Energy Mix in Arizona
Margaret Shepherd
Capstone Research Paper 1
Mr. Livoni, Ms. Mailhiot, and Ms. Hampton
October 5, 2018
Introduction
The Brundtland definition of sustainability says that in order for a society to be sustainable, it must meet “the needs of the present without compromising the ability of future generations to meet their own needs.” First, a society must fulfill their vitality, or the four basic needs for survival, which are food, water, oxygen, and shelter. Next, a society can work on increasing their integrity, or their well-being of life, which includes things like, security, healthcare, and freedom of choice and action. Sustainability encompasses three aspects of life: society, the economy, and the environment. All three aspects, or pillars, are interdependent. If one pillar fails, the other two cannot stand as well. However, both society and the economy are constrained by the environment. Neither can function without the support of the environment, and either directly or indirectly get all their resources from the environment. The parts of the environment that are relevant to human societies and economies is called natural capital. This includes natural resources, which are things that the Earth has, like water, air, timber, and wild animals, and ecosystem services, which are things that the Earth does, like cleaning water, regulating the climate, photosynthesis, and nutrient cycling. Whenever there is a change to a natural system, like a drought or flood, the people who are most impact are the poor, sick, disabled, young and old, and women. Transitioning to a sustainable society ensures a healthier environment and a more reliable future.
The energy mix of a particular region is the distribution of various sources of energy. An energy mix can be made up of nonrenewable and renewable energy sources. Nonrenewable sources cannot be naturally renewed by the Earth on a human timescale, so if humans keep using them, they eventually be used up. Fossil fuels and nuclear energy are examples of nonrenewable energy sources because coal, oil, and uranium are not naturally remade by the Earth on a scale that is useful for humans. Ideally, a society’s energy mix would be made up of renewable sources, which can be replenished by the Earth within hours to centuries, as long as humans don’t use it up too fast. Wind, solar, and hydroelectric power are examples of renewable energy sources. In fact, these are also all examples of inexhaustible resources because they come from a continuous supply.
DESCRIPTION OF PROBLEM AND STAKEHOLDERS
Arizona’s energy mix problem poses multiple challenges. In Arizona, including the Navajo Nation, the aim is to reduce reliance on fossil fuels and move toward alternative energy sources, preferably renewable alternative energy sources. Alternative energy sources are sources other than fossil fuels; these sources can be nonrenewable or renewable. Fossil fuels are limited and contribute to global warming, so it’s in the interest of Arizona’s economy and environment to reduce dependence on fossil fuels. Adverse effects of burning coal and petroleum include a higher risk of respiratory harm. The Phoenix-metro area experienced 110 days of elevated air pollution in 2016. Alternative energy sources can be tailored to meet a specific region’s or function’s need, contribute less to pollution, and be less wasteful. However, both alternative and renewable sources have their own problems. In 2016, Arizona’s energy mix of production was made up of nuclear power (338.6 trillion British thermal units), coal (116.7 trillion Btu), and renewable sources like hydroelectric, biomass, and solar (137.8 trillion Btu). Of the electricity it produces, the vast majority comes from nuclear power, coal, and natural gas; only 15% of Arizona’s net electricity generation comes from renewable sources. Arizona has high potential for generating solar energy, though only five percent of its net electricity generation is from solar power. However, the use of solar power for electricity is often discouraged by utilities companies because fossil fuels are cheaper, though increasingly cheaper and more efficient solar technology is coming to the market. Arizona’s main sources of hydroelectric power, the Glen Canyon and Hoover Dams, powered by the Colorado River, also poses problems. Lake Powell, formed by one of Arizona’s biggest dams, loses an average of 860,000 acre feet of water annually because of evaporation and bank seepage. Another problem is uranium contamination on the Navajo Nation from over 500 abandoned uranium mines on the reservation. 12.5% of unregulated water sources on the Navajo Nation had surpassed the Maximum Contamination Level (MCL) of uranium set by the US Environmental Protection Agency (EPA). A sustainable solution for Arizona’s energy mix must address multiple issues and their causes, such as the unsafe nature of uranium mining, extraction and use of fossil fuels, disruption of the the Colorado River, and economic uncertainty due to Ballet Proposition 127 Clean Energy for a Healthy Arizona.
