is
USD 3523/ton. Taking the byproduct revenue into consideration, the cost will
abruptly reduce to USD 960/ton.
In a similar fashion, the first-year structure is portrayed in Fig. 3. Material
inputs, including energy, land, water, nutrient, catalyst, dominate the total production cost per ton of the algae-derived diesel. The cost of material inputs is up to
USD 3415, corresponding to *65% of the total cost. Among the material inputs,
nutrients such as nitrogenous and phosphorus fertilizer yield the largest share,
Fig. 2 Sensitivity analysis for the algal ethanol production system
7 The Bioeconomy of Microalgal Biofuels
165