Stakeholders’ perspectives on barriers to remote wind–diesel power plants in Canada

Canada has been experimenting with wind–diesel hybrid systems for its remote communities for over 25 years with limited success. This paper discusses the results of a year-long survey that was distributed to stakeholders in wind–diesel systems in remote Canadian communities. These stakeholders include utilities, wind energy technology manufacturers, project developers, researchers, and governments. The analysis shows that there is a strong agreement that capital and operating costs are the most significant barriers to the implementation of wind–diesel systems and that direct project financial incentives, notably production and capital cost incentives designed to reduce these costs are perceived as the most effective way to encourage development. There is a notable disagreement between utilities and governments on one hand, who are split as to the current technical viability of wind–diesel systems, and manufacturers, developers, and researchers on the other, who overwhelmingly believe that wind–diesel systems are mature enough for remote applications.     

Review of research on autonomous wind farms and solar parks and their feasibility for commercial loads in hot regions

In the wake of rising cost of oil and fears of its exhaustion coupled with increased pollution, the governments world-wide are deliberating and making huge strides to promote renewable energy sources such as solar–photovoltaic (solar–PV) and wind energy. Integration of diesel systems with hybrid wind–PV systems is pursued widely to reduce dependence on fossil-fuel produced energy and to reduce the release of carbon gases that cause global climate change. Literature indicates that commercial/residential buildings in the Kingdom of Saudi Arabia (KSA) consume an estimated 10–40% of the total electric energy generated. The study reviews research work carried out world-wide on wind farms and solar parks. The work also analyzes wind speed and solar radiation data of East-Coast (Dhahran), KSA, to assess the technical and economic potential of wind farm and solar PV park (hybrid wind–PV–diesel power systems) to meet the load requirements of a typical commercial building (with annual electrical energy demand of 620,000 kWh). The monthly average wind speeds range from 3.3 to 5.6 m/s. The monthly average daily solar global radiation ranges from 3.61 to 7.96 kWh/m². The hybrid systems simulated consist of different combinations of 100 kW wind machines, PV panels, supplemented by diesel generators. NREL (and HOMER Energy's) HOMER software has been used to perform the techno-economic study. The simulation results indicate that for a hybrid system comprising of 100 kW wind capacity (37 m hub-height) and 40 kW of PV capacity together with 175 kW diesel system, the renewable energy fraction (with 0% annual capacity shortage) is 36% (24% wind + 12% PV). The cost of generating energy (COE, $/kWh) from this hybrid wind–PV–diesel system has been found to be 0.154 $/kWh (assuming diesel fuel price of 0.1$/L). The study exhibits that for a given hybrid configuration, the number of operational hours of diesel generators decreases with increase in wind farm and PV capacity. Attention has also been focused on wind/PV penetration, un-met load, excess electricity generation, percentage fuel savings and reduction in carbon emissions (relative to diesel-only situation) of different hybrid systems, cost break-down of wind–PV–diesel systems, COE of different hybrid systems, etc.     

Cost–benefit analysis of remote hybrid wind–diesel power stations: Case study Aegean Sea islands

More than one third of world population has no direct access to interconnected electrical networks. Hence, the electrification solution usually considered is based on expensive, though often unreliable, stand-alone systems, mainly small diesel-electric generators. Hybrid wind–diesel power systems are among the most interesting and environmental friendly technological alternatives for the electrification of remote consumers, presenting also increased reliability. More precisely, a hybrid wind–diesel installation, based on an appropriate combination of a small diesel-electric generator and a micro-wind converter, offsets the significant capital cost of the wind turbine and the high operational cost of the diesel-electric generator. In this context, the present study concentrates on a detailed energy production cost analysis in order to estimate the optimum configuration of a wind–diesel-battery stand-alone system used to guarantee the energy autonomy of a typical remote consumer. Accordingly, the influence of the governing parameters—such as wind potential, capital cost, oil price, battery price and first installation cost—on the corresponding electricity production cost is investigated using the developed model. Taking into account the results obtained, hybrid wind–diesel systems may be the most cost-effective electrification solution for numerous isolated consumers located in suitable (average wind speed higher than 6.0 m/s) wind potential regions.     

