Showing papers on "Grid parity published in 2015"

Electrical energy storage systems: A comparative life cycle cost analysis

Abstract: Large-scale deployment of intermittent renewable energy (namely wind energy and solar PV) may entail new challenges in power systems and more volatility in power prices in liberalized electricity markets. Energy storage can diminish this imbalance, relieving the grid congestion, and promoting distributed generation. The economic implications of grid-scale electrical energy storage technologies are however obscure for the experts, power grid operators, regulators, and power producers. A meticulous techno-economic or cost-benefit analysis of electricity storage systems requires consistent, updated cost data and a holistic cost analysis framework. To this end, this study critically examines the existing literature in the analysis of life cycle costs of utility-scale electricity storage systems, providing an updated database for the cost elements (capital costs, operational and maintenance costs, and replacement costs). Moreover, life cycle costs and levelized cost of electricity delivered by electrical energy storage is analyzed, employing Monte Carlo method to consider uncertainties. The examined energy storage technologies include pumped hydropower storage, compressed air energy storage (CAES), flywheel, electrochemical batteries (e.g. lead–acid, NaS, Li-ion, and Ni–Cd), flow batteries (e.g. vanadium-redox), superconducting magnetic energy storage, supercapacitors, and hydrogen energy storage (power to gas technologies). The results illustrate the economy of different storage systems for three main applications: bulk energy storage, T&D support services, and frequency regulation.

Global Prospects, Progress, Policies and Environmental Impact of Solar Photovoltaic Power Generation

Abstract: Global energy demand and environmental concerns are the driving force for use of alternative, sustainable, and clean energy sources. Solar energy is the inexhaustible and CO2-emission-free energy source worldwide. The Sun provides 1.4 � 10 5 TW power as received on the surface of the Earth and about 3.6 � 10 4 TW of this power is usable. In 2012, world power consumption was 17 TW, which is less than 3.6 � 10 4 TW. Photovoltaic (PV) cells are the basic element for converting solar energy into electricity. PV cell technologies, energy conversion efficiency, economic analysis, energy policies, environmental impact, various applications, prospects, and progress have been comprehensively reviewed and presented in this paper. This work compiles the latest literature (i.e. journal articles, conference proceedings, and reports, among others) on PV power generation, economic analysis, environmental impact, and policies to increase public awareness. From the review, it was found that PV is an easy way to capture solar energy where PV based power generation has also rapidly increased.

Photovoltaic and solar power forecasting for smart grid energy management

Abstract: Due to the challenge of climate and energy crisis, renewable energy generation including solar generation has experienced significant growth. Increasingly high penetration level of photovoltaic (PV) generation arises in smart grid. Solar power is intermittent and variable, as the solar source at the ground level is highly dependent on cloud cover variability, atmospheric aerosol levels, and other atmosphere parameters. The inherent variability of large-scale solar generation introduces significant challenges to smart grid energy management. Accurate forecasting of solar power/irradiance is critical to secure economic operation of the smart grid. This paper provides a comprehensive review of the theoretical forecasting methodologies for both solar resource and PV power. Applications of solar forecasting in energy management of smart grid are also investigated in detail.

Pathways for solar photovoltaics

Abstract: Solar energy is one of the few renewable, low-carbon resources with both the scalability and the technological maturity to meet ever-growing global demand for electricity. Among solar power technologies, solar photovoltaics (PV) are the most widely deployed, providing 0.87% of the world's electricity in 2013 and sustaining a compound annual growth rate in cumulative installed capacity of 43% since 2000. Given the massive scale of deployment needed, this article examines potential limits to PV deployment at the terawatt scale, emphasizing constraints on the use of commodity and PV-critical materials. We propose material complexity as a guiding framework for classifying PV technologies, and we analyze three core themes that focus future research and development: efficiency, materials use, and manufacturing complexity and cost.

Low-cost solution to the grid reliability problem with 100% penetration of intermittent wind, water, and solar for all purposes

Abstract: This study addresses the greatest concern facing the large-scale integration of wind, water, and solar (WWS) into a power grid: the high cost of avoiding load loss caused by WWS variability and uncertainty. It uses a new grid integration model and finds low-cost, no-load-loss, nonunique solutions to this problem on electrification of all US energy sectors (electricity, transportation, heating/cooling, and industry) while accounting for wind and solar time series data from a 3D global weather model that simulates extreme events and competition among wind turbines for available kinetic energy. Solutions are obtained by prioritizing storage for heat (in soil and water); cold (in ice and water); and electricity (in phase-change materials, pumped hydro, hydropower, and hydrogen), and using demand response. No natural gas, biofuels, nuclear power, or stationary batteries are needed. The resulting 2050–2055 US electricity social cost for a full system is much less than for fossil fuels. These results hold for many conditions, suggesting that low-cost, reliable 100% WWS systems should work many places worldwide.

