This document summarizes a research paper about converting municipal solid waste into bioenergy in the United States. It provides background on municipal solid waste generation and management in the US. It then discusses various technologies used to convert municipal solid waste into bioenergy, such as waste-to-energy plants, landfilling, composting, and anaerobic digestion. It also covers applications of these technologies and their costs and benefits. The conclusion discusses the prospects for further developing waste-to-energy conversion technologies.

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Municipal Solid Waste and Energy Production in the United States
Research Paper
By: Athbi Alasfour & Mohammed Alsharekh
Submitted to: Douglas D. Cortes, PhD
New Mexico State University, Spring 2015
04/30/2015

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Table of Contents
Abstract........................................................................................................................................... 3
Background..................................................................................................................................... 4
Conversion of Municipal Solid Waste to Bioenergy: Applications................................................ 9
Costs of Waste-to-Energy Conversion.......................................................................................... 15
Conclusion and Future Prospects.................................................................................................. 16
References..................................................................................................................................... 18

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Abstract
Municipal solid waste (MSW) is generated in large quantities throughout the United States. In
order to protect the environment, this waste must be disposed of safely, and recycled and reused
when possible. This paper describes the prevalence and diverse sources of MSW across the
United States, the means, along with principles, employed by United States and other countries
to treat MSW and produce renewable products, mainly bioenergy or biofuel, the costs and
benefits associated with waste-to-energy conversion, and future prospects of this application.

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Background
Municipal solid waste (MSW), typically known as garbage or trash in the United States
of America, is comprised of everyday items that are used and disposed on a daily basis by
everybody ((“Municipal Solid Waste, 2012”). These items include used packaging of products,
grass clippings from houses and institutions, bottles, old furniture, worn-out clothing, old
newspapers, used batteries, and food remnants among other things. There are multiple sources of
municipal solid waste, such as households, schools, hospitals, offices etc. The United States
Environmental Protection Agency (“Municipal Solid Waste, 2012”) is responsible for collecting,
keeping track of, disposing carefully, and recycling municipal solid waste all over the US.
Owing to the large population of the US, the Environmental Protection Agency (EPA) collects a
huge amount of trash; in 2012 alone, EPA recorded Americans disposing off roughly 251 million
tons of garbage. In the same year, EPA successfully recycled and composted nearly 87 million
tons of the municipal solid waste, thereby recycling as much as 35 percent of the total waste
deposited by the Americans across the majority of the states (“Municipal Solid Waste”, 2012).
Since the cost and effort required to recycle and discard off municipal weight is very
high, especially for a country as large and the US, the EPA encourages US citizens to adopt
practices which would decrease the quantity of waste generated. These efforts include waste
prevention, proper recycling, and composting. Waste prevention, also known as source
reduction, is aimed at producing products that would minimize waste, such as environmental-
friendly packaging, cloth grocery bags as opposed to plastic bags, and others; this not only
minimizes the overall municipal solid waste generated, but also ensures that the waste produced
is low in toxicity. Recycling, on the other hand, serves the purpose of processing waste material
for subsequent reuse; commonly recycled materials in the US include paper, glass, plastic, and
metals. Lastly, composting, also known as biological decomposition, refers to the process
whereby compost of made using organic waste products such as grass clippings, food remnants,
and manure, and adding bulk material to it such as wood chips; the resultant compost has a
plethora of diverse uses; a major proportion of the compost used in the US goes to the
agricultural sector, whereby it is utilized to remediate previously contaminated soil, increase crop
yield, diminish the use of chemical fertilizers, and to reduce the use of water and pesticides
(“Composting for Facilities Basics”, n.d.).