Stakeholders involved include oil, coal, and natural gas companies; the Navajo and Hopi Nations; employees at Kayenta Mine, the Navajo Generating Station, and the Palo Verde Nuclear Generating Station; and the people of Arizona. Oil, coal, and natural gas companies are invested in continuing their business, so they are opposed to further expansion of renewable energy. The Navajo and Hopi Nations are benefited by the mining industry, but have been significantly harmed by past uranium mining. Employees of Kayenta Mine and the Navajo Generating Station are at risk of losing their jobs due to the projected closure of all three locations because of a transition towards cheaper natural gas, and employees of the Palo Verde Nuclear Generating Station are at risk of losing their jobs if a Clean Energy proposition on the November 6 ballot is passed. The people of Arizona, particularly those in metro areas, are negatively impacted by fossil fuel pollution.
THREE PILLARS OF SUSTAINABILITY
ECONOMY
Arizona’s current energy mix, as well as related legislation, have economic ramifications across the state, but the most affected are Native Americans. The Navajo Generating Station, located on the Navajo Nation, is schedule to close in December 2019 as its owners decided to move toward cheaper energy alternatives. The closure of the plant will almost surely lead to the closure of the Kayenta coal mine, which sends all of its coal to the generating station. The closure of both of these facilities will have a stark negative impact on the Navajo Nation budget. If the plant had stayed open until 2044, as it was planned to do, it would have had a cumulative Gross State Product (GSP) of $20.46 billion (in 2011 dollars) from 2011 to 2044.
Figure 1: Summary of the Statewide Economic Impact of NGS and Kayenta Mine, 2011-2044
This positive impact will be lost if the mine and plant closes in 2019. The Navajo Nation’s budget is currently about $173 million budget; this will shrink by about $40 million if the mine and plant close. In addition, the vast majority of the plant’s and mine’s employees come from the Navajo and Hopi nations. Ninety percent of the roughly 500 employees at the generating station are Navajo. This loss of income for families and the nation as a whole will exacerbate economic problems on the reservation. The median household income on the Navajo Nation is $27,389, much lower than the AZ median $50,448, and the Navajo Nation poverty rate is 38%, much higher than the AZ rate of 15%. In contrast, the overall effect on Arizona will be relatively small, because extractive industries accounted for only 1.3% of the Gross State Product (GSP) in 2016. Though transitioning away from coal will have long-term positive environmental effects, its negative economic effects for an already-disadvantaged group of people are significant.
An increase in renewable energy statewide may have more general negative effects. A proposition that is currently on the Arizona ballot for November 6th is Clean Energy For A Healthy Arizona, also known as Proposition 127. This would require the Arizona Corporation Commission and their regulated utilities to gradually, over time, increase the amount of electricity they generate for retail sales to be from from renewable sources to 12% in 2020 and to 50% in 2030. While multiple renewable sources are available for use in Arizona, the most obvious one is solar. Two main concerns with this proposition are that it will increase electricity prices and lose money for the state government. However, predicting electricity costs is uncertain because new technology for renewable energy could significantly reduce the price, and the location of generating stations is significant in determining the availability of the energy, and therefore its efficiency and price. Concerning government loss of money, The Seidman Research Institute did a study using Arizona Public Service (APS) data to model the impact of Proposition 127 is passed in Arizona. Between the years 2019 and 2024, “Seidman estimates that the proposition would increase Arizona’s GSP by an annual average of $460 million. Between 2024 and 2030, Seidman projects annual GSP losses of $990 million.” This shows an increase in GSP on a short-term scale and then a decrease on a long-term scale. They also estimate that “On a statewide basis, the state and local governments would lose an average of $68 million in revenue annually between 2021 and 2030.” However, Arizona’s Joint Legislative Budget Committee regards both of these estimates as speculative because of a large possibility of change to technology and costs. Another possible, but uncertain impact is the expected closure of Arizona’s nuclear generating plant, the Palo Verde Nuclear Generating Station. Palo Verde generates 27% of Arizona’s electricity. Because Proposition 127 will require 50% of Arizona’s electricity generation to be from renewable sources by 2030, nonrenewable sources of electricity in Arizona must be pushed aside. Palo Verde’s share of electricity production is large enough that the plant will have to close in order to make room for renewable sources in Arizona’s energy mix.
