Design for the Environment/Automobile Engines III

This page is part of the Design for the Environment course

Although internal combustion engine (ICE) have been fundamental to our modern society, conventional ICE vehicles that primarily use petroleum fuels account for 15 percent of the global carbon dioxide (CO2) emissions, a major greenhouse gas (GHG), and such emissions deteriorate the environment by eroding the ozone layer, depleting natural resources, and contributing to Global Warming. With the number of passenger cars expected to rise to one billion by 2020 from 806 million today, “radical changes in automotive design” and fuel efficiency are required to curb the trend of environmental degradation. The purpose of this report is to analyse the conventional gasoline ICE vehicle using a “wells-to-wheels” approach (considering both fuel and vehicle production) and compare it with two alternative concepts: the “wood-electricity-wheels” concept of electric vehicles (EVs); and “wood-ethanol-wheels” concept of flex fuel vehicles (FFVs) that run on ethanol-fuel mixtures. This reports’ client is Toyota Canada Inc (a subsidiary of Toyota Motor Corporation), a major car manufacturer that can use the results of the report to determine the best choice of energy source for its midsize automobiles. In order to be relevant to the client, all the alternatives were assumed to have the same performance as a 2009 Toyota Camry 2.4L, 4 cylinder, 5-speed automatic vehicle with an average gas mileage of 25mpg. All three alternatives were analysed systematically using life cycle assessment methods for an eight-year life with 15,000 miles travelled annually. Conventional ICE vehicles combust gasoline and generate rotational energy to power the vehicle. Such ICEs have been using gasoline as fuel for decades, often with additives that increase its octane number and reduce damage during operation. Recently, E85 ethanol (an ethanol-fuel mixture), which uses cellulosic ethanol derived from wood waste, has been used instead of gasoline in altered ICE vehicles. These “fuel-flex vehicles” have been successfully implemented with over 6 million on the road and can reduce the nations dependancy on foreign oil. Electric vehicles that use an electric motor that runs on rechargeable Lithium-Ion batteries are an alternative solution and although they eliminate tailpipe emissions entirely, there remains substantial emissions from electricity usage and the production of the batteries. These three alternatives were carefully analysed to determine which one is able to minimize environmental impact without compromising fuel efficiency and cost.

Highlights and Recommendation
The streamlined life cycle assessment (SLCA) and economic input-output life cycle assessment (EIO-LCA) models were used to determine the environmental impact of the three alternatives. Also, functional, cost and societal analyses were conducted to supplement our environmental analysis. These analyses were essential in determining key factors that might influence car manufacturers like our client when deciding on a vehicle type to manufacture.

Functional Analysis
Through a functional analysis, it was determined that gasoline ICE vehicles best consolidate gas mileage and fuel efficiency and deliver the most reliable performance. Although EVs have the highest gas mileage relative to other alternatives, electricity used in EVs has the lowest fuel production efficiency. Conversely, FFVs have the highest fuel production efficiency and the lowest gas mileage since E85 ethanol is an efficient energy source. FFV and gasoline ICE engines are highly compatibile, whereas there are major component differences between EVs and the baseline, such as the elimination of the engine, and the installation of Lithium Ion batteries and electric motors.

Environmental Analysis
The SLCA and EIO-LCA analyses were the focus of this report and from their results FFVs were found to have the least environmental impact over the entire lifecycle. The SLCA ranked EVs and FFVs as the top two alternatives (with a one-point score difference). Gasoline ICE vehicles performed poorly in the environmental analysis because of substantial emissions during the use stages from the production of gasoline and the direct tailpipe emissions. EVs have no direct emissions though they have substantial emissions from the production of electricity. FFVs which have a manufacturing process similar to that of gasoline ICE vehicles, have lower direct emissions. Though it was unclear from the SLCA which alternative had a lower environmental impact, after analyzing the alternatives with EIO-LCA and incorporating detailed emissions data and the resource extraction of the energy source (i.e. electricity or E85 ethanol), it was found that E85 FFVs rated the best because it had the lowest energy use (since it was re-using wood waste and not investing energy in its production) and the second lowest GHG emissions. This result confirms the SLCA`s finding that FFVs have the best environmental performance (i.e. the least environmental impact). Through EIO-LCA and SLCA methods, FFVs were determined to be the best vehicle type for the environment.

