Emerging Energy Technologies
Paul Alois, October 2006
Human beings have been on the Earth for 130,000 years. For most of that time, people depended on the strength of their muscles to manipulate their environment. Several thousand years ago humans began harnessing the strength of animals, and this unprecedented innovation formed a cornerstone of agricultural societies. The power of animals made the complex political systems, religions, and technologies of that era possible. Two hundred years ago another monumental leap occurred; the discovery that the latent energy in fossil fuels could be controlled thrust people out of agricultural societies and into the modern era.
Today, the stage is set for a revolution of equally dramatic proportions. People are becoming frustrated with the political, economic, and environmental costs of the present situation. Currently, a relatively small number of people control the world’s access to energy, and they use this as leverage to maintain power both within individual countries and on an international level. There is a growing desire for a system where communities can create and maintain their own sources of power.
Additionally, the world’s supply of fossil fuels is running out. The entire global economy is predicated on the assumption that there will always be ample fuel to power growth. However, the easily available oil reserves are running low and recent oil spikes have created global economic problems. Natural gas is also becoming problematic; the rate of new discoveries is dwindling, and the price of natural gas doubled in the U.S. between 2000 and 2005.
Lastly, the present methods of energy production are having drastic effects on the environment. Climate change aside, every ecosystem on Earth has been indisputably damaged by fossil fuel generated pollution. The planet exceeded its capacity to absorb this type of punishment decades ago, and the effects are becoming increasingly obvious.
This paper will discuss emerging sources of energy that have the potential to radically shift the political, economic, and environmental structure of society. These technologies will be divided into two categories: electricity generation and transportation fuel.
In 2005, the world produced 17,450,000,000 megawatt hours (MWh)I of electricity.
- Coal generated 40% of that amount.
- Natural gas generated 20%
- Hydroelectric power generated 16%
- Nuclear power generated 15%
- Oil generated 7%
- Alternative sources generated 2%
Over 60% of electricity generation worldwide came from fossil fuels, and their capacity is expected to grow by 2-3% every year. Although hydroelectric and nuclear power contributed significantly, they have debatable long term practicality. Hydroelectric power has limited potential for growth. Most suitable locations have already been developed, and recent studies suggest that they may be more environmentally destructive than traditional fossil fuel plants. Nuclear power is a fairly well developed technology that will continue to grow, but is has several limitations. The high environmental impact of mining, transporting, refining, and disposing of uranium is a problem. Nuclear power also has economic and social obstacles: nuclear power plants are very expensive to build and people vehemently resist having to live near one.
The four most promising emerging technologies for electricity generation are wind, solar, geothermal, and tidal energy. They are all environmentally friendly, and encourage a community based approach to power generation. There are some important statistics to keep in mind when evaluating the efficacy of these technologies. The cost of generating electricity from coal and natural gas is less than 1 cent per kilowatt hour (KWh). In 2005, about 13 MWh of electricity was consumed for every American. Lastly, an average power plant can generate about 1,000 MWI of electricity. The building cost of a coal burning plant is about $1200 per kilowatt,I and the cost of a natural gas plant is $700 per kilowatt.
Wind is often called a form of solar energy. When the sun hits the Earth, it warms some places more than others. This difference in temperature creates a difference in air pressure. Air always tries to fill out a space with equal pressure on all sides, so the air in our atmosphere is always rushing from high pressure areas to low pressure areas. This creates the phenomenon called wind. Wind power is created by attaching fans to a turbine. When wind spins the fans, they turn the turbine, and electricity is generated.
People have been harnessing the power of wind for over 1300 years. During the Middle Ages, Europeans used a large number of windmills for a variety of functions. Coal displaced wind as the major source of energy at the beginning of the Industrial Revolution, but recently there has been resurgence in wind technology. In the last thirty years, wind power has been the world’s fastest growing and cheapest alternative energy source, at only 4 cents per kilowatt hour. The installation costs are also very reasonable, at about $1000 per kilowatt for an onshore facility.
In 2005 there were 59,000 MW of wind power capacity installed worldwide. Most of that was in Europe, while the U.S. and India also contributed significantly. Wind power capacity increased by 11.5 MW in 2005, up 24% from 2004. This increase was also 40.5% higher than the additions made in 2003; a clear indication that the wind energy sector is growing. In fact, the Global Wind Energy Council expects that by 2010 global wind capacity will be 134,500 MW.