The economics of hybrid power systems for sustainable desert agriculture in Egypt

Egypt has embarked on an ambitious desert land reclamation program in order to increase total food production. Energy planners for these desert agriculture locations have chosen diesel generation power technology because minimization of the initial capital cost of a power supply system is their top priority. This heavy reliance on diesel generation has negative effects on the surrounding environment including soil, groundwater, and air pollution. Although good solar and wind resource prospects exist for the use of cleaner hybrid power systems in certain desert locations, little research has been done to investigate the economic potential of such systems in Egypt’s desert agriculture sector. Using optimization software, we assess the economics of hybrid power systems versus the present diesel generation technology in a remote agricultural development area. We also consider the emission reduction advantages of using hybrid systems. Interestingly enough, optimization results show that hybrid systems are less costly than diesel generation from a net present cost perspective even with the high diesel fuel price subsidies. Since hybrids are also more environmentally friendly, they represent a strong step towards achieving sustainable desert agriculture.     

Techno-economic feasibility of photovoltaic,wind, diesel and hybrid electrification systems for off-grid rural electrification in Colombia

Electrification to rural and remote areas with limited or no access to grid connection is one of the most challenging issues in developing countries like Colombia. Due to the recent concerns about the global climatic change and diminishing fuel prices, searching for reliable, environmental friendly and renewable energy sources to satisfy the rising electrical energy demand has become vital. This study aims at analyzing the application of photovoltaic (PV) panels, wind turbines and diesel generators in a stand-alone hybrid power generation system for rural electrification in three off-grid villages in Colombia with different climatic characteristics. The areas have been selected according to the “Colombia’s development plan 2011–2030 for non-conventional sources of energy”. First, different combinations of wind turbine, PV, and diesel generator are modeled and optimized to determine the most energy-efficient and cost-effective configuration for each location. HOMER software has been used to perform a techno-economic feasibility of the proposed hybrid systems, taking into account net present cost, initial capital cost, and cost of energy as economic indicators.     

风/光/柴多能互补发电系统优化配置研究

为实现风/光/柴多能互补发电系统的经济运行,应用启发式算法以分布式发电投资、运行费用、向输电系统直接购电费用以及考虑环境因素费用总和最小为优化目标,分别对并网型和离网型两种情况进行规划和运行的综合分析,从而确定各DG类型的最优投入容量。研究结果表明:该模型可以全面评估分布式发电的经济性能,并对不同运行方式给出相应的最优配置方案,从而极大地提高系统的供电可靠性和经济可行性。     

Techno-economical analysis of off-grid hybrid systems at Kutubdia Island,Bangladesh

Kutubdia is an island in the southern coast of Bangladesh where mainland grid electricity is not present or would not feasible in near future. Presently, electricity is generated using a diesel generator by Bangladesh Power Development Board (BPDB) for a limited time and location. Due to its remote location, the fuel cost in Kutubdia is very expensive. In the present study one-year recorded wind by Bangladesh Centre of Advanced Studies (BCAS) location and other three potential locations for hybrid system analysis is discussed. The system configuration of the hybrid is achieved based on a theoretical domestic load at the island. The sizing of the hybrid power systems is discussed with 0% and 5% annual capacity of shortage. This feasibility study indicates that wind–PV–diesel system is feasible with 0% capacity of shortage and wind–diesel system is feasible with 5% annual capacity of shortage at all locations. As 5% annual capacity of shortage can be considered, the wind–diesel hybrid system will reduce net present cost as well as cost of energy to about 20% and the diesel consumption on the island can be reduced to about 50% of its present annual consumption. Such a hybrid system will reduce about 44% green house gases (GHG) from the local atmosphere.     

Current status of research on optimum sizing of stand-alone hybrid solar–wind power generation systems

Solar and wind energy systems are omnipresent, freely available, environmental friendly, and they are considered as promising power generating sources due to their availability and topological advantages for local power generations. Hybrid solar–wind energy systems, uses two renewable energy sources, allow improving the system efficiency and power reliability and reduce the energy storage requirements for stand-alone applications. The hybrid solar–wind systems are becoming popular in remote area power generation applications due to advancements in renewable energy technologies and substantial rise in prices of petroleum products. This paper is to review the current state of the simulation, optimization and control technologies for the stand-alone hybrid solar–wind energy systems with battery storage. It is found that continued research and development effort in this area is still needed for improving the systems’ performance, establishing techniques for accurately predicting their output and reliably integrating them with other renewable or conventional power generation sources.     

