Portland General Electric’s (PGE) Boardman plant is a nominal 600 megawatt (MW) coal fired unit that burns sub-bituminous Powder River Basin (PRB) coal from Wyoming. This paper will cover the experience and results of PGE’s Boardman plant operating on 100% torrefied wood (TW) pellets at 255 MW consuming almost 5000 tons of pellets. Results were positive and include suitable handing after inclement weathering for months. Pulverizers were able to handle the TW pellets with adjustments, resulting in near 100% combustion efficiency. Particulates were controlled with an electrostatic precipitator (ESP). Topics investigated include torrefied wood production, fuel handling and storage on the front end of the test. Fuel handling, pulverization, combustion, emissions, and ESP performance were monitored during the test and are reported here. Several one mill tests were conducted prior to the 100% test to evaluate and improve mill performance. This test showed that a pulverized coal (PC) boiler can operate on 100% TW fuel with minimal operational changes.

Access to energy is crucial in tackling many of the current global development challenges that impact on people’s economic, health and social well-being as well as the ability to meet the commitments of reducing carbon emissions through clean energy use. Despite increased attention from multiple governments and agencies, energy poverty remains a serious sustainable development issue in many developing countries. To date, most research have focused on general access to electricity and the generation of clean energy to replace fossil fuels, failing to address the lack of basic access to clean energy for cooking and heating. More people in the world lack access to clean cooking fuels than to electricity. This issue is one aspect of a broader research which investigates the impacts of optimized energy policy and energy business models on sustainable development in developing countries.

Biomass torrefaction is a thermal pretreatment which takes place at a temperature between 200–300 °C in a non-oxidative environment. The process requires thermal energy for drying and torrefying the raw biomass. The amount of the required heat may vary depending on the biomass moisture content, operating temperature and residence time. The volatiles released during the torrefaction are usually burnt in a combustor to meet the heat requirement of the process. If the energy content of the volatiles is less than the thermal energy required for the process, the operation of the torrefaction unit is below the autothermal mode so an auxiliary fuel such as natural gas is burnt together with the volatiles. This paper investigates autothermal operation of a torrefaction unit which consists of a dryer, a torrefaction reactor, a combustor, and two heat exchangers. An experimentally validated process model is employed to identify a relation between the moisture content, torrefaction temperature, and residence time at autothermal operation. The model is capable of predicting the composition of volatiles and torrefied biomass, mass and energy yields, process heat requirement, and CO 2 emissions. The results are graphically presented allowing one to determine whether a torrefaction unit operates below or above the autothermal mode at given torrefaction temperature, residence time and moisture content. Furthermore, the effect of the main operating parameters on the carbon dioxide emissions of the torrefaction unit is discussed.

Electric vehicles (EVs) are receiving more attention these days because they are environmentally friendly (no emissions) and are much quieter than internal combustion engine vehicles with rapidly decreasing prices. One of the serious limitations of EVs is the limited driving range. When conventional heating and air conditioning systems are used in winter and summer, the driving range is reduced further because they consume a lot of electric energy stored in the batteries. A thermoelectric cooling system integrated with thermal energy storage has been identified as an attractive alternative to traditional air conditioning in electric vehicles. The main goal of such a system is to minimize the amount of electricity that is drawn for air-conditioning from the electric battery of the vehicle, thus eliminating further reduction in driving range. Not only is the alternative more light weight than the conventional vapor compression based air-conditioning system, it also reduces the amount of electricity drawn from the battery. The proposed system is comprised of thermal energy storage (TES) employing phase change materials (PCMs), thermoelectric electric modules, and a fan. The TES, also referred to as a thermal battery here, can be charged before at home or at a charging station before driving like the electric battery, and is discharged when used in driving. This study involved the design and development of a TES for EVs employing computational fluid dynamics and heat transfer analyses. The model includes all the key components such as thermoelectric (Peltier) modules, heat sinks and the PCM. Various simulations for thermal battery charging and discharging have been conducted to demonstrate the feasibility of incorporating TES coupled with thermoelectric modules.