One of the most important factors contributing to the popularity of wind energy is its environmental benefits. Germany, the largest wind energy consumer in the world, has instituted a series of measures to make wind power economically viable. This was triggered by their 2012 goal of decreasing greenhouse gas emissions by 21% versus 1990 levels. The largest increase worldwide in 2005 was in the U.S., where individual states are adopting renewable energy standards for environmental reasons. Wind power has usually been implemented exclusively in developed countries, but India and China are breaking that standard. Both made substantial increases in 2005, and India is especially committed to encouraging wind energy growth.
One of the biggest obstacles in the expansion of the wind industry is finding suitable locations for large wind farms. Wind farms produce very little energy relative to the amount of space they require, although the turbines are spaced far enough apart that the land could be used for agriculture. One of the largest and most productive wind turbines in the world has a rotor diameter of around 80 meters, and can produce about 2.5 MW of electricity. Consequently, a wind farm would need four hundred such turbines to equal the productive capacity of a single fossil fuel plant. Considering that turbines must be spaced far apart, the actually size of such a wind farm could easily be over 1000 acres.
In recent years, offshore wind farms have increased in reaction to the logistical difficulties of onshore development. The greatest advantage of an offshore wind farm is that the wind is stronger and steadier over water. The greatest disadvantage is the increased cost of installation and maintenance, which can be as high as $1,700 per KW.
A serious complication with wind energy is the lack of control over output. Since a community’s energy needs vary widely at different times throughout the day, it is necessary to generate an appropriate amount of electricity for each part of the day. Fossil fuel plants have their energy stored in the fuels, and they can burn as much or as little as is needed. However, the amount of electricity that a wind farm can generate is completely dependant on the strength of the wind at any given moment. Therefore, communities that use wind power need fossil fuel plants to supplement their energy needs. In the event that a turbine generates more electricity than is required, the excess energy can be sold back to the main grid.
1.2. Solar Energy
The solar energy industry is complex and decentralized. There are essentially two types of solar energy: photovoltaic energy (PV) and concentrated solar energy (CSP). PV energy uses the electromagnetic properties of light to generate electricity, while CSP harnesses heat from the sun.
1.2.1 Photovoltaic Energy
PV energy generates electricity using a thin, wafer-like chip called a PV cell. The surface of the cell, which faces the sun, is connected to the back of the cell through a wire. When sunlight hits the cell, electrons near the surface are knocked loose. The electron imbalance between the surface and the back of the cell creates an electric current, causing electrons to travel through the connecting wire. The electrons are collected along the wire and used as energy.
According to Solarbuzz, a consulting firm and clearinghouse for PV energy, in 2006 global PV electricity capacity was 1,460 MW.
- 57% was in Germany
- 20% was in Japan
- 10% was in the U.S.
Although that is a very small fraction of global capacity, it is nonetheless growing at a rapid pace: there was an increase of 34% from the previous year. Germany’s “100,000” roofs initiative has been very popular, and has dramatically increased their PV capacity. In January of 2006, California’s state government appropriated $3.2 billion dollars in tax credits for PV development. Their goal is to have 3000 MW of PV power in California by 2017.
The two biggest problems with current PV technology are cost and efficiency. The installation costs are around $5,500 per KW,  and the cost per KWh is 20-40 cents. Although technological improvements have lowered the manufacturing costs of PV cells, rising demand has actually increased costs for the consumer. The most expensive and problematic element in PV cells is silicon. Silicon is also a key ingredient in semiconductors, which are used in computers. The demand for silicon has kept the price pf PV cells high. An additional complication is that there is a shortage of PV grade silicon.
In order to be competitive with fossil fuels, the PV industry will have to bring installation costs down to $1000 per KW, and bring generation costs down to 10 cents per KWh. In the last several years, silicon free PV chips have been developed using nanotechnology that could dramatically lower installation and generation costs. A factory is being built to mass produce these cells, which may be able to generate electricity at a cost of only 8 cents per KWh. Another technology, using cadmium and tellurium instead of silicon, reportedly has installation costs of under $1000 per KW. The largest PV solar power plant in the world is being planned in Australia. It will have a capacity of 154 MW, and cost $2000 per KW.
