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Ancillary services are becoming an indispensable tool for maintaining power grid stability due to the increasing adoption of renewable energy resources, many of which (e.g., wind and solar power) are inherently variable. Some energy resources, such as electric vehicles (EVs), have a significant potential for providing their own ancillary services and creating ancillary service markets in smart electric grids. The installation convenience of EVs and plug-in hybrid vehicles (PHVs) has made them the target of many studies. In previous works, the grid-integrated-vehicle (GIV) mechanisms are recognized as a suitable approach to exploit EVs and PHVs for ancillary service markets, particularly regulation markets, which require fast responses. It is important to consider individual consumption behavior (e.g., vehicle usage and energy consumption) in selecting optimal operational points of EV and PHV for maximizing resource effectiveness and user profit. There is, however, currently no mechanism that takes the individual consumption behavior of market participants into account. In this article, a new vehicle-to-home (V2H) aggregator is proposed, which allows individuals to participate in a regulation market using the in-vehicle batteries of their EVs or PHVs. The results show that the proposed V2H aggregator can successfully supply predictable power to the power grid and maximize the profits of individual market participants. Note to Practitioners—This article proposes an architecture of home energy management systems (HEMSs) with electric vehicles (EVs) and plug-in hybrid vehicles (PHVs) to participate in a regulation market using the in-vehicle batteries. Ancillary services are the mechanism for the power grid to ensure the quality of electricity. The proposed architecture is composed of two stages: 1) calculation of the charge and discharge profiles considering minimizing the electricity charge at home and maximizing the capacity to provide for ancillary services and 2) real-time control of charging and discharging the in-vehicle batteries to follow the regulation signal provided from the manager of ancillary services. The simulation result shows the estimated benefit of the aggregator obtained by the trade in the market and the precision of HEMSs’ charging and discharging to follow the request signal. [ABSTRACT FROM AUTHOR]

Vehicle-grid integration (VGI) describes various approaches to link the electric power system and the transportation system in ways that may benefit both. VGI includes systems that treat plug-in electric vehicles (PEVs) as controllable load with a unidirectional flow of electricity, such as 'smart' or 'controlled' charging or time-of-use (TOU) pricing. VGI typically encompasses vehicle-to-grid (V2G), a more technically advanced vision with bidirectional flow of electricity between the vehicle and power grid, in effect treating the PEV as a storage device. Such VGI systems could help decarbonize transportation, support load balancing, integrate renewable energy into the grid, increase revenues for electricity companies, and create new revenue streams for automobile owners. This review introduces various aspects and visions of VGI based on a comprehensive review. In doing so, it identifies the possible benefits, opportunities, and barriers relating to V2G, according to technical, financial, socio-environmental, and behavioral components. After summarizing our sociotechnical approach and the various opportunities and barriers indicated by existing literature, we construct a proposed research agenda to provide insights into previously understudied and unstudied research objectives. We find that the majority of VGI studies to date focus on technical aspects of VGI, notably on the potential of V2G systems to facilitate load balancing or to minimize electricity costs, in some cases including environmental goals as constraints. Only a few studies directly investigate the role of consumer acceptance and driver behavior within such systems, and barely any studies address the need for institutional capacity and cross-sectoral policy coordination. These gaps create promising opportunities for future research. [ABSTRACT FROM AUTHOR]

Abstract: Wind is strong and steady over the ocean, but on-site marine meteorological data are sparse for evaluation of oceanic wind power. Here, we draw on meteorological station, satellite data (QuikSCAT), and both theoretical and practical measures of wind turbine performance. The meteorological stations measure directly at high time resolution but low spacial resolution, and provide validation and adjustment of the satellite data. The satellite data provide near-complete spacial coverage at lower time resolution. For the southern coast of Brazil, we use both data sets to evaluate the location, seasonal timing, and availability of the wind power resource. Then, using bathymetry and the properties of current wind-electric technology, we develop maps of wind speed, wind power density, and practical turbine output in power units (MW). In the shallower waters of south Brazil, the most favorable conditions are along the coast between 28°S and 33°S. In just this one coastal area, we find a total resource of 102GW average electrical production, approximately equal to the electric demand of the entire country. [Copyright &y& Elsevier]

Abstract: Vehicle-to-grid power (V2G) uses electric-drive vehicles (battery, fuel cell, or hybrid) to provide power for specific electric markets. This article examines the systems and processes needed to tap energy in vehicles and implement V2G. It quantitatively compares today''s light vehicle fleet with the electric power system. The vehicle fleet has 20 times the power capacity, less than one-tenth the utilization, and one-tenth the capital cost per prime mover kW. Conversely, utility generators have 10–50 times longer operating life and lower operating costs per kWh. To tap V2G is to synergistically use these complementary strengths and to reconcile the complementary needs of the driver and grid manager. This article suggests strategies and business models for doing so, and the steps necessary for the implementation of V2G. After the initial high-value, V2G markets saturate and production costs drop, V2G can provide storage for renewable energy generation. Our calculations suggest that V2G could stabilize large-scale (one-half of US electricity) wind power with 3% of the fleet dedicated to regulation for wind, plus 8–38% of the fleet providing operating reserves or storage for wind. Jurisdictions more likely to take the lead in adopting V2G are identified. [Copyright &y& Elsevier]

The goal of this research is to understand the economics of anticipated large-scale changes in the electric system. 86 million different combinations of renewable generation (wind and solar), natural gas, and three storage types (hydrogen storage, electric vehicles equipped with vehicle-to-grid (V2G) technology, and building heat) are modeled within the PJM Interconnection. The corresponding electric systems are then operated and constrained to meet the load every hour over four years. The total cost of each energy system is calculated, both with and without externalities, to find the least cost energy systems. Using today’s costs of conventional and renewable electricity and without adding any externalities, the cost-minimum system includes no renewable generation, but does include EVs. When externalities are included, however, the most cost-effective to system covers 50% of the electric load with renewable energy and runs reliably without need for either new conventional generation or purpose-built storage. The three novel energy policy implications of this research are: (1) using today’s cost of renewable electricity and estimates of externalities, it is cost effective to implement 240 GW of renewable electricity to meet 50% of the total electric load; (2) there is limited need to construct new natural gas power plants, especially from a system-wide perspective; and (3) existing coal plants may still be useful to the energy system, and instead of being retired, should be repurposed to occasionally provide generation. [ABSTRACT FROM AUTHOR]

Abstract: This paper describes a method for assessing the electric production and value of wind resources, specifically for the offshore environment. Three steps constitute our method. First, we map the available area, delimiting bathymetric areas based on turbine tower technology, then assess competing uses of the ocean to establish exclusion zones. From exclusion zones, bathymetry, and turbine tower water depth limitations, the water sheet area available for wind turbines is calculated. The second step is calculation of power production starting from available area, which determines the location and count of turbines. Then existing wind data are extrapolated to turbine height and, along with the turbine power output curve, they are used to establish the expected electric power production on an hourly basis. The third step calculates market value based on the hourly electric market at the nearest electric grid node. To illustrate these methods, we assess the offshore wind resource of the US state of Delaware. We find year-round average output of over 5200MW, or about four times the average electrical consumption of the state. On local wholesale electricity markets, this would produce just over $2 billion/year in revenue. Because the methods described here do not rely on constructing meteorological towers nor on proprietary software, they are more accessible to a local government, state college, or other organization. For example, these methods can be carried out as an initial assessment of resources, or by a government or public entity as a check on claims by private applicants. [Copyright &y& Elsevier]