One of the biggest issues associated to Carbon Capture and Utilisation (CCU) applications involves the exploitation of the captured CO 2 as a valuable consumable. An interesting application is the conversion of CO 2 into renewable fuels via electrochemical reduction at high temperature. Still unexplored in the literature is the possibility of employing a Molten Carbonate Electrolysis Cell (MCEC) to directly converting CO 2 and H 2 O into H 2 , CO and eventually CH 4 , if a methanation process is envisaged. The introduction of this concept into a reversible system — similarly to the process proposed with reversible solid-oxide cells — allows the creation of a cycle which oxidises natural gas to produce CO 2 and then employs the same CO 2 and excess renewable energy to produce renewable natural gas. The result is a system able to perform electrochemical storage of excess renewable energy (from wind or solar) and if/when required sell renewable natural gas to the grid. In this work, a simulation of a reversible Molten Carbonate Cell (rMCC) is proposed. The reference MCFC technology considered is that from FuelCell Energy (USA) whose smaller stack is rated at 375 kW (DC). A simplified 0D stack model is developed and calibrated against experimental data. The Balance of Plant (BoP) is in common between the two operation modes MCFC and MCEC. In the former case, natural gas is electrochemically oxidised in the fuel compartment which receives carbonate ions (CO 3 2− ) from the air compartment, fed with air enriched with CO 2 produced during electrolysis mode. The CO 2 in the anode off gas stream is then purified and stored. In electrolysis mode, the stored CO 2 is mixed with process H 2 O and sent to the fuel compartment of the MCEC; here, electrolysis and internal methanation occur. An external chemical reactor finalises the production of methane for either natural gas grid injection or storage and reuse in fuel cell mode. A thermodynamic analysis of the system is performed the yearly round-trip efficiency is assessed considering an assumed availability operating time of 7000 h/y. Finally, the overall green-house gas emission is assessed.

To reduce the dependency on fossil-based energy resources, the utilization of renewable fuels in unmodified diesel engines is gaining more emphasis from researchers in the recent years. The aim of the current study is to take part in the efforts being made to this regard by experimentally investigating a compression ignition engine fueled with different fuels ((diesel, diesel-biodiesel (B20), and diesel-biodiesel-butanol (BU20)) for their performance and emissions comparison. The experimental study was conducted in a water cooled single-cylinder direct injection (DI) diesel engine. It was operated at a constant engine operation speed of 1800 rpm and under varied engine load conditions. It is found that BU20 shows promising results in terms of performance and emissions characteristics as compared to using B20 and D100. Butanol addition to diesel-biodiesel blends is considered as an appropriate solution of higher density and viscosity the blend and thus for the sustainable usability of biodiesel. Maximum thermal efficiency improvement of 3.18% was observed at an engine load of 75%. The NO x emission was improved with BU20 as compared to the conventional diesel fuel (D100) at most of the engine loads. As an improvement on the engine performance and emissions is reported from the current study, the BU20 fuel blends can be used in similar engines with no further engine retrofitting. This blend can be a good environmental friendly fuel that can serve in the reduction of fossil-based diesel fuels. A further study on diesel engine tribology is required.

In a move to reduce dependence on imported fossil fuels, develop and utilize indigenous renewable and sustainably-sourced clean energy sources, the Philippines enacted the Biofuels Act of 2006 (or Republic Act 9367) that mandated blending of biodiesel with commercially sold diesel fuels which presently is at 2% coconut methyl ester (CME) by volume. Deliberations are underway to shift to 5% by volume so that data on the effects on performance and emissions of percentage blends are necessary. This study presents fuel consumption and emissions measurements of an in-use passenger van with a common-rail direct injection (CRDI) powertrain fueled with 2, 5, 10, & 20 percent CME-diesel blends by volume (designated as B2, B5, B10, & B20 respectively) driven on the Japanese 10–15 Mode drive cycle. Results indicate B2-B20 had only a marginal effect on heating values, fuel blend density, and maximum power. Relative to neat diesel, the blends showed a 1–5% lower specific fuel consumption (SFC) with B5 lowest. Mileage was 1–5% higher with the blends with B5 highest. CO decreased with increasing blend. THC emissions of B1-B20 were roughly half that of diesel. NOx from the CME blends was marginally lower than diesel. The CO and THC trends agreed with published literature and usually ascribed to overall lean mixtures and increased amount of oxygenated fuel at higher CME blends. The NOx results need further investigation as it seemed to contradict other studies. Based on these results, B5 yielded the best combination of fuel economy and emissions improvement over neat diesel and B2 without performance loss.

