Greenhouse Gas Emissions From Water Production: An Essay.

Prepare a report on the topic on Greenhouse Gas Emissions Associated with Water Production. 

Greenhouse Gas Emissions and Environmental Impact

Greenhouse gases are the ones that trap heat in the atmosphere. The greenhouse gases allow the sun's heat to enter into the atmosphere and unhindered as a shortwave energy. This heats up the surface of the earth and the same energy is re-radiated in the form of longwave energy into the atmosphere which is absorbed by these greenhouse gases. This results in trapping of the heat energy in the lower atmosphere. There are many greenhouse gases that occur in the atmosphere, such as nitrous oxide, water vapour, methane and carbon dioxide, where there are other gases that are synthetic. There are other gases that are man-made and like the chlorofluorocarbons, Sulphur hexafluoride, perfluorocarbons, and hydrofluorocarbons. The water utility practices are closely associated with the activities of greenhouse gas emissions (Morris,Paltsev& Reilly, 2012). Water management is required to meet the increasing demand for the change in climate and in several of the cases results in the additional energy usage. There are several regulations in the USA regarding the monitoring of the greenhouse gas emissions but there exists a gap between the energy and the water management. Energy and water are closely linked and this is called as the energy-water nexus, the term captures the aspects of the energy and water interaction. Water is a very important component of energy production and this includes the fossil fuel extraction like biofuels, hydroelectric power and cooling. At the same time, the energy produced is used for treating, supplying and using water. The rise in the levels of the greenhouse gases and the environmental impacts is associated with the various changes in the environment like the severe heat waves, acid rain, drought and intense weather conditions (Samimi&Zarinabadi, 2012).

Greenhouse gases have got severe environmental impacts on the environment due to climate change associated with it. Rise in temperature due to increase in the GHGs in the atmosphere often results to various changes on the planet earth. It can result to drought leading to lack of water, intense rain which is acidic as well as severe heat waves. Additionally, there can be melting of the ice and glacier leading to the rice of ocean levels causing tsunami. All this have got negative impacts to both human society as well as environment. GHGs gases do not only have harmful effects on human health but also on the climate (Williams et al, 2014). Due to the high trap-ability of the GHGs gases, there continuous production increases warming of the earth leads to increase in the emergence of diseases, deaths and extinction of various organism.

Additionally, increases GHGs gases leads to the reduction of the fresh water for consumption depletion of ozone layer. According to WHO, consumption of water that is contaminated by the GHGs can leads to irritation of the respiratory system causing respiratory problems, reduction functioning of the lungs and aggregate asthma as well as impairment of the body system of defence. Additionally, environment impacts include reduction in the growth rate, increases susceptibility of plant to diseases, injury and premature mortality of plant tissues as well as reduce survivability of the plants. Therefore, there is need to use safe and clean energy for use in transportation, electricity and production of water (Searchinger et al, 2012). The emissions from the water utilities when evaluated showed that various activities have led to the emission of nitrous oxide, methane and carbon dioxide. The greenhouse gases are produced from the mobile combustion and onsite combustion and the emission are caused due to the usage of chilled and hot water by the water utility, production of steam and electricity (Anthony & Tanju Karanfil, 2013).

Greenhouse Gas Emissions from Water Utilities

The purpose of the study is to is to estimate the Greenhouse gas emissions of the Tampa Bay Water operations in the production and supply of water to their customers. The Study will focus on addressing the research questions posed by TBW to assess their methods of estimating GHG emissions form their operations. The significance of the project is to ensure that methodology used by the TBW is accurate. The scope of the study is mainly emphasising on the TBW and its operations that are based on the environmental protection agency data. It has been found that the TBW has started maintaining sustainable energy management systems and strives to accurately estimate the amount of the greenhouse emissions that are associated with the water production.

Since the year 1990, a steady increase has been noticed in the emission of the greenhouse gas. In the year 1990, the United States experienced an increase in greenhouse gas by 2 percent (US EPA, 2018). Due to certain changes in the economy, fuel process and other factors the level of the emission increases in a year. Greenhouse gases occur naturally and the increase in the concentration of the gases increases due to the anthropogenic activities (Shailesh, 2013). Freshwater is essential not only for human survival but also for the drinking and other activities like the farming. It has been indicated by Huang and Chen (2017) that supply of water is going to reduce in the near future due to the increased effect of greenhouse gases. The problem of water scarcity starts by taking into consideration the distribution of water on the earth. Studies have indicated that the 98 percent of water is salty and thus only 2 percent of water is available for human consumption and for other uses. It is, however, important to note that of the 2 percent, 70 percent exists in the form of glaciers and ice. Of the 2 percent, only 30 percent of water is groundwater and 0.5 percent of water is surface water which is found in lakes and rivers. Additionally, only 0.5 percent of water is available in the atmosphere. Researches have shown that the due to the increase in temperature caused by the increased levels of greenhouse gases cause global warming and this leads to the melting of polar ice caps. The melting of the polar ice caps has led to an increase in the sea level and it has effects on the water supply (Heller et al., 2018). A study conducted by the Environmental Protection Agency (EPA) indicated the fact that greenhouse gases like the nitrous oxide and methane are they are highly soluble in water and this can be detrimental for the human consumption (Huang & Chen, 2017). The atmospheric lifetime of the greenhouse gases that are produced by the different industries varies and gases like carbon dioxide have a lifetime ranging from 50 to 200 years. Methane has a lifetime of about 12 years and nitrous oxide has a lifetime of 114 years. The greenhouse gases like methane and nitrous oxide have the heat-trapping capability and both methane and nitrous oxide are the potent greenhouse gases that can increase the atmospheric temperature to a great extent. This has a negative impact on the stratosphere, biosphere, atmosphere and hydrosphere. Thus, there is an urgent need of clean energy at the affordable rates that can substitute the fossil fuel and ensure the protection of the environment (Zhou, 2014).

