Browsing by Author "Bishop D"

Now showing 1 - 3 of 3
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    Cooling demand reduction with nighttime natural ventilation to cool internal thermal mass under harmonic design-day weather conditions
    (Elsevier Ltd, 2025-02-01) Li M; Shen X; Wu W; Cetin K; Mcintyre F; Wang L; Ding L; Bishop D; Bellamy L; Liu M
    Cooling demand is steadily increasing across different climate zones due to global warming. A potential solution for cooling demand reduction is applying nighttime natural ventilation to cool internal thermal mass. However, a simplified and accurate modelling framework to assess the technique is still missing. The goal of the study is to build that framework integrated with a validated internal thermal mass model and apply the framework to quantify the cooling demand reduction potential in a space with different thermal mass and envelope configurations and in different climate zones. Results show that using Granite as internal thermal mass is three times more effective than concrete to reduce peak cooling load. Adding too much internal thermal mass can create adverse effects on cooling load reduction. The optimum thickness of internal thermal mass is between 28 and 45 mm. Envelope construction also has an influence on the performance of nighttime cooling. Applying the technique in buildings with lightweight structures reduces peak cooling load by 35.9% more than heavyweight structures. As heavyweight structures delay the release of the daily absorbed heat and cause higher indoor air temperatures at night. The two belts between the Tropic of Cancer and 60 degrees north latitude, and between the Tropic of Capricorn and 45 degrees south latitude are suitable for nighttime natural ventilation of internal thermal mass, achieving the annual cooling demand reduction above 1.25 kWh m−2. In Dessert climate zones, the technique exhibits an extraordinary potential to reduce cooling demand, up to 6.67 kWh m−2 per year.
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    The Impact of Building Level of Detail Modelling Strategies: Insights into Building and Urban Energy Modelling
    (MDPI (Basel, Switzerland), 2024-09-11) Bishop D; Mohkam M; Williams BLM; Wu W; Bellamy L; Torgal FP
    Level of detail (LoD) is an important factor in urban building energy modelling (UBEM), affecting functionality and accuracy. This work assesses the impacts of the LoD of the roof, window, and zoning on a comprehensive range of outcomes (annual heating load, peak heating demand, overheating, and time-series heating error) in a representative New Zealand house. Lower-LoD roof scenarios produce mean absolute error results ranging from 1.5% for peak heating power to 99% for overheating. Windows and shading both affect solar gains, so lower-LoD windows and/or shading elements can considerably reduce model accuracy. The LoD of internal zoning has the greatest effect on time-series accuracy, producing mean absolute heating error of up to 66 W. These results indicate that low-LoD “shoebox” models, common in UBEM, can produce significant errors which aggregate at scale. Accurate internal zoning models and accurate window size and placement have the greatest potential for error reduction, but their implementation is limited at scale due to data availability and automation barriers. Conversely, modest error reductions can be obtained via simple model improvements, such as the inclusion of eaves and window border shading. Overall, modellers should select LoD elements according to specific accuracy requirements.
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    Thermal energy storage–coupled heat pump systems: Review of configurations and modelling approaches
    (Elsevier, 2026-01-01) Zhou J; Wu W; Bellamy L; Bishop D
    Heat pump systems (HP) are effective technologies for reducing energy consumption and carbon emissions for space heating and cooling of buildings. However, with large-scale deployment, increased electrical demands can place significant stress on power networks. Integrating Thermal Energy Storage (TES) with HP systems offers a viable strategy to mitigate peak power demands and enhance overall energy efficiency by decoupling heat generation and use, hence power intensive heat-generation can be shifted to off-peak and more efficient times. Due to these benefits, the combination of HP and TES systems have gained increasing attention. A number of reviews have examined specific HP-TES configurations and applications, however a comprehensive analysis of HP-TES coupled systems and particularly their modelling approaches remains limited. This paper classifies HP and TES technologies, highlighting their respective benefits and limitations. It further examines various HP-TES system configurations and applications, with a particular focus on modelling approaches. By providing a structured and comparative overview of available modelling methods, this review supports researchers and engineers in selecting the most suitable modelling approach based on system complexity, computational constraints, and specific objectives, facilitating the optimization of HP-TES systems for enhanced energy efficiency and sustainability.