Computational Fluid Dynamics (CFD) study of compression ignition (CI) engines provides invaluable insights into in-cylinder conditions and processes, which greatly expands on the very limited detail provided by engine output measurements, fuel consumption measurements, and engine-out measurements of exhaust emissions. CFD modeling and simulation has therefore become an attractive alternative for engine analysis in place of full experimental testbed study in recent years. In this research work, the performance of a single cylinder four stroke diesel engine was investigated. Commercial simulation software ANSYS Forte was used to study the combustion and emission characteristics of a diesel engine, in order to establish strategies for improvement of in-cylinder combustion and emission control. Normal heptane (n-heptane) was used as the surrogate fuel to represent diesel. Simulation results are compared against data from experimental testbed studies in terms of in-cylinder pressure profiles, heat release rate and exhaust emission of oxides of nitrogen (NO x ), soot and unburned hydrocarbon (UHC) levels. The pressure trace from the simulations is found to be within a reasonable error limit of 10%. The combustion process is simulated with special focus on exhaust emissions of soot, NO x and unburned hydrocarbon. Graphical plots for mass fraction of soot, NO x and UHC are presented and discussed to elucidate the formation of these emissions. Graphics contours of temperature, NO mass fraction and oxygen concentration within the combustion chamber are also presented and discussed. The effects of injection timing on engine in-cylinder pressure, heat release rate and exhaust emissions are also studied by varying the injection timing and maintaining constant injection duration. Results are compared for the three different injection timings investigated, namely start of injection (SOI) 18° bTDC, 15° bTDC and 12° bTDC. Emissions of soot and NO x are found to decrease with retarded injection timing. However, the peak in-cylinder pressure is greatly reduced and hence the output power is low. Injection timing is found to have no significant effect on emissions of UHC. The optimum injection timing that gives high output power and relatively low emission is 15° bTDC.

Deliberations in the Philippines are underway on the shift to 5% (B5) CME-diesel blend from the current B2 blend. In support to said deliberations, a fuel economy and gaseous emissions study of B1–B50 CME-diesel blends was conducted using an in-use Asian utility vehicle running on the Japanese 10–15 Mode drive cycle. Results show that adding CME up to 20% by volume (B20) has a small effect on the heating values, specific fuel consumption (SFC), mileage, and maximum power. Relative to neat diesel, the increase in SFC, and lower mileage and power beyond B20 were attributed to lower heating values at higher blends. CO was practically constant while THC and NOx generally decreased with increasing CME blends. The CO and THC trends were ascribed to overall lean mixtures and increased amount of oxygenated fuel at higher CME blends. The decreasing NOx trend needs further investigation as it seemed contrary to other studies. Based on these results, the shift to B5 would insignificantly affect fuel economy and likely lessen THC and NOx emissions. B20 yielded the most emissions reduction without performance loss.

From a practical perspective, economics drive the development of distributed energy resource (DER) systems. However, the adoption of a DER system provides an opportunity for the end user to completely control their environmental footprint. This work examines the process of designing a DER system while controlling carbon emissions. A mixed integer linear program (MILP) for sizing and dispatching a DER system is developed. The MILP includes a novel formulation of constraints that govern utility natural gas, generator operational state, and charging of thermal energy storage. The MILP is executed using real energy demand data for the University of California, Irvine to optimally design a DER system that minimizes cost while also reducing carbon emissions by a specified quantity. Two primary technology scenarios are explored (DER including storage with and without electrical export). A trajectory of DER technology adoption is determined for both technology scenarios. The different operational methods through which each system achieved lower carbon emissions at minimum cost is examined. Finally, the cost to reduce carbon emissions is calculated for both technology scenarios.