Methodology for Estimating Greenhouse Gas Emissions in Tampa Bay

TBW has developed an internal greenhouse gas calculator that is based on the billing data for the purpose of water production which specifically includes pumping of water. Energy data from the Energy Consumption Manager is disaggregated by the sources like the Withlacoochee River Electric Cooperative, Duke and TECO. From the data, the kWh/MGal pumped was calculated at the various facilities. TBW utilized the emission factors sourced from EPA to estimate the greenhouse gas emissions data in tons or pounds/kWh for the different sources of energy. In order to estimate the reduction in the greenhouse emission from the operations, TBW used information from the water conservation reports that were used in estimating the reduction in pumping energy. The three main water reduction activities include the reduction in the amount of the hot water usage in the residential buildings and commercial pre-rinse spray, water conservation activities or the source substitution (reclaimed water).

This proposal will assess the methodology used to estimate the GHG calculation and the emission factors applied and compare them against practices used elsewhere. Based on the assessment, the research may develop some recommendations to improve the methods of GHG estimation. The study is based on evaluating the different calculation procedures employed by TBW in the reduction of the greenhouse gases due to water production.

Greenhouse gases are the main reason due to which the global warming has increased to a large extent and it has led to several undesirable changes in the atmosphere and has also led to the steady decline of the species. Due to the ill effects of greenhouse gases, both the human society and the environment are negatively affected and thus there is a need to develop the mechanisms to control the impacts. This research will highlight the method employed by the TBW in the greenhouse gas emission. The study will assess if the standardized or the average could be used if the data of electric consumption is not available from the local sources. For example, if the data from the energy sources are not available in time then the average or the standardized data can be used. The main objective of the study is to carefully assess the greenhouse calculations that are made by the TBW and also to evaluate the methodology in comparison to the commonly used greenhouse gas calculation. The evaluation procedures will also include the assumptions made, the emissions factors that are used in the calculation, the greenhouse gas calculations from other places and suggest recommendations for the TBW calculator. The study aims to evaluate the impact of the greenhouse gases on the climate over a period of time; to examine the greenhouse gases that are associated with the production of water; to develop the methodologies that can be used in the calculation of the greenhouse gas emission that is associated with the energy use during the production of water.

This study will examine the following questions:

• Are the methods for creating kWh used per production point being transformed correctly?
• Are the methods for determining GHG emissions per electricity used at sites being calculated correctly?
• What standardized or averaging could be used if electric consumption data isn't available from local sources (For example the TECO data did not get processed in time for TBW to use for 2017).
• What can alternative (standard) GHG emissions data be substituted for EPA emission factors if they are not up to date?

The prime scope of the research is to analyse the greenhouse gas which is emitted during the activities like the water production, electricity generation as well as the transportation sector. The main area where the research will be carried out will be the TBW. The production of the various gases like the nitrous oxide, methane and carbon dioxide will be highlighted and the project will take a maximum of three months. The scope of the study is to assess the methodologies employed by TBW in evaluating and estimating the greenhouse gas emission from its water-related activities. The study, on the other hand, will not include any discussion on the integration of methods of greenhouse gas reduction.

Water Production and Greenhouse Gas Emissions

The highlights the emissions from steam, electricity, and other sources of energy that are used by the energy. The scope 3 indicates the various consequences that have occurred due to the excessive operations from the different sources in an organization. Here, different resources have been introduced in the case to analyse the different greenhouse gas sources. Logistics and business travel, third-party distribution and employee commuting are included within these sources. The study also mentions the emission from the production of purchased goods, emission from the sold products and many more sources of greenhouse gas

Green House Effect:

Green House Effect implies physical properties of nature that allow trapping thermal emission within a stipulated zone. The intensity of this natural phenomenon depends on the layer that traps the thermal emission by blocking the penetration of the energy high wavelength (Arslan, Cigdemoglu& Moseley, 2012). However, the term Green House comes from an agricultural technique that allows trapping the thermal radiation within a glass-covered area situated in an extremely cold atmosphere for agricultural purpose. The major reason behind this natural phenomenon is the penetration of thermal energy and its cardinality with the wavelength. When initially the light wave coming from an external source penetrates the greenhouse cover layer, it has very high frequency and small wavelength. According to Varma and Linn (2012), after the absorption, the wave loses the energy and decreases its frequency that resultantly increases its wavelength (V=f*l, where v is the speed of the wave, f is the frequency and l is the wavelength). Now the wave with high wavelength becomes unable to be free by penetrating the greenhouse layer that enables the greenhouse to trap the thermal energy within it. As a result, the temperature becomes increased. As per Cook et al., (2013), the atmosphere of earth acts same as this greenhouse effect that allows sustaining the surface temperature at 15⁰ C. Without this atmospheric greenhouse effect the surface temperature of the earth would be -18⁰ C.    