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The Environmental Protection Agency publishes several comprehensive statistical
reports, delineating the amount of waste generated annually, and the proportion of it that is
recovered for reuse by various processes. In 2012, for instance, the EPA recovered almost 70
percent old newspapers and 58 percent grass clippings or yard trimmings. Similarly, nearly 13%
plastics, 9 percent metal, 28 percent paper, 28 percent grass waste and food scraps, and 8 percent
rubber, textiles, and leather were recovered and reused (“Municipal Solid Waste”, 2012).
Overall, 86.6 million tons of municipal solid waste was prevented from being disposed, recycled,
and reused, as opposed to only 15 million tons in 1980 (“Municipal Solid Waste”, 2012). These
two stark figures are indicative of the advances in recycling and recovery techniques successfully
designed, implemented, and executed by the EPA in the US over the past decades. All of these
measures are a part of EPA’s Sustainable Materials Management Program (SMM), which strives
to protect the environment from harmful waste products, and conserve resources for the future
(“Municipal Solid Waste”, 2012).
The United States Environmental Protection Agency, and several other environmental
agencies, is coordinating with engineering companies to devise ingenious techniques that would
not only prevent the accumulation of MSW, but also extract beneficial uses from this waste. The
most promising use of MSW over the past decade has been its recycling, reuses, and conversion
to bioenergy and other renewable energy products. While this waste-to-energy conversion has
several disadvantages, its advantages clearly outweigh them. Over the next few years, it is
imperative that technologies and skills employed to convert MSW to bioenergy or biofuel be
developed further and their costs reduced, so that this process can be used at a wider scale across
the entire country. This may also serve as a useful model for other developed and developing
countries, since the problems associated with MSW treatment are ubiquitous.
Treatment of Municipal Solid Waste to Produce Bioenergy
Several diverse technologies have been devised and implemented in order to generate
energy using biomass. Over the years, these technologies have become more environment-
friendly and economical, thereby becoming more popular as well.

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As stated earlier, one of the main agendas of the Environmental Protection Agency in the
US in dealing with municipal solid waste is to reduce and reutilize it. Targeting the source and
not producing it in the first place can ideally reduce waste. Similarly, reusing municipal solid
waste, after appropriate processing, can prevent natural resources from being wasted; product
manufacturing typically requires many raw materials and energy sources, which can be
expensive, at the same time posing threats to the environment. Thus reuse can effectively get rid
of these issues by helping companies save money and conserving natural resources to benefit the
future generations. Briefly, reduction and reuse of solid waste can prevent pollution, save energy,
reduce harmful gas emissions that eventually lead to climate change, save money, and decrease
the amount of waste that must be recycled. Common practices for achieving waste reduction and
reuse include buying used products at lower prices, buying products that have less packaging or
eco-friendly packaging, consuming reusable products instead of disposable products,
maintaining the state of products such as clothes and furniture, and often renting or borrowing
items which you do not need permanently. All of these measures should ensure that the amount
of waste generated by households, schools, offices, and businesses are little and can be
efficaciously recycled or discarded (“Reducing and Reusing Basics”, n.d.).
Energy consumption is a major input in the manufacturing of a product, and municipal
solid waste can potentially be, and has been in the past, used for generating energy. Bioenergy,
or biofuel, is a renewable energy source that is associated with minimal greenhouse gas
emissions, lower footprint, and therefore a lesser impact on climate change. An estimation of
bioenergy potentials till 2050 using a variety of sources was carried out (Fischer and
Schrattenhoizer, 2001). There are several land categories, each yielding bioenergy inn different
forms. For instance, arable land is associated with crop residues, grassland with energy crops and
other kinds of biomass, forests with wood retrieved from forests and forest residues, and animal
waste and municipal solid waste (Fischer and Schrattenhoizer, 2001). Crop residues include
remains of crops, such as haulms of grain, stalks of sorghum, maize and millet, straw from
wheat, rice, barley and oat. The estimated bioenergy yield rates calculated were dependent on
various factors such as soil quality, water availability, overall climate of the region, and the crop
itself. It was observed that with the advancement in agricultural processes, the crop productivity
has increased and so have the bioenergy yield rates, though the bioenergy yield rates have not,
and are not projected to, increase at the same rate as the agricultural technology (Fischer and