Figure 2: Arizona Energy Production Estimates, 2016
This means that about 2,500 full-time employees will lose their jobs, and an average of $54.7 million per year from state, county, and city sales tax will be lost. In total, Palo Verde’s annual economic impact is estimated to be more that two billion dollars, which is aggregated from taxes, salaries, material and service purchases, and other sources. If Proposition 127 is passed, and the plant closes, Arizona will lose this major employer and their economic input. Transitions to different sources of energy require reorganization of jobs, facilities, and electricity rates, so requiring a faster transition may more quickly bring short-term negative effects Arizona’s economy. However, reducing Arizona’s reliance on nonrenewable energy resources will pay off in the future when those resources are no longer around.
SOCIAL
When reviewing the social effects of Arizona’s energy mix, the most general effects come from fossil fuels. Human health in Arizona is negatively impacted by increased fossil fuel pollution. Specifically, 4.6 million people in the Phoenix metropolitan area experienced degraded air quality for at least 110 days in 2016. Degraded air quality can have many negative health impacts, including asthma attacks, breathing difficulties, aggravated lung diseases, inflamed lung tissue, and cardiovascular problems. These problems specifically concern people who live in metro areas with lots of cars. Fossil fuel pollution can come from natural gas, coal, and oil. In 2012, there were 1,453 lbs./MWh of CO2 emissions, 36.2% of which came from coal and 27.3% from natural gas. Certain populations of Arizona are also vulnerable to extreme heat. Arizona has almost 200,000 people above 65 years of age or below five years of age, living below the poverty line, that are especially vulnerable to extreme heat. Overall, Arizona health is negatively impacted by air pollution from consumption of fossil fuels.
Further negative effects of Arizona’s energy mix once again are most heavily felt by an already-disadvantaged group of people, those on the Navajo Nation. First, Navajo elders have spoken against mining on the Navajo Nation on cultural and religious grounds. There are 523 abandoned uranium mines on the Navajo Nation, as well as the Black Mesa field/Kayenta coal mine on the Navajo and Hopi Nations, and the Dineh-bi-Keyah oil field on the Navajo Nation.
Figure 3: Abandoned Uranium Mines on and Near Navajo Nation
However, uranium mining contrasts significantly with Navajo teachings. Navajo elders taught that “uranium, or łeetsó (literally, “the dirt that is yellow”), is… a powerful element that can disrupt hózhó [balance] when it is misused or disrespected… Navajo natural laws charge the Diné with seeking ways to return łeetsó to its natural balance with Mother Earth.” Past uranium mining and the now-abandoned mines also have many negative human health effects. Between 1944 to 1986, almost four million tons of uranium were mined on the Navajo Nation. Elevated levels of uranium have been found in wells, rivers, public water sources, Navajo people’s homes, and of course the mines themselves. In wells and public water sources with elevated levels of uranium, levels were found in 2015 to be 43 parts per billion, which is well is above the EPA limit of 30 parts per billion. The Navajo Birth Cohort Study found high levels of uranium in the urine of 27% of the participants. Many homes have dangerous levels of uranium because they were built with uranium-contaminated rocks that miners took home from the mines. In 2017, 85% of homes that had been assessed had been found with uranium in the dust.
Figure 4: Contaminated Structures Assessments and Cleanups on the Navajo Nation
Overall cancer rates on the Navajo Nation doubled between the early 1970s to the late 1990s. Though uranium exposure has not been definitively attributed to cancer, the link has been established. In a study conducted between 1969 and 1993 among men on the Navajo Nation, 67% of the incidents of lung cancer on the nation occurred in former Navajo uranium miners. These high levels of uranium create lots of problems; drinking water with uranium can lead to bone cancer and weakened kidneys. Livestock are also watered with uranium-contaminated water. The effects of uranium mining have significantly hindered the Navajos’ ability to lead long, healthy lives and reduced their livelihood. The Navajo Nation is disproportionately more affected by uranium mining and Arizona’s choice of energy sources than the rest of Arizona.
ENVIRONMENT
Arizona’s choice of energy sources have significant negative effects on the environment, though there is room for improvement. Arizona has a large potential for solar energy; Arizona received more average daily sunlight from 1979 to 2011 than any other state in the contiguous US.
Figure 5: Concentrating Solar Resources of the Southwest United States
However, the majority of Arizona’s renewably-sourced electricity came from hydroelectric sources. Solar energy may overtake hydroelectric soon, as the percentage of electricity from solar energy in Arizona has risen over time. Five percent of Arizona’s net electricity generation came from solar energy, both utility scale and small-scale distributed sources in 2016. Even with this progress, natural gas, coal, and nuclear power provide the large majority of total electricity generation in Arizona.
