• Energy Research

The first part of the current review highlights the evolutionary nuances and research hotspots in the field of nanoparticles in low carbon fuels. Our findings reveal that contribution to the field is largely driven by researchers from Asia, mainly India. Of the three biofuels under review, biodiesel seems to be well studied and developed, whereas studies regarding vegetable oils and alcohols remain relatively scarce. The second part also reviews the application of nanoparticles in biodiesel/vegetable oil/alcohol-based fuels holistically, emphasizing fuel properties and engine characteristics. The current review reveals that the overall characteristics of the low carbon fuel–diesel blends improve under the influence of nanoparticles during combustion in diesel engines. The most important aspect of nanoparticles is that they act as an oxygen buffer that provides additional oxygen molecules in the combustion chamber, promoting complete combustion and lowering unburnt emissions. Moreover, the nanoparticles used for these purposes exhibit excellent catalytic behaviour as a result of their high surface area-to-volume ratio—this leads to a reduction in exhaust pollutants and ensures an efficient and complete combustion. Beyond energy-based indicators, the exergy, economic, environmental, and sustainability aspects of the blends in diesel engines are discussed. It is observed that the performance of the diesel engine fuelled with low carbon fuels according to the second law of efficiency improves under the influence of the nano-additives. Our final part shows that despite the benefits of nanoparticles, humans and animals are under serious threats from the highly toxic nature of nanoparticles.

Abstract Increasing cost of generating energy through conventional sources coupled with environmental pollution concerns has led to the need to find more sustainable, clean and cheaper sources of energy generation. This paper evaluates two forms of energy: nuclear and solar energy for developing countries with a case study on Ghana. The research found out that Ghana like other several other developing countries have the opportunity to reduce their cost of electricity significantly should any of the under studied technologies be deployed. Obtained LCOE for the 20 MW modelled Solar power plant (SPP) in Navrongo ranges between 5.74 and 9.41 ¢/kWh for real discount and annual interest rates ranging between 1 and 25%. LCOEs of 125.53–125.55 $/MWh for discount rates between 3% and 15%, respectively were obtained for the 1200 MW nuclear power plant (NPP) expected to be constructed in Ghana. The research concluded with a suggestion that since the NPP project is capital intensive, development of SPP should be given the needed attention in the short to medium term to help build a resilient economy upon which NPP can be considered in the long term. Some financing models were also suggested for the construction of such capital-intensive projects.

China intends to develop its renewable energy sector in order to cut down on its pollution levels. Concentrated solar power (CSP) technologies are expected to play a key role in this agenda. This study evaluated the technical and economic performance of a 100 MW solar tower CSP in Tibet, China, under different heat transfer fluids (HTF), i.e., Salt (60% NaNO3 40% KNO3) or HTF A, and Salt (46.5% LiF 11.5% NaF 42% KF) or HTF B under two different power cycles, namely supercritical CO2 and Rankine. Results from the study suggest that the Rankine power cycle with HTF A and B recorded capacity factors (CF) of 39% and 40.3%, respectively. The sCO2 power cycle also recorded CFs of 41% and 39.4% for HTF A and HTF B, respectively. A total of 359 GWh of energy was generated by the sCO2 system with HTF B, whereas the sCO2 system with HTF A generated a total of 345 GWh in the first year. The Rankine system with HTF A generated a total of 341 GWh, while the system with B as its HTF produced a total of 353 GWh of electricity in year one. Electricity to grid mainly occurred between 10:00 a.m. to 8:00 p.m. throughout the year. According to the results, the highest levelized cost of energy (LCOE) (real) of 0.1668 USD/kWh was recorded under the Rankine cycle with HTF A. The lowest LCOE (real) of 0.1586 USD/kWh was obtained under the sCO2 cycle with HTF B. In general, all scenarios were economically viable at the study area; however, the sCO2 proved to be more economically feasible according to the simulated results.

Abstract Ghana is endowed with lot of potentials in the renewable energy sector which are yet to be fully exploited. This research evaluated the techno-economic potentials of PV-Wind-DG-Battery and Wind-DG- Battery hybrid power plants in the southern part of Ghana in a town call Mankwadze to ascertain the bankability of the two systems for large-scale commercial electricity generation. The levelized cost of energy (LCOE) and net present cost (NPC) metrics were used in the economic analysis of the modelled power plants. The LCOE and NPC of the two systems were estimated at 0.382 $/kWh and $8,649,054 for the PV-Wind-DG-Battery system, respectively, whiles the Wind-DG-Battery system also recorded 0.396 $/kWh and $8,966,700 for the LCOE and NPC, respectively. The base case (generator) recorded an LCOE of 0.412 $/kWh and an OC of $345,998 with an initial cost of $454,256. The obtained results are all relatively higher than the current cost of energy for household consumers in Ghana, but a sensitivity analysis showed that the LCOEs can be reduced when certain parameters such as cost of fuel, discount and inflation rates are varied. This suggests that such projects can be done when the necessary investment climate is created by those in authority.