Cost Analysis
A summary of the cost analysis conducted over the eight year life of each vehicle is available below.

Although gasoline ICE vehicles are the most economical, FFVs have become increasingly affordable to consumers with government incentives. EVs have the highest cost of operation due to a large capital cost and are therefore unappealing to consumers. Other factors such as variety in the market and availability of fuel are other factors that may sway consumers minds. All these cost details are essential to Toyota Canada Inc. when deciding on a vehicle to make for consumers.

Societal Analysis
Through a societal analysis, EVs have been portrayed in the media to be the most environmentally friendly (despite contradictory evidence presented in this report), while FFVs have been supported by institutions like Canada‘s ATF that provide incentives to consumers encouraging use of alternative vehicles. Conversely, gasoline and gasoline ICE vehicles are deemed harmful to the society and thus they lack longevity in an economy with depleting natural resources.

Table 1B scores the findings from our report by first scoring the vehicle types in each section out of 5 (where 5 is an outstanding performance and 0 is a poor performance) and then assigning a weight that depends on the importance of each issue. The scores can be further explained in detail in the summaries for each section below. The SLCA and EIO-LCA were the focus of this study and were assigned a weight of 25% each. Consumers today are highly conscious of the fuel economy, which is why the cost analysis was assigned a weight of 20%. Lastly, the functional and societal issues were assigned a weight of 15%.

Recommendation
We recommend Toyota Canada Inc. should pursue a fuel-flex vehicle that operates on E85 fuel. FFVs scored the highest overall because of its relatively low environmental impact and low cost. FFVs scored the lowest in the functional analysis section because of poor gas mileage. However it should be noted that cellulosic ethanol production has the highest efficiency relative to the other energy sources. FFVs can be easily adapted to Toyota‘s existing fleet with minor alterations to a conventional vehicle. Aside from its poor gas mileage, FFVs scored high in the environmental and cost analyses. Consumers that value fuel economy will appreciate the life cycle cost of owning and operating an FFV ($39,275). Finally, FFVs are being promoted by institutions such as Canada‘s Alternative Transportation Fuels which encourage consumers to purchase vehicles that operate on biofuels. FFVs offer measurable environmental improvements over conventional vehicles (2.3 MTCO2E less GWP emissions) at a small expense to the consumer (FFVs cost $146 more than conventional vehicles over an eight year lifespan.) Finally, FFVs are a possible solution to Toyota‘s ‘Aim: Zero Emissions‘ strategy that strives to reduce emissions over the vehicles entire lifecycle.

However, it should be noted that gasoline vehicles had the lowest cost and greatest functional performance making them an ideal choice for economical consumers. Conversely, EVs offer few advantages and have been found to have the most negative environmental impact and highest cost. EV technology needs to be further developed to eliminate substantial emissions from battery production and electricity generation.

Details of Functional Analysis
For the functional analysis, the following two aspects of each vehicle concept are considered: the energy source and its efficiency; the type of engine used and its ability to meet the desired function (provide rotational energy equivalent to a 2009 Toyota Camry LE). Table 2 below summarizes the research used to form our conclusions.

Gasoline ICE Vehicles
Gasoline ranks as one of the most efficient energy sources because it is relatively economical to extract gasoline from crude oil and is widely available inexpensively to all consumers via various petrol pumps, making gasoline powered vehicles affordable and convenient to use. However, gasoline is a non-renewable fossil fuel. When burnt, gasoline releases a number of toxic pollutants such as carbon dioxide, carbon monoxide, nitrogen dioxides and unburned hydrocarbons. Typically, a gallon of gasoline releases 19.4 pounds of carbon dioxide. Fuel economy in gasoline vehicles can be further improved by 30% with the addition of turbocharger and supercharger assemblies. For baseline alternative, the 2009 Toyota Camry is fitted with a a 2.4-liter DOHC 16-valve VVT-i 4-cylinder spark ignition engine. It is able to supply the car with 158hp at the rate of 5700rpm. It averages 21 miles per gallon in the city and 31 miles per gallon on the highway (average mileage is 25mpg ) making it a highly efficient gasoline engine.

