The Issue of Water Supply for Cultivation

Water supply for cultivation has becoming major issue in terms of growingly scarce in many countries as a result of increased competition with domestic or industrial uses. This issue could also contribute bad impacts of climate change in terms of reduced rainfall in some key producer regions which will place further pressure on local water supply. (Food and Agriculture Organization of the United Nations, 2008) Regarding the main topic, the production of biofuels requires water supply both in the expansion of the feedstock include the food crops such as corn, sugar cane, soy, oil palm and many more and also in the processing of the feedstock into biofuels.

In the 21st century, biofuels are currently own for about 100 km3 which is equivalent to 1 percent of all water that uses for crops worldwide. (Food and Agriculture Organization of the United Nations, 2008) Since most crops currently used for biofuels production, it needs a high consumptive of water to achieve the demand yield levels which best suited to high-rainfall topical areas. The table below depicts the water requirement for biofuel crops.

Water requirement for biofuel crops

Furthermore, water is required not only for the feedstock, but also for the production facilities especially in bio refineries. The facilities that produce biofuels require high-purity of water which is largely taken from the confined aquifer. (Pool, 2014) This can clearly place a further impact on unsustainable pumping taking place which eventually the future generation would not be able to use that aquifer. Moreover, the processing of feedstock into biofuels consists massive quantities of water, predominantly for cleaning plants and seeds. The loss of evaporation from cooling towers and evaporators during the distillation of ethanol and followed by fermentation could also contribute in high consumptive use of water. (Water implications of biofuels production in the United States, 2008) Hence, this will give greatest impact on local water resource balances.

According to Food and Agriculture

Organization of the United Nations (2008), the prospective for growth of irrigated areas could seem high in some sectors on the premise of water supply and land, the particular scope for increased biofuel production below irrigated conditions on existing or new irrigated lands is restricted by infrastructural necessities. This is to ensure water deliveries and by land-tenure systems that will not adjust with commercialized production systems. The figure 1 below depicts the potential for irrigated area expansion.

Producing more biofuels crops will affect the quality of water as well as the quantity. For instance, having pastures or woodlands converting into maize fields may aggravate the problems such as soil erosion, sedimentation and excess nutrient which is the usage of fertilizers. (Food and Agriculture Organization of the United Nations, 2008) Since fertilizers are require for crops in order for them to grow better, the downside of it which may contribute a harmful effects on surrounding and can cause contamination of water. This is due to the surplus nutrient (nitrogen and phosphorus) washed away from the soil into the surface waters and invade into groundwater. To compare with all the feedstock, maize is subject to the highest implementation rates of both fertilizer and pesticides per hectare. In Brazil, where primarily growth of sugar cane for biodiesel is associated with the utilization of fertilizers and agrochemicals, soil-erosion, sugar-cane washing and other methods are the major concerns. (Food and Agriculture Organization of the United Nations, 2008)

Lincoln Way Energy

Plant is one of the plant located in Nevada, United States produce conventional biofuels from food crops. It produces 50 million gallons of ethanol per year. They uses about 18 million bushels of corn and require around 150-200 million gallons of water each year. (Pool, 2014) To emphasize on the perspective of water use, the facility that produces 100 million gallons of ethanol per year will use around 300-400 million gallons of water each year, which approximately equivalent to what a town of 5,000 people uses. This results a very high consumptive of water for the feedstock together with production facilities.

In addition, biodiesel and ethanol production could also results in contaminated wastewater if it released untreated to the waterbodies which could increase eutrophication. These consequences on the quality of water can be treated with the wastewater treatment technologies which could deal effectively with organic pollutants and wastes. In the production facilities, the fermentation systems can decrease the biological oxygen demand of water by more than 90 percent which can reused for processing. (Food and Agriculture Organization of the United Nations, 2008) Methane that existed from the processing can be captured in the treatment system and utilize for power source. Therefore, the potential for negative impacts on soil and water from leakage and spills is reduced compared with the current resource which is fossil fuels.