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Schrattenhoizer, 2001). Similarly, bioenergy from land is dependent on many factors such as
land characteristic and the climate in the locality; radiation, temperature, soil moisture, terrain,
pests and diseases in the locality, water availability are all important in dictating the bioenergy
yield rates from arable land all over the world (Fischer and Schrattenhoizer, 2001). Lastly,
bioenergy produced from municipal solid waste is dependent on several variables such as the
amount of municipal solid waste generated annually by households, offices, and businesses; as
the population and per capita income increases, the amount of products bought and consumed,
and the amount of municipal solid waste generated, has increased exponentially over the past
years, especially in developing countries, thereby raising the bioenergy potential from this source
of waste (Fischer and Schrattenhoizer, 2001).
Several methods can be used for treatment of municipal solid waste, including landfilling,
composting, recycling, and mechanical-biological waste treatment (Psomopoulos and Themelis,
2009).In addition, waste-to-energy power plants are also being implemented and utilized, and are
operating in nearly 25 states in the US; these plants are fueled by municipal solid waste and are
known to generate up to 2700 MW of electricity in addition to recovering ferrous and non-
ferrous metals. Data suggests that waste-to-energy plants are highly efficient in energy
production; for example, they produce almost 600 kWh of electricity if 1 metric ton of municipal
solid waste is combusted in the plant. This implies that mining of a quarter ton of coal or
importing equivalent oil can be easily avoided (Psomopoulos and Themelis, 2009). Waste-to-
energy has been termed as biomass by the US department of energy, which implies that it utilizes
municipal solid waste that is primarily comprised of organic matter derived from plants and
animals such as human waste, crop remains, animal wastes, and feed crops; all of this waste
material is available on a renewable basis, hence the term biomass which constitutes 82% of the
combustible materials used in waste-to-energy power plants – the remaining 18% are usually
petrochemical waste products (Psomopoulos and Themelis, 2009). The ash resulting from waste-
to-energy power plants can be used in landfills as a covering, as a road base or construction
material, for mine remediation, or in agriculture owing to its distinct physical and chemical
properties which render it suitable for these applications (Millrath et al., 2012). Biomass is
comprised of carbohydrates and lignin. Biomass resources include agriculture and forestry
residues, energy crops such as sugar and oil, biomass processing wastes, and municipal solid
waste. Processes that convert biomass include densification, esterification, combustion,

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gasification, pyrolysis, fermentation or distillation, digestion, hydrolysis, digestion, combustion,
and gasification. These processes produce biofuels such as wood pellets, briquettes, biodiesel,
char or charcoal, fuel gas, bio oil, bioethanol, biogas, solvents, and refuse-derived fuel. The
renewable energy products these biomass resources can provide include heat energy, electricity,
and transport fuel (IEA Bioenergy, 2005).
Landfilling is one of the most economic means of disposing off municipal solid waste in
the US and across the globe (Fadel et al., 1995). When waste is first deposited at a landfill site,
the presence of oxygen leads to aerobic decomposition in which biodegradable materials such as
grass clipping and food remnants react with oxygen instantly to yield carbon dioxide, water, and
by-products; once the oxygen gas is depleted, anaerobic respiration is initiated, which dominates
the landfilling process. In the anaerobic step, organic materials such as solid human waste, food
scraps, grass clipping, cotton gin waste, etc. are converted to methane gas and carbon dioxide;
this conversion occurs in four steps, namely hydrolysis, acidogenesis, acetogenesis, and
methanogenesis (Fadel et al., 1995). While landfilling can produce energy using solid waste as
input, it has several disadvantages, which negatively impact the environment. These include gas
and leachate production at the landfill site, owing to microbial decomposition, climatic
conditions, characteristics of the refuse used as input, and operations at the landfill site. These
effects are highly dangerous because leachates, for instance, can become toxic to the methane
production process, also called methanogenesis, in landfilling especially in cases where both
industrial and domestic waste products are disposed of together. Other frequent impacts
associated with landfilling include fire and explosion hazards, damage of vegetation in the
vicinity, unpleasant odors that are long-lasting, landfill settlement, pollution of groundwater due
to leachate, air pollution due to production of other harmful gases in intermediate steps, and
global warming and associated temperature changes in the long run (Fadel et al., 1995). In
comparison to landfilling, the waste-to-energy power plants mentioned earlier are better in terms
of their environmental impact; they reduce the emission of greenhouse gases by approximately
26 million tons of carbon dioxide and do not produce volatile organic compounds and
chlorinated compounds, which are commonly produced in landfilling and deteriorate the
environment (Psomopoulos and Themelis, 2009). Despite their several benefits in comparison to
landfilling methods, however, waste-to-energy power plants have a few disadvantages.
Incineration, a part of waste-to-energy processes, at a large scale can have detrimental impacts