A study on global solar PV energy developments and policies with special focus on the top ten solar PV power producing countries

Abstract: The mitigations of global energy demands, climate change and energy related greenhouse gas effects are the most important factors in the modern days. However, renewable energy is one of the alternative sources which has the capacity to mitigate all the above. Among all the renewable energy sources, solar energy is one of the most abundant and the cleanest energy source. Different laboratories of the world have achieved different solar cell efficiencies, which are also discussed in the present paper. This paper presents the global solar PV developments, per capita values, government supportive invectives and policies of the top ten solar power producing countries. This paper also presents the investments of the global solar energy among the countries. Finally, through the study, it is found that these top ten leading countries are following fulfilment of their projections, supportive tariff rates, net metering, green certificates and government incentive policies as their instruments.

Comparison of geothermal with solar and wind power generation systems

Abstract: Geothermal, solar and wind are all clean, renewable energies with a huge amount of resources and a great potential of electricity generation. Geothermal energy had definitely dominated the renewable energy market in terms of the installed electricity power about 30 years ago. The unfortunate fact is that the total installed capacity of geothermal electricity has been eclipsed by solar and wind in recent years. In this paper, benefits of using renewable energy resources (RER) have been summarized and attempt has been made to explain the recent trends causing the shift from geothermal energy to solar and wind. Cost, payback time, size of power generation, construction time, resource capacity, characteristics of resource, and other factors were to compare geothermal, solar, and wind power generation systems. Furthermore, historical data from geothermal, solar, and wind industries were collected and analyzed at the global scale. The data from hydropower were also considered in the comparison. Finally, we proposed suggestions for the geothermal industry to catch up with solar and wind industries.

Solar energy in Iran: Current state and outlook

Abstract: This paper introduces the resource, status and prospect of solar energy in Iran briefly. Among renewable energy sources, Iran has a high solar energy potential. The widespread deployment of solar energy is promising due to recent advancements in solar energy technologies. Therefore, many investors inside and outside the country are interested to invest in solar energy development. Iran’s total area is around 1600,000 km 2 or 1.6×10 12 m 2 with about 300 clear sunny days in a year and an average 2200 kW-h solar radiation per square meter. Considering only 1% of the total area with 10% system efficiency for solar energy harness, about 9 million MW h of energy can be obtained in a day. The government’s goal on 2012 was to install 53,000 MW capacity plants for electricity generation. To reach this goal, it was assumed that the new gas-fired plants along with the hydroelectric and nuclear power generating plants could be financed by independent power producers including those of foreign investment. Based on the fifth 5 year Socio-economic and Cultural Development Plan, the private sector was expected to have a share of at least 270 MW in renewable energy development. The existing small capacity solar energy plants are in Shiraz, Semnan, Taleghan, Yazd, Tehran and Khorasan. Based on the specified available solar trough technology, solar area, average solar hours and average solar direct irradiation, the technical potential of solar electricity was estimated to be 14.7 TWe. Under the current energy policies, the combined solar, wind and geothermal power plants are economically viable. These huge RES’s potential can be realized assuming the availability of technology, investment capital, human expertise and the other resources along with a long-term driven renewable energy policy. Due to high growth rate of electricity demand in Iran, the nominal installed capacity has increased by 8.9% per annum during 2001–2007. In the reference scenario, the share of RES in total installed electricity capacity is expected to be about 2% in 2030. It is expected that the cumulative RES installed capacity will reach 2.8 GW in 2030. This requires more than 2800 million US dollar investment during 2010–2030.

Solar Forecasting: Methods, Challenges, and Performance

Abstract: The deployment of solar-based electricity generation, especially in the form of photovoltaics (PVs), has increased markedly in recent years due to a wide range of factors including concerns over greenhouse gas emissions, supportive government policies, and lower equipment costs. Still, a number of challenges remain for reliable, efficient integration of solar energy. Chief among them will be developing new tools and practices that manage the variability and uncertainty of solar power.

