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Compression ignition engines have wide application in the transportation, agricultural, construction and industrial sectors which are critical for the economic sustainability of any nation. These engines are powered with petroleum diesel which is however, been threatened by the reality of crude oil going into extinction in some couple of years if new reserves are not discovered, and also the need to reduce global warming; a consequence of the effect of its combustion products. Biodiesel is a renewable fuel with similar properties to petroleum diesel, and can be used purely or in blends without the need for modifying the existing engines. The thermal efficiency of an engine is a very important performance indicator, and researchers would stop at nothing to ensure its improvement. The kinematic viscosity is one of the fuel's properties which contribute to an engine thermal efficiency. This work is thus designed to review some past studies on the use of biodiesels and its blends in engines and find a correlation between the kinematic viscosity and the thermal efficiency. A correlation was established to exist between the fuel kinematic viscosity and the engine thermal efficiency.

Biodiesels and Improved combustion chamber design have better in-cylinder air motion which positioned them to offer increased advantages in addressing the major concern of high emission and low thermal efficiency of compression ignition engines. This study therefore investigated the impact of Shea-butter biodiesel and redesigned combustion chamber on the performance and emission characteristics of a compression ignition engine. Biodiesel was prepared from Shea-butter using the standard process. Experiments were conducted on a Yoshita-165F engine operated on a blend of AGO and Shea-butter biodiesel and then Yoshita-165F engine equipped with a truncated cone piston crown with a cone base-angle of 40° modified from the standard piston, operated on a blend of AGO and Shea-butter to determine the engines’ performance characteristics using a TQ TD115 MKH Absorption Dynamometer. The performance and emission characteristic of the engine witnessed an improvement with the use of the truncated cone piston crown with a cone base-angle of 40°. This was also observed with AGO/Shea-butter biodiesel blend as fuel and was particularly well pronounced when utilized as a fuel for the truncated cone piston crown equipped engine. Compression ignition engine equipped with the modified piston and operated on AGO/Shea-butter biodiesel led to improvement in performance.

The growth and industrial advancement of any nation are hampered on constant and sufficient electricity supplies, as there exists a correlation between electricity per capita consumption and the standard of living. The manufacturing industries of Nigeria are in a state of comatose, just as research activities in her ivory towers of learning is at a low state because of the epileptic electricity supply. There are approved licenses for electricity generation to the tune of 26,000 MW as of 2015, and the current available capacity is in excess of 6000 MW of the installed generation capacity of about 12,000 MW. An average of about 4000 MW is what get distributed to the populace partly due to the constraints on the transmission and the distribution network, however, the manufacturing industries demand stands in excess of 13,000 MW. Decentralized generation in line with some of the windows of opportunity provided by the National Electric Regulatory Commission will allow for the supply of the excess generated electricity to the manufacturing industries and higher institutions of learning and encourage generation at full capacity and commissioning of new plants with the provision of conducive environment. The country’s moribund industries will certainly come back to life, and newer ones come into play with constant and adequate supply of electricity, and foster research collaboration with our higher institutions with the attendant positive effect on the nation’s economy.

The future of internal combustion engine-powered automobiles hangs in the balance unless clean fuels are available in commercial quantities. Electricity-powered vehicles will displace the internal combustion engine-powered automobiles. However, electricity-powered vehicles are yet to meet some of the automobile demands. A paradigm shift with attendant infrastructural change is necessary for its adoption. Synthetic fuels promise to be the solution. Their invention dates back to the early twentieth century when the concern was not about climate change. The search for alternative fuels later metamorphosed to when fossil fuels reserve depletion and petroleum derivatives cost became a concern. The alternatives were made available in biofuels. The prevailing challenge is now climate change. It is the consequence of the emission of greenhouse gases from the combustion of petroleum derivatives in automobiles. Synthetic fuels show the potential of coming to the rescue despite the prevailing hurdles. The future holds a potential promise of converting greenhouse gas (CO2) to liquid fuels that will allow little or no disruptions to the current transportation infrastructure network. It is, therefore, necessary to encourage further studies on the production of synthetic fuels. The environmental and economic benefits of commercially available synthetic fuels promise to be enormous.

The importance of brake systems in automobiles cannot be overemphasized. Brakes are used in speed control of vehicles and do so by the conversion of kinetic energy into thermal energy. Better stopping performance has favored the disc brake system over the drum brake system and has found wide application in high-performance vehicles. Brake fade, caused by thermal overload has placed a limit on the permissible temperature at which braking systems can function, and it is the task of designers to ensure that this is avoided. However, even with a good design, panic braking at high speeds could lead to high-temperature values. This study is thus undertaken to numerically investigate the effect of selected braking patterns on temperature growth which could lead to brake fade in a disc brake system for a 2 200 kg car moving at a velocity of 40 m/s whose velocity is expected to be reduced to 4 m/s after five seconds with two matches of the brake for a seconds' interval. The peak temperature attained in the system during braking was observed to be different for the different braking patterns, and the best-suited pattern was the 1s-1s-3s with peak temperature values below 600 K.

 Electricity generation pose an impact on the environment.  The use of fossils for electricity generation contributes to GHG emissions.  Reducing GHG emissions requires a shift to electricity generation from renewables.  Climate change can affect the efficiency of renewable electricity generation.  Renewable electricity generated synthetic fuels can be used during harsh conditions.Human actions such as electricity generation are contributory causes of climate change. In a quest to reduce the emission of greenhouse gases associated with electricity generation from fossil fuels, the world is turning to renewables. Renewable sources, however, also do have an impact on the environment. Likewise, renewable electricity generation is also dependent on the climate. Hydro, Wind, and Solar are the popular renewable energy sources for the generation of electricity. This work reviews the impact of these renewables in electricity generation on the environment. It also considers the effect of climate change on its use. The construction of renewable electricity generating plants leads to habitat disruptions and can also cause fatalities. Climate change weighs an enormous impact on the performance of renewable electricity generating plants. The recent blackout experienced in Texas as a result of the cold weather is a good example. The end of extreme weather conditions is not yet, and the need to start preparing to prevent a blackout re-occurrence. A possible solution for sustainable renewable electricity generation in extreme weather conditions lies in synthetic fuel availability.