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on the surrounding soil, water, and air. Recently, however, the US has implemented air pollution
control systems wherever incinerators or waste-to-energy power plants are installed in order to
reduce the negative environmental impact they have.
Composting, as described earlier, is one of the procedures that turn solid waste into useful
energy. One application of this technique is the anaerobic digestion of cow manure and cotton
gin waste, forms of organic municipal solid waste,to yield methane gas; experimenters have
investigated the use of cotton gin waste and cow manure in various applications, such as energy
source, livestock feed, and soil amendment (Agblevor et al., 2003; Castleberryand Elam, 1998).
This utilization of municipal solid waste also stems from the increasing prices and diminishing
quantities of other sources of fuel, such as crude oil and natural gas. A comprehensive study of
the Texas High Plains, conducted by Wilde et al., shows a methodical approach used to utilize
cotton gin trash to produce bioenergy (2010). Briefly, the Texas High Plains are comprised of 30
counties, which collectively produce 64% of the total cotton in Texas, contributing a remarkable
22% to cotton production in the whole of US. By extension, this region is also one of the greatest
generators of cotton gin waste, and hence the predicted bioenergy that can be produced from this
region alone was studied in detail. Specifically, the Texas High Plains were reported to produce
994,736 tons of cotton gin waste between 2001 and 2006. Energy calculation revealed that 1 ton
of cotton gin waste produced by these plains could be translated to 76 mmBTUs of ethanol and
nearly 1.31 mmBTUs of electricity. Thus cotton gin waste is a very good source of bioenergy,
and in fact provides many benefits and solves many issues highlighted by the Environmental
Protection Agency.
Conversion of Municipal Solid Waste to Bioenergy: Applications
The applications of composting, used in the conversion of organic waste such as cow
manure and cotton gin waste to bioenergy or biofuel, rely on microbiological principles. Briefly,
the process is biooxidative in nature and involves mineralization and humification of the solid
waste, performed by microorganisms; the end product is a stable product which is much less
phytotoxic and relatively free of pathogens in comparison to the starting waste material (Bernal
and Moral, 2008).

