Combined economic and emission dispatch considering conventional and wind power generating units

Combined economic and emission dispatch (CEED) is an optimization solution to the short-term demand and supply balancing in the power network. Given that wind power is playing an increasing role in the UK, this paper develops a CEED model for a combined conventional and wind power system under the UK energy policies. The proposed model aims to determine the optimal operation strategy for the given system with the consideration of wind power curtailment and reservation and also the environmental aspect, especially the carbon price of greenhouse gases (GHG) and emission limits of decarbonisation scenarios. From two case studies, increasing the carbon price at a low emission limit leads to an increase in the total cost, but the rate of the increase is mitigated on decreasing the emission limits. Moreover, dispatch is dominated by the carbon price at high emission allowance levels and by the emission allowance at low emission allowances

Energy storage in the UK electrical network : estimation of the scale and review of technology options

This paper aims to clarify the difference between stores of energy in the form of non-rechargeable stores of energy such as fossil-fuels, and the storage of electricity by devices that are rechargeable. The existing scale of these two distinct types of storage is considered in the UK context, followed by a review of rechargeable technology options. The storage is found to be overwhelmingly contained within the fossil-fuel stores of conventional generators, but their scale is thought to be determined by the risks associated with long supply chains and price variability. The paper also aims to add to the debate regarding the need to have more flexible supply and demand available within the UK electrical network in order to balance the expected increase of wind derived generation. We conclude that the decarbonisation challenge facing the UK electricity sector should be seen not only as a supply and demand challenge but also as a storage challenge. (c) 2010 Elsevier Ltd. All rights reserved

An Integrated Market for Electricity and Natural Gas Systems with Stochastic Power Producers

In energy systems with high shares of weather-driven renewable power sources, gas-fired power plants can serve as a back-up technology to ensure security of supply and provide short-term flexibility. Therefore, a tighter coordination between electricity and natural gas networks is foreseen. In this work, we examine different levels of coordination in terms of system integration and time coupling of trading floors. We propose an integrated operational model for electricity and natural gas systems under uncertain power supply by applying two-stage stochastic programming. This formulation co-optimizes day-ahead and real-time dispatch of both energy systems and aims at minimizing the total expected cost. Additionally, two deterministic models, one of an integrated energy system and one that treats the two systems independently, are presented. We utilize a formulation that considers the linepack of the natural gas system, while it results in a tractable mixed-integer linear programming (MILP) model. Our analysis demonstrates the effectiveness of the proposed model in accommodating high shares of renewables and the importance of proper natural gas system modeling in short-term operations to reveal valuable flexibility of the natural gas system. Moreover, we identify the coordination parameters between the two markets and show their impact on the system's operation and dispatch

Integrating electricity markets: Impacts of increasing trade on prices and emissions in the western United States

This paper presents empirically-estimated average hourly relationships between regional electricity trade in the United States and prices, emissions, and generation from 2015 through 2018. Consistent with economic theory, the analysis finds a negative relationship between electricity prices in California and regional trade, conditional on local demand. Each 1 gigawatt-hour increase in California electricity imports is associated with an average $0.15 per megawatt-hour decrease in the California Independent System Operator's wholesale electricity price. There is a net-negative short term relationship between carbon dioxide emissions in California and electricity imports that is partially offset by positive emissions from exporting neighbors. Specifically, each 1 GWh increase in regional trade is associated with a net 70-ton average decrease in CO2 emissions across the western U.S., conditional on demand levels. The results provide evidence that electricity imports mostly displace natural gas generation on the margin in the California electricity market. A small positive relationship is observed between short-run SO2 and NOx emissions in neighboring regions and California electricity imports. The magnitude of the SO2 and NOx results suggest an average increase of 0.1 MWh from neighboring coal plants is associated with a 1 MWh increase in imports to California

Mainstreaming New Renewable Energy Technologies

This paper outlines the benefits, obstacles and options for governments to support international markets for technology development. International markets for new energy technologies offer greater scope, thereby increasing the incentives and opportunities for technology improvements. As the market is supported by more independent governments, the confidence of technology developers and producers that future markets for their products will exist is increasing, thus enabling capital access and inducing R&D investment and exploration of improved production processes. The bigger markets also allow for international competition, thus allowing for the application of the best available technology. The government challenge to induce sufficient RD&D remains and with international markets the benefits and costs of national governments free-riding on international effort needs to be addressed. Finally, we discuss how international co-operation can be used to evolve the energy system in such a way that it can integrate new technologies at minimum cost

An Assessment of PIER Electric Grid Research 2003-2014 White Paper

This white paper describes the circumstances in California around the turn of the 21st century that led the California Energy Commission (CEC) to direct additional Public Interest Energy Research funds to address critical electric grid issues, especially those arising from integrating high penetrations of variable renewable generation with the electric grid. It contains an assessment of the beneficial science and technology advances of the resultant portfolio of electric grid research projects administered under the direction of the CEC by a competitively selected contractor, the University of California’s California Institute for Energy and the Environment, from 2003-2014

Regulatory Challenges to European Electricity Liberalisation

Regulatory Challenges to European Electricity Liberalisatio

A review on the complementarity of renewable energy sources: concept, metrics, application and future research directions

It is expected, and regionally observed, that energy demand will soon be covered by a widespread deployment of renewable energy sources. However, the weather and climate driven energy sources are characterized by a significant spatial and temporal variability. One of the commonly mentioned solutions to overcome the mismatch between demand and supply provided by renewable generation is a hybridization of two or more energy sources in a single power station (like wind-solar, solar-hydro or solar-wind-hydro). The operation of hybrid energy sources is based on the complementary nature of renewable sources. Considering the growing importance of such systems and increasing number of research activities in this area this paper presents a comprehensive review of studies which investigated, analyzed, quantified and utilized the effect of temporal, spatial and spatio-temporal complementarity between renewable energy sources. The review starts with a brief overview of available research papers, formulates detailed definition of major concepts, summarizes current research directions and ends with prospective future research activities. The review provides a chronological and spatial information with regard to the studies on the complementarity concept.Comment: 34 pages 7 figures 3 table

Take-or-Pay Contracts for Renewables Deployment

Renewables require support policies to deliver the European 20% target. We discuss the requirements for least cost development and efficient operation and quantify how different schemes (i) allow for the development of a renewable energy technology portfolio; (ii) reduce rent transfers to infra-marginal technologies or better than marginal resource bases; and (iii) minimise regulatory risk and thus capital costs for new projects. Long-term take or pay contracts minimise regulatory uncertainty, create appropriate incentives for location and operation, allow for efficient system operation and seem compatible with European state aid. We discuss how property rights legislation protects existing renewables investors, and thus can ensure ongoing investment during a transition towards the new scheme