Electric Vehicles
Electricity, stored in the lithium ion batteries, is the energy source used to power EVs. Wood waste from forest reserves is used to generate electricity to power the vehicle. Abundant availability of wood waste in the region of Nanticoke, Atikokan and Great Lakes Saint Lawrence (GLSL) region makes it a viable option in Ontario. However, electricity production from wood waste is the least efficient energy source in this discussion as seen from table above. A lithium ion battery and an electric motor replace the engine to supply the car with 158 horsepower, which is equivalent to the baseline alternative (i.e. gasoline ICE vehicles). A single Lithium Ion battery charge is equivalent to 4 gallons of gasoline which will take the EV for 140 miles – that is a gas mileage of 35mpg. Thus, the electric vehicle is able to meet the functional requirement of providing rotational energy to the 2009 Toyota Camry, while running solely on electricity with no direct tailpipe emissions.

Flex-Fuel Vehicles
FFVs are the only vehicles that can use E85 fuel, which represents 85% mixture of ethanol with 15% mixture of petroleum (pure ethanol is rarely used as a fuel for transportation; conventional ICE engines can only operate on low ethanol content fuel). Ethanol production from wood waste is the most efficient production process relative to the other energy sources, as seen in the table above. Furthermore ethanol is water soluble, non toxic and biodegradable because it’s composed of fewer contaminants than gasoline. Some of the drawbacks of E85 include low availability of E85 stations, low fuel efficiency (during operation), and fewer choices in vehicles. The design of an ethanol vehicle requires few alterations from the convention gasoline vehicles. The alterations include adding a larger fuel tank because ethanol produces less energy than conventional fuel and changing the material of the tank and other components which would otherwise deteriorate due to the corrosive property of ethanol. In addition, the flex fuel vehicle has an engine control unit that controls the flow rate and adjusts the spark plug ignition to allow for accurate combustion. The resulting FFV has an average gas mileage of 17mpg.

Details of Streamlined Life Cycle Assessment
Using the SLCA model, a product life cycle of the engine and fuel type was evaluated throughout all life stages of the vehicle. Only the engine, and not the entire vehicle, was considered because it was assumed that all the other elements of the vehicle were assumed to be similar and thus irrelevant. The scoring criteria outlined in the SLCA text was used to create a 5 x 6 matrix (below), where each of the 30 entries was assigned a score between 0 and 4, where the lower value signified a greater impact on the environment (which is undesirable).

Gasoline ICE Vehicles
The product lifecycle (PLC) considered while analysing gasoline ICE vehicles is available in the figure below. Pre-Production and Production: At the automotive facility, steel and aluminum metal sheets are casted and/or forged, trimmed, polished and assembled together to form the engine and suspension that is fitted into the vehicle. This stage uses highly recyclable materials resulting in a high score in the matrix due to its low negative impact on the environment.

Distribution: After factory inspections, newly assembled automotive vehicle is sent to an auto dealership via car carriers or carrier ships. The per car impact on the environment during distribution is significantly low as a large number of vehicles are transported at a time. Delivery is common for all alternatives.

Use: The emissions are largest during the use phase. When burnt, gasoline releases large amounts of Greenhouse gases and other toxins into the air, resulting in a score of 0 in the Gaseous Residues column of the matrix. Drilling of crude oil from under the surface of the earth is highly energy intensive and thus given a score of 1 in the Energy Use column.

Gasoline life cycle (During Use Stage): Crude oil is pumped out from under the surface of the earth and refined using fractional distillation to obtain gasoline. This extracted gasoline is further supplemented with additives and transported to various petrol stations via pipelines.

End of Life: The car is sent to a scrap yard for recycling. At the yard, the car is reduced to different components and then crushed, shredded and sorted into metal sheets and rubber residue. The metal is reworked and reused while the rubber residue is sent to landfills. This stage has least negative environmental impact as these processes help reclaim 90-95% (by weight) of the car body. End of life of FFVs is similar to that of gasoline.

