Reliability of Energy Sources

The reliability of an energy source is an important economic factor. Since large sums of electricity cannot be stored at a time, energy supply must meet energy demand in real time. This means that when the most electricity is being used, the most electricity must be simultaneously created, and vice-versa.

This creates an interesting and constantly changing problem facing energy companies. They not only need to predict electrical output throughout the year, but also throughout the day. After predicting the energy needed, they will need to actually produce it. If their prediction is wrong or they are unable to create the energy needed, ratepayers could experience a shortage or the energy company could waste a lot of money via wasted electricity.

Since this is the case, extensive research has gone into electricity usage over time. Looking at a figure provided by the U.S. Energy Information Administration, we can see that electricity usage on October 22, 2010 in New England peaked at 8 in the morning, called the morning ramp, and 6 to 7 PM, which is the peak demand time. This data follows a regular pattern of electrical use. High use when people get up in the morning, and high use right when they get home from work. These are times when the most electrical supply is needed.

hourly_big

This kind of data is also collected on a month to month basis. As seen in the figure below provided by the U.S. Energy Information Administration, electrical use goes in cycles with low use in the springs and falls and high use in the winters and summers. This is generally due to the use of heaters and air conditioners during these months.

CoalNatGasElecGenMatches

 

With this, the reliability of energy sources must be considered. Nuclear, natural gas, and coal are all time independent. You can always burn coal or natural gas, and you can always run nuclear reactors no matter the time of day or time of year. For renewables like wind and solar, this is not the case. The wind doesn’t always blow and the sun doesn’t always shine.

For solar, there are many parts in the country, including Colorado, in which the sun doesn’t shine during peak energy usage.  At 7 and 8 AM in Colorado in the winter time, the sun has hardly risen. By 5 PM, the sun has completely set in the winter thus completely missing the peak hour of usage. Furthermore, what if we experience large cloud cover or storms during times of high energy demands? Surely, there will be a shortage.

For wind, the story is similar. Luckily, the wind isn’t as variable upon seasons as the sun is, thus giving wind more chances of possible electrical generation time, but definitely not guaranteed time. There is no way to guarantee a satisfactory amount of wind will be blowing to ensure it will meet energy demands, thus making it unreliable.

Due to how unreliable renewable energy is, many countries, like Germany, are paying to keep coal generators in reserve in case the wind isn’t blowing or the sun isn’t shining. In the case of Germany, the government is paying billions of dollars to keep inactive coal generators in reserve. However, not only is it expensive to keep up the maintenance of these inactive coal generators, it is also expensive to flip these generators on and off (Porter).

A similar story occurred in South Australia. South Australia became heavily dependent on wind energy, though due to its unreliability, prices were unstable and surged frequently. The surges placed prices as high as $14,000 per megawatt-hour, frequently surged above $1,000 per megawatt-hour, and averaged at about $360 per megawatt-hour. The electrical prices seen in Victoria, Queensland, and New South Whales are around $50-$60 per megawatt-hour. Due to the surging prices, the South Australian government is begging and incentivizing gas-powered stations to begin operation again as reserve.

Cost of Energy Delivery

The cost of delivery is how effectively each energy can be transported to people, particularly high population areas. Since line loss, energy dissipating from electricity lines, occurs, it is important to put electricity generators close to the market it is intended to serve. The closer it is to the market, the less electricity is lost. Furthermore, putting up electric lines and the infrastructure associated with electric lines comes at a cost which is preferably avoided. This means the cost of delivery is highly dependent on where an electricity generator may be put.

Nuclear power plants are very flexible in where they can be placed. According to Lydia DePillis, an energy writer for Slate, the three factors considered in building a nuclear power plant is “state laws, geography, and the disposition of the local community.” Since the dispositions of the local community and state laws are variable and can be changed over a short period of time, they will not be considered in economic analysis, but will be examined further in the political implications section. When it comes to the geography factor, nuclear reactors need to be placed near large bodies of water, whether it is the ocean, a large river, or a large lake. The water source is used as a coolant for the reaction.

