Ventilation in domestic buildings can have a significant impact on energy consumption but it is notoriously difficult to quantify, requiring physical test methods that are cumbersome and costly to ...apply. Energy demand reduction analyses routinely neglect the impact of ventilation and so offering well balanced advice for specific households is not possible. This paper describes a simple steady-state, heat-balance calculation method that is supplemented with monitoring data to model the effectiveness of reducing ventilation rates to minimum standards for individual homes. A key step is to determine the daily mean air change rate and the method is shown to yield plausible estimates that can then be used to establish the impact on energy demand. The benefits of the approach include improved energy demand disaggregation, customised energy demand reduction assessment and offers a means to underpin the development of better models of ventilation for building performance analysis.
Left: results from the Hybrid Heat Balance calculation of air change rates in four households (blue) compared to the predictions from BREDEM (orange). Right: the total annual energy consumption is shown by the dark blue bar, the light blue bar top right indicates the proportion of the total that is electrical consumption. The other light blue bar (bottom-left) shows the impact of minimising ventilation on energy consumption and the green bar is the resultant consumption after a number of energy demand reduction measures have been applied. Display omitted
•A steady-state, heat-balance approach for the determination of air change rate is described.•Individualised ventilation energy demand dissaggregation is demonstrated on a sample of homes.•Customised energy demand reduction analysis is presented.•The sensitivity of the method to the variability, magnitude and characteristics of ventilation on energy consumption demonstrated.
When using measurement data for monitoring there is often a desire for steady-state analysis. On-line condition monitoring and fault detection systems are typical applications where the traditional ...way of treating transient data is to remove it using methods that require tuning using thresholds. This paper suggests an alternative approach where the uncertainty estimate in a particular variable is increased in response to the presence of transients and through propagation, varies the uncertainty in the result accordingly. The formulation of the approach is described and applied to two examples from building HVAC systems. The approach is demonstrated to be a pragmatic tool that can be used to increase the robustness of calculations from time series data.
•GB domestic heat pump electricity demand in 2050 is modelled.•Modelling is based on monitored data from heat pumps and gas boilers in homes.•Uptake of heat pumps in all homes more than doubles peak ...GB electricity demand.•Moderate improvements in HP performance and dwelling fabric reduce peak GB demand.•Flexibility in DHW and space heating provision also reduce peak GB demand.
To meet net zero carbon targets by 2050s, countries with cold winters, such as Great Britain (GB), will turn to low carbon domestic heating systems such as electric heat pumps.
In this paper, a statistical model is developed using measured performance data from over 550 heat pumps installed in GB homes in 2012. The model is used to predict the additional load on the GB electricity generation and distribution infrastructure for various current and future (2050) climates, dwelling energy efficiencies and heat pump deployment scenarios.
For a cold year in the 2020s, a 100% uptake of heat pumps in the existing GB dwelling stock gave a peak electricity demand for the heat pumps of 78 GW and an annual electricity demand of 189 TWh. When added to the other, existing electricity demand, this represents an increase in the GB peak electricity demand in excess of 100% and an annual electricity demand increase of around 60%. Making reasonable assumptions about heat pumps’ future efficiency and use, and the future climate and dwelling stock fabric efficiency, and assuming 80% heat pump uptake and no load shifting, the peak heat pump electricity demand for a cold year in the 2050s halved to 37 GW. By shifting demand for water and space heating the 2020s cold year peak demand reduced by 15%.
The work provides a more robust estimate of future GB heat pump electricity demands than any previously available. The predicted future ramp rates, peak and annual total electricity demands, are lower than predicted by previous analysts.
Reducing energy demand in the domestic sector will be an important feature of future energy systems but is challenging to achieve in practice. Solutions lie in a range of building fabric and system ...improvements as well as adopting more sustainable routines and conceptions of normality in the home. The impact of such measures has so far been quantified without considering the willingness of the householder to adopt them. This paper uses a modelling approach to evaluate the effectiveness of technical and lifestyle measures to reduce energy demand in six households based on monitoring data and insights from interviews. The results are benchmarked against estimated tailored 2050 reduction targets and demonstrate that although these targets are achievable in the studied homes, householders might not always be willing to apply them. The resultant reduction pathways are shown to vary significantly between households, suggesting that bespoke strategies are needed to allow households to identify and select the most appropriate methods that allow them to maximize demand reduction.
Building three dimensional objects in sequential layers is a technique employed by Rapid Manufacturing processes which allow great freedom in the design of the manufactured component. Niche markets ...for these technologies are continually developing and they challenge conventional methods of design and procurement. In the last few years there have been large scale processes for construction applications developed based on Rapid Manufacturing principles. These processes offer construction automation, the promise of design freedom and the possibility of building in additional functionality into structures. This paper explores the issues surrounding design, data and process in terms of the impact Rapid Manufacturing has had on conventional manufacturing. Large scale processes for construction are described and these issues are then used as the basis for considering the impact these machines may have on the design and production of construction components.