The reason behind the greenhouse effect of the earth atmosphere is the presence of certain gases such as Carbon dioxide (CO₂), Methane (CH₄), Chlorofluorocarbon (CFC), Water vapour (H₂O), Nitrous oxide (N₂O), Ozone (O₃) and Hydrofluorocarbons (Ma et al., 2013). The basic principle to be a greenhouse gas is having more than one or two atoms in a molecule that can successfully trap the infrared wave within the atmosphere. Non-greenhouse gases such as Nitrogen (N₂), Oxygen (O₂), Argon (Ar) are not greenhouse gas due to their molecular structure featured by only one or two atoms of the same element to build the molecule. This physical feature does not enable them to absorb infrared or react against the vibration. However, gases like Carbon monoxide (CO), Hydrogen Chloride (HCL) absorb the infrared because of the presence of atoms from an individual element in the molecule. As opined by Zhang et al. (2012), this molecular structure allows them to block the high wavelength wave to penetrate through them. However, these gases are very unstable in the atmosphere because of their high reactivity and solubility. Apart from that, some gases have an indirect radiative effect that causes due to their chemical reaction with other gases in the atmosphere. As an example, CO or carbon monoxide is a weak greenhouse gas that traps only the IR (Infrared) at shorter wavelength because of their single vibrational band (West et al., 2013). However, CO gets oxidized in presence of water vapour and becomes CO₂ that is a strong greenhouse gas. On the other hand, both carbon monoxide and Methane reacts with OH radicals and makes a reversible cycle reaction causing an indirect greenhouse effect. At the same time, destruction of non-methane volatile organic compounds (NMVOCs) in the atmosphere can produce Ozone, which is a good greenhouse gas (Harvey, 2016).

Need for Clean Energy

Water is not directly involved in generating greenhouse gas emission while there is an indirect impact of water utilization on overall greenhouse emotion in our atmosphere. As per Rosa and Dietz (2012), the water processing lifecycle causes more than 15% of greenhouse gas emotion in which 10% is emitted indirectly through the utilization of electrical power and other machinery utilization. To understand the role of water utilities in Greenhouse Gas emission the understanding of water process life cycle is essential. Initially, the water is pumped out from different natural and artificial water resources that consume a high amount of electricity. The clean water then distributed to the residential, agricultural and industrial area. The usage of water causes liquid waste, which is collected by a pumping system that again consumes a high amount of electricity (Arslan, Cigdemoglu& Moseley, 2012). Then the wastewater recycling treatment purifies the wastewater into the clean consumable water. This treatment procedure consumes electricity while during the water treatment a large amount of greenhouse gas like carbon dioxide, Nitrous oxide, methane and other are emitted. Apart from the when the water used for an agricultural purpose it produces greenhouse gas like Methane. The electrical consumption throughout the water process cycle is significantly high. To produce this amount of electricity the power plants produce a large amount of Carbon dioxide and other strong greenhouse gas (Fearnside&Pueyo, 2012). Apart from that, from the initial pumping and storing to final recycling the equipment, which are used for executing the procedure, emit a huge amount of greenhouse gases like carbon dioxide, carbon monoxide, Chlorofluorocarbon and others. However, the methane produced from the agricultural operation is not controllable, while the other part of the after cycle can be altered to reduce the greenhouse gas emission.

According to Anderson, Hawkins and Jones, (2016), the water and wastewater industry uses 4% of the total domestically electricity produced in the United States. This huge amount of energy consumption has made the wastewater industry one of the highest electricity consuming industries in The United States. On the other hand, the required energy to produce potable water is increased because of the degrading source ware quality and changing regulations that need more electricity consuming techniques. The Life Cycle Assessment studied covering the three areas of discussion namely the emission from the operational state of utility lifecycle which is the leading contributor of greenhouse gases indirectly, the utility of equipment in operational phases and during the chemical process in treatment plant (Zhang et al., 2012). Throughout the process, the treatment use is the only direct producer of the GHG as well as the second largest source of environmental impact. Throughout the process, the consumed electrical power is generated by emitting 31 million metric ton of carbon dioxide equivalent (Co2-eq). Among many other public service operations, water processing causes 31% of GHG emission (Bolaji&Huan, 2013). At the same time, the change in climate has a huge impact on the natural sources of water considering both underground and surface water on the planet. The changed chemical factors in natural water sources require additional treatment and recycling procedure consuming a huge amount of additional power while emitting a considerable amount of greenhouse gas.