1.2.2 Concentrated Solar Power
CSP uses the heat from the sun for electricity generation. It does this by focusing a vast amount of sunlight onto a container. When the contents of the container heats up, the pressure created is used to spin a turbine. Although this type of technology does not receive as much publicity as PV, it has an equal growth potential. There are three types of CSP technologies: trough systems, power towers, and dish systems.
Trough system CSP technology uses semicircular reflective troughs to concentrate sunlight onto a metal tube. The tube is filled with a liquid that expands and spins a turbine. California has the largest trough system plant in the world, with a capacity of 354 MW. According to the U.S. Department of Energy (DOE), trough system projects being planned worldwide total over 200 MW of capacity. The construction cost of this technology varies, and electricity generation is not cost competitive. Another disadvantage of trough systems is the space required to build a plant; the facility in California covers 1,000 acres. The vast amount of land needed for these plants will slow the spread of this technology. Lastly, trough systems cannot store energy, so they suffer from the same logistical problems as wind.
Power towers use hundred of mirrors to concentrate light onto a container at the top of a tower. They offer several advantages over trough systems as they require less space, and the energy can be stored and used at any time. This technology has been successfully tested, and a plant is being built with a 40 MW capacity in the southwest United States. This plant will cost $2500 per KW, and generate electricity at 15 cents per KWh.
Dish systems use an array of large dishes that reflect light onto a container of hydrogen, which drives a piston as it heats up. This technology has only been used in tests, but a plan is underway to build an enormous 4,500 acre solar dish array, capable of producing 500 MW. The cost of building this facility and the cost of the electricity it generates is undisclosed, but manufacturers claim it will be on par with fossil fuels. If this plant is successful it could become the standard in CSP technology.
1.3. Geothermal Energy
Geothermal energy uses heat from the Earth’s core to generate electricity. Geothermal plants are built in places where this heat gets close to the surface and can be used to create steam, which spins a turbine. Geothermal energy has been in use for much longer than the other alternatives, and is competitive with fossil fuel plants. It also has a minimal environmental impact, and plants can generate electricity at 95% capacity for 24 hours a day.
In 2004, global capacity for geothermal production was 8,900 MW, a third of which is in the U.S. Iceland, Mexico, Italy, the Philippines, and New Zealand also generate significant amounts of geothermal based electricity. Geothermal plants cost around $3,000 per KW to build, and generate electricity at 6 cents an hour. Although they have much higher building costs than traditional fossil fuel plants, they cost much less to run and so become competitive in the long run.
The biggest problem with geothermal energy plants is that there are not very many suitable locations for their construction, and they cannot generate nearly as much energy as a fossil fuel plant.
1.4. Tidal Energy
Tidal energy uses underwater turbines that are spun as the tide comes in and out. This technology is still in a largely experimental phase, but it has the potential to effect the global energy situation in the coming decades.
The largest and oldest tidal power plant was built in France in 1966, and has a capacity of 240 MW. The plant is built across the mouth of a bay, which is called a “barrage” tidal power plant. It allows the tide to rise naturally, then dams up the water. As the tide lowers, the water is allowed to rush through the facility, spinning 24 turbines. It has recovered initial costs and creates electricity at competitive rates, and has had a negligible environmental impact. There are several similarly designed plants in Russia, Canada, and China. These plants are reasonably efficient, but there are a limited number of suitable locations for their construction.
More recent technology is adopting a less intrusive method of harnessing tidal power that can be used almost anywhere. Turbines are attached to the ocean floor in an area with strong tidal currents. The turbines are unidirectional, and have almost no environmental impact. The test phase of two of these newer tidal technologies is complete, but whether or not they are practical solutions remains to be seen.
Oil single-handedly powers 96% of the world’s transportation. Despite its many disadvantages, the world is consistently increasing its demand for this precious resource. Finding new and different ways to fuel global transportation is an economic, political, and environmental imperative. The most likely candidates for replacing oil are bioethanol, biodiesel, electricity, and hydrogen.
Bioethanol fuel can be extracted from the sugars in any plant, although not all plants are equally efficient. The two most common sources of bioethanol are corn and sugarcane. Sugarcane yields more ethanol than corn, but corn can grow in colder climates. Other plants, like switch grass and sweet sorghum, are being tested and may prove to be even more productive.
