Methods for evaluating the impact of renewable resource variability on grid operation and planning

With the recent interest in increasing the penetration of renewable energy sources onto the power grid, there has been an unprecedented rapid deployment of wind generation, especially in the US Pacific Northwest. While wind farm developers have continued to expand their operations, power system operators are left to deal with the consequences – specifically, the uncontrollable, variable nature of the wind. While this variability can be quantified using traditional statistical measures, these statistics are often not directly usable by system operators. Composed of two papers, this research explores other methods for evaluating the variability of renewable resources to better understand their impact on the grid. The first paper examines how renewable penetration can be increased by diversifying the types of resources used (e.g., integrating an equal mix of wind, solar, and ocean wave power). The second paper builds off of the first by developing a solution to the lack of available power generation data necessary to conduct this research and then by using generated synthetic data to examine the impacts of increasing renewable resource penetration levels. Both papers point to the value of a diversified renewable energy portfolio, including high-levels of wind, solar, and ocean wave power generation

Development of a grid-scale energy storage solution via demand response using model predictive control of multiple residential water heaters

As the growth of renewable energy sources, such as wind, solar, and ocean wave, increases, their impact on the electrical grid has been rapidly escalating. Although renewable resources have been able to offset some traditional generation, they have also brought a need for increasing reserve capacity due to their non-dispatchable, variable nature. While there are a variety of possible solutions to this issue including reduced dispatch windows and more accurate forecasting, one proposed solution is the use of grid-scale energy storage. Unfortunately, most grid-scale storage solutions are either too expensive or suffer from geographical limitations. One alternative, however, is the implementation of demand response: the use of many distributed energy storage resources, such as the millions of residentially-installed electric water heaters in the Pacific Northwest. This research presents the development of a control methodology to combine multiple residential water heaters into a larger grid-scale storage resource while still satisfying the needs of consumers. Results demonstrate the ability of this control scheme, model predictive control, to make decisions based on predicted inputs to provide a balancing service for renewable energy resources, furthering the goal of increasing their penetration onto the grid

A new frontier approach to model the eco-efficiency in European countries

This study aims to evaluate the resource and environment efficiency problem of European countries. We specify a new stochastic frontier model where Gross Domestic Product (GDP) is considered as the desirable output and Greenhouse Gases (GHG) emissions as the undesirable output. Capital, Labour, Fossil fuels and Renewable Energy consumption are regarded as inputs. GDP/GHG ratio is maximized given the values of the other four variables. The study is divided into two distinct periods: 2000-2004 and 2005-2011. This division is related to the implementation of the Kyoto Protocol in 2005, and will allow us to evaluate the difference between the levels of efficiency before and after the establishment of environmental targets. Since stochastic frontier models are typically ill-posed, a new maximum entropy approach to assess technical efficiency, which combines information from the data envelopment analysis and the structure of composed error from the stochastic frontier approach without requiring distributional assumptions, is presented in this work

Improving Wind Farm Dispatchability Using Model Predictive Control for Optimal Operation of Grid-Scale Energy Storage

This paper demonstrates the use of model-based predictive control for energy storage systems to improve the dispatchability of wind power plants. Large-scale wind penetration increases the variability of power flow on the grid, thus increasing reserve requirements. Large energy storage systems collocated with wind farms can improve dispatchability of the wind plant by storing energy during generation over-the-schedule and sourcing energy during generation under-the-schedule, essentially providing on-site reserves. Model predictive control (MPC) provides a natural framework for this application. By utilizing an accurate energy storage system model, control actions can be planned in the context of system power and state-of-charge limitations. MPC also enables the inclusion of predicted wind farm performance over a near-term horizon that allows control actions to be planned in anticipation of fast changes, such as wind ramps. This paper demonstrates that model-based predictive control can improve system performance compared with a standard non-predictive, non-model-based control approach. It is also demonstrated that secondary objectives, such as reducing the rate of change of the wind plant output (i.e., ramps), can be considered and successfully implemented within the MPC framework. Specifically, it is shown that scheduling error can be reduced by 81%, reserve requirements can be improved by up to 37%, and the number of ramp events can be reduced by 74%.This is the publisher’s final pdf. The published article is copyrighted by the author(s) and published by MDPI. The published article can be found at: http://www.mdpi.com/journal/energies.Keywords: reserve generation, energy storage, wind generation, model predictive control (MPC), wind ramp

Ways of increasing the efficiency of tax collection to the budgets of local communities on the basis of tax management

The processes of fiscal decentralization have provided new opportunities for local self-governments: independent formation of local budgets; direct intergovernmental relations; expansion of the tax base, etc. The steps taken in the field of decentralization are currently not systemic. The distribution of fiscal payments between different levels of the budget system is the purpose of the tax system development, which would allow to provide quality social services to the population and influence the economic development of the territory. The main directions of tax system development on the basis of tax management are substantiated as following: strengthening the role of local taxes; establishing the effective interaction of local governments with economic entities operating in the territory to increase budget revenues; ensuring the fair distribution of the tax burden and its reduction while seeking budgetary compensators; strengthening the tax control; ensuring the efficient informational and explanatory work and interaction of local self-government bodies and taxpayers. The author's vision of the tax system within the new architecture of the administrative-territorial system is offered. The inclusion of personal income tax in local taxes and change in the mechanism of crediting the tax to local budgets are substantiated. There are two alternatives to change the procedure for crediting personal income tax to local budgets, due to which the associated burden will be distributed among all participants: 1) crediting personal income tax to local budgets at the place of residence of the individual payer; 2) giving the individual payer the right to choose which budget should include the amount of tax paid (by place of work or place of residence). The directions of increasing the property taxes accumulated in local budgets are defined. The paper develops a model of the form of self-taxation of the population in territorial communities. According to the model, the residents are involved in the accumulation and distribution of tax resources. The suggested model is based on the accumulation of financial resources by a parity principle: the amount of financial contribution of local governments is determined at a level not lower than the amount contributed by residents.</jats:p