Hybrid (solar and wind) energy system for Al Hallaniyat Island electrification

Wind–PV–diesel hybrid power generation system technology is a promising energy option since it provides opportunities for developed and developing countries to harness naturally available, inexhaustible and pollution-less resources. The aim of this study is to assess the techno-economic feasibility of utilizing a hybrid wind–PV–diesel power system to meet the load of Al Hallaniyat Island. Hybrid Optimization Model for Electric Renewables software has been employed to carry out the present study. The simulation results indicate that the cost of generating energy (COE) is $0.222 kWh^?1 for a hybrid system composed of a 70 kW PV system, 60 kW wind turbine and batteries together with a 324.8 kW diesel system. Moreover, using the same system but without batteries will increase the COE to $0.225 kWh^?1, the fuel consumption, the excess energy and the total operating hours for the diesel generators. The PV–wind hybrid option is techno-economically viable for rural electrification.     

Canadian remote community power generation: How reformer and fuel cell systems compare with diesel generators

More than three quarters of Canadian remote communities rely solely on diesel generators for electricity generation. The diesel dependency of remote communities has inflated local per capita greenhouse gas emissions and resulted in rising and inconsistent electricity prices that have made community viability reliant on government subsidies. As the diesel generators approach the end of their lifespan replacement, technologies must be considered that will help transition Canadian remote communities from diesel to renewables. Replacing diesel generators with steam reformer and solid oxide fuel cell systems would allow for more efficient diesel generation and would benefit the future implementation of renewable power. A model was generated in Honeywell's UniSim Design Suite to simulate the performance of a diesel fed steam reformer and solid oxide fuel cell system. System operating parameters in the model were optimized to minimize the expected payback period. The system model outputs were compared with expected diesel generator performance for a test case remote community. The test community demonstrated that replacing diesel generators with the proposed steam reformer and solid oxide fuel cell system would result in annual net efficiency improvements of 32%. The efficiency improvement could potentially translate to reductions in carbon dioxide equivalents of over 258 kt and 20‐year savings of over $450 million if all diesel‐reliant Canadian remote communities switched to steam reformer and solid oxide fuel cell systems. In addition to immediate environmental and economic savings, the improved low load performance of the reformer and fuel cell system would allow for the future integration of renewable energy to create highly efficient diesel‐renewable hybrid power plants.     

Study and design of a hybrid wind–diesel-compressed air energy storage system for remote areas

Remote areas around the world predominantly rely on diesel-powered generators for their electricity supply, a relatively expensive and inefficient technology that is responsible for the emission of 1.2 million tons of greenhouse gas (GHG) annually, only in Canada [1]. Wind–diesel hybrid systems (WDS) with various penetration rates have been experimented to reduce diesel consumption of the generators. After having experimented wind–diesel hybrid systems (WDS) that used various penetration rates, we turned our focus to that the re-engineering of existing diesel power plants can be achieved most efficiently, in terms of cost and diesel consumption, through the introduction of high penetration wind systems combined with compressed air energy storage (CAES). This article compares the available technical alternatives to supercharge the diesel that was used in this high penetration wind–diesel system with compressed air storage (WDCAS), in order to identify the one that optimizes its cost and performances. The technical characteristics and performances of the best candidate technology are subsequently assessed at different working regimes in order to evaluate the varying effects on the system. Finally, a specific WDCAS system with diesel engine downsizing is explored. This proposed design, that requires the repowering of existing facilities, leads to heightened diesel power output, increased engine lifetime and efficiency and to the reduction of fuel consumption and GHG emissions, in addition to savings on maintenance and replacement cost.     