Figure 6: Arizona Net Electricity Generation by Source, June 2018
Continued use of fossil fuels increases pollution in the air and expedites the greenhouse effect. In 2016 in Arizona, 5,422,850 tons of coal were produced, 8,000 barrels of crude oil were produced, and 47,000 million cubic feet of natural gas were produced. 36.2% of Arizona’s 1,453 lbs./MWh of CO2 emissions in 2012 came from coal and 27.3% came from natural gas.
Figure 7: Energy Mix Chart: Comparison of CO2 Emissions
Burning these fossil fuels results in air pollution, such as smog and air toxins, and an increase of overall temperature over time by trapping heat inside the atmosphere. Methane is a significant contributor to this effect because it is much more effective than CO2 at trapping heat. Methane emissions can come from the extraction and transportation of oil, coal, and natural gas. Such a pattern of warming can be seen trends over time. Phoenix is the second-fastest warming city in the US, with an average increase of 1.12℉ per decade, and Arizona is the fourth-fastest warming state in the US based on data since 1970. Whereas Phoenix had 121 days in 2000 that had a heat index above 105℉, it is projected to have 147 days in 2050.
Figure 8: Danger Days in Phoenix, Arizona
Fossil fuels also disrupt the nutrient cycles of phosphorus, sulfur, and carbon by putting more of those nutrients in the atmosphere than would normally be there. This disrupts natural cycles that regulate air quality and climate and moderate extreme events. For Arizona, burning fossil fuels contributes to an urban heat island, lower air quality, higher temperatures, and more extreme weather events, such as drought, heat waves, and monsoons.
The mining of uranium on the Navajo Nation for nuclear power and, in the past, nuclear weapons, has multiple negative effects on the aquatic environments in the Navajo Nation. Nearly four million tons of uranium were mined on the Navajo Nation from 1944 to 1986 and now there are 523 abandoned uranium mines on the reservation. High levels of uranium have been found in rivers, wells, and public water sources, and 12.5% of unregulated water sources had surpassed the maximum contamination level of uranium. This presence of uranium removes clean water sources, disrupts water regulation, and endangers the health of other wildlife, animals, and humans nearby. The negative effects of uranium contamination in water on the Navajo Nation are widespread and are not limited to humans.
The largest source of Arizona’s renewable electricity is hydroelectric power, which comes from 11 hydroelectric dams, the largest of which are the Hoover Dam and the Glen Canyon Dam. The Hoover Dam creates Lake Mead and Glen Canyon creates Lake Powell. Specifically, Lake Powell loses an average of 860,000 acre-feet of water annually due to ue to evaporation and bank seepage. Lake Powell is now 48% full and Lake Mead is currently 38% full. Glen Canyon Dam is also damaging to the ecosystem of the Grand Canyon. Sediment that is full of nutrients is crucial to replenishing beaches, sandbars, and other natural aquatic habitats for fish and wildlife, and Glen Canyon Dam blocks 95% of this sediment that would otherwise go downstream and through the Grand Canyon. Hydroelectric power prevents sediment from reaching beaches and sandbars that need it, disrupting the nutrient cycles in that area. This affects the animals and plants in that area and restricts their ability to sustain themselves in the future. Another negative effect of hydroelectric power in Arizona is a large negative change in water quality in the Colorado River that has damaged the local ecosystem, put native plantlife and wildlife in danger, and reduced sediment levels. The use of hydroelectric power prevents water regulation, soil regulation, nutrient cycling, endangers the health of other wildlife nearby, and loses water.
Conclusion
The United Nation’s seventh goal within their Sustainable Development Goals (SDGs) is to “ensure access to affordable, reliable, sustainable and modern energy for all”. While Arizona’s share of sustainable energy has increased over time, it still does not match Arizona’s production or consumption of fossil fuels. There are also negative consequences of renewable energy, such as a decrease in the aquatic health of systems in the Colorado River and the Grand Canyon. Native Americans are also significantly affected by mining on the Navajo Nation, both in their health and cultural values. Transitioning to more sustainable energy is causing controversy in Arizona because of its uncertain, but projected negative, economic effects. Not one solution, but rather many solutions, are needed to make progress towards the SDG #7.
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