SciCombinator

Discover the most talked about and latest scientific content & concepts.

Concept: Energy conservation

672

A central aim of the “lighting revolution” (the transition to solid-state lighting technology) is decreased energy consumption. This could be undermined by a rebound effect of increased use in response to lowered cost of light. We use the first-ever calibrated satellite radiometer designed for night lights to show that from 2012 to 2016, Earth’s artificially lit outdoor area grew by 2.2% per year, with a total radiance growth of 1.8% per year. Continuously lit areas brightened at a rate of 2.2% per year. Large differences in national growth rates were observed, with lighting remaining stable or decreasing in only a few countries. These data are not consistent with global scale energy reductions but rather indicate increased light pollution, with corresponding negative consequences for flora, fauna, and human well-being.

Concepts: Light, Sun, Mass, Probability theory, Lighting, Light pollution, Order theory, Energy conservation

136

The emergence of smart devices and smart appliances has highly favored the realization of the smart home concept. Modern smart home systems handle a wide range of user requirements. Energy management and energy conservation are in the spotlight when deploying sophisticated smart homes. However, the performance of energy management systems is highly influenced by user behaviors and adopted energy management approaches. Appliance scheduling is widely accepted as an effective mechanism to manage domestic energy consumption. Hence, we propose a smart home energy management system that reduces unnecessary energy consumption by integrating an automated switching off system with load balancing and appliance scheduling algorithm. The load balancing scheme acts according to defined constraints such that the cumulative energy consumption of the household is managed below the defined maximum threshold. The scheduling of appliances adheres to the least slack time (LST) algorithm while considering user comfort during scheduling. The performance of the proposed scheme has been evaluated against an existing energy management scheme through computer simulation. The simulation results have revealed a significant improvement gained through the proposed LST-based energy management scheme in terms of cost of energy, along with reduced domestic energy consumption facilitated by an automated switching off mechanism.

Concepts: Operations research, Planning, Energy conservation, Load balancing, Scheduling algorithm, Energy management system, Least slack time scheduling, Processor affinity

48

We have proposed and successfully demonstrated a novel approach to direct conversion of mechanical energy into electrical energy using microfluidics. The method combines previously demonstrated reverse electrowetting on dielectric (REWOD) phenomenon with the fast self-oscillating process of bubble growth and collapse. Fast bubble dynamics, used in conjunction with REWOD, provides a possibility to increase the generated power density by over an order of magnitude, as compared to the REWOD alone. This energy conversion approach is particularly well suited for energy harvesting applications and can enable effective coupling to a broad array of mechanical systems including such ubiquitous but difficult to utilize low-frequency energy sources as human and machine motion. The method can be scaled from a single micro cell with 10(-6) W output to power cell arrays with a total power output in excess of 10 W. This makes the fabrication of small light-weight energy harvesting devices capable of producing a wide range of power outputs feasible.

Concepts: Electricity, Fundamental physics concepts, Mechanical engineering, Energy conversion, Potential energy, Electrical engineering, Process, Energy conservation

27

The research of the Energy Research Group (ERG) at the University of Illinois at Urbana-Champaign through the 1970s and early 1980s has recurring bouts of popularity. That research traced the flow of various energy types from nature to the final product or service, using modified economic input-output analysis. That information allowed for a comparison of alternative uses of products and services that delivered the same demand. The goal of the study was to identify the energy-conserving potential of the alternatives. Interest in that research has risen and fallen with the price of energy through three cycles now, with the current interest also encompassing materials conservation. Although the specific numerical results of this work are dated, the process by which the analysis was conducted creates, at least, a suggestion for future analysis in the arena of materials research. A review of the ERG history, including techniques pioneered for investigating the potential for energy conservation and some of the ancillary lessons learned along the way, may be of some use to those working on issues of materials conservation today. In the coming years, the most relevant research will include assessment of the socio-economic-ecological impact of technological materials conservation policies.

Concepts: Energy, Force, The Final, Potential energy, The Current, Work, Conservation of energy, Energy conservation

26

Although most people understand the threat of climate change, they do little to modify their own energy conservation behavior. One reason for this gap between belief and behavior may be that individual actions seem unimpactful and therefore are not morally relevant. This research investigates how climate change helplessness-belief that one’s actions cannot affect climate change-can undermine the moralization of climate change and personal energy conservation. In Study 1, climate change efficacy predicted both moralization of energy use and energy conservation intentions beyond individual belief in climate change. In Studies 2 and 3, participants read information about climate change that varied in efficacy message, that is, whether individual actions (e.g., using less water, turning down heat) make a difference in the environment. Participants who read that their behavior made no meaningful impact reported weaker moralization and intentions (Study 2), and reported more energy consumption 1 week later (Study 3). Moreover, effects on intentions and actions were mediated by changes in moralization. We discuss ways to improve climate change messages to foster environmental efficacy and moralization of personal energy use. (PsycINFO Database Record

