**2.1. Crop residues**

Apart from the grains of crops such as corn, wheat, and rice which as sourced for food, the remnants or left over from the processing of these grains also serve as an important resource. These residues generally makeup at least 50% by mass of the biomass in US grown crops. Over time, these resources have been sourced for animal bedding, combusted, or allowed to decay on farmlands. The recent development for use of the biomass residues for ethanl production or electricity generation sequel to scientific discovery has raised hope for the resource for both economical and environmental benefits. Significantly, the US agriculture can probably support up to 155 million tons of residues for producing bioenergy in 2030 [8]. Without the need of additional land requirement since these residues is by-product of major crops [16].

This resource is best used close to where livestock produces it, and would ideally be integrated with crop production. Crop residues do not usually appear in official statistics hence an estimate of the amount of crop residues produced are usually deduced based on production data [19, 20]. Available data for processing residues is generally poor, due to a wide variety of processing techniques producing an array of different stocks of residues [21, 22]. The ratio between main product and residue vary depending on a set of factors including variety, moisture content, nutrient supply, and use of chemical growth regulators among others. In reality, there are factors which limit the use of certain residues for bioenergy production such as scattered abundance, technical constraints, ecosystem functions, and other demands such as animal fodders, fertilizer, domestic heating, and cooking for which the application of the

Significance of Agricultural Residues in Sustainable Biofuel Development

http://dx.doi.org/10.5772/intechopen.78374

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Bentsen et al., presented a report relative to the production data of some crops which were combined with the residue-to-product ratios (RPR) of the different crops to obtain the amount of residues for each annual crop and from perennial plantation crops. The analysis showed that the estimated total amount of crop residue that is potentially available for energy was 150 million tonnes. Using 30% conversion that is typically obtained in biomass to energy conversion systems efficiency and the heating value data, these residues can generate about 0.60 EJ,

In accordance to the report of World Health Organization (WHO), United Nations Development Program (UNDP), 1.5 billion people, implying an estimated one-quarter of the world's population, do not have access to electricity [23]. In order to meet the UNDP millenium development goals, modern energy service need be supply to about two billion people. Lack of accessible and uninterrupted electricity supply and liquid transportation fuels undermines undeveloped and developing countries deleteriously, where population density is high and access to resources is low. About 2 billion people require on solid fuels (**Figure 1**), which are employed primarily for cooking and heating purposes. This development of combusting biomass environmental pollution and health issues. In the long run, the effect incurs health costs, where the main victims are the woman and children, due to the burning of solid fuels

Contrarily, developed nations sourced for bioenergy to combact the menace of environmental

crops with potential to generate high-yielding lignocellulosic biomass have been studied by [27]. Exploration of the special energy crops in developing countries may possibly displace food crops resulting in food-energy fued [28–30]. Food security, as well as energy provision from these crops, can be ensured when the degraded farmlands are used to grow crops after the

opportunities abound from dual cropping process, which can enhance agricultural productivity

by generating bioenergy from agricultural waste while food production is ensured.

emission and possibly reduce it and provide domestic energy [26]. Energy

emissions as a result of excessive land use [31]. Hence,

which is equivalent to 34% of the current energy consumed in Nigeria.

resource is being explored for.

**3. Bioenergy potentials**

in poorly ventilated housing [23–25].

deforestation, which can result in CO2

pollution due to CO2

Residues are known to offer a lot of advantages ranging from erosion prevention and mitigation against soil carbon depletion, their use for soil bioenergy production may adversely impact on these benefits, therefore, their utilization should be subject to certain circumstances, and even then, only at a predetermined magnitude. The amount of residues that can be collected is subjective and depends on several conditions relative to the farmland, this should be considered sustainably as removal of too much resdiues may cause exposure of the land to excessive erosion while too less or no removal of the residues can inadvertently prevent soils from drying in spring, thereby affect the planting season.

Removal of residues for bioenergy potential and application can impact negatively on other agricultural practices. The environment could be worsen as a result of excessive exposure of the farmland. In order to minimize the effect of this, farmers can employ various strategies to curb the effect. For instance they can use no-till farming and indulge in cover cropping to decrease soil erosion and water pollution. This will enhance agricultural production sufficiency while also provide abundantly the amount of residues for bioenergy biofuel production [17].

In corn-growing regions, large quantities of corn stover—leaves and stalks left over after corn is harvested—are available to produce ethanol. Corn residues are abundant near existing facilities fitted to produce and distribute ethanol made from corn grain. Indeed, companies are building the first three commercial-scale efforts to produce ethanol from agricultural residues near such existing facilities in Iowa and Kansas. Producing ethanol from corn grain and corn stover at the same location can reduce the use of natural gas and electricity by the combined facility, curbing the environmental footprint of the fuel [18].
