ASEAN grid flexibility: Preparedness for grid integration of renewable energy

In 2015, ASEAN established a goal of increasing its renewable energy share in its energy portfolio from approximately 13–23% by 2025. Renewable electricity, especially intermittent and variable sources, presents challenges for grid operators due to the uncertain timing and quantity of electricity supply. Grid flexibility, the electric grid's ability to respond to changing demands and supply, now stands a key resource in responding to these uncertainties while maximizing the cost-effective role of clean energy. We develop and apply a grid flexibility assessment tool to assess ASEAN's current grid flexibility using six quantitative indicators: grid reliability, electricity market access; load profile ramp capacity; quality of forecasting tools; proportion of electricity generation from natural gas; and renewable energy diversity. We find that ASEAN nations cluster into three groups: better; moderately; and the least prepared nations. We develop an analytical ramp rate calculator to quantify expected load ramps for ASEAN in an integrated ASEAN Power Grid scenario. The lack of forecasting systems and limited electricity market access represent key weaknesses and areas where dramatic improvements can become cost-effective means to increase regional grid flexibility. As ASEAN pursues renewable energy targets, regional cooperation remains essential to address identified challenges. Member nations need to increase grid flexibility capacity to adequately prepare for higher penetrations of renewable electricity and lower overall system costs

Distributed Stochastic Market Clearing with High-Penetration Wind Power

Integrating renewable energy into the modern power grid requires risk-cognizant dispatch of resources to account for the stochastic availability of renewables. Toward this goal, day-ahead stochastic market clearing with high-penetration wind energy is pursued in this paper based on the DC optimal power flow (OPF). The objective is to minimize the social cost which consists of conventional generation costs, end-user disutility, as well as a risk measure of the system re-dispatching cost. Capitalizing on the conditional value-at-risk (CVaR), the novel model is able to mitigate the potentially high risk of the recourse actions to compensate wind forecast errors. The resulting convex optimization task is tackled via a distribution-free sample average based approximation to bypass the prohibitively complex high-dimensional integration. Furthermore, to cope with possibly large-scale dispatchable loads, a fast distributed solver is developed with guaranteed convergence using the alternating direction method of multipliers (ADMM). Numerical results tested on a modified benchmark system are reported to corroborate the merits of the novel framework and proposed approaches.Comment: To appear in IEEE Transactions on Power Systems; 12 pages and 9 figure

Market design

Europe is liberalising electricity in accordance with the European Commission’s Electricity Directives. Different countries have responded differently, notably in the extent of restructuring, treatment of mergers, market power, and vertical unbundling. While Britain and Norway have achieved effective competition, others like Germany, Spain and France are still struggling to deal with dominant and sometimes vertically integrated companies. The Netherlands offers an interesting intermediate case, where good economic analysis has sometimes been thwarted by legalistic interpretations. Investment under the new Emissions Trading system could further transform the electricity industry but may be hampered by slow progress in liberalising European gas markets

Local flexibility market design for aggregators providing multiple flexibility services at distribution network level

This paper presents a general description of local flexibility markets as a market-based management mechanism for aggregators. The high penetration of distributed energy resources introduces new flexibility services like prosumer or community self-balancing, congestion management and time-of-use optimization. This work is focused on the flexibility framework to enable multiple participants to compete for selling or buying flexibility. In this framework, the aggregator acts as a local market operator and supervises flexibility transactions of the local energy community. Local market participation is voluntary. Potential flexibility stakeholders are the distribution system operator, the balance responsible party and end-users themselves. Flexibility is sold by means of loads, generators, storage units and electric vehicles. Finally, this paper presents needed interactions between all local market stakeholders, the corresponding inputs and outputs of local market operation algorithms from participants and a case study to highlight the application of the local flexibility market in three scenarios. The local market framework could postpone grid upgrades, reduce energy costs and increase distribution grids’ hosting capacity.Postprint (published version

A Community Microgrid Architecture with an Internal Local Market

This work fits in the context of community microgrids, where members of a community can exchange energy and services among themselves, without going through the usual channels of the public electricity grid. We introduce and analyze a framework to operate a community microgrid, and to share the resulting revenues and costs among its members. A market-oriented pricing of energy exchanges within the community is obtained by implementing an internal local market based on the marginal pricing scheme. The market aims at maximizing the social welfare of the community, thanks to the more efficient allocation of resources, the reduction of the peak power to be paid, and the increased amount of reserve, achieved at an aggregate level. A community microgrid operator, acting as a benevolent planner, redistributes revenues and costs among the members, in such a way that the solution achieved by each member within the community is not worse than the solution it would achieve by acting individually. In this way, each member is incentivized to participate in the community on a voluntary basis. The overall framework is formulated in the form of a bilevel model, where the lower level problem clears the market, while the upper level problem plays the role of the community microgrid operator. Numerical results obtained on a real test case implemented in Belgium show around 54% cost savings on a yearly scale for the community, as compared to the case when its members act individually.Comment: 16 pages, 15 figure

Relying on storage or ICT? How to maintain low voltage grids' stability with an increasing feed-in of fluctuating renewable energy sources

Since the beginning of the new century our electricity system is changing rapidly. Distributed energy resources, such as wind or solar energies are becoming more and more important. These energies are producing fluctuating electricity, which is fed into low voltage distribution grids. The resulting volatility complicates the exact balancing of demand and supply. These changes can lead to distribution grid instabilities, damages of electronic devices or even power outages and might therefore end in deadweight losses affecting all electricity users. A concept to tackle this challenge is matching demand with supply in real-time, which is known as smart grids. In this study, we focus on two smart grids' key components: decentralized electricity storages and smart meters. The aim of this study is to provide new insights concerning the low diffusion of smart meters and decentralized electricity storages and to examine whether we are facing situations of positive externalities. During our study we conducted eight in-depth expert interviews. Our findings show that the diffusion of smart meters as well as decentralized electricity storages is widely seen as beneficial to society. This study identifies the most important stakeholders and various related private costs and benefits. As private benefits are numerous but widely distributed among distinct players, we argue that we face situations of positive externalities and thus societal desirable actions are omitted. We identify and discuss measures to foster diffusion of the two studied smart grid key components. Surprisingly, we find that direct interventions like subsidies are mostly not seen as appropriate even by experts from industries that would directly benefit from them. As the most important point, we identified well-designed and clearly defined regulatory and legal frameworks that are free of contradictions. --smart meter,decentralized electricity storage,smart grid,externality

Diverse, remote and innovative - Prospects for a globally unique electricity network and market in Western Australia

WA’s electricity industry supply infrastructure comprises the South West Inter-connected System (SWIS), the North West Interconnected System (NWIS) and 29 regional non-interconnected power systems 1. WA exhibits a diversity of generation systems located in some of the most isolated regions of Australia, supplying a wide range of energy demand profiles. These characteristics and the unique networks that comprises WA’s electricity infrastructure makes WA a unique place to research, develop and integrate new technical options within a world-class industrialised electricity system

Diverse, remote and innovative - Prospects for a globally unique electricity network and market in Western Australia

WA’s electricity industry supply infrastructure comprises the South West Inter-connected System (SWIS), the North West Interconnected System (NWIS) and 29 regional noninterconnected power systems 1. WA exhibits a diversity of generation systems located in some of the most isolated regions of Australia, supplying a wide range of energy demand profiles. These characteristics and the unique networks that comprises WA’s electricity infrastructure makes WA a unique place to research, develop and integrate new technical options within a world-class industrialised electricity system