Background

As discussed earlier the water pumping and recycling or treatment procedure requires a huge amount of electricity. To reduce the electrical consumption, identification of major procedures that consume the majority of the electricity is essential (Zhang et al., 2012). As per the report of Electrical Power Research Institute or EPRI from 1997 to 2000 the average energy use was 1.6 KWh per 1000 gallon of water. However, from 2010 the consumption of the average energy for 1000 gallon of water has been increased and has become 1.9 KWh per 1000 gallon. This increased level of consumption has increased the utilization of fossil fuel and emission of GHG in power plants. In the treatment procedure, only the Ozone Disinfection process causes 0.4 kWh per 1000 gallon energy consumption (Drake, 2014). The table 1 (appendix) describes the required energy for water process cycle

The emission inventory is a process of measuring the existing and possible level of emission while determining the appropriate scopes to resist such occurrence. The inventory method of Greenhouse Gas is mainly regulated by the IPCC format by the United Framework Convention on Climate Change or UNFCC (Fearnside&Pueyo, 2012). The method of inventory covers the GHG emission because of the combustion activities as well as the transport, manufacturing and construction industries. The combustion activities refer to the mechanical activities that use fossil fuel to generate adequate energy. The Combustion process executed in both industrial and residential area; however, the amount of emission from these two sources is different. While it comes to determining the emission due to transport, the emission from the military operation, aviation industry, rail, vehicle transport and water transport are considered as the major sources. As opined by  Hamit-Haggar (2012), Apart from mentioned causes, technical faults, leakages, evaporation loss, ventilation, flaring and accidental emission cause additional emission of greenhouse gases, especially, carbon dioxide, carbon monoxide and others.

The purpose of Inventory of GHG reflects the process of execution of it, which are described below:

• Determination of the goal and the purpose of the inventory process conceding the inventory information and target audience
• Determination of the boundary and metrics of the existing as well as potential measurement procedure considering both the direct and indirect emission
• Data collection, analysis to identify, and keeping record the numerical representation of several parameters associated with Greenhouse Gas  
• Numerical and statistical analysis of Greenhouse Gas quantities and convention to carbon dioxide and its equivalents depending on the Global Warming Potential (GWP)(Bolaji&Huan, 2013)
• Interpreting the outcomes from the inventory method considering the percentage of changing in Greenhouse Gas

Greenhouse Gas Inventories can be understood as a form of emission inventory. The inventory includes both natural as well as anthropogenic emissions which can be used to develop atmospheric models (USEPA, E, 2015). These models can then be used by policymakers to make strategies and policies that can reduce the emissions and also track the progress of the policies or strategies. Apart from the sources of emissions, the greenhouse gas inventories also include carbon skinks which are associated with the removal or sequestering of carbon from the atmosphere (Subramanian et al., 2015)

The United States Environmental Protection Agency (USEPA) prepares a yearly report known as the Inventory of US Greenhouse Gas Emissions and Sinks (inventory) which helps to track the greenhouse gas emission by the US classified on the basis of their sources, economic sectors and greenhouse gases liberated, thereby providing a comprehensive account of all human-created emissions of greenhouse gases (such as carbon dioxide, methane, nitrous oxide, hydrofluorocarbons, sulfur hexafluoride, perfluorocarbons and nitrogen trifluoride) (Heede, 2014). Specific protocols and guidelines exist for creating Greenhouse Gas Emission Inventories (Janssens-Maenhout et al., 2015). The EPA uses 4 such categories, namely:

Problem Statement

This provides the guidelines for creating inventory for the emissions of GHG such as methane, carbon dioxide and nitrous oxide from stationary or non-transport combustion sources such as dryers, boilers, heaters, kilns, thermal oxidizers, furnaces, ovens, or any devices that are used for the combustion of carbon-rich fuels (such as biomass) or waste materials (or waste-derived fuels) and helps in the calculation of greenhouse gas emissions from these sources (Marchese et al., 2015)

Direct assessment and evaluation of input Fuel.  For direct assessment, the Continuous Emissions Monitoring System (CEMS) Method is used which measures the pollutants liberated into the air from the exhaust of industrial sectors and combustions (Sloan, 2014). The Fuel Analysis Method is another way to calculate the emissions of carbon dioxide using information specific to the fuel or default emission factors (epa.gov, 2018a).

This provides the guidelines for the creation of an inventory of greenhouse gas emissions from the combustion of fuels in various categories of combustion engines or mobile devices. Categories of sources include On-Road Vehicles, Non-Road Vehicles, Waterborne Vehicles, Rails and Air Vehicles. The Greenhouse Gas emission is calculated separately for carbon dioxide and for methane and nitrous oxides (Lamb et al., 2015). It utilizes separate sets of equations for the calculation of each type of emission. The steps for calculating the emission is step 1: Selecting the proper equation developed on the type of fuel used. Step 2: Determining the amount of fuel used in the combustion. Step 3: Determining the equation inputs which are needed to calculate the emissions and Step 4: Calculating the emissions using the proper equation with the consumption of fuel and other inputs in the equation. The accuracy of the calculations is increased by incorporating specific information for each vehicle such as fuel type, fuel usage, distance travelled, economy, type of vehicle and technology for controlling emissions (epa.gov, 2018b).