Electric Vehicles
A brief PLC for electric vehicles is available in the figure to the right and it is used to conduct a relevant SLCA. Pre-production and production: Raw materials needed to manufacture the lithium ion batteries, electric motor, generator and other electrical components will be extracted from steel, iron and aluminum ore. Extraction of lithium involves various metallurgical processes (Alkaline fusion,Acid roasting, Calcination, Carbonation and Mining). Use of material in rare quantities results in an overall low score in this category. (Electric Motor :Dysporium) All the raw materials obtained are pre processed (Mixing, Coating, Compressing, Drying and Slitting) to form the core before being sent to the cell assembly section. All these complex processes develop a need for automation which in turn results in high amount of energy consumption which in turn correlates to high amount of solid, liquid and gaseous residues in the atmosphere. During production of battery, corrosive chemical use (e.g.slurry in battery) results in high amount of energy being utilized. Therefore average to low rating is given in this phase.

Use with EV Life Cycle: Use stage is divided into two phases: the direct use and the resource extraction of the fuel(electricity). Owing to battery`s low reactivity to environment, it will produces minimal solid, liquid and gaseous residues which explains the high scores of 4 in this category. In resource provisioning phase,forest reserves are the primary source of wood waste. Wood waste is then transported to a nearby coal fired plant, processed and used in the burner to produce steam to run the turbines generating electricity. This operation results in a prime concern of ash disposal and air polluting emissions from combustion operations. Therefore,solid and gaseous residues are a prime concern in this matter and given a low rating.

End of life: Most of the steel components present in the car are either recycled in a scrap yard or reused by Toyota. Components such as wind-shields, batteries, motor and generator are recovered before the vehicle is sent for crushing. Disposal of the lithium-ion batteries is another critical aspect due to the presence of toxic raw material(Electrolyte-LiPF6). From batteries, raw materials such as copper, iron and cobalt are recovered and reused. All these operations result in high amount of energy needed to reclaim any reusable material in the whole process.

Flex-Fuel Vehicles
The PLC for FFVs is available in the figure to the below for use in the SLCA. Pre-Production and Production: During the pre-production and production stages, the engine is manufactured in a manner similar to the gasoline alternative with minor alterations, such as disregard of materials, such as, bare aluminum, magnesium and rubber because of the corrosive behaviour of alcohol. The pre-manufacturing score is insignificantly higher because it reduces the amount and type of material extracted for fabrication.

Use with FFV Life Cycle: The use phase is subdivided into both the resource extraction of the fuel and the direct tailpipe emissions from the fuel-flex vehicle. FFV's scored between the alternatives for direct emissions and the lowest during resource extraction. The provisioning of ethanol can be broken down into three steps: the collection of bark as wood waste from pulp mills; the transportation of wood waste to biorefineries for the gasification process and utilization of steam to produce a synthetic gas (syngas), which has low amounts of CO/H ; the filtration and cleansing of the resulting fluid. E85 is not transported using the conventional pipelines because it is prone to pick up extra water and impurities during the process and is therefore transported using trucks with corrosion-resistant tanks. The direct use measures the rotary power produced using E85 to fuel the vehicle. The end of life stage of ethanol minimizes environmental impacts in the atmosphere because of its biodegradable and high-evaporative properties. The direct emissions score is significanly lower because flex fuel engine produces less CO2, where ethanol contains more oxygen atoms that facilitates the combustion process using the ECU to burn cleaner fuel.

Details of Economic Input-Output Life Cycle Assessment
The Economic Input-Output Life Cycle Assessment provides a quantitative impact analysis by computing the potential environmental impacts over the lifecycle using the online EIO-LCA database model developed by Carnegie Mellon University. For the purpose of this analysis, the entire vehicle (and not just the engine, as in SLCA) was evaluated. Since the EIO-LCA model does not have a sector specifically for emissions during the use stage (e.g. tailpipe emissions), additional literature data was used to calculate those environmental impacts. The EIO-LCA model was used to determine the global warming potential (GWP in MTCO2E) and energy use (in Joules) of all life stages of the vehicle, as seen in the figures and table in this section:

Gasoline ICE Vehicles
According to EIOLCA, we observe that Gasoline ICE vehicles have a GWP of 71.8 MTCO2E consuming 0.781 TJ of energy over the average lifetime of a car. During pre-production and production stage, the power generation and supply sector is the maximum contibutor of global warming releasing 2.57 MTCO2E of Carbon Dioxide per car produced. It also accounts for 48% of total energy consumed by the top ten sectors in this stage. This is mainly because the power mills require energy (from burining fossil fuels) to power their generators that in turn generate electricity that is supplied to other sectors/industries. Maximum emissions occur during the use phase which encapsulates emissions during resource provisioning, vehicle's use and its repair and maintenance. 0.835 MTCO2E of methane is released during the resource provisioning stage (extraction of gasoline) while 59.2 metric tons of greenhouse gases (including Carbon Dioxide) are emitted during the full fuel cycle over the average eight year period. This fuel cycle encapsulates all the direct and indirect emissions of carbon dioxide, nitrous oxide and methane during production, refining, distribution and final use of gasoline. Excluding car washes, the maintenance and repair of the vehicle averages 1.33 MTCO2E Global Warming Potential and consumes 16GJ of energy over the eight year life-span of the car. During the delivery of a 2009 Toyota Camry from a factory to the auto-dealership, we note a Global Warming Potential of 1.15 MTCO2E and energy consumption of 9 GJ. This delivery impact is common for all the remaining alternatives and will therefore not be looked into again.

Electric Vehicles
In the EIOLCA tool, custom hybrid model has to be used to asses the impact as current modifications are not incorporated directly in the Vehicles and Other transportation equipment industry sector. From the Automobile and Light Truck Manufacturing sector, the weightage of engine manufacturing is made zero as it doesn’t exist in the EV. Other three sectors (Motor and Generator Manufacturing, Storage Battery Manufacturing and Relay & Industrial Control Manufacturing) are modified accordingly. It is observed that Power Generation and Supply sector contributes the most to the GWP,GHG emissions and Energy utilization. Potential automotive parts are extracted as raw materials and processed in a manufacturing facility and then transported to automotive assembly. These facilities normally run throughout the year 24/7 and are strongly dependent on power generation and metals/non metals extraction sector. EIOLCA also encapsulated the Use phase discussing the direct and indirect emissions. For direct emissions, batteries are constantly being charged up delivering constant power to the car. Minimal/No emissions are generated in the car as no combustion takes place. For resource provisioning phase(indirect emissions), total amount of wood waste needed to run the car during its lifetime is calculated from the mileage of the car as it is found that 1050 KWh of electricity is generated using a 1000 kg of wood waste .Pulp mill or Saw Mill sector is used to determine the environmental impact associated with the use of wood waste.Deforestation is a major cause of concern for the GWP while running these mills. Removal of trees results in reduction of CO2 neutral agents (trees). Also some pulp mills use wood waste to produce steam to run the mill which also results in GHG emissions.

Flex-Fuel Vehicles
FFV's scored between the alternatives in GWP analysis and the lowest in energy use for the life cycle of the vehicle. The pre/post-production stage utlized the producer cost determined in cost analysis to observe the Automobile and light truck manufacturing sectors. The power generation and supply industry had the highest energy use with CO2 as the highest impact. Power generation and supply is a prime sector because of the energy intensive fabrication of the metal and nont metal products use highly automated machines running 365 days a year. In addition, from the high amounts of CO2 released; only half is absorbed by natural processes in the atmosphere. The indirect emissions, net cost of extracting wood waste for ethanol production was determined in cost analysis and utlized in the Vehicle Wood, Paper, and Printing industry group and pulp mills sector. The sector with the highest energy use and GWP is the Pulp Mills sector. Deforestation is the primary polluting process, releasing CO2 from trees and soil. Pulp mills use large amounts of energy to provide electricity and power immense grinders that break down the harvested wood; for this reason we observe that power generation and supply uses the second most amount of energy. Furthermore extracting wood is a very energy intensive process and requires large machinery to which the power and generation supply sector provides electricity and energy to run. The other basic organic chemical manufacturing sector is where the actual ethanol fuel is extracted and as we see it only utilizes 1% of the total energy consumed because the gasification process involves altering fluids and gases whereas the other industries processed solids, which require more powerful machinery.

Details of Cost Analysis
A cost analysis was conducted by including all direct and indirect costs involved in various vehicle types. A summary of our analysis is provided in the table below.