Photovoltaics in Microgrids: An Overview of Grid Integration and Energy Management Aspects

Abstract: The microgrid vision contains several aspects, and a commonly admitted one is a portion of grid with its own means of production and energy flow controls. Photovoltaic (PV) generation is geographically the most distributed means of electricity production. In this sense, the integration of PVs in microgrids seems natural. The intermittency of PV generation can be compensated not only by using energy storage technologies but also by demand-side management and exchanges with other power networks: the main grid and surrounding microgrids. Many aspects still have to be investigated in the fields of power electronics, information communications technologies (ICTs), protections, and power quality (PQ) issues, to make this association a reality.

A Review of Hybrid Solar PV and Wind Energy System

Abstract: Due to the fact that solar and wind power is intermittent and unpredictable in nature, higher penetration of their types in existing power system could cause and create high technical challenges especially to weak grids or stand-alone systems without proper and enough storage capacity. By integrating the two renewable resources into an optimum combination, the impact of the variable nature of solar and wind resources can be partially resolved and the overall system becomes more reliable and economical to run. This paper provides a review of challenges and opportunities / solutions of hybrid solar PV and wind energy integration systems. Voltage and frequency fluctuation, and harmonics are major power quality issues for both grid-connected and stand-alone systems with bigger impact in case of weak grid. This can be resolved to a large extent by having proper design, advanced fast response control facilities, and good optimization of the hybrid systems. The paper gives a review of the main research work reported in the literature with regard to optimal sizing design, power electronics topologies and control. The paper presents a review of the state of the art of both grid-connected and stand-alone hybrid solar and wind systems.

Comparison of Photovoltaic Array Maximum Power Point Tracking Techniques

Abstract: The many different techniques for maximum power point tracking of photovoltaic (PV) arrays are discussed. The techniques are taken from the literature dating back to the earliest methods. It is shown that at least 19 distinct methods(Algo.) have been introduced in the literature, with many variations on implementation. One of the major concerns in the power sector is the day- to-day increasing power demand but the unavailability of enough resources to meet the power demand using the conventional energy sources. Demand has increased for renewable sources of energy to be utilized along with conventional systems to meet the energy demand. Renewable sources like wind energy and solar energy are the prime energy sources which are being utilized in this regard. The continuous use of fossil fuels has caused the fossil fuel deposit to be reduced and has drastically affected the environment depleting the biosphere and cumulatively adding to global warming. Solar energy is abundantly available that has made it possible to harvest it and utilize it properly. Solar energy can be a standalone generating unit or can be a grid connected generating unit depending on the availability of a grid nearby. Thus it can be used to power rural areas where the availability of grids is very low. Another advantage of using solar energy is the portable operation whenever wherever necessary. In order to tackle the present energy crisis one has to develop an efficient manner in which power has to be extracted from the incoming solar radiation. The power conversion mechanisms have been greatly reduced in size in the past few years. The development in power electronics and material science has helped engineers to come up very small but powerful systems to withstand the high power demand. But the disadvantage of these systems is the increased power density. Trend has set in for the use of multi-input converter units that can effectively handle the voltage fluctuations. But due to high production cost and the low efficiency of these systems they can hardly compete in the competitive markets as a prime power generation source. The constant increase in the development of the solar cells manufacturing technology would definitely make the use of these technologies possible on a wider basis than what the scenario is presently. The use of the newest power control mechanisms called the Maximum Power Point Tracking (MPPT) algorithms has led to the increase in the efficiency of operation of the solar modules and thus is effective in the field of utilization of renewable sources of energy. Solar cell operates at very low efficiency and thus a better control mechanism is required to increase the efficiency of the solar cell. In this field researchers have developed what are now called the Maximum Power Point Tracking (MPPT) algorithms.

Realistic and Transparent Optimum Scheduling Strategy for Hybrid Power System

Abstract: This paper addresses the transparent and realistic optimum day-ahead (DA) scheduling for a hybrid power system by explicitly considering the uncertainties The basic components of the hybrid power system include conventional thermal generators, wind farm, and solar photovoltaic (PV) modules A set of batteries is available for energy storage and/or discharge The most critical problem in operating a wind farm or solar PV module is that these renewable energy resources cannot be dispatched in the same manner as conventional plants, because they involve climatic factors such as wind velocity and solar irradiation This paper proposes the optimal scheduling strategy taking into account the impact of uncertainties in wind, solar PV, and load forecasts, and provides the best-fit DA schedule by minimizing both DA and real-time adjustment costs including the revenue from renewable energy certificates This strategy consists of a genetic algorithm (GA)-based scheduling and a two-point estimate-based probabilistic real-time optimal power flow The simulation for the IEEE 30-bus system with the GA and two-point estimate method, and the GA and Monte Carlo simulation have been obtained to test the effectiveness of the proposed scheduling strategy