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Another recent application of waste reduction, recycling, and reuse is the ingenious
machine that converts solid waste from sewage into pure water. The machine, commonly known
as the Janicki Omniprocessor, turns solid human waste into pure drinking water in a few
minutes. The machine is funded by the Gates Foundation and the design conjured and
implemented by the engineer Peter Janicki. It is intended to produce pure water from human
waste for as many as 783 million people across the world, people who do not have access to pure
water. The Omniprocessor essentially takes in solid human waste as input, boils it for a long time
period at high temperatures thereby separating the solid waste from the liquid portion; the water
vapor is separated from the solid waste and passed through a cleaning system which utilizes
cyclone and a plethora of ultrafine filters to remove pathogenic or toxic materials; ultimately,
condensation releases pure water than be drunk directly (NPR, 2015).
In the United Kingdom, a plant in the Westfield Development Centre in Scotland
produces energy from poultry litter using a fluidized bed combustion system that burns poultry
litter and converts it into renewable energy products, namely electricity and fertilizers (EPSU,
n.d.). Scotland’s Westfield’s region, where the poultry farming industry is very strong and
prevalent, is an ideal area for this sort of biomass processing and energy production; the poultry
litter, present in bulk quantities, is comprised of wood chips, straw, and poultry droppings. The
project is supported by the Scottish Environmental Protection Agency (SEPA) and is an epitome
of how municipal solid waste can be used to produce bioenergy to compensate for the
diminishing non-renewable energy resources and soaring prices of fuel from these other
resources (EPSU, n.d.). Production of energy from poultry litter is done via several processes,
including composting, anaerobic digestion, and direct combustion of poultry litter. Previous
attempts to use poultry litter as a source of bioenergy have proven quite successful. The biofuel
produced can be sold commercially to generate profits, especially in economies where the
poultry market is very extensive and hence poultry litter is prevalent; in these places,
technologies that convert poultry litter to biofuel are becoming more developed with the increase
in global technological advancement. This also ensures that the problem of poultry waste can be
not only addressed, but also be used to the benefit of the people (Kelleher et al., 2002).
A precise example of conversion of biomass to biofuel in the United States is the use of
switchgrass, also known as Panicum virgatum, as a bioenergy feedstock (McLaughlin and

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Kszos, 2004). The program that enabled this was supported by the US Department of Energy.
Briefly, switchgrass is a perennial grass grown primarily in warm seasons in the US. Several
studies indicated that switch grass could be grown for bioenergy production at a large scale. In
different regions across the US, different varieties of switchgrass are used for producing
bioenergy. Much of the bioenergy produced using switchgrass as the input biomass is done via
co-firing it with coal to generate electricity; in some cases, boilers may also be used
(“Switchgrass for Bioenergy”, 2013).. Research has indicated that switchgrass is an economical
source for producing bioenergy because it efficiently produces bioethanol; some projects have
investigated the production of butanol from switchgrass and coal co-firing (“Switchgrass for
Bioenergy”, 2013).While using switchgrass to produce bioenergy, the types and cultivars,
harvest times, site selection, plant growth, pest management and other factors must be taken
under consideration (“Switchgrass for Bioenergy”, 2013). Like switchgrass, other grasses and
remains of crops such as sorghum, rice, wheat, barley, and maize can also be used to produce
bioenergy, especially the parts which are not utilized as a food source so that the food utilization
is not compromised and the waste produced from remains of crops is disposed of properly, at the
same time yielding adventitious benefits of producing bioenergy and other renewable products.
In some regions in the US, pre-treated sewage wastewater, sewage sludge or slurry, and
methanogenic leachate produced as a by-product of landfilling have been used as inputs in short
rotation energy forestry for more than a decade (Hasselgren, 1998). In this process, the raw
materials or organic waste are used as fertilizers to boost forest growth, for example, at willow
plantations. This directly addresses the problem of scarcity of water and nutrients, as well as
costs associated with the purchase of fertilizers and implementation of irrigation channels. The
growth of willow plants, as a consequence of leachate or slurry application, was show to be
considerably stimulated due to the presence of heavy metals and trace organic compounds, which
are not phytotoxic, in the input fertilizer or biomass(Hasselgren, 1998).
Similarly, the utilization of biological and thermochemical conversion technologies to
convert livestock to bioenergy, or livestock waste-to-energy transformation, also yields
renewable products and helps recycle and reuse municipal solid waste. By using livestock
manure and feed to produce biofuel, or bioenergy, at a large scale on big farms, farmers can learn
to become less dependent on imported fossil fuels and can use the renewable products retrieved