Gasoline ICE Vehicles
Direct costs: This includes the capital cost of the car, the fuel and its disposal. The 2009 Toyota Camry retails for USD 20,195 .Over the period of 8 years (15,000 miles annually ), the maintenance and repair cost is determined to be USD 2,697 and USD 1,467 respectively. The cost of disposing the car is calculated using the market price of disposing a car body and engine and their respective weights. Thus, the disposal cost works out to be USD 71.08. As a result, the total direct cost is determined to be USD 36,393.

Indirect costs: Health care costs of operating a 2009 Toyota Camry are observed in this section. For Gasoline, the costs are calculated to be 1.4¢/mile in rural areas 3.0¢/mile in urban areas. Assuming 45% urban driving and 55% rural driving, the health care cost is calculated to be USD 342 per year. Therefore, the average health care cost of the lifespan of the vehicle is determined to be USD 2,736.

Electric Vehicles
Direct Costs: Capital cost of the car is calculated using the retail cost of the standard 2009 Toyota Camry ($20,195 ),subtracting the engine cost($ 2000 ) and adding the cost for additional components(Storage Battery: $ 8767, Motor & Generator Manufacturing: $1,197 and Relay & Industrial Control: $1,700 ). Operational Costs are obtained by determining the amount of electricity utilized during yearly use of the vehicle (15000 Miles).This is then translated over the next 7 years using the inflation ratio and trend in electricity price fluctuation. It is also found that normal Lithium Ion battery lasts about 4-5 years. Therefore, another battery will be required after 4 years, which would add a replacement cost.Other direct costs include disposal cost at the end of life cycle.Car body is disposed of at a cost of $50.62 with the addition of separate disposal cost for the lithium ion battery which comes out to be $39.60.

Indirect costs: In order to promote green energy, Canadian Government has provided various monetary incentives in which 09 Camry Hybrid is given a rebate of $1,500. Due to minimal data available about fully EV, one can assume a similar incentive will be given in this case. Other indirect costs include health costs. In the case of EV, no health care costs are observed since the vehicle does not have any direct toxic emissions when in use.

Flex-Fuel Vehicles
Direct Costs: FFV's 8 year life cycle cost was 0.3% higher than the gasoline fuelled vehicle. The capital cost utilized in the EIOLCA is determined using the gasoline producer cost of the vehicle incorporating a fuel-flex capability cost to account for the difference in fuels. The present value of the ethanol production cost was determined utilizing the EIOLCA wood-waste resource provisioning cost with an additional facility-processing and filtration cost. The inflated price of E85 for the next 10 years was researched and then utilized to determine the life cycle cost of ethanol. Other expenses, such as, maintenance, repair and disposal was analyzed in a manner similar to that of gasoline ICE alternative.

Indirect Costs: Victoria Transport Policy Institute proclaimed that with urban and rural areas rates of $0.01/mi and $0.0005/mi respectively the health costs to drive with E85 fuel would be $930. In a hope to promote the use of clean-burning fuel, the provincial government tax incentive was researched to be available to all FFV consumers until 2010, or 2 years of the life cycle analysis. Disregarding incentives, FFVs cost $2,676 more than the conventional ICE vehicle. However, if the incentives are available, then they should consider FFVs because its only $146 more expensive.

Details of Societal Analysis
Though gasoline is an indispensible fuel source and has deep roots in the transportation sector, alternative fuels are a prominent topic in the industry. There are insufficient supplies of petroleum and fossil fuels to develop gasoline, which means our society cannot support conventional gasoline ICE vehicles indefinitely; a solution to this energy crisis needs to be found. Alternative fuels such as E85 and similar biofuel mixtures, which combine environmental friendly fuels with gasoline, are able to consolidate gasoline’s energy with biofuels environmental friendliness. However, as discussed above, E85 is currently in low availability in North America, and especially Canada, and therefore cannot be a permanent substitute for gasoline. EVs that run on electricity have also been proposed as a viable alternative to enginebased vehicles that rely on fuels. Government initiatives such as the AFA attempt to promote energy efficient vehicles such as EVs and E85 FFVs to lower and middle class families to encourage environmentally friendly vehicles in the mainstream. Popularity of EVs in the media (and conversely, the poor image of gasoline-powered vehicles) confuse customer‘s decisions regardless of the vehicles overall environmental and societal impact. Therefore, the automotive sector needs to consider public perception of the fuel choice when develop an energy efficient vehicle.