57 research outputs found

    Investigating the importance of motivations and barriers related to microgeneration uptake in the UK

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    AbstractMicrogeneration technologies such as solar photovoltaics, solar thermal, wind and heat pumps may be able to contribute to meeting UK climate change and energy security targets, but their contribution to UK domestic energy supply remains low. This research uses a best-worst scaling survey of microgeneration adopters, considerers and rejecters (n=291) to determine the relative importance of different motivations and barriers in microgeneration (non) adoption decisions. The most important motivations are earning money from installation, increasing household energy independence and protecting against future high energy costs. Results indicate that the introduction of Feed-in Tariffs has clearly encouraged a new, more financially-motivated, group to install. Financial factors are the most important barriers and of most importance to rejecters is the prospect of losing money if they moved home. The Green Deal was introduced to reduce this barrier, but may instead exacerbate the problem as potential homebuyers are put off purchasing a home with an attached Green Deal debt. The difficulty in finding trustworthy information on microgeneration is also a major obstacle to adoption, particularly for considerers, despite efforts by the government and microgeneration interest groups to reduce this barrier. Self-sufficiency in energy is a more important motivation for those considering or having rejected installation than for adopters. Provision of accessible information and greater emphasis on household self-sufficiency in energy could help improve the uptake

    A shortened protocol for assessing cognitive bias in rats

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    Reliable measurement of affective state in animals is a significant goal of animal welfare. Such measurements would also improve the validity of pre-clinical mental health research which relies on animal models. However, at present, affective states in animals are inaccessible to direct measurement. In humans, changes in cognitive processing can give reliable indications of emotional state. Therefore, similar techniques are increasingly being used to gain proxy measures of affective states in animals. In particular, the ‘cognitive bias’ assay has gained popularity in recent years. Major disadvantages of this technique include length of time taken for animals to acquire the task (typically several weeks), negative experiences associated with task training, and issues of motivation. New method Here we present a shortened cognitive bias protocol using only positive reinforcers which must actively be responded to. Results The protocol took an average of 4 days to complete, and produced similar results to previous, longer methods (minimum 30 days). Specifically, rats housed in standard laboratory conditions demonstrated negative cognitive biases when presented with ambiguous stimuli, and took longer to make a decision when faced with an ambiguous stimulus. Comparison with existing methods Compared to previous methods, this protocol is significantly shorter (average 4 days vs. minimum 30 days), utilises only positive reinforcers to avoid inducing negative affective states, and requires active responses to all cues, avoiding potential confounds of motivational state. Conclusions We have successfully developed a shortened cognitive bias protocol, suitable for use with laboratory rats. Keywords Cognitive bias; Emotion; Affect; Rat; Protoco

    Methane emissions : choosing the right climate metric and time horizon

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    Methane is a more potent greenhouse gas (GHG) than CO2, but it has a shorter atmospheric lifespan, thus its relative climate impact reduces significantly over time. Different GHGs are often conflated into a single metric to compare technologies and supply chains, such as the global warming potential (GWP). However, the use of GWP is criticised, regarding: (1) the need to select a timeframe; (2) its physical basis on radiative forcing; and (3) the fact that it measures the average forcing of a pulse over time rather than a sustained emission at a specific end-point in time. Many alternative metrics have been proposed which tackle different aspects of these limitations and this paper assesses them by their key attributes and limitations, with respect to methane emissions. A case study application of various metrics is produced and recommendations are made for the use of climate metrics for different categories of applications. Across metrics, CO2 equivalences for methane range from 4-199 gCO2eq./gCH4, although most estimates fall between 20 and 80 gCO2eq./gCH4. Therefore the selection of metric and time horizon for technology evaluations is likely to change the rank order of preference, as demonstrated herein with the use of natural gas as a shipping fuel versus alternatives. It is not advisable or conservative to use only a short time horizon, e.g. 20 years, which disregards the long-term impacts of CO2 emissions and is thus detrimental to achieving eventual climate stabilisation. Recommendations are made for the use of metrics in 3 categories of applications. Short-term emissions estimates of facilities or regions should be transparent and use a single metric and include the separated contribution from each GHG. Multi-year technology assessments should use both short and long term static metrics (e.g. GWP) to test robustness of results. Longer term energy assessments or decarbonisation pathways must use both short and long-term metrics and where this has a large impact on results, climate models should be incorporated. Dynamic metrics offer insight into the timing of emissions, but may be of only marginal benefit given uncertainties in methodological assumptions