Abstract This paper presents a new approach for identifying and site contour optimization of wind farms in the context of transmission expansion planning for the Republic of Ghana to support its renewable energy development plan. The proposed approach uses spatial multi-criteria analysis, density-based clustering, and analytical hierarchy process to identify, optimize, and rank candidate sites. The proposed methodology provides an automated procedure for optimizing site boundary contours using density-based clustering. It provides decisional flexibility in identifying clusters of the minimum required size, unlike the traditional approach. The analysis identifies 14 geographical clusters with high wind energy availability with an average area of 19 km2 and a maximum area of up to 32 km2. All the clusters found are in relative proximity to both transportation and transmission networks. Results from the techno-economic and environmental assessment identified the least levelized cost of energy of 0.21 $/kW h at clusters C, E, M and N. The power plant modeled at cluster M recorded the least simple payback period of 4.30 years and highest internal rate of return of 22.8 %. The worst site was cluster L because it recorded the highest emissions of about 354,474 kg/year for carbon dioxide and 130 kg/year for carbon monoxide.

Power distribution to decentralized and remote communities secluded from centralized grid connections has always been a problem for utilities and governments worldwide. This situation is even more critical for the isolated communities in Russia due to the vast nature of the country. Therefore, the Russian government is formulating and implementing several strategies to develop its renewable energy sector. However, very little information is available on the possible performance of solar photovoltaic (PV) modules under Russian weather conditions for all year round. Thus, this study has been designed to fill that research gap by assessing the performance ratio (PR), degradation, energy loss prediction, and employment potential of PV modules in the Sverdlovsk region of Russia using the PVsyst simulation model. A side-by-side comparison of the fixed tilted plane and tracking horizontal axis East–West were analyzed. According to the results, the annual production probability (P) for the fixed PV module for a P50, P75, and P90 is 39.68 MWh, 37.72 MWh, and 35.94 MWh, respectively, with a variability of 2.91 MWh. In the case of the tracking PV module, the annual production probability for the P50, P75, and P90 is 43.18 MWh, 41.05 MWh, and 39.12 MWh, respectively, with a variability of 3.17 MWh. A PR of 82.3% and 82.6% is obtained for the fixed and tracking systems, respectively, while the PV array losses for the fixed and tracking orientations are 15.1% and 14.9%, respectively. The months of May to August recorded the highest array losses due to the high temperatures that are usually recorded within that period.

In recent time, Bhutan as a small landlocked nation between China in the north and India in the south started to experience a gap in hydro electricity supply and demand. To address the growing electricity demand in the country, solar energy can be a diversification of Bhutan's renewable energy to address domestic energy security and global environmental concerns. In this paper, efforts have been made to assess the future energy potential from the rooftop solar photovoltaic (PV) systems in Thimphu City. For this study, we designed and simulated a 12 kWp grid-tied solar PV systems using PVSYST software. The result showed the annual solar energy generation, final energy yield and performance ratio (PR) of 19,336 kWh, 4.63 kWh/kWp and 84 % respectively. The estimated final energy yield and PR aligned with findings from countries like Saudi Arabia, India, and Pakistan, highlighting the strong solar energy potential in Thimphu. In addition, we conducted simple scenario analysis for energy generation potential when PV systems are installed on 90 %, 75 %, and 50 % of the available building rooftops in Thimphu City. The additional annual solar energy injected into the grid during lean hydropower generation periods was 61 GWh, 51 GWh, and 34 GWh for the three scenarios, respectively. Furthermore, the projected annual cost savings on electricity imports from additional energy generation from grid-tied rooftop solar PV systems was $3.23 million, $2.70 million, and $1.80 million across the three scenarios, using import price figure of 2023. Additionally, installing 12 kWp PV systems on 50 % of building rooftops in Thimphu City alone could result in environmental cost savings of $1.91 million during periods of low hydropower generation. The study is expected to benefit the government agencies, other institutions and individuals interested in solar energy generation using solar PV technology.

Despite the enormous renewable energy (RE) resources available in Ghana, the country has not seen much development and investments in the sector. Therefore, the government has committed to increasing the share of RE in the country’s electricity generation mix to some 10% by 2030. However, this cannot be achieved without the Ghanaian people’s support since the RE sector is capital intensive and requires both public and private sector participation. This study was conducted to evaluate RE’s social acceptance among Ghanaian people using the ordered logit regression model. A total of 999 valid questionnaires out of 1020 distributed questionnaires were considered for the study. The five-point Likert scale was employed to rank their willingness to accept (WTA) RE. From the results, it was observed that there is a general sense of acceptance of renewable energy among Ghanaians. However, the level of acceptance varies from one respondent to another. The study observed that a majority of the respondents (i.e., approximately 45.65%) agree to their WTA renewable energy, while 36.04% strongly agree. The results also indicate that while 6.21% and 0.3% disagree and strongly disagree, 11.81% of the respondents were indifferent regarding their willingness to accept renewable energy development and utilization in Ghana.