Energy as a Farm Product

Introduction

The world has and will always have an energy deficit despite all exertions to increase production. This situation is further exacerbated by the fact many valuable energy sources are being ruled out for various reasons (Holm-Neilsen et al, 2009). Coal for example is being faced out as a mass source of energy due to pollution concerns while one of the very reliable energy source; nuclear energy is now in doubt after the Fukushima Disaster. In a related development, the pollution and climate change debate has shifted focus to domestic animals’ waste as a major source of greenhouse gases (Holm-Neilsen et al, 2009). 

According to Herrero (2016), there are over 20 billion domestic animals in farms around the world supporting over 1.3 billion people directly or indirectly. This industry however, also produces up to 6 billion tons of greenhouse gases annually. The desire by the domestic farming industry to undo the damage occasioned by this greenhouse gas combines with the world’s desire for more energy as aforesaid to create the advent of energy as a farming product (Herrero, 2016). This research paper analysis the advent of energy produced as a farm product, the extent of production so far as well as future expectations from the sector, and the ensuing and anticipated challenges.

The science behind farm energy production

Whereas there are many forms of animal waste, this research limits itself specifically to manure. For the purposes of energy production, it is important to further categorize manure into two. Some farm animals are allowed to mix directly with farm products either in open ranches or enclosures that use fodder as bedding. The manure for this farm is, therefore, intermixed with plant elements that have not undergone animal digestion. This manure is referred as farmyard manure. One the other hand, when animal enclosures have concrete floor, the manure therefrom is pure animal produce mixed with water hence referred to as farm slurry or liquid manure. It is the latter form of manure that is used to produce biogas.

The research by Goswami et al. (2016) provides two major prerequisites of biogas. The first is that almost all organic materials can be transformed into biogas and the second is that currently only nature can produce biogas through the process of anaerobic digestion (Goswami et al., 2016). This is because biogas production is occasioned by microbes that contemporary science has been unable to culture including Proteobacteria, Chloroflexi, Firmicutes and Bacteroidetes. These make animals indispensable in the production of biogas. The main compounds found in biogas include methane, carbon dioxide, Hydrogen sulfide and other gaseous traces (Luo, Fotidis & Angelidaki, 2016). As energy source, biogas is highly combustible and is known to produce high amounts of heat with minimum pollution.

History of farm energy 

The article by Penn State University (2016) gives an extensive history of the understanding of anaerobic digestion as a process of turning organic substances into the combustible biogas. The author credits Jan Baptita Van Helmont with the discovery that anaerobic digestion produces biogas. In the 18th century, another scientist Count Alessandro Volta discovered that the amount of biogas produced was directly proportional to the amount of organic material introduced. Later in the 19th century, scientist Sir Humphry Davy attributed the combustive characteristic of biogas to methane gas (Penn State University, 2016).

With regard to the history of usage, biogas has mostly been utilized domestically as a source of cooking gas especially in the rural setting. The initial mass production of biogas can however, be traced to a leper village in Bombay in 1859 and in England in the late 1890s where biogas was being used for street lighting (Holm-Neilsen et al, 2009). 

Advantages of Biogas produced from manure

There are several material factors that make biogas produced using manure with the main advantage being cost effectiveness. Manure is a byproduct, not a main produce of domestic animals. Cattle is mainly reared for beef or dairy production while farm slurry is generally an unwanted by product from cattle farming. In this regard, slurry as a raw material for biogas can be considered as obtained free of charge (Luo, Fotidis, & Angelidaki, 2016). 

The second benefit of slurry biogas is production cost. There is no machinery or expensive chemical elements necessary for biogas production. Nature naturally produces biogas from farm slurry; all that is necessary is trapping and channeling paraphernalia. Further, there is no minimum level of production limitations like in some energy sources such as hydro-electricity (Luo, Fotidis, & Angelidaki, 2016). A small farmer can produce as little biogas as required in a family setup. Among the most important advantages of biogas production is the absence of pollutant byproducts. Indeed, by producing biogas from farm slurry, environmental pollution is reduced. 