The Philippine Department of Environment and Natural Resources (DENR) has issued Department Order 2015-04 (DAO 2015-04) or the “The Implementation of Vehicle Emission Limits for EURO 4/IV, and In-Use Vehicle Emission Standards”. This policy, coupled with the Philippine Biofuels Act of 2016 (RA 9367) should greatly reduce the environmental impact of local automobile emissions. Commercial fuel is a mix of local coconut methyl ester (CME) and neat diesel blend. However, commercial diesel fuel is still at 2% v/v as of 2016 in contrast to the 5% v/v set by the policy, part due to the fact that only few local studies are done to show the effects of higher percentage of CME, with most recent studies showing results against increased CME usage. The study shows the effects of the usage of higher CME percentage in accordance to the set schedule of RA 9367. Five fuel blends with varying CME percentages v/v (2%, 5%, 10%, 15%, and 20%) are used in a heavy duty turbocharged common rail direct injection (CRDI) engine. The engine is run on an eddy current dynamometer with steady state measurements at 50 to 500Nm with 50Nm intervals. Each fuel is tested at three pedal positions, alpha, (25%, 50%, and 60%) controlled directly from the engine control unit (ECU). Results show that higher CME usage does not result in reduction of power and achieved torque. There is, however, a significant increase in brake specific fuel consumption at higher percentages of CME. No significant change in carbon monoxide (CO) and unburned hydrocarbons of diesel (HCD) is observed but there is a significant increase in Nitrous Oxides (NOx) concentration as CME percentage is increased. However, brake specific CO and HCD were found to be out of standard for near no load and near full load operations. A similar trend is observed for brake specific. Brake specific NOx is particularly more problematic since all measurements were observed to be out of standard with maximum values of 1350% of the set EURO 4/IV standard. However, it is also seen that the performance of each blend does not significantly differ from each other. Nevertheless, there is still some potential in the usage of CME due to the fact that power and torque requirements are still met at the expense of higher fuel consumption; but with the opportunity of being self-sufficient as coconut-producing country.

Anaerobic digestion (AD) has gained popularity as an effective way to treat organic materials, produce clean energy, and reduce greenhouse gas emissions. There is a significant number of large-scale AD facilities operating world-wide, largely treating livestock wastes, and used primarily for electricity production in industrialized countries. At the same time, there are millions of small, household-scale ADs deployed in developing countries, mostly to provide biogas resources for heating and cooking. Decentralized low-volume AD systems could provide a local, renewable energy source (for electricity, heating, or both), reduce or eliminate waste disposal costs, and limit discharges of high strength wastes. The purpose of this study was to evaluate the feasibility of deploying low-volume anaerobic digestion (LVAD) systems at institutions generating significant food waste, using Rochester Institute of Technology (RIT) as a case study. Mass flows and energy balance, net present value (NPV), and discounted payback period (DPP) were used to assess the feasibility of implementing an anaerobic digestion system utilizing the campus organic waste resources. Our study showed that a positive NPV can be achieved if subsidies and incentives were applied to offset the initial capital investment. However, the economics can be improved by driving down equipment cost and accepting food waste from other establishments to generate revenue from tipping fees.

When a coal-fired power plant is considered for closure, arguments are commonly made about the loss of jobs and unrealized investments. Facing this pressure, governments are reluctant to enact enforceable emission standards, and these plants continue to emit pollutants into the atmosphere. As the equipment ages, the plants may retire, but in their lifetime they will cause irreversible environmental damage. This report presents a method to mediate this damage, create jobs, maintain the efficiency of the turbine, and maintain or increase the capacity factor of the plant. Solar parabolic troughs using molten salt technology are scalable and can meet the steam conditions of a standard Rankine cycle coal-fired power plant. A marriage of these technologies allows the parabolic trough field to be installed without new power generation equipment. The turbine, generator, and transmission equipment are already in place, and when compared to a standalone concentrated solar power (CSP) plant, can be amortized over a greater number of operational hours without the use of very large amounts of thermal storage. That allows for a reduction in capital investment compared to a greenfield CSP plant, and reduces the levelized cost of energy (LCOE) from the solar contribution to well below current US Department of Energy SunShot targets. Coal-fired plant operators note that they typically cannot operate at partial power output without reducing the efficiency of their turbine accordingly. So, while a photovoltaic hybridization can take advantage of existing transmission infrastructure, it will require that the coal-fired system reduces its output and will consequently reduce the efficiency of the coal cycle. If we have to burn coal, we should do it in the most efficient way possible. Hybridizing with a molten salt parabolic trough installation makes use of the same turbine as the coal-fired system, which maintains the overall efficiency of the turbine at its design point and optimal load. With this model, the coal plant can operate at full power, reduce overall usage of coal while maintaining or even increasing employment opportunities, and reduce CO2 emissions.