This provides guidelines for the creation of emission inventory for emissions from the various processes in an organization but is mainly given off from by sources owned by other organizations and is thus considered ‘indirect emissions' (Ji et al., 2016). These indirect sources include usage of electricity, steam, heat or cooling systems that are delivered to an organization from independent entities, localized grids or district energy systems through direct connections to the organizations using these energies. Greenhouse gases are produced to create power and heat which are then supplied to the consumer organizations. The emissions produced depend upon the type of power used to produce the energy and the guidelines provide a method to calculate such emissions. The calculation is done by determining the amount of energy purchased, determining the emission factors and then calculating the emissions (epa.gov, 2018c).

This helps to calculate ‘fugitive emissions’ from different types of emissions and processes such as fire suppression, air conditioning, refrigeration and buying and selling of industrial gases (Cristofanelli et al., 2018). The greenhouse gases usually measured in this method include Chlorofluorocarbons (CFC), hydrofluorocarbons (HFC) and other ozone-depleting substances. The guidelines addresses specific aspects such as the emissions from the users of air conditioning equipments and refrigeration systems (such as domestic and household systems, chillers, heat pumps, mobile air conditioning systems, refrigerated transports, retail food refrigeration, cold storage warehouses, industrial refrigeration systems and commercial systems), emissions from portable or fixed fire suppression systems and direct emissions from purchased industrial gases (Cascini et al., 2016). The process of calculating emission includes preparing an inventory of equipment, determining installation emissions, operating emissions, disposal emissions and the total emissions (epa.gov, 2018d).

Conclusion

Emission Factors can be understood as an identifying value that can be used to compare the amount of pollutant created into the atmosphere and the function that causes the production of that pollutant. It is generally expressed as the pollutant's weight per unit weight/ volume/ distance/ duration of the process that is causing the pollution, for example, kg of particulate matter emitted per mg of fuel burned.

Impact of water conservation on GHG emission:

Conservation of water has long been considered as an effective social and institutional adaptation towards reducing the negative effects of global warming. Reducing use of water (and limiting its wastage) also helps to limit the consumption of energy that is used for the extraction, processing and distribution of water, and this concept is gaining popularity in several countries (Nair et al., 2014). Additionally, energy is also needed for the management of wastewater and processing it for reuse or recycling. By limiting the use of water, the need for recycling also decreases thereby further helping to reduce the emission of greenhouse gases. This is also a significant strategy considering the limited amount of fresh/drinkable water that is present on earth, which can be safeguarded through the more efficient use of water and lesser wastage (Sapkota et al., 2015).

The energy savings that can be achieved through water conservation includes direct savings in the energy that is used to heat water (which can be calculated from the specific heat capacity of water and the rise in the temperature of water due to heating), embedded energy savings to make chemicals to process or purify water and also by reducing the carbon footprint associated with the usage of water (Bartos & Chester, 2014). According to the California Energy Commission, water conservation programs in urban areas can help to achieve 95% savings from 2006-2008 energy savings programs at 58% of the expense (Escriva-Bou et al., 2015). Studies show that about 116 million pounds of carbon dioxide are produced each year due to the collection, distribution and treatment of drinking water, which is equivalent to the number of greenhouse gases produced by 10 million cars. The connection between energy expenditure and water use is strongest in the drier parts of the United States such as the Southwest where a significant amount of energy is needed for transport water (Hardin et al., 2017).

According to a report by the Los Angeles Times, the historic drought in San Diego County have helped to understand that reduction in the urban use of water has resulted in a lesser use of electricity and emission of greenhouse gases. This shows that by conserving water and preventing its wastage can help to reduce the emission of these gases. During the droughts in California, the state government restricted the use of water by about 25% from June 2015 to February 2016, which helped to save a total of 922,543 MW Hr of energy which is sufficient to power about 135,000 households for 1 year (latimes.com, 2018).

Sokolow et al. (2016) studied the effects of water conservation strategies in California on energy conservation efforts. Their study showed that using recycled water can help to conserve water, provide significant health benefits and also significantly reduce the consumption of energy and GHG emission caused by the urban use of water. Additionally, by reducing the emission of GHG and the usage of energy (for extraction, treatment and distribution of water) in urban areas can also help to mitigate the effects of global warming and climatic change caused by these factors. Similarly, studies by Zhou et al. (2013) showed that water conservation enabled about 70% savings in energy in Changzhou, China, and additionally, 13.9% of energy savings towards sustainable water management.

References

One of the main chapters of a research process is the research methodology which helps a researcher to identify the main research methods that are needed in the study in order to develop a credible and systematic approach towards the study. The chapter of research methodology helps to develop the quality of the research process by identifying the best research method that is suitable for the needs of the study and ensure that they are aligned to address the objectives of the research as well as the key issues identified in the research (Brinkman, 2017). In such a context, therefore, it is vital that the available research methods be analysed by the researcher in order to identify the tools which are most appropriate for the research, presently conducted. In the given research, the main focus is to identify the GHG that is produced by Tampa Bay, and how they impact the environment over a period of time, and to develop a methodology to calculate the emission of GHG due to the use of energy in water production. The study also aims to identify the link between water conservation and reduced utilization of water with a reduction in the emission of greenhouse gases due to a reduced utilization of energy by the water production plant, such as the Tampa Bay Water. Using the data, it would be possible to quantify the amount of emission that can be reduced with the conservation of each unit volume of water.