Current scope of farm energy 

Millions of homesteads across the globe utilize biogas as a source of energy for domestic use such as cooking, lighting, and heating (Holm-Neilsen et al, 2009). The two most populous nations on earth are also the leading consumers of manure based biogas and many developing nations are also encouraging the domestic use of biogas as an alternative for wood based energy as a means of environmental conservation. Innovative products for domestic use such as biogas lamps, cookers, domestic biogas power generators and even biogas instant shower systems have heightened domestic use of manure biogas (Holm-Neilsen et al, 2009).

The advent of large scale cattle farming in many parts of the world have also led to the advent of large scale manure biogas production. Among the innovative systems for this includes the upflow anaerobic sludge blanket (UASB), the upflow anaerobic filter process (UAFP) and the anaerobic fluidized-bed reactor (AFBR). These processes have enabled the consistent production of high amounts of manure biogas. Storage of biogas has also been eased by the fact that it is capable of pressurization in a manner similar to liquid petroleum gas. Mass production and ease of storage has made it possible for industrial use of biogas such as production of electric energy to power industrial plants and also for massive industrial heating. 

Anticipated expansion in the industry

The first area of anticipated expansion is production efficiency. The research by Møller et al. (2006) looks into the possibility of generating more biogas per unit mass of manure available and analyses several innovative ways being developed in the Nordic republics to increase the efficacy of biogas production. Among the processes found to increase efficacy of biogas production include the pretreatment of hydrolysis of the lignocelluloses structure of manure fibers. This was seen to greatly improve biogas production from the same amount of manure (Moller et al, 2006). 

From a different perspective, another efficacy increasing procedure used was separating the parts of manure that produced most biogas. This would create a form of concentrated manure that would automatically yield more gas per unit area. Separation as aforesaid would be ideal for mass production as the holding tanks for manure would be more efficiently utilized.

The second anticipated growth in the industry is the increased use of biogas production as a means of reducing greenhouse gas production from animal farming. Gilroyed et al. (2010) conducted a research premised on the understanding that the contents of the plant derivatives fed to the animals influenced the amounts of greenhouse gas emitted by the animals. The research therefore envisaged the process of co-digestion. Through this process, elements used to make fertilizer are digested through the process of biogas production and compounds that increase eventual greenhouse gas production are gotten rid of. This will make biogas production an integral part of cattle farming and consequently increase efficiency as biogas production will have two products, improved fertilizer and biogas itself (Gilroyed, Li, Hao, Chu, & McAllister, 2010).

Another anticipated change in the future of biogas is transformation to mainstream use. This includes use for mass production of electricity enough to be incorporated in the national grid and this is the basis for the research reported in Molino et al. (2013). For electricity to be included on the main power grid, it must be in high quantity and produced consistently. These are some of the issues being refined and researched as the world shifts towards clean energy production.

The other anticipated use of biogas energy is for the propulsion of motor vehicles. Currently, the overwhelming majority of motor vehicles make use of environmentally unfriendly fossil fuels. Increased research including Börjesson et al. (2015) shows a great potential for biogas as an alternative environmental friendly motor vehicle fuel. The upshot of the foregoing is that there is a great future in manure biogas production and usage and it is even envisaged that in the near future, manure might become a primary product for cattle rearing as opposed to a byproduct. Cattle might actually be rared specifically for biogas production.

Present and future challenges

One of the biggest current and future challenges of manure based biogas is its natural production method. Man is a dominant being who prefers having overall control. The production of biogas however, is based on organisms that have so far proven uncontrollable (Insam et al, 2015). This is a handicap that can only be worked around. Research on the microbes that transform organic matter has proven to be complex and expensive. Another major challenge for manure based biogas is the fear of its future potential. In the US as well as the world at large, energy is one of the largest industries in the world. Many energy investments cost billions of dollars and have an anticipated return spanning over decades. This has created a great opposition to biogas as an industry. 

The opposition has also resulted in a lot of research designed to show that biogas has more negative than positive attributes. The research by Styles et al. (2015) shows an in-depth research on many a negative attribute for biogas (Styles et al, 2015). This includes showing that the processes of co-digestion and use of manure for biogas and as a fertilizer hurts the environment. These findings have also been supported by another recent research reported by Pivato et al. (2016). This research seeks to confirm that fertilizers produced through co-digestion are toxic to the soil. 