Much interest is given to the research in biodiesel these days. It is renewable and has similar properties to conventional diesel. Biodiesel is also generally seen to produce less emissions, hence it is seen as an attractive and a greener alternative source of energy. Biodiesels are also referred to as Fatty Acid Methyl Esters (FAME). They are obtained from the transesterification of oils from organic products such as animal fat or vegetable oil. Common biodiesel feedstocks are soybean (USA), rapeseed (Europe), palm, and coconut (Asia). The Philippines, being one of the largest producers of coconut in the world, should have a substantial interest in this. Biodiesel in the Philippines is obtained from coconut oil and is commonly called Coconut Methyl Ester (CME). There is a number of research works available that study the effects of biodiesel when used to run diesel engines, although there is notably less studies on CME and particularly Philippine-CME available. This work aims to show the fuel injection timing and duration of a Common Rail Direct Injection (CRDI) engine run by CME-diesel with neat diesel as baseline. There are two sets of injection parameters that describe the injection behaviour of an engine. The static injection parameters refer to the electronic commands given out by the Electronic Control Unit (ECU) while the dynamic injection parameters refer to the actual physical injection happening in the fuel injector nozzle. Knowledge of these information may help explain possible differences in performance and/or emissions observed in biodiesel-fed engines. The static injection commands were obtained by tapping into the solenoid signal wire from the ECU. The dynamic injection parameters were estimated from line pressure signals in the fuel injection line. All the tests were done on the AVL Eddy Current Engine Dynamometer in the University of the Philippines Vehicle Research and Testing Laboratory. Baseline data were recorded from 100% neat diesel, then volumetric blends B10 (10% CME biodiesel and 90% neat diesel) and B20 (20% CME biodiesel and 80% neat diesel) were mixed for the tests. The CRDI engine was ran at full load, sweeping the operating range at 400 RPM increments from 800 to 4000. The results showed no significant difference in the static injection parameters of the CME-diesel blend-fed engines as compared to being ran with neat diesel. As for the dynamic injection parameters, there were some significant differences observed in the higher engine speeds starting at 2800 RPM. The observed changes were attributed to the differences in the physiochemical properties of CME biodiesel as compared to neat diesel.