Method:

Emissions are quantified by the Tampa Bay Water, produced while pumping water to be distributed to the member governments. Using this methodology, it would be possible to identify the relationship between a reduction in the demand of water (and hence an increased conservation of water) with the reduced use of energy by the Tampa Bay Water, and also to understand how such approach will support a reduction in the emission of Greenhouse Gases.

For the methodology, the data is collected from the electrical usage by the pumping facilities at Tampa Bay Water between 2016, October and 2017, September. The Energy Consumption Manager application used by the agency is used for the data collection. Data for electric consumption was only partially available, due to which the total consumption of electricity was based on the production of water. The application can provide data with great accuracy and also is up to date because of the automated collection of the data by the application from the network. This helps to provide great reliability to the data and hence an effective resource of information.

The data that is above listed is used in combination with the EPA emission data that is obtained from the website of Clean Energy eGrid and EPA's Air Market's Program Data. The most up to data for the regional power plants was for 2014 on the Clean Energy eGrid website. Data available at the AMPD website is fairly updated; however, the data only highlights the emission data for methane, carbon dioxide, sulphur dioxide, and nitrous oxide. Data from the EPA website provides data of only methane and carbon dioxide from various sources of fuel, many of which can be used for generation of power from water (heating water). The two resources (IPCC and EPA) are used to compare the data of the preceding year's emissions with the current year's usage.

The data on emissions obtained from EPA website is converted into pounds (lb) and then added to each energy source while to some of the power in megawatt hour (mWh) is transformed to kilowatt-hour (kWh) to calculate emissions in the pound, per unit of energy in kilowatt hour used. The calculated emissions (lb per kWh) that are obtained from each energy source is then multiplied to energy usage in kilowatt hour by Tampa Bay Water to calculate the net annual emission of greenhouse gases from the Tampa Bay Water for water delivery systems. The emissions (in lb per kWh) is then multiplied by kWh per MG created to determine the emission per MG created in lb. For each of the emission type and source of energy, these steps are replicated.

In order to determine the emission of the greenhouse gases, using the data from water conservation, such as the quantity of water that was saved was collected by the member governing bodies, through the 5-year conservation programs. The amount of water saved (in Million Gallons or MG) is then multiplied by the amount of methane, nitrous oxide and carbon dioxide produced (in lb per MG), after which each of these valued are multiplied with 365 (for each day of the year) to calculate the net emission for each million gallons of water saved per year. The total reductions in the emissions per million gallons of water saved in MG/year or ton/year are then converted to metric tons from short tons. Dividing these valued by 4.7 metric tons the number of emissions can be calculated for each year.

Data interpretation of Primary Qualitative data collection

This study tried to address the four primary research questions that were posed by TBW based on the approach they used to calculate GHG emissions.

Are the methods for creating kWh used per production point being transformed correctly?

The kWh here is determined by the calculation of the production of electricity. The whole process of production involves estimating  kWh/MG and then the result is either multiplied by gallons or the gallons pumped. The result is averaged and the production of kWh per year is recorded. This may be inaccurate and hence the methods are not properly transformed to achieve the desired efficiency. There exists Green House Gas emissions, an evidence that the transformation of electricity is not according to the designated standards. These emissions emerge from the production of electricity to its consumption. More emissions eventually affect the production cycle of electricity hence the transformation becomes faulty.

Using the data from Tampa Bay Water, it is evident that they harvest the power usage conditions from e-grid. Most importantly, the table gives out a million gallons of water generated and directed from Tampa Bay Water (Barbeta et al.2015). It is quite clear that the individuals applied the correct methods.

The two and three scopes are the main sources of Tampa Bay Water GHG, this results in the existence of a small-scale clear point of production (Wani et al.2017). It is important to account for the indirect emission in scope according to GHG rules. Firstly, there is a missing transmission loss from the point of the power station to the facility point. Most of the essential energy is consumed. On the other hand, Tampa Bay Water applied chemicals to generate fresh water. However, the applied chemicals also form the portion of the indirect emission which to some existence is missed. Thirdly, the water facilities are formed by the sludge management system. In contrary, Tampa Bay Water did not account it. They applied the appropriate methods to come up with khw that is directed at every production point. It is quite clear that Tampa Bay Water, shown an appealing maturity for responding to their GHG emission calculation. However, the method is not fully final.

Are the methods for determining Greenhouse gas emissions per electricity used at sites being calculated appropriately?

The calculation in determining the Green House Gas emissions for the electricity used in sites passes through a number of stages and determinations. In the first stage, collection of data relevant to calculation of the emission is done. The data collected include the energy consumption collected from the Energy Consumption Manager, power billed commercially provided by the recognized public power providers’ agencies and the operating statistics retrieved from all supervisory control agencies’ facilities. A research on fossil fuel mix is also done for each utility basing the research on various EPA data (USEPA, 2017) The overall calculation done uses the above collected data including the amount of water produced and pumped. The methods involved in the calculations are correct and accurate since they show feasible reduction in emissions through the reduction of water demand and electrical usage (Shailesh, 2013). However, in some instances, there are minor assumptions and approximations that may mislead the overall results. The approximations never alter much the final determination from the calculations. The determination of the calculations was made correctly since it gives out accurate information on the GHG emission. Green House Gases determination can also be made through the analysis of the collected data and information plotted in graphs which will help to predict future occurrences of the emissions.