The utility of energy storage to improve the economics of wind–diesel power plants in Canada

Wind energy systems have been considered for Canada's remote communities in order to reduce their costs and dependence on diesel fuel to generate electricity. Given the high capital costs, low-penetration wind–diesel systems have been typically found not to be economic. High-penetration wind–diesel systems have the benefit of increased economies of scale, and displacing significant amounts of diesel fuel, but have the disadvantage of not being able to capture all of the electricity that is generated when the wind turbines operate at rated capacity.Two representative models of typical remote Canadian communities were created using HOMER, an NREL micro-power simulator to model how a generic energy storage system could help improve the economics of a high-penetration wind–diesel system. Key variables that affect the optimum system are average annual wind speed, cost of diesel fuel, installed cost of storage and a storage systems overall efficiency. At an avoided cost of diesel fuel of 0.30 $Cdn/kWh and current installed costs, wind generators are suitable in remote Canadian communities only when an average annual wind speed of at least 6.0 m/s is present. Wind energy storage systems become viable to consider when average annual wind speeds approach 7.0 m/s, if the installed cost of the storage system is less than 1000 $Cdn/kW and it is capable of achieving at least a 75% overall energy conversion efficiency. In such cases, energy storage system can enable an additional 50% of electricity from wind turbines to be delivered.     

Assessing the potential for a wind power incentive for remote villages in Canada

This paper discusses the uptake potential for a wind–diesel production incentive designed specifically for Canadian northern and remote communities. In spite of having over 300 remote communities with extremely high electricity costs, Canada has had little success in developing remote wind energy projects. Most of Canada’s large-scale wind power has been developed as a direct result of a Federal production incentive implemented in 2002. Using this incentive structure as a successful model, this paper explores how an incentive tailored to remote wind power could be deployed. Micro-power simulations were done to demonstrate that the production incentive designed by the Canadian Wind Energy Association would cost on average $4.7 $Cdn million and could be expected to result in 14.5 MW of wind energy projects in remote villages in Canada over a 10 year period, saving 11.5 $Cdn million dollars in diesel costs annually, displacing 7600 tonnes of CO_2eq emissions and 9.6 million litres of diesel fuel every year.     

An investigation of variable speed operation of diesel generators in hybrid energy systems

This paper provides a preliminary assessment of the performance and economic potential of a hybrid energy system (wind/diesel) power system which includes a variable speed diesel generator. Recent development in power electronics would be utilized to allow asynchronous operation of the diesel generator, while simultaneously delivering constant frequency electric power to the local electrical grid. In addition to the variable speed diesel, the system can include wind and/or solar electric sources. A hybrid energy system model recently developed at the University of Massachusetts is used to simulate this system configuration and other more conventional wind/diesel hybrid energy systems. Experimental data from a series of variable speed diesel generator tests were used to generate a series of fuel consumption curves used in the analytical model. In addition to performance (fuel savings) comparisons for fixed and variable speed systems, economic cost of energy calculations for the various system designs are presented. It is shown that the proposed system could offer both performance and economic advantages.     

A current and future state of art development of hybrid energy system using wind and PV-solar: A review

The wind and solar energy are omnipresent, freely available, and environmental friendly. The wind energy systems may not be technically viable at all sites because of low wind speeds and being more unpredictable than solar energy. The combined utilization of these renewable energy sources are therefore becoming increasingly attractive and are being widely used as alternative of oil-produced energy. Economic aspects of these renewable energy technologies are sufficiently promising to include them for rising power generation capability in developing countries. A renewable hybrid energy system consists of two or more energy sources, a power conditioning equipment, a controller and an optional energy storage system. These hybrid energy systems are becoming popular in remote area power generation applications due to advancements in renewable energy technologies and substantial rise in prices of petroleum products. Research and development efforts in solar, wind, and other renewable energy technologies are required to continue for, improving their performance, establishing techniques for accurately predicting their output and reliably integrating them with other conventional generating sources. The aim of this paper is to review the current state of the design, operation and control requirement of the stand-alone PV solar–wind hybrid energy systems with conventional backup source i.e. diesel or grid. This Paper also highlights the future developments, which have the potential to increase the economic attractiveness of such systems and their acceptance by the user.     

