Techno-economic comparative analysis of renewable energy systems: Case study in Zimbabwe

Fluctuations in fossil fuel prices significantly affect the economies of countries, especially oil-importing countries, hence these countries are thoroughly investigating the increase in the utilization of renewable energy resources as it is abundant and locally available in all the countries despite challenges. Renewable energy systems (RES) such as solar and wind systems offer suitable alternatives for fossil fuels and could ensure the energy security of countries in a feasible way. Zimbabwe is one of the African countries that import a significant portion of its energy needs which endanger the energy security of the country. Several studies in the literature discussed the feasibility of different standalone and hybrid RES either with or without energy storage systems to either maximize the technical feasibility or the economic feasibility; however, none of the studies considered maximizing both feasibilities at the same time. Therefore, we present a techno-economic comparison of standalone wind and solar photovoltaic (PV) in addition to hybrid PV/wind systems based on maximizing the RES fraction with levelized cost of electricity (LCOE) being less than or equal to the local grid tariff where Gwanda, Zimbabwe, is the case study. The methodology suggested in this study could increase the utilization of renewable energy resources feasibly and at the same time increase the energy security of the country by decreasing dependency on imported energy. The results indicate that the PV/wind hybrid system does not only have the best economic benefits represented by the net present value (NPV) and the payback period (PBP), but also the best technical performance; where the maximum feasible size of the hybrid system-2 MW wind and 1 MW PV-has RES fraction of 65.07%, LCOE of 0.1 USD/kWh, PBP of 3.94 years, internal rate of return of 14.04% and NPV of 3.06 × 106 USD. Having similar systems for different cities in Zimbabwe will decrease the energy bill significantly and contribute toward the energy security of the country

Internet of Things for Sustainable Forestry

Forests and grasslands play an important role in water and air purification, prevention of the soil erosion, and in provision of habitat to wildlife. Internet of Things has a tremendous potential to play a vital role in the forest ecosystem management and stability. The conservation of species and habitats, timber production, prevention of forest soil degradation, forest fire prediction, mitigation, and control can be attained through forest management using Internet of Things. The use and adoption of IoT in forest ecosystem management is challenging due to many factors. Vast geographical areas and limited resources in terms of budget and equipment are some of the limiting factors. In digital forestry, IoT deployment offers effective operations, control, and forecasts for soil erosion, fires, and undesirable depositions. In this chapter, IoT sensing and communication applications are presented for digital forestry systems. Different IoT systems for digital forest monitoring applications are also discussed

Sizing renewable energy systems with energy storage systems in microgrids for maximum cost-efficient utilization of renewable energy resources

The hybridization of renewable energy systems (RES) and further integrating them with Energy Storage Systems (ESS) can help improve the RESs’ reliability and reduce the mismatch between energy consumption and generation profiles. The main aim of this study is to suggest a sizing methodology for the RES components with various ESS scenarios in a microgrid through techno-economic feasibility analysis. Although the suggested methodology is flexible to include several RESs and ESSs, the methodology is demonstrated to compare the techno-economic performance of Wind and Photovoltaic (PV) energy systems under four different ESS scenarios; (i) no ESS, (ii) Pumped Hydro Storage (PHS), (iii) Hydrogen Fuel Cell (HFC), and (iv) hybrid ESS (PHS/HFC). The optimal RES configuration is determined by maximizing the RES fraction while equating the Cost of Electricity (COE) to the national utility tariff. However, in the event that there is no feasible system configuration that satisfies the mentioned criteria, the main objective becomes maximizing the RES fraction at the lowest attainable COE. This study outlines that the incorporation of PHS and HFC with the PV/Wind hybrid system increased the demand-supply fraction from 46.5%–89.4% and the RES fraction from 62.6%–91.8% with COE equals to 0.175 USD/kWh

Sizing methodology of a PV/wind hybrid system: Case study in cyprus

This study aims to suggest a method for sizing of a photovoltaic (PV)/wind hybrid system based on maximizing the annual renewable energy system (RES) fraction with levelized cost of electricity (LCOE) being equal to the grid tariff. The novelty of this article is the idea of maximizing the energy security, energy localization, and environmental benefits from the hybrid system and at the same time ensures the economic feasibility of the system where Middle East Technical University Northern Cyprus Campus (METU NCC) is the case study of this article. The resultant size of a hybrid system for METU NCC is one 2 MW wind turbine and 760 kW PV power plant with annual RES fraction of 52.96%, LCOE of 0.175 USD/kWh, and a payback period of 9.82 years. Such system will increase the localization of energy and cut the transmission losses and also will contribute in the energy security of the island by reducing the annual fuel consumption of the island by 9920 barrels which will also reduce the annual CO2 emissions by 3622 tons. (c) 2018 American Institute of Chemical Engineers Environ Prog, 38:e13052, 201