Since coal and natural gas are also thermoelectric power, meaning they create steam to spin electric turbines, they have similar requirements as nuclear energy. They require large amounts of water as a coolant, meaning they need to be placed near water sources. In Colorado, this limits us to the natural lakes, reservoirs, and rivers that can be seen in the provided figure. While reservoirs can be created specifically for nuclear, coal, or gas plants, this is an expensive and preferable option. However, there are water features spread out across Colorado, making it possible to construct these plants essentially anywhere.

colorado-river-map

 

For renewables like solar and wind, farms must be placed where they will be most effective. The wind doesn’t blow at the same rate everywhere and the sun doesn’t shine equally across the United States. Solar farms must be placed where they will get the most sun and wind farms must be placed where they will get the most wind. Looking at the map provided by the National Renewable Energy Laboratory, we can see where the sun shines most intensely in the United States and least intensely.   This map shows that the south western area of the United States has the most ideal sun exposure for solar energy, and the north eastern area of the United States is one of the least ideal areas for sun exposure. A majority of Colorado rests in 5.5-6.0  kWh/m2/day. While a lot of Colorado rests in a higher area of sun exposure, some of the most populated areas in Colorado, specifically Denver, Boulder, and Fort Collins, do no fall into, or barely fall into, the higher sun exposure areas, thus creating a higher cost of delivery for solar energy in Colorado.

national_photovoltaic_2009-01

Slide1

For wind, The National Renewable Energy Laboratory provides a map giving the average annual wind speed at 80 meters above ground level. This map shows that the central United States has the highest average wind speeds, making it more favorable to wind farms as compared to coastal areas. Most of Colorado ranges on the lower end of wind speeds from less than 4 meters per seconds to 5.5 meters per second, though the eastern side of the state ha pieces that can range 8.5 to 9 meters per second. These eastern areas would be the most ideal for wind farms in Colorado, but they are also far away from Colorado’s population centers like Denver, Boulder, and Colorado Springs thus creating a higher cost of delivery for wind energy.

USwind300dpe4-11

Slide1

Looking at these geographic implications, we can assess the relative cost differences of the energy sources for delivery. Natural gas, coal, and nuclear all are very versatile, as their only requirement is that they need to be near a water source. Wind and solar energy are less versatile and require higher levels of wind and sun exposure. However, sun and wind exposure do not always line up with areas of population, thus increasing its relative cost of delivery.

Cost of Development for Energy

Cost of development, also called overnight capital cost, is the cost of building the infrastructure and development for different energies. For nuclear energy, nuclear reactors must be built. For natural gas and coal, burning generators must be built. For renewable energy, wind and solar farms need to be built. These costs are not universal, though, and can depend on location and management. Under bad management or inopportune locations, costs can be higher than normal. Under perfect conditions, costs can be lower than normal. Furthermore, what is exactly the “normal” cost of development is difficult to determine precisely since there are so many factors that can go into this cost. To determine costs of development, recent projects for wind and nuclear will be examined as well as data from the U.S. Energy Information Administration for all sources.

In 2016, the first nuclear reactor in 20 years was built in the United States. The reactor, Watts Bar Unit 2, is overseen by the Tennessee Valley Authority and took 44 years to be constructed. However, there was a long hiatus of no construction for 22 of the 44 years. The reactor cost as total of $4.7 billion, and will add 1,150 megawatts of electrical capacity to Southern Tennessee. For every dollar spent on capital in this project, about 0.0002446 kilowatt hours are added in capacity. According to the U.S. Energy Information administration, the overnight capital cost of a dual unit nuclear plant is $5,530 per kilowatt. The fixed operation and maintenance cost is $93.28 per kilowatt-year. Nuclear energy has the most expensive capital and development costs out of the examined energy sources.

In Colorado, Xcel Energy is constructing its first wind energy farm, the Rush Creek Wind Farm. The wind farm is located east of Denver, and is estimated to be finished October of 2018. The wind farm will cost a total of $1.1 billion and will add 600 megawatts of electrical capacity to Colorado. For every dollar spent on capital in this project, 0.000545 kilowatt hours are added in capacity. According to the U.S. Energy Information Administration, the overnight capital cost of an onshore wind farm is $2,213 per kilowatt. The fixed operation and maintenance cost is $39.55 per kilowatt-year.

Coal and natural gas have multiple types of generators that can be used. For coal we will examine a single unit advanced pulverized coal generator and a single unit advanced pulverized coal generator with carbon capture and storage. For natural gas, I will examine a conventional combined cycle generator and an advanced combined cycle generator with carbon capture and storage. How these generators specifically operate is unimportant to this analysis, and only their costs will be looked at.

For a single unit advanced pulverized coal generator, the overnight capital cost $3,246 per kilowatt. The fixed operation and maintenance cost for a single unit advanced PC is $37.80 per kilowatt-year. For the same kind of generator with carbon capture and storage, the overnight capital cost is $5,227 per kilowatt. The fixed operation and maintenance cost is $80.53 per kilowatt-year.

