Sizing and optimizing the operation of thermal energy storage units in combined heat and power plants: An integrated modeling approach

Benalcazar, Pablo

doi:10.1016/j.enconman.2021.114255

Cited by 34 publications

(11 citation statements)

References 33 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The energy balance of the system, taking into account the storage efficiency and the charging and discharging efficiencies, is expressed in Equation (30). The binary variable z(t) is used to illustrate the TES charging and discharging operation status, see Equation (31). Equations ( 32) and (33) express the constraints that the stored thermal energy must be lower than the maximum storage capacity of the system, which depends on TES volume and DH supply and return temperatures.…”

Section: Minimum Uptime and Downtimementioning

confidence: 99%

“…However, the annual profile with 8760 time steps makes is difficult to solve due to complexity of optimization model [31][32][33]. To limit the computational time without significantly impacting the simulation results [32], the approach of typical periods is used in this work [33], a full year period was discretized into 12 typical days, each of them being representative for a month.…”

Section: Input Datamentioning

confidence: 99%

See 1 more Smart Citation

Multi-Objective Optimal Integration of Solar Heating and Heat Storage into Existing Fossil Fuel-Based Heat and Power Production Systems

Wang

Blondeau

2022

Energies

View full text Add to dashboard Cite

Increasing the share of Renewable energy sources in District Heating (DH) systems is of great importance to mitigate their CO2 emissions. The combined integration of Solar Thermal Collectors (STC) and Thermal Energy Storage (TES) into existing Combined Heat and Power (CHP) systems can be a very cost-effective way to do so. This paper aims at finding the optimal design of STC and TES systems integrated in existing CHP’s considering two distinct objectives: economic profitability and environmental impact. To do so, we developed a three-stage framework based on Pareto-optimal solutions generated by multi-objective optimization, a Technique for Order Preference by Similarity to Ideal Solution (TOPSIS)-entropy method to select the optimal solution, followed by the definition of final Operation strategy. We proposed relevant improvement of the state-of-the-art models used in similar analysis. We also applied the proposed methodology to the case of a representative, 12 MWth CHP plant. Our results show that, while the addition of TES or STC alone results in limited performances and/or higher costs, both the cost and the CO2 emissions can be reduced by integrating the optimal combination of STC and TES. For the selected, optimal solution, carbon emissions are reduced by 10%, while the Annual Total Cost (ATC) is reduced by 3%. It also improves the operational flexibility and the efficiency by peak load shaving, load valley filling and thus by decreasing the peak load boiler operation. Compared to the addition of STC alone, the use of TES results in an increased efficiency, from 88% to 92%. The optimal share of STC is then increased from 7% to 10%.

show abstract

Section: Minimum Uptime and Downtimementioning

confidence: 99%

Section: Input Datamentioning

confidence: 99%

Multi-Objective Optimal Integration of Solar Heating and Heat Storage into Existing Fossil Fuel-Based Heat and Power Production Systems

Wang

Blondeau

2022

Energies

View full text Add to dashboard Cite

show abstract

“…As described in Section 1, this work expands the scope of our previous study [20] by (a) modeling and incorporating energy and electricity prices uncertainties and (b) investigating the economic and operational impacts of future energy and carbon prices on the operation of a coal-fired CHP system with thermal energy storage. Furthermore, the model used in the present study is an adapted version of the mixed-integer linear programming approach described in [21,22]. In our previous work, the feasible operating region of the combined heat and power plant equipped with an extraction-condensing steam turbine was modeled as a combination of convex points that represented the hourly thermal and electrical power generation.…”

Section: Energy System Modelmentioning

confidence: 99%

Assessing the Effects of Uncertain Energy and Carbon Prices on the Operational Patterns and Economic Results of CHP Systems

2021

Self Cite

View full text Add to dashboard Cite

In the power and heat sectors, the uncertainty of energy and carbon prices plays a decisive role in the rationale for decommissioning/repurposing coal-fired CHP (combined heat and power) systems and on investment decisions of energy storage units. Therefore, there is a growing need for advanced methods that incorporate the stochastic disturbances of energy and carbon emission prices into the optimization process of an energy system. In this context, this paper proposes an integrated method for investigating the effects of uncertain energy and carbon prices on the operational patterns and financial results of CHP systems with thermal energy storage units. The approach combines mathematical programming and Monte Carlo simulation. The computational process generates feasible solutions for profit maximization considering the technical constraints of the CHP system and the variation of energy and carbon emission prices. Four scenarios are established to compare the operational patterns and economic performance of a CHP system in 2020 and 2030. Results show that in 2020, there is an 80% probability that the system’s annual profit will be less than or equal to €30.98 M. However, at the same probability level, the annual profit in 2030 could fall below €11.88 M. Furthermore, the scenarios indicate that the incorporation of a thermal energy storage unit leads to higher expected profits (€0.74 M in 2020 and €0.71 M in 2030). This research shows that coal-fired CHP plant operators will face costly risks and potentially greater challenges in the upcoming years with the increasing regulatory and financial pressure on CO2 emissions and the EU’s plan of phasing out fossil fuels from electricity and heat generation.

show abstract

“…Previous works have investigated strategies to increase the flexibility of CHP plants (mainly coal and natural gas-fired plants) and evaluated the profitability of flexibility measures on a plant level. Table 1 provides an overview of main outcomes from studies that investigate plant-level flexibility measures, including turbine bypasses [28][29][30], a variable power-to-heat ratio [28,30,31], thermal energy storage (TES) [28,29,[32][33][34][35], coordination with electric boilers [29,32,33,36], steam extraction regulation [37,38], steam storage systems [39,40], thermal buffers [41], disconnection of the low-pressure turbine section [29,32,42], and control systems for improved operational flexibility (e. g., cycling and ramp rates) [43][44][45]. The cited studies demonstrate that there are several ways to enhance the technical potential for CHP plant flexibility, that might increase the plant revenue.…”

Section: Introductionmentioning

confidence: 99%

Flexibility provision by combined heat and power plants – An evaluation of benefits from a plant and system perspective

Beiron

Göransson

Normann

et al. 2022

Energy Conversion and Management: X

View full text Add to dashboard Cite

Sizing and optimizing the operation of thermal energy storage units in combined heat and power plants: An integrated modeling approach

Cited by 34 publications

References 33 publications

Multi-Objective Optimal Integration of Solar Heating and Heat Storage into Existing Fossil Fuel-Based Heat and Power Production Systems

Multi-Objective Optimal Integration of Solar Heating and Heat Storage into Existing Fossil Fuel-Based Heat and Power Production Systems

Assessing the Effects of Uncertain Energy and Carbon Prices on the Operational Patterns and Economic Results of CHP Systems

Flexibility provision by combined heat and power plants – An evaluation of benefits from a plant and system perspective

Contact Info

Product

Resources

About