Optimal Design of Renewable Energy Systems in Low/Zero Energy Buildings

Low energy building and zero energy building have attracted increasing attention in both academic and professional fields following the ambitions of many governments in reducing building energy consumption and carbon emission. This paper presents an investigation on the optimal design of renewable energy systems in two types of buildings: Low Energy Buildings and Zero Energy Buildings. The first zero energy building in Hong Kong, namely Hong Kong Zero Carbon Building (ZCB), is taken as a reference building in this study. The TRNSYS building model is used to generate the annual cooling load profile of the building. Simplified models are developed to simulate the building energy systems including the air-conditioning systems and the renewable energy systems in Matlab while the building annual cooling load profile is taken as the input. GA (Genetic Algorithm) method and NSGA-? (Non-dominated Sorting Genetic Algorithm) approach are implemented for single objective optimization and multi-objectives optimization respectively in Matlab. Three most important design parameters, i.e., sizes of PV, wind turbine and bio-diesel generator, are chosen as the variables to be optimized. Three objectives (total cost, CO2 emission and grid stress factor) are adopted in the multi-objective optimization. They also form the objective function in the case of single objective optimization. The performances of buildings with different combinations of renewable system sizes are compared and evaluated. The effects of the two types of buildings on the design decisions of renewable energy system sizes are studied and compared. Furthermore, the uses of single objective and multi-objective optimization methods and their advantages/disadvantages in system optimization applications are discussed

Definition and Design of Zero Energy Buildings

The wide application of renewable energy system (RES) in buildings combined with numerous financial incentives on RES paves the way for future zero energy buildings (ZEB). Although the definition of ZEB still lacks a national building code and international standards, the number of ZEB projects is still increasing worldwide which seems to be the pioneer ZEB buildings. However, due to the intermittency of the renewable resources, various uncertain parameters, and dynamic electricity price from the grid, how to select the renewable energy system for buildings is one of the challenges and therefore becomes an extensive concern for both researchers and designers. In addition, questions like how to achieve the target of zero energy for different types of buildings, should the building be designed as an independent ZEB or a group of buildings to be a ZEB cluster, and how to make building owners actively involved in installing enough RES for the building are still on the air. This chapter will present a comprehensive view on several key issues related with ZEB, that is, definition, evaluation criteria, design method, and uncertainty analysis, and the penalty cost scheme is also proposed for consideration as one policy to assist the promotion of ZEB

Numerical and lab experiment study of a novel concentrating PV with uniform flux distribution

The uniform illumination profile that falls on the PV cell is good for PV output and lifespan, however the flux distribution of the concentrating PV appears to be non-uniform in most cases which is harmful for the overall performance of the concentrating photovoltaic. In order to overcome this disadvantage, a novel asymmetric compound parabolic concentrator concentrating PV with uniform flux distribution is proposed in this paper. A two-dimensional finite element model is built for electrical performance simulation of the concentrating photovoltaic module. The prototype of the concentrating photovoltaic module is manufactured and assembled to conduct the indoor lab experiment under Standard Test Condition to verify the feasibility and reliability of the model. The outdoor experiments are conducted to show the electrical performance of the concentrating photovoltaic module under the real weather condition. Then the model is used to analyze the electrical performance of the PV cell under the flux distribution created by the proposed concentrator. The results show that the electrical performance of the proposed concentrating photovoltaic module is close to that under the uniform flux distribution with the same total radiation level, which confirms that the proposed concentrator is beneficial for the PV output under concentrating illumination due to uniform flux distribution

A Review of Electricity Demand Forecasting in Low and Middle Income Countries: The Demand Determinants and Horizons

With the globally increasing electricity demand, its related uncertainties are on the rise as well. Therefore, a deeper insight of load forecasting techniques for projecting future electricity demands becomes imperative for business entities and policy makers. The electricity demand is governed by a set of different variables or “electricity demand determinants”. These demand determinants depend on forecasting horizons (long term, medium term, and short term), the load aggregation level, climate, and socio-economic activities. In this paper, a review of different electricity demand forecasting methodologies is provided in the context of a group of low and middle income countries. The article presents a comprehensive literature review by tabulating the different demand determinants used in different countries and forecasting the trends and techniques used in these countries. A comparative review of these forecasting methodologies over different time horizons reveals that the time series modeling approach has been extensively used while forecasting for long and medium terms. For short term forecasts, artificial intelligence-based techniques remain prevalent in the literature. Furthermore, a comparative analysis of the demand determinants in these countries indicates a frequent use of determinants like the population, GDP, weather, and load data over different time horizons. Following the analysis, potential research gaps are identified, and recommendations are provided, accordingly

Optimal Distribution of Renewable Energy Systems Considering Aging and Long-Term Weather Effect in Net-Zero Energy Building Design

Generation system interruptions in net-zero energy buildings (NZEBs) may result in missing the net-zero targets by a great margin. Consequently, it is significant to incorporate a realistic reliability model for renewable energy systems (RESs) that considers aging and long-term weather conditions. This study proposed a robust design optimization method that deals with the selection of RES to achieve NZEB. Different case studies were evaluated: 1. Deterministic approach; 2. Markov chain-based reliability without the aging effect; 3. Markov chain-based reliability with the aging effect. The results showed that the optimal sizes of RES, considering the aging effect, were much larger than the other two cases based on the annual energy balance. Moreover, the consideration of the aging effect on the reliability assessment of the generation system for NZEB opens a pathway for a more robust and economic design of RES

A Critical Review of Sustainable Energy Policies for the Promotion of Renewable Energy Sources