Bioethanol fuel has many advantages. It does not contribute to global warming. Although it emits CO2 when burned, that CO2 was absorbed from the environment and does not add to existing levels. Bioethanol can take advantage of most parts of the current gasoline infrastructure. All cars can run on a blend of 10% ethanol and 90% gasoline, and with minor modifications any car can run on much higher blends.
Brazil has become the world leader in bioethanol. There are several factors that make ethanol an especially attractive option for Brazilians. The country is located in a tropical climate, necessary for sugarcane. The country has a very large landmass in which to grow the crops, and there is a large low-wage workforce to cultivate it. Brazil is producing 4 billion gallons a year, which accounts for 40% of its fuel. Brazilian ethanol, being derived from sugar, is efficient enough to be cost competitive with gasoline. The government mandates that all gas sold must be a blend with at least 25% ethanol. However, ethanol is so popular that many gas stations are pure ethanol, which sells for half the cost of the blend. Car manufacturers are getting on board, and by 2007 all the cars sold in Brazil may able to use pure ethanol fuel.
The U.S. is producing about 3.5 billion gallons of ethanol a year, equal to about 1.5% of US gasoline consumption. Almost all U.S. bioethanol is made from corn, which is not as efficient as sugarcane. In 2006, a gallon of E85 (85% ethanol blend) cost $2.43, compared with $2.84 for a gallon of gasoline. However, E85 provides significantly less miles per gallon. Consequently, E85 is 40% more expensive than petroleum to go the same distance.
Bioethanol has several serious limitations. Global consumption of oil for transportation purposes is around 919 billion gallons a year. Sugarcane yields 662 gallons of ethanol per acre. Assuming each acre of sugarcane is only harvested once a year, satisfying current demand would require 1.4 billion acres: 60% of the area of the U.S. Another problem with ethanol is that it cannot be transported along existing petroleum pipelines, so new pipelines would have to be built.
A final difficulty is that several studies have suggested that ethanol has a negative energy balance, meaning that the energy investment in ethanol production is higher than the energy return. The processing of turning corn into ethanol has an indisputably positive energy balance, but critics point to the bigger picture. When the energy cost of growing the corn and transporting the refined ethanol is factored in, ethanol appears to have an overall negative energy balance. Similar big picture studies have shown petroleum also has a negative energy balance, but studies like these can be designed to prove almost anything and need to be looked at very carefully.
When Rudolph Diesel unveiled his new engine at the Paris Exposition in 1900 it was so well received he won the grand prize. He had developed an extremely efficient new type of engine, and it ran solely on peanut oil. Despite the original intent, diesel engines around the world would be fueled by petroleum for the next century. Diesel fuel from petroleum (petrodiesel) was simply cheaper than diesel fuel from biological sources (biodiesel).
In the 1980s, interest in biodiesel returned as people became more aware of the hidden environmental and political costs of petrodiesel. Companies in South Africa, Europe, and the U.S. began producing biodiesel for mass consumption. Also, people began creating their own biodiesel at home. Biodiesel is very simple to make, it simply requires the combination of natural oils and fats with alcohol. A 20% biodiesel blend costs as much as pure petrodiesel, make it a cost effective choice. 100% biodiesel costs 25% more than petrodiesel and is 10% less efficient, so it lacks the economic viability of the blend. Biodiesel also offers many environmental benefits. In a study analyzing the substitution of soybean biodiesel for petrodiesel it was reported that CO2 emissions dropped 78.5%, particulate matter dropped 32%, and carbon monoxide dropped 35%. However, nitrous oxide increased 13%.
As of 2005, 90% of biodiesel production occurred in Europe, where biodiesel accounts for 1.5% of the total diesel market. The U.S., Brazil, India, and China made up the remaining 10% of global production. Biodiesel production world wide increased at an average rate of 40% per year between 2001 and 2005, and future production increases could be even higher.
The biggest problem with biodiesel is the low gallon per acre yield of biodiesel source plants. Soybeans only yield 48 gallons per acre, and more efficient plants like sunflower and rapeseed only yield just over 100 gallons per acre. As the global population continues to grow, water and land intensive crops may become too valuable to turn into fuel. If biodiesel is going to become a significant alternative fuel, new sources must be found. One promising new study suggests that a type of algae may be the best future source of biodiesel. It is very easy to grow, and compared to sunflowers it yields 100 to 300 times more biodiesel.