The member governments five-year plan provides Tampa Bay Water with information regarding the amount of water saved and GHG emission reduction which comes from the reserved water. After that, CO₂, N₂O, and CH₄(Ibis/mg) are multiplied by the MG saved after which every result is multiplied by 365 days in order to know the all the number of emissions reduction for saved MG in tons per year.

The electrical usage from Tampa Bay Water provides data for the methodology applied in this area. The data ranges from the facilities used in pumping water for the period of the year 2017. The data that is produced as emissions is directly changed to pounds (Ibs) and all of them are added to every source of energy. On the other hand, the sum of the megawatt-hour (MWh) that is generated is converted to kWh then applied with the sum of emission in order to find emissions Ibs per kWh. The kWh for water in Tampa Bay is multiplied by the total emissions in pounds per kWh (Dargahi et al.2016). This is done to every energy that is produced. The result of the multiplication shows the annual sum of greenhouse gas from Tampa Bay Water. On the significant part, in order to know the emissions per MG that are generated in pounds, the pounds for every kWh emissions are multiplied by kWh for every MG. all the above steps need to be done for every process.

It is imperative to determine the number of emissions that come with every electricity usage when calculating scope 2 emissions. Policymakers and the projects are the two core methods companies apply in order to transport emissions from greenhouse gas to the final use. There exist emission factors that the consumer greenhouse gas applies for every unit of consumption relating to scope 2. The factors must always be completed before transportation to the end user. The first factor from the guide is the location - based method and the approach that makes use of the market position.

It is clear that the approach of the market shows the electricity emissions that the organizations are at a position and able to come up with, however, location -based approach shows the average intensity of the emissions from the power table which takes in energy. Consequently, the location - based approach can be used in any place (Maupin et al.2014). It clearly shows the relationship between the collective consumer demand for electricity and the emissions from the locally based power production point.  

What averaging as well as standardized are used in cases where the data of electric consumption is not available from the local sources?

There are many standardized sources that could be used in place of the electric consumption data. In this case, the TECO data did not get processed in time for the use in coming up with the results for Water Year (WY) 2017. In case of such an incident, we could instead use the data obtained from the general supply which is the used electricity as measured from the grid without consideration of controlled load (Management Association, Information Resources, 2015). Off peak controlled residential hot water data can also be used, mainly obtained from hot water storage systems. Data could also be obtained from small-medium, non-residential sites for instance those non-residential consumers with low voltage use over a larger period of time usually approximated to be using below 160 MWh annually. Considerations could also be made for the non-residential consumers with an average of 160 MWh or higher. In addition, data from the non-residential high voltage consumers, like big industries large hospitals and universities and transport infrastructure, would be used in the overall calculations. Weather variations should also be included since the consumptions are strongly weather influenced (Santamouris, 2010).

Auto-generators surveys could also provide substantial information regarding the electric consumptions. The surveys could be undertaken by a group or an interested party performing statistics about the consumption and usage of electricity. Also, auto generators could play a great role in providing data since it provides the summary of the distribution of units and percentage losses involved during the whole process of transmission of electricity. Single electricity market operators provide information about the export and import of electricity in every half of an hour. Exelon provides monthly data regarding the transmission and loses of electricity in the main National Grid. 

What can alternative (standard) GHG emissions data be substituted for EPA emission factors if they are not up to date?

If the standardized emission data is not available, then product inventory need to be prepared for the products which are emitting it. Post that the sale number and the current usage numbers need to be quantified and an average need to be prepared for the emission pattern. One of the other possible ways would be to look at historical trends and then see the growth on the products which are doing the emission. This can give a fair idea of what is the emission.

Some of the standardized Green House Gas emissions data that could be used include the environmental changes to be observed for a longer period of time, approximately two years or more (NRC, 2010). Also, the production of electricity from its initial stages to the supply and usage of it should be observed and how it affects the environment in relation to the emissions of gases to the environment. The number of electric companies should also be taken into consideration while determining the emissions of the Green House Gases since they play a great role in the conservation of the environment through the controlled emission of the gases that could last longer in the atmosphere for approximately 2 to 10 years (Smick, 2006). Data from relevant agencies could also be utilized since they are majorly tasked with the observation and control of Green House Gas emissions. The data given would help in the analysis and determination of the gases and hence EPA would not be totally relied on.

Equivalently, calculations could be made based on the previous experiences to help predict the future occurrences of the Green House Gas emissions. This is achievable through construction of graphs to show trends.  However, these calculations may not give accurate information required but can give close estimates that could be relied on. Information can also be gotten from the power grid concerning the consumption of electricity and possible effects to be encountered by the Green House Gases as a result of the production and usage of electricity.

