Transforming the energy sector: the evolution of technological systems in renewable energy technology
This paper analyses the development and diffusion of technologies that utilize renewable energy sources in Germany, Sweden and the Netherlands. The analysis enlarges the life cycle model of industry evolution to one where the focus is on the formation and evolution of new technological systems. Particular focus is on explaining success and failures in shifting from a formative phase into one characterized by positive feedbacks. A set of challenges is identified for policy makers attempting to influence the process of transforming the energy sector. 
The Future of Seawater Desalination: Energy, Technology, and the Environment
In recent years, numerous large-scale seawater desalination plants have been built in water-stressed countries to augment available water resources, and construction of new desalination plants is expected to increase in the near future. Despite major advancements in desalination technologies, seawater desalination is still more energy intensive compared to conventional technologies for the treatment of fresh water. There are also concerns about the potential environmental impacts of large-scale seawater desalination plants. Here, we review the possible reductions in energy demand by state-of-the-art seawater desalination technologies, the potential role of advanced materials and innovative technologies in improving performance, and the sustainability of desalination as a technological solution to global water shortages. 
Geothermal energy technology and current status: an overview
Geothermal energy is the energy contained as heat in the Earth’s interior. This overview describes the internal structure of the Earth together with the heat transfer mechanisms inside mantle and crust. It also shows the location of geothermal fields on specific areas of the Earth. The Earth’s heat flow and geothermal gradient are defined, as well as the types of geothermal fields, the geologic environment of geothermal energy, and the methods of exploration for geothermal resources including drilling and resource assessment. 
Evaluation of Stiffness in Compression Perpendicular to Grain of Brazilian Tropical Wood Species
It is essential to have full knowledge of wood properties, such as strength and stiffness, for the preparation of reliable structural designs. The Brazilian Code ABNT NBR 7190 (1997) establishes that the modulus of elasticity in compression perpendicular to grain (Ec90) can be obtained in a simplified way, in the absence of experimental determination, by means of a correlation with the modulus of elasticity in the direction parallel to grain (Ec0 = 20 Ec90). In order to verify the adequacy of this expression, the results obtained for five species of wood, covering the strength classes assumed by the mentioned Code were analyzed: Cambará Rosa (Erisma sp.), C20; Cedro Amazonense (Cedrella sp.), C30; Cupiúba (Goupia glabra), C40; Itaúba (Mezilaurus itauba), C50; Roxinho (Peltogyne sp.), C60. For each species, from the tests prescribed by ABNT NBR 7190, the elastic moduli were obtained in the directions parallel and normal to grain. In the evaluation of the precision of the proposed estimation, the least squares method was used to determine the coefficient α of the investigated relation. For the data set involving the five species studied, the coefficient resulted in α = 20.64. This value is compatible with the correlation proposed by the Brazilian standard, evidencing its reliability. 
An Evaluation of the Global Potential of Cocoyam (Colocasia and Xanthosoma species) as An Energy Crop
Aims: To evaluate the potential of cocoyam (Colocasia and Xanthosoma species) for the production of ethanol and methane for use as energy sources.
Study design: Laboratory experimentation.
Place and duration of study: Federal College of Agriculture Ibadan and Institute of Agricultural Research and Training (IAR&T), Moor Plantation, Ibadan, Nigeria between December 2010 and June 2011.
Methodology: Five, 15, 25 and 35 kg samples of peeled cocoyam corms were weighed in three replicates. Next, the weighed cocoyam was soaked in clean water for 24 hr, and afterwards placed on a clean tray and allowed to air dry naturally for 4 hr. The cocoyam corms were then cut and the pieces transferred to a mortar where they were mashed to attain sufficient size reduction. The mash was then transferred into a plastic bucket. Five
hundred, 650, 800 and 950 ml of N-hexane (C6H14) was added to the 5, 15, 25 and 35kg samples. The mash was thoroughly stirred to achieve an even mixture with the hexane. It was then covered and left undisturbed in the laboratory at room temperature for 8 days. The fermented mash was poured onto a 0.6 mm aperture size sieve and completely squeezed to dryness while the liquid filtered through the sieve. N-hexane was removed from the filtered liquid. The collected liquid was poured into a glass dish and then gradually heated at 79°C for a total of 10 hr (at intervals of 2 hr heating followed by 1 hr cooling) to ensure complete evaporation of any trapped H2O or CO2 remaining in it. Afterwards the final liquid (ethanol) was allowed to cool normally in the lab and its mass, volume and other properties were measured.
Results: It was found that ethanol was yielded at the rate of 139 L/tonne of cocoyam. Therefore, 10 million tonnes annual global production of cocoyam is potentially able to produce 331 million gallons of ethanol (i.e. 200 million gallons gasoline equivalent) or 39.5 million cubic metres of methane which on burning would produce 179.3 x 107 MJ of energy. The mash obtained as byproduct of the processes is capable of supplying 59 calories of food energy per 100g.
Conclusion: Cocoyam has very good potential as a source of ethanol and methane. Its use as a renewable source of energy for the production of biofuels is recommended and doing so poses no threat to the environment or food supply. The mash produced is an excellent feedstock for livestock. The scientific innovation and relevance of this study lies in the fact that cocoyam is a renewable produce and the fermentation and anaerobic digestion methods used are applicable across countries and regions irrespective of available degree of industrialization and climate. 
 Jacobsson, S. and Bergek, A., 2004. Transforming the energy sector: the evolution of technological systems in renewable energy technology. Industrial and corporate change, 13(5), pp.815-849.
 Elimelech, M. and Phillip, W.A., 2011. The future of seawater desalination: energy, technology, and the environment. science, 333(6043), pp.712-717.
 Barbier, E., 2002. Geothermal energy technology and current status: an overview. Renewable and sustainable energy reviews, 6(1-2), pp.3-65.
 Almeida, A. de, Lanini, T. L., Caetano, J., Christoforo, A. and Lahr, F. (2018) “Evaluation of Stiffness in Compression Perpendicular to Grain of Brazilian Tropical Wood Species”, Current Journal of Applied Science and Technology, 28(5), pp. 1-7. doi: 10.9734/CJAST/2018/42945.
 Adelekan, B. A. (2011) “An Evaluation of the Global Potential of Cocoyam (Colocasia and Xanthosoma species) as An Energy Crop”, Current Journal of Applied Science and Technology, 2(1), pp. 1-15. doi: 10.9734/BJAST/2012/603.