2.3 Electric Cars
When gasoline electric hybrid cars went on the market in 2000, fewer than 10,000 of the vehicles were sold. Those numbers increased exponentially every year thereafter, and in 2005 alone over 200,000 hybrids were purchased by consumers. This unprecedented interest is an example of a new gestalt within modern society. Just as SUV’s appeal to a certain mindset, hybrids speak to a worldview that values material simplicity in a way that biofuels do not.
Hybrid cars cost several thousand dollars more than traditional cars, but can get 30-50% more miles per gallon. Hybrid cars combine a normal gasoline engine with a rechargeable electric battery that powers the motor. Earlier versions of hybrids depended on gasoline to start, and used electricity as a supplement while driving. The newest hybrid technology can start the vehicle without using gas, and only requires gasoline while driving at higher speeds.
Plug-in cars have recently come to the fore because they have the potential to dramatically reduce and even eliminate gasoline consumption. Cars with this technology are run by a battery that can be charged from any electrical outlet. Currently, these cars are far from economically viable choices. They cost a lot more than regular cars, and must be recharged frequently. Plug-in hybrids have more promise. They use a plug-in battery to start the car, and gasoline is only used when electric power is insufficient. However, these alterations are being added on independently and car manufacturers do not recommend them because they could damage the hybrid technology. In the next several years, a few automobile manufacturers plan to release their own versions of plug-in hybrids.
By 2015 annual sales of hybrid cars in the U.S. are projected to be between 500,000 and 3 million, versus sales of around 15 million for conventional cars. Currently, most of the interest in hybrids comes from people who are concerned about the political and environmental cost of oil. However, if the price of gasoline continues to rise, interest in fuel efficient vehicles will increase for purely economic reasons.
Hydrogen gas has been proposed as a possible future source of energy for powering transportation. Pure hydrogen is not found in nature, and requires energy to create. Therefore, hydrogen should not be thought of as a fuel in itself, rather it should be thought of as a way to store kinetic energy as chemical energy. Pure hydrogen can be extracted from many sources like using heat. Currently, many power plants only turn 30% of the energy in fossil fuels into electricity; the rest is wasted as heat. If that heat could be used to create pure hydrogen from natural gas, then the kinetic energy in that heat would be stored as chemical energy in hydrogen. The heat for this process can come from any source; some people have tried using solar energy. Also, the hydrogen does not have to come from natural gas; other materials like coal, biomass, and even water can be used as well.
Hydrogen powered cars would use a technology called a fuel cell. Fuel cells are devices that convert chemical energy into electrical energy. A hydrogen fuel cell uses pure hydrogen mixed with the oxygen in the air to generate electricity. The electricity is then used immediately, as a fuel cell cannot store energy like a battery. Fuel cells are currently very expensive
Hydrogen is still a theoretical solution for the problems create by oil dependency, and so far all that has been accomplished is some research and a lot of publicity. In the U.S., the government has unveiled a plan called the FreedomCAR. This plan has a 2015 goal of creating cheaper and more efficient technology for hydrogen production, transportation, and consumption. Critics of the plan say it is simply a way for fossil fuel companies to find a more politically acceptable way to make money. A company in California has begun selling hydrogen powered cars. However, they cost over $100,000, they need to be refueled every 80 miles, and there are only 13 hydrogen fueling stations in the state, so these cars are little more than toys for adults. Hydrogen transportation is currently very inefficient, and little progress has been made towards solving these logistical concerns. An Israeli company has developed a novel technique for generating hydrogen from metals within the car. The technology remains untested, but could prove revolutionary.
An environmental concern that has been raised regarding fuel cells is water vapor. Some scientists consider water vapor to be the main contributor to global warming. Fuel cells combine hydrogen and oxygen, and their natural byproduct is water. The water is released as steam, and if millions of people are using hydrogen fuel cells on a daily basis the amount of water vapor released would be significant. Industry spokespeople, however, maintain that the vapor could be easily captured.