Day-Ahead Power Output Forecasting for Small-Scale Solar Photovoltaic Electricity Generators

Abstract: Because of the rapid growth of small-scale solar electricity generation over the past few years, forecasting solar power output is becoming more important. However, changes in weather conditions cause solar power generation to be highly volatile. This paper analyses the challenges of solar power forecasting and then presents a similar day-based forecasting tool to do 24-h-ahead forecasting for small-scale solar power output forecasting.

Hybrid Microgrid Model Based on Solar Photovoltaic Battery Fuel Cell System for Intermittent Load Applications

Abstract: Microgrids are a subset of the modern power structure using distributed generation to supply power to communities rather than vast regions. The relatively smaller scale mitigates transmission loss with better control, greater security, increased reliability, and design flexibility. This study explores the modeled performance and cost viability of a hybrid grid-tied microgrid that utilizes the combination of solar photovoltaic (PV), batteries, and fuel cell (FC) systems. The proposed concept highlights that each community home is equipped with more solar PV than is required for normal operation. As the homes are part of a microgrid, excess or unused energy from one home is collected for use elsewhere within the microgrid footprint. The surplus power that would have been discarded becomes a community asset and is used to run intermittent services. The modeled community does not have parking adjacent to each home allowing for the installment of a privately owned slower Level 2 charger. This makes electric vehicle (EV) ownership untenable. Based on this study, an optimum configuration is recommended to provide a Level 3 dc quick charger for an intermittent service. The addition of batteries and FCs is meant to increase load leveling, improved reliability, and instill limited island capability.

Energy Management for Households With Solar Assisted Thermal Load Considering Renewable Energy and Price Uncertainty

Abstract: In this paper, we investigate the energy scheduling problem for a household equipped with a solar assisted heating, ventilation, and air conditioning, and water heating system in the real-time pricing environment. Our objective is to minimize the electricity cost while maintaining user's thermal comfort requirements. We consider different types of loads with different characteristics, detailed modeling of thermal dynamics, and uncertainty in electricity price and solar energy. The advantage of the proposed design lies in the exploitation of the solar assisted thermal system that can flexibly utilize the energy from the solar source or from the grid during low-price periods to support the home hot water demand, user thermal indoor temperature preference while reducing the electricity cost. We present numerical results to illustrate the effectiveness of our proposed design. Specifically, we show that the proposed design can achieve significant cost saving, allow flexible tradeoff between user comfort tolerance and electricity cost reduction, and efficiently adjust the electricity consumption load profile. We also analyze the influence of solar assisted thermal system factors such as the water tank temperature limit, solar collector size, and weather condition on the achievable cost.

Challenges of integrating renewable energy sources to smart grids: A review

Abstract: The deep penetration of renewable energy sources is on the cutting edge of smart grid vision. However, the variability and limited predictability of these sources have brought many technical challenges to grids. Many regulatory communities and system operators in the power sector have established grid codes to ensure proper connection of these renewable sources. This paper investigates the up-to-date methods used to enhance power system performance in the presence of a large share of renewable energy generation. In particular, two areas are addressed; the first is the techniques used for improving the wind and photovoltaic low-voltage ride-through capabilities to meet the required grid codes. The second is the contribution of these sources to the small signal stability of the power system in terms of inter-area oscillation damping.

Chance-Constrained Transmission Switching With Guaranteed Wind Power Utilization

Abstract: Due to the significant variability and uncertainty of wind power over short time scales, high penetration of wind power can be problematic in an electric grid. One of the critical issues is how to keep increasing wind penetration without jeopardizing grid security and reliability. This paper explores the possibility of changing transmission network topology, by transmission switching, to accommodate higher utilization of wind power and reduce the generation costs of thermal units. Considering the uncertainty in wind power output, we use chance constraints to ensure that the wind energy utilized exceeds a minimal usage level at a certain probability. We develop a deterministic approximation approach using sample average approximation and provide a strong extended formulation. Numerical results show the potential benefit the proposed model can achieve.