Use of renewable sources of energy in Mexico case: San Antonio AguaBendita

This paper presents a project undertaken in Mexico to electrify the remote village of San Antonio Agua Bendita (SAAB) using a custom designed hybrid power system. The hybrid power system will provide grid quality electricity to this community which would otherwise not have been electrified via traditional distribution lines. The hybrid power system was designed to electrify the entire community, incorporate multiple sources of renewable power with on-demand power, operate autonomously, and be cost effective in dollars per watt of electricity generated over the system's usable life. A major factor in the success of this project is the use of renewable energy for economic development and community partnership. Many rural electrification projects have provided power for domestic use but few have successfully provided power to improve the economic condition of the people served by the system. The SAAB hybrid avoids this pitfall by providing 120 VAC power at 60 Hz to anticipated industrial loads in the village, as well as providing grid quality power for domestic use. The system consists of the following modules: a controller, battery storage, a PV array, two 1O kW wind turbines, a diesel generator, a micro-hydro generater, power output control     

Economic analysis of PV/diesel hybrid system with flywheel energy storage

This paper analyzes a hybrid energy system performance with photovoltaic (PV) and diesel systems as the energy sources. The hybrid energy system is equipped with flywheel to store excess energy from the PV. HOMER software was employed to study the economic and environmental benefits of the system with flywheels energy storage for Makkah, Saudi Arabia. The analysis focused on the impact of utilizing flywheel on power generation, energy cost, and net present cost for certain configurations of hybrid system. Analyses on fuel consumption and carbon emission reductions for the system configurations were also presented in this paper.     

Techno-economic viability of three different energy-supplying options for remote area electrification in India

Distributed power generation based on renewable energy sources brings new life and hope to electrify remote villagers. The proposed work suggests the techno-economic feasibility of three different energy-supplying alternatives namely the solar photovoltaic (SPV) system, diesel generator system and extending the grid connection for energy supply to a remote village located around 15 km away from the place where grid supply is available. Design of all the above three systems along with their economic analysis is carried out in this paper. A comparison on the basis of economic indicators like unit cost of electricity, net present value and payback period among the three systems is also discussed. The results show that the SPV system is economically more viable among the three options apart from environment benefits. This study may provide a new direction for energy planners to supply energy in remote non-electrified areas of India through SPV systems.     

Pre-feasibility study of stand-alone hybrid energy systems for applications in Newfoundland

A potential solution for stand-alone power generation is to use a hybrid energy system in parallel with some hydrogen energy storage. In this paper, a pre-feasibility study of using hybrid energy systems with hydrogen as an energy carrier for applications in Newfoundland, Canada is explained. Various renewable and non-renewable energy sources, energy storage methods and their applicability in terms of cost and performance are discussed. HOMER is used as a sizing and optimization tool. Sensitivity analysis with wind speed data, solar radiation level, diesel price and fuel cell cost was done. A remote house having an energy consumption of 25 kW h/d with a 4.73 kW peak power demand was considered as the stand-alone load. It was found that, a wind–diesel–battery hybrid system is the most suitable solution at present. However, with a reduction of fuel cell cost to 15% of its current value, a wind–fuel cell system would become a superior choice. Validity of such projection and economics against conventional power sources were identified. Sizing, performance and various cost indices were also analyzed in this paper.     

Assessment of economic viability for PV/wind/diesel hybrid energy system in southern Peninsular Malaysia

This paper analyzed the potential implementation of hybrid photovoltaic (PV)/wind turbine/diesel system in southern city of Malaysia, Johor Bahru. HOMER (hybrid optimization model for electric renewable) simulation software was used to determine the technical feasibility of the system and to perform the economical analysis of the system. There were seven different system configurations, namely stand-alone diesel system, hybrid PV–diesel system with and without battery storage element, hybrid wind–diesel system with and without battery storageelement, PV–wind–diesel system with and without storage element, will be studied and analyzed. The simulations will be focused on the net present costs, cost of energy, excess electricity produced and the reduction of CO₂ emission for the given hybrid configurations. At the end of this paper, PV–diesel system with battery storage element, PV–wind–diesel system with battery storage element and the stand-alone diesel system were analyzed based on high price of diesel.