Trying to remember something now typically improves your ability to remember it later. However, after watching a video of a simulated bank robbery, participants who verbally described the robber were ...25% worse at identifying the robber in a lineup than were participants who instead listed U.S. states and capitals—this has been termed the "verbal overshadowing" effect (Schooler & Engstler-Schooler, 1990). More recent studies suggested that this effect might be substantially smaller than first reported. Given uncertainty about the effect size, the influence of this finding in the memory literature, and its practical importance for police procedures, we conducted two collections of preregistered direct replications (RRR1 and RRR2) that differed only in the order of the description task and a filler task. In RRR1, when the description task immediately followed the robbery, participants who provided a description were 4% less likely to select the robber than were those in the control condition. In RRR2, when the description was delayed by 20 min, they were 16% less likely to select the robber. These findings reveal a robust verbal overshadowing effect that is strongly influenced by the relative timing of the tasks. The discussion considers further implications of these replications for our understanding of verbal overshadowing.
A methodology for the encoding of the chromosome of a genetic algorithm (GA) is described in the paper. The encoding procedure is applied to the problem of automatically generating fuzzy rule-based ...models from data. Models generated by this approach have much of the flexibility of black-box methods, such as neural networks. In addition, they implicitly express information about the process being modelled through the linguistic terms associated with the rules. They can be applied to problems that are too complex to model in a first principles sense and can reduce the computational overhead when compared to established first principles based models. The encoding mechanism allows the rule base structure and parameters of the fuzzy model to be estimated simultaneously from data. The principle advantage is the preservation of the linguistic concept without the need to consider the entire rule base. The GA searches for the optimum solution given a comparatively small number of rules compared to all possible. This minimises the computational demand of the model generation and allows problems with realistic dimensions to be considered. A further feature is that the rules are extracted from the data without the need to establish any information about the model structure a priori. The implementation of the algorithm is described and the approach is applied to the modelling of components of heating ventilating and air-conditioning systems.
This book provides a comprehensive and detailed critical analysis in English of the tourism industry in Mallorca. With origins in the end of the nineteenth century, the emphasis is on the development ...of mass tourism since the mid-1950s and the attempts to manage its environmental impact and to introduce diversification into the market.
Purpose - Limitations in traditional manufacturing methods currently employed in the production of acoustic devices, restricts the development of design led performance improvements. These devices ...are used to control sound energy and are commonly employed for tailoring room acoustics. solid freeform fabrication allows the production of acoustic structures more complex than traditionally manufactured devices. This paper aims to focus on a novel absorber based on destructive interference, considering performance, design and manufacture.Design methodology approach - Selective laser sintering has been used in the investigation of the performance and manufacturing possibilities and limitations of a novel destructive interference absorber. Validation of the absorber performance is benchmarked against a conventional resonant absorber and compared to published results. The implications for acoustic devise design, the advances and limitations in manufacture using solid freeform fabrication techniques and potential applications are discussed.Findings - An original absorber design has been shown to exhibit comparable acoustic absorption to that of a traditional solution. The nature of the geometry of the novel absorber demonstrates that the design flexibility afforded by solid freeform fabrication processes holds potential for applications incorporating new types of acoustic absorber. The use of solid freeform fabrication has demonstrated its potential to the application of acoustics, and has highlighted limitations due to post-processing, material strength and the precision of the selectivity process.Practical implications - Solid freeform fabrication techniques enable a new family of specifically engineered acoustic absorbers capable of incorporating performance benefits over conventional absorbers.Originality value - This paper focuses on room acoustic applications, the creation of high performance, conformal absorbers, applicable to a wide range of applications within the aerospace, automotive and construction industries, where space, weight and performance are key criteria.
The Master from Mountains and Fields is a fully annotated
translation of the prose texts from the "collected works" of Sŏ
Kyŏngdŏk (1489-1546), an influential Confucian scholar from the
early Chosŏn ...period (1392-1910). A native of Songdo (also known as
Kaesŏng) in present-day North Korea, Sŏ has loomed large in the
Korean cultural imagination and appeared as an exceptional sage and
popular hero in numerous tales, dramas, and films, yet his writings
are little known outside the academic milieu. Also called Master
Hwadam, Sŏ embodied an archetype of the secluded scholar who
remains hidden in "mountains and forests" to devote himself to his
studies. Held in esteem in both South and North Korea today (a
notable exception in contemporary studies on Chosŏn
Neo-Confucianism), Sŏ and his ideas about Vital Energy influenced
the great Korean Neo-Confucian debates of the sixteenth and
seventeenth centuries surrounding the psychophysiological origins
of morality as well as various non-orthodox intellectual trends in
the late Chosŏn. His thought is fundamentally rooted in the
cosmology based on the exegesis of the Book of Changes and follows
the teachings of various early Chinese Neo-Confucian thinkers; it
presents a vivid example of the eclectic nature of ideas and
intellectual trends coexisting within what is generically called
Neo-Confucianism out of convenience. This volume presents the first
English translation of all prose writings attributed to Sŏ and most
of the peritexts from his posthumously published collection Hwadam
chip. It reflects the importance of literary compilations (munjip)
in the intellectual history of Chosŏn and the complex process of
the making of Confucian masters in Korea. Sŏ's prose works are
concise and diverse and offer a glimpse at an author who thwarts
stereotyping; an introduction and annotations provide further
context. The lengthy endnotes that accompany each text make this a
useful handbook for anybody interested in Chosŏn Korea and
Confucianism, from students in East Asian and Korean studies to
specialists in literary Chinese (hanmun) or East Asian intellectual
history.
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