Combined Cooling Heat and Power (CCHP) attained significant attention among energy professionals and academicians recently due to its superior thermal, economic and environmental benefit in comparison with conventional energy producing systems (internal combustion engine (ICE), micro-turbine, etc). Despite the abundance of literature on CCHP, only a few studies emphasized on the selection of appropriate prime mover for an economically sustainable CCHP system. Furthermore, the effect of part load efficiencies is commonly neglected during CCHP analysis. We had introduced these two new concepts of economic sustainability of specific prime mover and part load effects on efficiency to CCHP system in our previous paper. An algorithm based on hybrid load following method was utilized to determine the optimum prime mover for a particular location and weather type. No studies explored the effects of efficiency parameters and the selection strategies of prime mover in different building types for any particular location using this newly developed algorithm. Since building types dominates the electric, heating and cooling demand extensively, it is imperative to extend the prime mover selection analysis for building types for efficient CCHP operation. Economic, energy, and emission performance criteria have been utilized for the prime mover selection systems in different building types. Computer simulations were conducted for five different building categories (primary school, restaurant, small hotel, outpatient clinic and small office buildings) for each of three different types of prime movers (reciprocating internal combustion engine (ICE), micro-turbine and phosphoric acid fuel cell) in a cold climate zone (Minneapolis, MN). The simulation results of different prime movers were compared with the outcomes of a reference case (for each building in the same climate zone) that has a typical separate heating and power system. The cold climate zone (Minneapolis, MN) helped to explore the heating load effects on economic, energy, and emission performance of the buildings in comparison to other energy demands (i.e. electric and cooling demand). A hybrid load following method was executed, using improvements shown in our previous article. Performance parameters and other outcomes of this study showed that economic savings were observed for the ICE in all building types, and the micro-turbine in some building types. Internal rate of returns of ICE are 22.4%, 14.7%, 20.5%, 14.6% and 6.5% for primary school, restaurant, small hotel, outpatient clinic and small office respectively. ICE also shows highest energy savings among all three prime movers with an energy savings of 20%, 17.2%, 25.7%, 23.8% and 9.7% for primary school, restaurant, small hotel, outpatient clinic and small office respectively. For all types of prime mover based CCHP systems, lower CO 2 emission was observed for all building types. However, unlike ICE, which is preferable in terms of economic and energy savings, emission analysis shows that micro-turbine poses better emission characteristics compared to other types of prime movers. CO 2 emission for micro-turbine savings are 67.1%, 62.2%, 82%, 43.2% and 81.4% for primary school, restaurant, small hotel, outpatient clinic and small office respectively. The relationship between the power and thermal demand of the different buildings was determined to be a significant factor in CCHP system performance. A sensitivity analysis determining the effects of heat exchanger and heating coil efficiencies on the performance of CCHP systems shows that the economic performance was most sensitive to the heat exchanger efficiency, while energy consumption and emissions was most sensitive to the heating coil and boiler efficiency.

Increasing grid penetration of intermittent renewable power from wind and solar is creating challenges for the power industry. There are times when generation from these intermittent sources needs to be constrained due to power transmission capacity limits, and times when fossil fuel power plant are required to rapidly compensate for large power fluctuations, for example clouds pass over a solar field or the wind stops blowing. There have been many proposals, and some actual projects, to store surplus power from intermittent renewable power in some form or other for later use: Batteries, Compressed Air Energy Storage (CAES), Liquid Air Energy Storage (LAES), heat storage and Hydrogen being the main alternatives considered. These technologies will allow power generation during low periods of wind and solar power, using separate discrete power generation plant with specifically designed generator sets. But these systems are time-limited so at some point, if intermittent renewable power generation does not return to its previous high levels, fossil fuel power generation, usually from a large centralized power plant, will be required to ensure security of supplies. The overall complexity of such a solution to ensure secure power supplies leads to high capital costs, power transmission issues and potentially increased carbon emissions to atmosphere from the need to keep fossil fuel plant operating at low loads to ensure rapid response. One possible solution is to combine intermittent renewables and energy storage technologies with fast responding, flexible natural gas-fired gas turbines to create a reliable, secure, low carbon, decentralized power plant. This paper considers some hybrid power plant designs that could combine storage technologies and gas turbines in a single location to maximize clean energy production and reduce CO 2 emissions while still providing secure supplies, but with the flexibility that today’s grid operators require.

Air pollution is a leading public health concern that needs to be tackled. About 30% of the total greenhouse gas emissions, such as CO, HC and NOx are due to automobiles. By 2030, the US Department of Transportation aims to reduce light duty vehicle emissions by 18%. This can be achieved by public policy approaches such as implementing emission control norms and performance improvements such as exhaust system design. In this work, the implementation of a pure Zeolite catalyst to reduce the exhaust CO 2 emission of a SI engine is studied theoretically and experimentally. The complete exhaust system including the catalytic converter, muffler, and pipes is modeled in a 3D CAD modeling software, using the engine specifications. Current expensive precious metals in the catalytic converter are replaced with a binding agent along with Zeolite catalyst. The exhaust system is fabricated and the experimental tests are performed at the maximum engine RPM to obtain threshold emission reduction values. The results showed obtaining an emission reduction of CO 2 at a lower cost. Furthermore, it is found that employing Zeolite sieves can further reduce the pollutant emission at a similar cost.