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in improving the quality of the soil, water, and air on their farm area (Muller et al., 2007).
Furthermore, not only can livestock waste-to-energy help farmers get rid of municipal waste, but
it can also help them generate profit by selling the bioenergy and other renewable products
yielded by the process. Organic waste can be converted to biofuel using two efficient processes,
namely biological and thermochemical. Over the years, these two processes have seen ample
improvement in terms of reducing odor problems, utilizing by-products efficiently, reducing the
cost associated with the process, decreasing the harmful impacts on the nearby environment, and
recovering maximum energy from the livestock manure.
The underlying principle of almost all biological process is the presence of anaerobic,
aerobic, and photosynthetic microbes that produce useful, and infrequently harmful, gaseous
products and fuel. The biological conversion procedure is further divided into two routes:
fermentation and digestion. The former leads to the production of ethanol, whereas the latter
produces bio gas. In the market, this process can generate profits by selling ethanol in the
markets for chemicals and transport fuels, and bio gas in the market for transport fuels. Bio oil,
one of the major renewable products yielded by the biological waste-to-energy conversion
process, can be used as a fuel for transport vehicles, a common substitute for diesel and fuel oil,
and in boilers, turbines, furnaces, and engines for the generation of electricity (Czernik and
Bridgewater, 2004).
The thermochemical process, on the other hand, basically physically convert organic
manure to biofuel by using heat to break the bonds and transforming the municipal waste to
useful gaseous products, hydrocarbon fuels, and charcoal residual. The underlying basis of
thermochemical conversion of organic matter to biofuel is a high-temperature chemical process.
The benefit of this thermochemical process over other waste-to-energy conversions is that its
footprint on the environment in relatively small, the nutrient recovery is high, minimal fugitive
gases are emitted, the processing time is relatively short and hence the process is not very time-
consuming, a wide variety of livestock manure and feed canbe utilized as input, and the ultra
high temperatures ensure that any harmful pathogens are killed in the process (Centrell et al.,
2008). The thermochemical conversion of livestock manure and feed to bioenergy can be done
through four distinct routes: combustion, pyrolysis, direct liquefaction, and gasification. Each of
these routes yields different end- products and by-products. For instance, pyrolysis produces char

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or charcoal, bio oil, methane, carbon dioxide, and other minor gases. Direct liquefaction, on the
other hand, produces bio oil only. The products, furthermore, can be utilized in different
domains. For instance, char or charcoal is typically used in soil amendment, production of heat
and electrical energy, and bioenergy feedstock, whereas methane, carbon dioxide, and other
minor gases produced via gasification or pyrolysis can be used in bioenergy feedstock, and
turbine, engine, or boiler. Even more advantageous is the idea of integrating two or more
thermochemical processes to yield synergistic benefits. For instance, by combining drying,
pyrolysis, and gasification in a single thermochemical treatment process, it is possible to get
plenty of bio oil, char and charcoal, and other by products (Centrell et al., 2008). Overall, both
biological and thermochemical processes require biomass as input; the organic matter is then
subjected to fast pyrolysis or fermentation or anaerobic digestion, secondary processing, and
lastly tertiary processing. Each of these stages yields by products and other types of waste
products which can be used for distinct purposes. The end-products are chemicals, commodities,
and fuels (Czernik and Bridgewater, 2004).
One route combines biological and thermochemical conversion processes. Carbon
dioxide is emitted from both biological and thermochemical waste-to-energy processes and can
be harmful to the environment by contributing significantly to global warming (Usui and
Ikenouchi, 1997). Thus it is important to recover the carbon dioxide released and reduce the
short-term release by using algae, which fixes atmospheric carbon dioxide gas emitted by the
aforementioned process at a rate which is much faster than that of normal photosynthetic plants
(Usui and Ikenouchi, 1997). Algae can be used to generate algal biomass and oil within the cells;
these two useful products can be subsequently harvested and converted to useful value-added
products. Briefly, algae’s carbon dioxide-fixation efficiency is generally high, though it varies
from one type to another and depends on the atmospheric carbon dioxide concentration. The
production of biofuel via algae has several benefits over other biofuel-producing processes, such
as a rapid generation rate, a much greater yield of biomass, and successful waste treatment at a
large scale in both developed and developing countries. Net algal productivity has been
improved in the past few years by combining it with wet gasification (Cantrell et al., 2008).
Therefore, with the ever-increasing focus placed on renewable energy, the problem of
municipal solid waste and its clever utilization to produce bioenergy has been investigated