For a natural gas conventional combined cycle generator, the overnight capital cost is $917 per kilowatt. The fixed operation and maintenance cost is $13.17 per kilowatt-year. For an advanced carbon cycle generator with carbon capture and storage, the overnight capital cost is $2,095 per kilowatt. The fixed operation and maintenance cost is $31.79 per kilowatt-year. Natural gas has the lowest capital and development costs out of the examined energy sources.

Lastly, for a photovoltaic, solar array, generator, the overnight capital cost is $4,183 per kilowatt. The fixed operation and maintenance cost is $27.75 per kilowatt-year. With these numbers, it can be seen that nuclear energy has an extremely high overnight capital cost, and a high, though comparable, fixed operation and maintenance cost.

Nuclear: Cost of Source Mining

This post will compare the spot prices of the mineral resources that go into different energy sources, and compare them to the price of uranium, U3O8. The sources that will be looked at are coal, natural gas, oil, and rare earth metals, which are used in renewables like solar energy. Since prices change depending on market conditions, it should be implied that the price indicated is an approximation of what the source fuels cost.

The price of natural uranium, U3O8, is $25.50 per pound, according to Ux Consulting Company. The ten year price ranging from $19 per pound to $139 per pound. The price of coal is $52.05 per short ton. The ten year price ranging from $50 per short ton to about $125 per short ton. The price of natural gas is $3.30 per million BTU. The ten year price for natural gas has ranged from $2.00 per million BTU to $12.00 per million BTU. Indium and tellurium are both rare earth elements that are frequently used in solar panels. Indium costs about $720.00 per kilogram, and tellurium costs about $51.34 per kilogram.

However, these units are all different from each other, and need to be converted to a comparable unit, which will be in heat content measured in BTUs. According to the Energy Information Administration, a short ton of coal produced about 20.16 million BTUs. According to the World Nuclear Associate, one pound of natural uranium in a light water reactor can produce 214,961 million BTUs. Since solar power is a renewable source, it is difficult to figure out how much heat content 1 kilogram of tellurium or indium will provide via energy generated. Not only is the source renewable, but it is also incredibly variable, as it depends how much sun is shining, what kind of solar array is being used, and what kind of maintenance is performed on the arrays.

With the numbers provided, the heat content provided per dollar spent on a fuel source can be calculated. For every dollar spent on coal, about 387,320 BTUs are produced. For every dollar spent on natural gas, about 303,030 BTUs are produced. For every dollar spent on uranium, about 8,429,843,137 BTUs are produced. It is worth noting that this is not the full price of generating this heat content, but just the price spent on fuel only. However, when considering fuel prices, nuclear energy is without a doubt the cheapest source.

History of Nuclear Energy in Colorado

Colorado’s history with nuclear energy is limited. Only one nuclear reactor has been built in the state, and it has since closed down. The plant was located east of I-25 near Plateville, and was named the Fort Saint Vrain Plant. It was built, owned, and operated, in a limited capacity, by the Public Service Company of Colorado, which now goes by the name Xcel Energy.

The Public Service Company acquired a license to build their high-temperature, gas-cooled reactor in 1973, and invested $240 million to build it. The plant began operating in 1979, and remained in operation for 10 years. Until it was transformed in 1989, it only operated, on average, at about 14.6% it capacity. In 1989, the Public Service Company transformed it into a natural gas electric generator for an additional $340 million, and spent $25 million to build a spent fuel storage. This fuel storage is still on site and is under the discretion of the United States Department of Energy.

Though there have been no other nuclear energy reactors in Colorado, the state has a significant history with uranium mining, which is a primary source of fuel for nuclear energy. The state’s history with uranium mining dates back to the early 1900s, when radium and vanadium experienced a huge production boom, which are accessory minerals to uranium.

During the 1940s due to the emergence of nuclear weapons, uranium was specifically targeted in Colorado in mass, which continued through the 90s due to a potential nuclear energy increase in the United States. One of the most significant producers of uranium in Colorado is the Uravan Mining District in Montrose County which contributed over 850 tons of Uranium to the Manhattan Project. From 1947 to 1970, the Uravan district mined and produced around 24 million pounds of uranium ore. Along with the Uravan Mining District, Colorado has hosted the Schwartzwalder Mine in Boulder, which produced 17 million pounds of uranium ore; the Thornburg mine, which produced 1.25 million pounds of uranium ore; the Cyprus Hill mine at Hansen Creek, which produced 25 million pounds of low grade uranium ore; and many other smaller operations.