In order to reduce CO 2 emissions in the residential sector, the installation of photovoltaics (PV) has been increasing extensively. However, such large-scale PV installations cause problems in the low-voltage distribution grid of the residential sector, such as PV related voltage surges. In this study, the utilization of suppressed PV output through energy storage devices was proposed. Using demand side energy storage devices reduces voltage surge, transmission loss, and CO 2 emissions from the residential buildings. The objective of this study was to add voltage constraints of the low-voltage distribution grid to an operational planning problem that we developed for the residential energy systems, and to quantitatively evaluate the potential of heat pump water heater (HP) to utilize the PV surplus electricity, while considering the electrical grid constraints based on the minimization of CO 2 emissions. We found that when a 4.5 kW HP with 370 L storage, which utilizes PV output, was added to the system, the reduction in CO 2 emissions was more than twice compared with that in the case of adding 4 kWh battery (BT) to a PV and gas fired water heater configuration. Further, the effect of utilizing the suppressed PV electricity by HP was almost equivalent to that by the BT. Therefore, the potential of HP in utilizing PV surplus electricity is higher than that of the BT in terms of CO 2 emissions reduction in the residential sector.

There has been a global search for alternative fuels that are environmentally friendly to replace and or compliment the conventional fossil fuels used in running engines. This is in line with the global action to reduce CO 2 emissions hence ameliorating the effect of climate change. Biodiesel fuels have been adjudged to be clean energy with minimal environmental pollution during combustion. Hence, biodiesel fuels for running compression ignition engines have been developed from various feedstocks such as vegetable oils, animal fat, and waste or used cooking oils. The properties of these biodiesels have been reported to be dependent on the feedstock type and therefore vary according to the source feedstock. In carrying out this present study on the effects of utilising biodiesel fuel on the compression ignition engine, a numerical study of temperature distribution in the cylinder liner of biodiesel-powered compression ignition engine is presented. Biodiesel produced from palm kernel oil is used. Eight nodes in the cylinder liner spanning the top section of the liner, midpoint and the interface between the liner and the block were used as data source as it is established that sharp-edged points are most likely regions for thermal stress. Of the eight nodes selected, four were edge nodes and the other four were nodes at the interface with varying conditions. Model equations used for the study were developed and subsequently transformed using the finite difference method. Numerical solutions were obtained from computer codes written in MATLAB programming language. The obtained results from this code were compared to results obtained from commercial software (ANSYS FLUENT) for same geometry and boundary conditions. Results on the cylinder liner showed steady state temperatures were reached in about five minutes using both the MATLAB code and ANSYS FLUENT and both results showed a similar trend of temperature distribution in the radial direction. However, the MATLAB code showed higher temperatures at the upper section of the liner material as compared to the midpoint of the liner whereas ANSYS FLUENT showed the midpoint section to possess maximum temperatures as compared to the cylinder head section. Both results agree with the lower section having least temperature distribution. Further analyses were carried out on the midpoint of the cylinder and the cylinder head section and factors responsible for the discrepancies discussed. The outcome of this study presents palm kernel based biodiesel as an alternative fuel in cylinder engines while highlighting sections of the engine that require design attention in terms of heat flux and engine stability.

Sustainability of natural gas transmission infrastructure is highly related to the system’s ability to decrease emissions due to ruptures or leaks. Although traditionally such detection relies in alarm management system and operator’s expertise, given the system’s nature as large-scale, complex, and with vast amount of information available, such alarm generation is better suited for a fault detection system based on data-driven techniques. This would allow operators and engineers to have a better framework to address the online data being gathered. This paper presents an assessment on multiple fault-case scenarios in critical infrastructure using two different data-driven based fault detection algorithms: Principal component analysis (PCA) and its dynamic variation (DPCA). Both strategies are assessed under fault scenarios related to natural gas transmission systems including pipeline leakage due to structural failure and flow interruption due to emergency valve shut down. Performance evaluation of fault detection algorithms is carried out based on false alarm rate, detection time and misdetection rate. The development of modern alarm management frameworks would have a significant contribution in natural gas transmission systems’ safety, reliability and sustainability.