Despite their considerable publicity, the emerging energy sources discussed in this paper are a very small piece of the energy pie. To put it in perspective, thousands of fossil fuel plants are currently running. All the wind energy in the world is equal to 60 average sized fossil fuel plants. Geothermal energy is equal to 8 plants, PV solar is equal to 1.5 plants, CSP solar is equal to half a plant, and tidal energy is equal to a mound of coal dust. Alternative fuels are doing little better. In 2005 the world consumed around 735 billion gallons of petroleum for transportation purposes. World ethanol consumption was around 10 billion gallons, and world biodiesel consumption was around .9 billion gallons; together they represent less than 1.5% of transportation fuel consumption.
In the coming decades wind energy will remain the most common alternative source of electricity, and will most likely become a major contributor to the overall energy picture. Solar energy will increase its market share, but major technological breakthroughs are required if solar energy is to have a significant impact. Geothermal energy will grow slowly, while the future of tidal energy is hard to predict. The most effective way for people and governments to ameliorate the pollution caused by electricity is simply to use less. More energy efficient buildings and appliances would go a long way towards reducing global consumption of fossil fuels.
In the transportation sector biofuels present a useful alternative to petroleum, but the extent to which they can be mass produced is questionable. Hydrogen power is even less likely, as the logistical problems inherent in hydrogen storage and transportation remain unaddressed. Electric plug-in hybrids that are capable of burning biofuels represent the best hope for drastically reducing the world’s dependence on petroleum.
The biggest conceptual obstacle facing emerging sources of energy is they must be cost competitive. From an environmental and social standpoint, these technologies far outperform fossil fuels. However, the primary way in which they are judged by both multinational corporations and individual consumers is on the economic bottom line. Real change will occur when issues like ecological protection, social stability, and political cooperation are given as much importance as economic growth. This worldview is growing rapidly in developed countries, and is beginning to spread to the developing world. As the desire for responsibly generated power grows, it will be the most powerful factor determining the future of these emerging energy sources.
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I A MWh is a way of measuring electricity usage. If 1000 devices that each used a kilowatt of electricity were simultaneously turned on, 1 megawatt of energy would be used. If those devices were left on for an hour, they would use 1 megawatt hour (MWh) of electricity. (1 megawatt is equal to 1000 kilowatts)
 International Energy Agency, Key World Energy Statistics 2006, pg 24
 Energy Information Administration, International Energy Outlook 2006, pg 8
I This is a separate number from MWh, which is discussed above. This number is the maximum amount of electricity that a power plant can produce at any given point in time. This is important because electricity demands by a population vary widely within a day. Using 1000 MWh in an hour is the same cumulative amount as using 2000 MWh in half an hour, but a power plant with a maximum capacity of 1000 MW would be unable to generate the second figure.
I Installation costs are measured in $ per KW of capacity. A coal plant with a total capacity of 100,000 KW that costs $1500 per KW would have a total construction cost of $150 million dollars.
 International Energy Agency, Renewables in Global Energy Supply, pg 2
 Global Wind Energy Council, Global Wind Report 2005, pg 6
 Global Wind Energy Council, Global Wind Report 2005, pg 7
 Global Wind Energy Council, Global Wind Report 2005, pg 7
 Global Wind Energy Council, Global Wind Report 2005, pg 13
 Global Wind Energy Council, Global Wind Report 2005, pg 36
 15 million barrels a day, 15x42= 630 million gallons per day, 630x365= 229,950 million gallons a year
 US DOE, EERE, Clean Cities Alternative Fuel Price Report, June 2006 Table 1
 60 million barrels a day, 42 gallons in a barrel 60x42= 2520 million gallons a day 2520 millionx365= 919 billion gallons a year
 AGMRC, Pipeline Consideration for Ethanol, John Whims, August 2002
 Biodiesel Survey: Global Market Survey, Case Studies, and Forecasts” by Emerging Markets Online, Oct. 2006 pg 2
 US DOE, EERE, Clean Cities Alternative Fuel Price Report, June 2006 Table 2
 “Lifecycle of Biodiesel and Petroleum Diesel for Use in an Urban Bus” conducted by US DOE and DOA, May 1998
 “Biodiesel Survey: Global Market Survey, Case Studies, and Forecasts” by Emerging Markets Online, Oct. 2006 pg 2
 European Biodiesel Board, Press Release, April 25, 2006
 “Biodiesel Survey: Global Market Survey, Case Studies, and Forecasts” by Emerging Markets Online, Oct. 2006 pg 2
 80 million barrels per day x 365 days in a year x 42 gallons in a barrel x 60% used for transportation