Quantification of Energy Flexibility and Survivability of All-Electric Buildings with Cost-Effective Battery Size: Methodology and Indexes

Abstract

All-electric buildings are playing an important role in the electrification plan towards energy-neutral smart cities. Batteries are key components in all-electric buildings that can help the demand-side energy management as a flexibility asset and improve the building survivability in the case of power outages as an active survivability asset. This paper introduces a novel methodology and indexes for determining cost-effective battery sizes. It also explores the possible trade-off between energy flexibility and the survivability of all-electric buildings. The introduced methodology uses IDA-ICE 4.8 as a building performance simulation tool and MATLAB® 2017 as a post-processing calculation tool for quantifying building energy flexibility and survivability indexes. The proposed methodology is applied to a case study of a Norwegian single-family house, where 10 competitive designs, 16 uncertainty scenarios, and 3 dynamic pricing tariffs suggested by the Norwegian regulators are investigated. The methodology provides informative support for different stakeholders to compare various building designs and dynamic pricing tariffs from the flexibility and survivability points of view. Overall, the results indicate that larger cost-effective batteries usually have higher active survivability and lower energy flexibility from cost- effectiveness perspective. For instance, when the time of use tariff is applied, the cost-effective battery size varies between 40 and 65 kWh (daily storage). This is associated with a cost-effective flexibility index of 0.4–0.55%/kWh and an active survivability index of 63–80%.

Techno-Economic Analysis of the Energy Resilience Performance of Energy-Efficient Buildings in a Cold Climate and Participation in the Flexibility Market

“…Homaei and Hamdy define the lower threshold of the habitability range in the Norwegian environment as 15 • C in their work on the quantification of energy flexibility and survivability with batteries. The habitability defined in their work is analogous to survivability in this study [5]. Similarly, Kesik et al define the lower temperature threshold for passive habitability as 15 • C in mechanically cooled buildings.…”

“…The research includes power outage simulation and analyzing the results of building design in a multifamily building [4]. Hamdy et al introduced the cost-effective flexibility index (CEFI) and active survivability index (ASI) as comparison indicators of building design to analyze survivability from an economic viewpoint in fully electrified buildings in the cold climate of Norway [5]. Homaei and Hamdy experimented with the quantification of thermal resilience in buildings for prolonged power outages and formulated a standard framework for the cold climate.…”

Retrofitting Buildings into Thermal Batteries for Demand-Side Flexibility and Thermal Safety during Power Outages in Winter

“…Moreover, the demonstration phase in Section 4.3 points out that the flats located on the lower floor (and having hence a larger exposed surface, since the building is on pilotis) have generally lower temperatures with respect to the ones located on the upper floors, and this also affects the possibility of remaining in comfortable conditions after an energy interruption. However, the study allows one to verify that all the apartments of the retrofitted buildings are able to maintain habitable indoor conditions under extreme events, such as a power outage [57], for at least 5 days [41,44].…”

“…Homaei and Hamdy [41] explored, through energy simulations, the winter passive survivability of a representative Norwegian single-family house during the coldest week using a typical weather file (IWEC) suggesting ten different building designs by changing the design parameters. Wilson [42] discussed, in his study on thermal habitability of buildings during power outages, the analysis published by the Urban Green Council [43] on six different residential building types during week-long power outages under typical summer and winter conditions.…”

Energy Flexibility and towards Resilience in New and Old Residential Houses in Cold Climates: A Techno-Economic Analysis

“…Research has been focused on 'habitability' as part of energy-resilient buildings [24] either for mild climates [25] or for overheating conditions under grid loss [21,22]. The concept of 'habitability' focuses on the indoor thermal conditions and comfort and it refers to the length the building can remain in habitable thermal conditions after power loss through a reduction in heat transfer, natural ventilation and natural light [26].…”