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deeply over the past decades. The use of municipal solid waste from households, offices, schools
and business to produce biofuel is one the rise in both developed and developing countries owing
to the worldwide shortage of other sources of non-renewable energy, such as coal and petroleum.
If carried out using correct safety measures, the production of biofuel from organic matter can
successfully reduce greenhouse gas emission and reduce problems related to global climate
change (IEA Bioenergy, 1998).
Thus overall, treatment of municipal solid waste treatment for reuse and recycling utilizes
several basic technologies, namely incineration, gasification, biogas generation, a combined heat
and power plant, biogas generation and conversion to useful biofuel. Each of these processes has
its own capital cost and gate fee; generally, in Ireland, the capital cost of treatment of the organic
matter component of municipal solid waste to produce biofuel for nearly one million people
using incineration is the greatest, amounting to almost 101,929,000 Euros, and for biogas to
transport fuel conversion is the least, amounting to almost 47, 522, 000 Euros (Murphy and
McKeough, 2004). The gate fee for each subcategory is more variable than the capital costs,
depending on several variables such as the number of people working, the current thermal
market, and theprevalent tax rate on transporting fuel produced via conversion of biomass among
other factors (Murphy and McKeough, 2004).
Bioenergy provides nearly 11% of the world’s total energy supplies (IEA Bioenergy,
2009). Since bioenergy is such an integral form of renewable fuel production, its markets have
been deeply analyzed recently. Biofuel is majorly used as fuel wood in non-commercial
applications, heating and cooking in households especially in developing countries, large-scale
industrial and community heat and electricity generation to some extent, especially where plenty
of municipal solid waste is present, and co-firing. Transport biofuels are also gaining popularity
with the every-increasing prices of other forms of fuel such as diesel and petroleum and shortage
of non-renewable energy resources. From a trading point of view, the biomass market is
booming; nowadays, both biomass feedstock, such as agricultural remains and wood chips, and
processed biofuel carriers, such as ethanol, biofuel, and wood pellets, are prevalently traded
internationally (IEA Bioenergy, 2009). Latin America and Sub-Saharan Africa have been labeled
as the primary exporters, and North America, Europe, and Asia as net importers (IEA Bioenergy,
2009). The biofuel market is dependent on many factors, like any other market, including

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competition between biofuel producers, economies of scale, public acceptance, and security of
the feedstock supply. The feedstock supply can vary considerably depending on the weather
conditions and seasonal changes in climate, thereby affecting the quantity, quality, and price of
the feedstock supply. Similarly, competition between bioenergy technologies and resources has
an impact on how many cost-effective bioenergy technologies are produced and how cheap they
are. Public acceptance has been identified asa big risk factor because regardless of the benefits
and development of biomass production, the public is still largely ignorant of its use as an
alternative energy source (IEA Bioenergy, 2009).
Costs of Waste-to-Energy Conversion
The conversion of organic matter from municipal solid waste to bioenergy, though
yielding multiple benefits, has a few costs associated with it. The process requires a large
quantity of waste, and while gathering waste such as food remnants, grass clippings, and cotton
gin waste might not be problematic, gathering poultry waste would only be restricted to areas
where poultry farming is carried out at a large scale. Moreover, transporting biomass to the
region where the plants or incinerators are located can be expensive because they need to be
supplied in bulk quantities and transport costs and generally high. Similarly, storing municipal
waste, such as poultry waste or livestock fuel, before it is used for processing and production of
biofuel can be expensive depending on the type of waste. Similarly, resources such as land and
water are typically limited; growing crops that are suitable for bioenergy production entails that
the land available for growing other crops is limited. With the current food crisis in many regions
of the world, it is imperative that the balance between growth of bioenergy and other crops is
maintained so that food availability is not threatened. Other losses incurred by overgrowth of
bioenergy crops include limited availability of housing land, threat posed on ecosystems, and a
greater rate of deforestation. Generally, countries which produce a lot of bioenergy substitute
other forms of fuel for this type of energy, and consequently, import less oil or petroleum; this
implies that the income source for these countries is reduced as fuel import duties are a major
proportion of earnings for governments (“Preliminary Assessment of Bioenergy Production in
the Caribbean”, 2009). Lastly, countries with no economies of scale in bioenergy production,
those that are starting out to produce bioenergy and have little prior experience, are at a