Concepts: Environment, Natural environment, Heat, Climate change, Religion, Environmentalism, Conservation of energy, Energy conservation

19

Active flight requires the ability to efficiently fuel bursts of costly locomotion while maximizing energy conservation during non-flying times. We took a multi-faceted approach to estimate how fruit-eating bats (Uroderma bilobatum) manage a high-energy lifestyle fueled primarily by fig juice. Miniaturized heart rate telemetry shows that they use a novel, cyclic, bradycardic state that reduces daily energetic expenditure by 10% and counteracts heart rates as high as 900 bpm during flight. Uroderma bilobatum support flight with some of the fastest metabolic incorporation rates and dynamic circulating cortisol in vertebrates. These bats will exchange fat reserves within 24 hr, meaning that they must survive on the food of the day and are at daily risk of starvation. Energetic flexibly in U. bilobatum highlights the fundamental role of ecological pressures on integrative energetic networks and the still poorly understood energetic strategies of animals in the tropics.

Concepts: Biodiversity, Metabolism, Energy, Muscle, Heart rate, Conservation of energy, Bradycardia, Energy conservation

16

Cardiac β-myosin variants cause hypertrophic (HCM) or dilated (DCM) cardiomyopathy by disrupting sarcomere contraction and relaxation. The locations of variants on isolated myosin head structures predict contractility effects but not the prominent relaxation and energetic deficits that characterize HCM. During relaxation, pairs of myosins form interacting-heads motif (IHM) structures that with other sarcomere proteins establish an energy-saving, super-relaxed (SRX) state. Using a human β-cardiac myosin IHM quasi-atomic model, we defined interactions sites between adjacent myosin heads and associated protein partners, and then analyzed rare variants from 6112 HCM and 1315 DCM patients and 33,370 ExAC controls. HCM variants, 72% that changed electrostatic charges, disproportionately altered IHM interaction residues (expected 23%; HCM 54%, p=2.6×10(-19); DCM 26%, p=0.66; controls 20%, p=0.23). HCM variant locations predict impaired IHM formation and stability, and attenuation of the SRX state - accounting for altered contractility, reduced diastolic relaxation, and increased energy consumption, that fully characterizes HCM pathogenesis.

Concepts: Protein, Cardiology, Muscle, Actin, Myosin, Sarcomere, Hypertrophic cardiomyopathy, Energy conservation

7

To determine how urban water conservation strategies in California cities can affect water and energy conservation efforts, reduce greenhouse gas emissions, and benefit public health.

Concepts: Carbon dioxide, Climate change, Water vapor, Case study, Natural gas, Conservation of energy, Greenhouse gas, Energy conservation

4

Despite the medical, social and economic impact of obesity, only a few therapeutic options, focused largely on reducing caloric intake, are currently available and these have limited success rates.A major impediment is that any challenge by caloric restriction is counterbalanced by activation of systems that conserve energy to prevent body weight loss.Therefore, targeting energy-conserving mechanisms to promote energy expenditure is an attractive strategy for obesity treatment.Here, in order to suppress muscle energy efficiency, we target sarcolemmal ATP-sensitive potassium (KATP) channels which have previously been shown to be important in maintaining muscle energy economy. Specifically, we employ intramuscular injections of cell-penetrating vivo-morpholinos to prevent translation of the channel pore-forming subunit. This intervention results in significant reduction of KATP channel expression and function in treated areas, without affecting the channel expression in non-targeted tissues. Furthermore, suppression of KATP channel function in a group of hind limb muscles causes a substantial increase in activity-related energy consumption, with little effect on exercise tolerance. These findings establish a proof-of-principle that selective skeletal muscle targeting of sarcolemmal KATP channel function is possible and that this intervention can alter overall bodily energetics without a disabling impact on muscle mechanical function.Molecular Therapy (2015); doi:10.1038/mt.2015.21.

Concepts: Obesity, Muscle, Physical exercise, Mass, Economics, Thermodynamics, Muscular system, Energy conservation

3

Passive overconsumption is the increase in energy intake driven by the high-fat energy-dense food environment. This can be explained in part because dietary fat has a weaker effect on satiation (i.e. process that terminates feeding). Habitually active individuals show improved satiety (i.e. process involved in post-meal suppression of hunger) but any improvement in satiation is unknown. Here we examined whether habitual physical activity mitigates passive overconsumption through enhanced satiation in response to a high-fat meal.

Concepts: Metabolism, Nutrition, Fat, Food, Diet, Dieting, Food and drink, Energy conservation