According to the Colorado Energy Office, there has been no uranium mining in the state of Colorado since 2009. However, there are still 18 active uranium mining sites permitted, 12 on temporary cessation, and 1 pending approval in the state as of 2014. Though these active mines are permitted, none are actually operating.

Nuclear Energy: What about Chernobyl?

Ever heard of Godwin’s Law? It is a joke created by Mike Godwin that says that as a conversation on the internet, whether it be a comment section on Facebook or forum, grows longer that the probability of someone comparing an idea or argument to Hitler or Nazis becomes inevitable. I think something similar could be said about Chernobyl when discussing nuclear power. Chernobyl seems to always come up when discussing nuclear power.

In case you do not know, Chernobyl was a nuclear power facility located in the Ukranian state of the Soviet Union in which a unit, namely Unit 4, exploded and caught fire in 1986. 31 workers of the plant were killed. It is estimated that the disaster is the cause of over 7,000 cases of cancer throughout Ukraine, and the environmental effects has been catastrophic.

However, the takeaway from the story of Chernobyl is not the horrors of nuclear power, but the horrors of Soviet-style socialism and leadership. According to Grigori Medvedev, an engineer at Chernobyl, construction and safety checks for the plants were rushed for the sake of hitting deadlines and receiving bonuses provided by the Kremlin, safety violations were constantly overlooked for the sake of good reports to superiors, most of the workers at the time of the explosion were poorly trained, and managers decided to take the plant to very low power causing the plant to become unstable.

Chernobyl was a formula for disaster, but I think to blame the disaster on the dangers of nuclear power is a red herring. While there are many dangers to producing nuclear power, most of them can be avoided with proper procedures and precautions. Soviet leadership is 100% to blame for the Chernobyl disaster.

There are many things we use every day that provide potential dangers, but with proper precautions and procedure disaster is avoided. The same can be said with nuclear energy.

If you are interested in learning more about the Chernobyl disaster and what happened on that April day in 1989, I would highly recommend Grigori Medvedev’s book: The Truth About Chernobyl.

Nuclear Energy: Uranium Mining in Colorado

Colorado has a long and controversial history with uranium mining. While uranium did not get into extremely high demand until the early 1950s due to the Cold War and the development of nuclear weapons, Colorado began similar mining with radium in the 1910s and vanadium in the 1930s, which were popular for more commercial uses like paints and clays. Both radium and vanadium are indicator minerals for uranium, hence why their mining and extraction are so interrelated.

The first uraninite, also known as pitchblende, found in the United States was found near Central City, Colorado. While most the uranium used for nuclear weapons, specifically the Manhattan Project, came from Congo and Canada, Colorado, through the Uravan mining district, produced about 850 tons of uranium ore for weapons testing. Prospecting and mining continued to expand after World War II as the largest uranium deposit to be found in Colorado was discovered in the late 1940s. Due to recession, the scaling down of the Cold War, and uranium being released from weapon stockpiles, uranium mining decreased dramatically in the 1980s due to a large decrease in price. During the boom of uranium mining in Colorado (1948-1978), it is estimated that Uravan belt had over 1,200 mines and mined 63 million pounds of uranium.

Currently, Colorado ranks third for the most known uranium reserves in the United States, just behind Wyoming and New Mexico. Since 2009, there has been no major uranium mining in the state of Colorado, and there are currently no active mines. However, there are 31 permitted projects in Colorado.

While uranium mining has the potential to be a very lucrative industry in the future, especially if nuclear energy becomes more popular, it does come with externalities to the environment and public health. When it comes to describing nuclear waste, it is generally described in two tiers: low-level waste and high level waste, which refer to their level of radioactivity. Uranium mining, which produce mill tailings, is the source of low-level waste, while high-level waste refers mostly to used reactor fuel after the uranium has been used to generate electricity. According to the Energy Information Administration, “by volume, most of the waste related to the nuclear power industry has a relatively low-level of radioactivity”, meaning most of the waste comes from the extraction of uranium.

Mill tailings from uranium mining, which has the presence of its indicator mineral radium, will break down into radon, which is a radioactive gas that can collect in the atmosphere if special precautions are not taken. Furthermore environmental contamination can occur from the tools used if special precautions also are not taken.

While it is important to keep in mind the externalities of uranium mining when discussing nuclear energy, we must remember that these kinds of trade-offs exist almost anywhere in energy production. Wind and solar energy, as well as hybrid and electric cars, fluorescent lightbulbs, and Ipods, have very similar externalities to nuclear power as they use rare earth elements like lanthanum, cerium, scandium, terbium, and several others. When comparing the externalities of uranium mining to the externalities of other rare earth element mining, the risks are almost identical.