Meeting the rising energy demand and limiting its environmental impact are the two intertwined issues faced in the 21st century. Governments in different countries have been engaged in developing regulations and related policies to encourage environment friendly renewable energy generation along with conservation strategies and technological innovations. It is important to develop sustainable energy policies and provide relevant and suitable policy recommendations for end-users. This study presents a review on sustainable energy policy for promotion of renewable energy by introducing the development history of energy policy in five countries, i.e., the United States, Germany, the United Kingdom, Denmark and China. A survey of the articles aimed at promoting the development of sustainable energy policies and their modelling is carried out. It is observed that energy-efficiency standard is one of the most popular strategy for building energy saving, which is dynamic and renewed based on the current available technologies. Feed-in-tariff has been widely applied to encourage the application of renewable energy, which is demonstrated successfully in different countries. Building energy performance certification schemes should be enhanced in terms of reliable database system and information transparency to pave the way for future net-zero energy building and smart cities

Video-Assisted Informed Consent for Cataract Surgery: A Randomized Controlled Trial

Purpose. To investigate whether adding video assistance to traditional verbal informed consent advisement improved satisfaction among cataract surgery patients. Methods. This trial enrolled 80 Chinese patients with age-related cataracts scheduled to undergo unilateral phacoemulsification surgery. Patients were randomized into two groups: the video group watched video explaining cataract-related consent information and rewatched specific segments of the video at their own discretion, before receiving traditional verbal consent advisement; the control group did not watch the video. Outcomes included patient satisfaction, refusal to consent, time to complete the consent process, and comprehension measured by a ten-item questionnaire. Results. All 80 enrolled patients signed informed consent forms. Compared with the control group, members of the video group exhibited greater satisfaction (65% versus 86%, p=0.035) and required less time to complete the consent process (12.3±6.7 min versus 5.6±5.4 min, p<0.001), while also evincing levels of comprehension commensurate with those reported for patients who did not watch the video (accuracy rate, 77.5% versus 80.2%, p=0.386). Conclusion. The video-assisted informed consent process had a positive impact on patients’ cataract surgery experiences. Additional research is needed to optimize patients’ comprehension of the video

Co-targeting of FAK and MDM2 triggers additive anti-proliferative effects in mesothelioma via a coordinated reactivation of p53

Background: Improved mesothelioma patient survival will require development of novel and more effective pharmacological interventions. TP53 genomic mutations are uncommon in mesothelioma, and recent data indicate that p53 remains functional, and therefore is a potential therapeutic target in these cancers. In addition, the tumour suppressor NF2 is inactivated by genomic mechanisms in more than 80% of mesothelioma, causing upregulation of FAK activity. Because FAK is a negative regulator of p53, NF2 regulation of FAK–p53–MDM2 signalling loops were evaluated. Methods: Interactions of FAK–p53 or NF2–FAK were evaluated by phosphotyrosine-p53 immunoaffinity purification and tandem mass spectrometry, and p53, FAK, and NF2 immunoprecipitations. Activation and/or expression of FAK, p53, and NF2 were also evaluated in mesotheliomas. Effects of combination MDM2 and FAK inhibitors/shRNAs were assessed by measuring mesothelioma cell viability/growth, expression of cell cycle checkpoints, and cell cycle alterations. Results: We observed constitutive activation of FAK, a known negative regulator of p53, in each of 10 mesothelioma cell lines and each of nine mesothelioma surgical specimens, and FAK was associated with p53 in five of five mesothelioma cell lines. In four mesotheliomas with wild-type p53, FAK silencing by RNAi induced expression and phosphorylation of p53. However, FAK regulation of mesothelioma proliferation was not restricted to p53-dependent pathways, as demonstrated by immunoblots after FAK knockdown in JMN1B mesothelioma cells, which have mutant/inactivated p53, compared with four mesothelioma cell lines with nonmutant p53. Additive effects were obtained through a coordinated reactivation of p53, by FAK knockdown/inhibition and MDM2 inhibition, as demonstrated by immunoblots, cell viability, and cell-cycle analyses, showing increased p53 expression, apoptosis, anti-proliferative effects, and cell-cycle arrest, as compared with either intervention alone. Our results also indicate that NF2 regulates the interaction of FAK–p53 and MDM2–p53. Conclusions: These findings highlight novel therapeutic opportunities in mesothelioma

NudC L279P Mutation Destabilizes Filamin A by Inhibiting the Hsp90 Chaperoning Pathway and Suppresses Cell Migration

Filamin A, the first discovered non-muscle actin filament cross-linking protein, plays a crucial role in regulating cell migration that participates in diverse cellular and developmental processes. However, the regulatory mechanism of filamin A stability remains unclear. Here, we find that nuclear distribution gene C (NudC), a cochaperone of heat shock protein 90 (Hsp90), is required to stabilize filamin A in mammalian cells. Immunoprecipitation-mass spectrometry and western blotting analyses reveal that NudC interacts with filamin A. Overexpression of human NudC-L279P (an evolutionarily conserved mutation in NudC that impairs its chaperone activity) not only decreases the protein level of filamin A but also results in actin disorganization and the suppression of cell migration. Ectopic expression of filamin A is able to reverse these defects induced by the overexpression of NudC-L279P. Furthermore, Hsp90 forms a complex with filamin A. The inhibition of Hsp90 ATPase activity by either geldanamycin or radicicol decreases the protein stability of filamin A. In addition, ectopic expression of Hsp90 efficiently restores NudC-L279P overexpression-induced protein stability and functional defects of filamin A. Taken together, these data suggest NudC L279P mutation destabilizes filamin A by inhibiting the Hsp90 chaperoning pathway and suppresses cell migration