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disadvantage because for them, bioenergy production from municipal solid waste can be very
capital-intensive. Lastly, tariffs, trade barriers and subsidies also pose problems by impacting
market competitiveness among producers and distorting market prices (“Preliminary Assessment
of Bioenergy Production in the Caribbean”, 2009).
Conclusion and Future Prospects
In conclusion, municipal solid waste is produced in vast quantities across all states in the
United States of America. Recycling and reusing this waste is essential to address the issue of
discarding this waste because its presence can pose many problems, especially in developing
countries where there are no measures to get rid of municipal solid waste and the high population
entails that the waste generated is a lot. Municipal solid waste, therefore, must be discarded, and
the most common practice of discarding it safely includes recycling and reusing this waste
(Sefouhi et al., 2010). A common useful product that can be produced by treating municipal solid
waste using methods as diverse as composting, incineration, landfilling, fermentation, anaerobic
digestion, and waste-to-energy conversion in power plants is bioenergy or biofuel. As mentioned
earlier, the applications of conversion of municipal solid waste to bioenergy are diverse and its
implications are far-reaching. This phenomenon has previously been used in converting cotton
gin waste to bioenergy in the agricultural sector, converting poultry litter and livestock manure to
biofuel and, more recently, converting human waste to pure water. Therefore, it is essential that
the technologies employed in waste-to-energy conversion are explored and developed further so
that the costs associated with the process and its environmental impact, however little, can be
mitigated. In this manner, the benefits of extracting bioenergy from municipal solid waste can be
made to outweigh its disadvantages, and the process made more efficacious. Furthermore, this
application can address other global problems such as global climate change or global warming,
greenhouse gas emissions, increasing prices of non-renewable fuel resources, and depleting
resources such as crude oil, coal, and petroleum. In the US, the Environmental Protection
Agency (EPA) ensures that municipal solid waste is recycled and reused effectively so that waste
accumulation, which is very hazardous, can be prevented, and the extremely large quantities of
waste produced by households, offices, schools, and businesses, be appropriately processed or

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recycled and reused to cut costs, generate profits, advance environmental sustainability, conserve
resources, and lower the carbon footprint.
Therefore, although there are a few disadvantages of bioenergy production from
municipal solid waste, its advantages overrule them. By using biomass to produce biofuel, the
burden of treating large quantities of municipal solid waste can be decreased, and pollution of
land, groundwater, air, and freshwater can be mitigated. Bioenergy is an efficient alternative to
other forms of energy, providing a buffer or security measure for countries which can have the
capital and resources to convert biomass to bioenergy. The products of waste-to-energy
conversion can be used to increase agricultural productivity by increasing crop yields and
remediating soil to make it more suitable for crop growth. All of these measures can help
countries alleviate poverty and boost various job markets by providing employment to scores of
people in the bioenergy market. Moreover, many byproducts that arise from the conversion
process can be sold commercially and even exported if produced in large quantities at cheap
prices. By adopting mechanization and furthering investment in research of bioenergy production
methods and technological advancement, countries an easily increase the efficiency of biofuel
production.
In the future, bioenergy can be utilized at a greater scale if developed appropriately. To
benefit from bioenergy production using municipal solid waste, the US must strive to increase
biomass by adopting efficient, non-food bioenergy crops on lands which are not needed for
growth of food crops, and to establish sustainable biomass standards so that the methods
implemented are eco-friendly and do not have a negative impact on later generations.

18. 18
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