An integrated framework for operational flexibility assessment in multi-period power system planning with renewable energy production

Abstract

To cite this version:Islam Abdin, Enrico Zio. An integrated framework for operational flexibility assessment in multiperiod power system planning with renewable energy production. Applied Energy, Elsevier, 2018, 222, pp.• Quantitative modeling framework for operational flexibility assessment.• Integration of short-term constraints in generation expansion planning model. • Renewable energy penetration drives flexibility needs higher than carbon limits. A B S T R A C TThis paper proposes an integrated framework for operational flexibility assessment in power system planning with a significant share of intermittent renewable energy sources (RES). The framework proposed includes: (i) the formulation of an integrated generation expansion planning (GEP) and unit commitment (UC) model accounting for key short-term technical constraints, (ii) the elaboration of accurate and systematic horizon reduction methods to alleviate the computational burden of the resulting large-sized optimization problems and (iii) the definition of suitable metrics for the operational flexibility assessment of the obtained plans. The framework is applied to a ten year planning horizon of a realistically sized case study representing the national power system of France, under several scenarios of RES penetration levels and carbon limits, spanning levels of up to 50%. The importance of incorporating the detailed short-term constraints within long-term planning models is shown. The results of the assessment show that, under high renewable energy penetration, neglecting the short-term constraints may lead to plans significantly short on flexibility, reaching shortage levels of up to 50% in frequency and several GWs in magnitude. Also, the load not served reaches levels of up to 3% and carbon emission is underestimated by up to 60%. Furthermore, the results highlight the importance of relying on suitable quantitative metrics for operational flexibility assessment in power systems planning rather than solely relying on generic performance measures, such as system costs and mixes of power plants, which are shown not to sufficiently reflect the flexibility levels of the obtained plans.improvements in the details considered (e.g. reliability and maintenance), policy developments, such as the restructuring of the power sector, renewable energy sources (RES) integration and support schemes, uncertainty and stochasticity modeling, and the consideration of real-options for adaptive power systems design [3].One of the most recent concerns in power systems planning is dealing with the high share of intermittent RES penetration required in the system, driven by strict environmental policies, such as the EU renewable energy directive [4] and its proposed revision [5], and other regional and national targets. The resulting increased variability in the net load (system demand minus RES production) requires that the

Multi-Period Generation Expansion Planning for Sustainable Power Systems to Maximize the Utilization of Renewable Energy Sources

“…In addition, the operation constraints to model these requirements (such as ramping constraints and minimum up/down time limits) are usually neglected or simplified in the conventional GEP models. To address this challenge, several studies have been carried out to consider the chronological sequence of RES and then incorporate the detailed operation constraints in GEP models [25][26][27][28][29][30][31]. Their findings reveal that neglecting or simplifying the detailed operation constraints may have great impacts on the results of GEP models.…”

“…Their findings reveal that neglecting or simplifying the detailed operation constraints may have great impacts on the results of GEP models. Specifically, experimental results in [28,29] showed that the GEP model without these operation constraints may underestimate carbon emissions, RES curtailments, and even the values of load not served. Numerical results in [30] showed that flexible generation capacity and wind curtailment are both underestimated in GEP models without considering the detailed operation constraints.…”

Pan-European Analysis on Power System Flexibility

“…Some work focuses on qualitative analysis or theoretical developments [4]. Setting up a quantitative flexibility evaluation method is essential to identify flexibility needs and sources; however, there is no consensus on which metrics are best suited [5], and how the indicators relate with RES curtailment or loss of load. Moreover, there is the need to find a compromise between computational complexity and meaningfulness of the indicators [6].…”

“…The focus is in the evolution of the European power system from 2020 to 2025, where the new legislative proposal will enter into force. There are several previous works on specific countries, as Germany [11], France [5] and Greece [12], but less on assessing the European system as a whole [13]. Although there are several previous works focusing on the analysis of 1-h ramps, we consider essential to extend this analysis up to 3 or 4 hour ramps, at least in countries with significant solar photovoltaic (PV) installed capacity, as these longer-lasting ramps impact the operation of the grid and the sizing of the operational reserve needs.…”

Pan-European Analysis on Power System Flexibility

“…Some work focuses on qualitative analysis or theoretical developments [4]. Setting up a quantitative flexibility evaluation method is essential to identify flexibility needs and sources; however, there is no consensus on which metrics are best suited [5], and how the indicators relate with RES curtailment or of the requirements of the system. Ramp events should be characterized in terms of ramping start and end time, ramping duration, ramping rate, and ramping magnitude [9].…”