Conclusion

The upshot of the foregoing is that manure based biogas has been an essential source of energy for small scale use for a long time. With the advent of big cattle farms, animal manure is being produced in much larger scale. The cattle farming industry has however, been accused of massive air pollution through greenhouse gases emission. Further, energy needs continue to increase in the world due to population increase and industrial expansions and these factors make manure based biogas an important and indeed essential source of energy from a small scale to a large scale scope. The current trend of research and actual biogas mass production has shown great potential and more needs to be done for this industry to reach fruition. However, as with all nascent industries, there is a lot of opposition from mainstream energy producers, but the positives attributes of the industry will clearly overcome these hurdles.

References

Börjesson, P., Prade, T., Lantz, M., & Björnsson, L. (2015). Energy crop-based biogas as vehicle fuel—the impact of crop selection on energy efficiency and greenhouse gas performance.  Energies ,  8 (6), 6033-6058. 

Gilroyed, B. H., Li, C., Hao, X., Chu, A., & McAllister, T. A. (2010). Biohydrogen production from specified risk materials co-digested with cattle manure.  International Journal of Hydrogen Energy , 35 (3), 1099–1105. doi:10.1016/j.ijhydene.2009.11.072 

Goswami, R., Chattopadhyay, P., Shome, A., Banerjee, S. N., Chakraborty, A. K., Mathew, A. K., & Chaudhury, S. (2016). An overview of physico-chemical mechanisms of biogas production by microbial communities: A step towards sustainable waste management. 3 Biotech , 6 (1), 72. doi: 10.1007/s13205-016-0395-9.

Herrero, M. (2016).  To reduce greenhouse gases from cows and sheep, we need to look at the big picture . Retrieved from <http://theconversation.com/to-reduce-greenhouse-gases-from-cows-and-sheep-we-need-to-look-at-the-big-picture-56509/> 

Holm-Nielsen, J. B., Al Seadi, T., & Oleskowicz-Popiel, P. (2009). The future of anaerobic digestion and biogas utilization.  Bioresource technology , 100 (22), 5478-5484. 

Insam, H., Gómez-Brandón, M., & Ascher, J. (2015). Manure-based biogas fermentation residues–Friend or foe of soil fertility?  Soil Biology and Biochemistry ,  84 , 1-14. 

Luo, G., Fotidis, I. A., & Angelidaki, I. (2016). Comparative analysis of taxonomic, functional, and metabolic patterns of microbiomes from 14 full-scale biogas reactors by metagenomic sequencing and radioisotopic analysis.  Biotechnology for biofuels ,  9 (1), 1. 

Molino, A., Migliori, M., Ding, Y., Bikson, B., Giordano, G., & Braccio, G. (2013). Biogas upgrading via membrane process: Modelling of pilot plant scale and the end uses for the grid injection.  Fuel ,  107 , 585–592. doi:10.1016/j.fuel.2012.10.058 

Møller, H. B. , Nielsen, A. M., Andersen, G. H., & Nakakubo, R. (2006).  Process performance of biogas plants integrating pre-separation of manure . In  Proc. Technology for Recycling of Manure and Organic Residues in a Whole-Farm Perspective 123 (2), 125-128.

Pivato, A., Vanin, S., Raga, R., Lavagnolo, M. C., Barausse, A., Rieple, A., & Cossu, R. (2016). Use of digestate from a decentralized on-farm biogas plant as fertilizer in soils: An ecotoxicological study for future indicators in risk and life cycle assessment.  Waste Management ,  49 , 378-389. 

Penn State University. (2016).  A short history of anaerobic digestion (Biogas and anaerobic digestion) . Retrieved from <http://extension.psu.edu/natural-resources/energy/waste-to-energy/resources/biogas/links/history-of-anaerobic-digestion/a-short-history-of-anaerobic-digestion/> 

Styles, D., Gibbons, J., Williams, A. P., Stichnothe, H., Chadwick, D. R., & Healey, J. R. (2015). Cattle feed or bioenergy? Consequential life cycle assessment of biogas feedstock options on dairy farms.  GCB Bioenergy , 7 (5), 1034-1049