    Future use of natural gas under tightening climate targets

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    Natural gas has developed as a prominent energy source across the world over the last century. However, its use in the future will be constrained by evolving climate goals, and an optimal role for natural gas in a future 1.5°C world is debated. We conduct a systematic review of the literature, and analysis of the Intergovernmental Panel on Climate Change SR1.5 scenarios to understand the role of natural gas in a 1.5°C world. We also examine key factors that influence the use of gas such as Carbon Capture and Storage and Negative Emissions Technologies. We find that global gas use decreases more considerably under a 1.5°C target than 2°C with half of the 1.5°C scenarios reducing gas use by at least ∼35% by 2050 and ∼70% by 2100 against 2019 consumption. We find there is no correlation between the level of Negative Emissions Technologies and the permitted gas use in Intergovernmental Panel on Climate Change scenarios, while there is a strong correlation between gas use and the deployment of Carbon Capture and Storage. Regionally, there are considerable ranges in gas use, with the Organisation for Economic Cooperation and Development & European Union seeing the greatest decrease in use and Asia increasing use until 2050. Notwithstanding this uncertainty, global natural gas use is likely to decrease in the coming decades in response to climate goals

    Natural gas fuel and greenhouse gas emissions in trucks and ships

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    Natural gas is a transport fuel which may help reduce greenhouse gas emissions in shipping and trucks. However, there is some disagreement regarding the potential for natural gas to provide significant improvements relative to current ships and trucks. In 2015, road freight represented ~7% of global energy related CO2 emissions, with international shipping representing ~2.6% of global emissions. These emissions are also expected to grow, with some estimates suggesting road freight emission growing by a third, and shipping emissions growing by between 50% and 250% from 2012 to 2050, making absolute emissions reductions challenging. In addition, reducing emissions in ships and trucks has proved technically difficult given the relatively long distances that ships and trucks travel. This paper documents a systematic review of literature detailing well-to-wheel/wake greenhouse gas emissions and economic costs in moving from diesel and heavy fuel oil to natural gas as a fuel for trucks and ships. The review found a number of important issues for greenhouse gas reduction. First, moderate greenhouse gas reductions of 10% were found when switching to natural gas from heavy fuel oil in shipping when comparing the lowest estimates. Comparing lowest well-to-wheel greenhouse gas emissions estimates for trucks, the benefit of switching to natural gas fuel is approximately a 16% reduction in greenhouse gas emissions. However, these emissions are highly variable, driven particularly by methane emissions in exhaust gas. Given this, in the worst cases natural gas ships and trucks emit more greenhouse gasses than the diesel trucks and heavy fuel oil ships that they would replace. It appears relatively cost effective to switch to natural gas as a transport fuel in ships and trucks. However, the limited emissions reduction potential raises questions for the ongoing role of natural gas to reduce greenhouse gas emissions in line with the challenging greenhouse gas reduction targets emerging in the transport sector

    Does Environmental Enrichment Reduce Stress? An Integrated Measure of Corticosterone from Feathers Provides a Novel Perspective

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    Enrichment is widely used as tool for managing fearfulness, undesirable behaviors, and stress in captive animals, and for studying exploration and personality. Inconsistencies in previous studies of physiological and behavioral responses to enrichment led us to hypothesize that enrichment and its removal are stressful environmental changes to which the hormone corticosterone and fearfulness, activity, and exploration behaviors ought to be sensitive. We conducted two experiments with a captive population of wild-caught Clark's nutcrackers (Nucifraga columbiana) to assess responses to short- (10-d) and long-term (3-mo) enrichment, their removal, and the influence of novelty, within the same animal. Variation in an integrated measure of corticosterone from feathers, combined with video recordings of behaviors, suggests that how individuals perceive enrichment and its removal depends on the duration of exposure. Short- and long-term enrichment elicited different physiological responses, with the former acting as a stressor and birds exhibiting acclimation to the latter. Non-novel enrichment evoked the strongest corticosterone responses of all the treatments, suggesting that the second exposure to the same objects acted as a physiological cue, and that acclimation was overridden by negative past experience. Birds showed weak behavioral responses that were not related to corticosterone. By demonstrating that an integrated measure of glucocorticoid physiology varies significantly with changes to enrichment in the absence of agonistic interactions, our study sheds light on potential mechanisms driving physiological and behavioral responses to environmental change
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