Florida’s gubernatorial administration in the year 2007 had issued three executive orders and this has been done to address the change in climate. In the year 2009 to 2012, data showed that there is a marked reduction in the (-109,388 metric tons) in the greenhouse gas emissions from the state agencies in comparison to the baseline years (2006-2007). The reduction in the greenhouse gas emission is noticed due to the several factors, water efficiency in the government agencies. The data from the Tampa Bay Water along with the encouragement of the state environmental organizations has led to the development of reduction methodology and the emission methodology by the Tampa Bay Water. These are discussed and described below and quantifies emissions associated with the water production. Calculation of the data is vital in order to demonstrate the secondary benefits arising from the reduced usage of water in the Bay area and an increase in the greenhouse gases is detrimental to the environment and the human health.

 Thus, due to the TBW ‘s and the commitment of the Member Government in maintaining the sustainable practices has led to the adoption of the energy policy in the year 2016 to increase the agency energy use efficiency. The policy includes a variety of commitments that the Tampa Bay Water is to provide the safe and clean water that is made through the sustainable and the efficient practices. The creation of the energy policy is the first step towards the development of an Energy Management system the emphasises in improving the energy consumption, energy efficiency, energy use and energy performance.  

According to the Congressional Research Service in the year 2010, it has been estimated that 12.6 percent of the nation’s energy is utilized in the heating, pumping and treating water (Copeland, 2014). Considering the supply side, pumping of water can be considered as the main energy consumer. This includes the delivery of water to the consumers, pumping of untreated water to the treatment plants. In each step kilowatts of electricity are used for supplying water. Thus, a reduction in the water usage leads to less utilization of energy and thus less water is required to be treated and pumped. A methodology was developed by Tampa Bay to calculate greenhouse gas emission which is associated with the energy utilization in the production of water. The methodology developed by Tampa Bay is based on data collected using the Energy Consumption Manager (ECM). The ECM can be described as the Enterprise Data Management System database for collecting data on consumption of energy and it is developed by TBW. An integrational system is placed on the commercial power billing data which is collected from 3 power providers and it includes the operation data and it includes the energy use, equipment time and flow rate. This information is collected from the agency’s data acquisition system and the agency’s supervisory control for all the agency’s facilities. The data on the fossil fuel mix for each of the utility data are determined and research is based on the different types of the EPA data and the contacts are made available via the electric utilities. The water demand and the management programs are consistent with the goal of the of the agency that emphasizes the energy costs and the energy consumption.

The EPA emission data are collected from the Tampa Bay Water for the year 2016 and this includes the electricity usage for the purpose of pumping water, amount of the water pumped and produced. The data compiled depict the possible reduction in the emissions and it has been made possible through the reduced electrical usage and the reduced water usage.

A hybrid framework can be applied for accounting the GHG emissions. The indirect emission can be calculated through a top down approach and the direct emissions can be calculated though a bottom up approach. The bottom up estimation and evaluation will be beneficial for calculating the emission factors. An agency can be set up that will establish, maintain and implement an Environmental Management System (EnMS) which will work according to the ISO 5001 international standard. If Tampa Bay Water also implements this EnMS then it can continue to reduce the overall energy costs and energy consumption while at the same time maintaining the water reliability and water quality. This, in turn, will reduce the amount of the greenhouse gas emission released due to the electric utilities. The efficiency can be increased by accomplishing the effectiveness of the operations; energy performance improvements in the modification of the agency's facilities, processes, systems, equipment; implementing energy improvement projects; energy efficient services and the products. Replacing the standard pre-rinse spray valves with the more efficient valves can reduce the water usage. As it is important to note that the heating water is energy intensive and if energy is required to be saved then there is a need to reduce the activities that demand energy-intensive operations. 

Conclusion

The study here focuses on a company called Tampa Bay Water and the greenhouse emission resulting due to its operations with the water utilities. After the State environmental agency adopted some serious policies, it was obligatory for TBW to work on its measurements and implementation of strategies of greenhouse gas reduction. It has been found that the usage of water by the residents for various purposes has resulted in to release of greenhouse gases into the atmosphere. It is, however, important to note that in order to mitigate an environmental issue it is always necessary to quantify the degree of the problem. Thus, to mitigate the several issues, TBW came up with calculations of the greenhouse gases from a single household and also from its operations. The TBW calculated the greenhouse gas emission in association with the production of water. The TBW calculated the data which included the nitrous oxide emissions, methane and carbon dioxide from a single family that uses hot water. The calculations emphasize on the reduction hot water usage which resulted in the reduction of greenhouse gas. The emission of the greenhouse gases that are produced by the usage of hot water at the homes, the percentage of indoor hot water usage and the data on energy intensity. The analysed data shows that a savings of 24.51 MGD resulted for the year 2017. Also, it is important to note that there is a reduction of 24,000 tons/year of carbon dioxide equivalent. Methane reduction has been noted to be 681 lbs/year and nitrous oxide has been noted to be experiencing a reduction of 506 lbs/year. The emission reductions have been found to be 1,656,523 lbs of carbon dioxide, 35 lbs of nitrous oxide and 240 lbs of methane. All the reductions remained avoided because of the conserved water through St. Petersburg, Hillsborough County and Pinellas County's pre-rinse rebate program.

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