• Energy Research
• Open Access close
• Restricted close
• GB close
• EU close

AbstractGreenhouse gas emissions from fertiliser production are set to increase before stabilising due to the increasing demand to secure sustainable food supplies for a growing global population. However, avoiding the impacts of climate change requires all sectors to decarbonise by a very high level within several decades. Economically viable carbon reductions of substituting natural gas reforming with biomass gasification for ammonia production are assessed using techno-economic and life cycle assessment. Greenhouse gas savings of 65% are achieved for the biomass gasification system and the internal rate of return is 9.8% at base-line biomass feedstock and ammonia prices. Uncertainties in the assumptions have been tested by performing sensitivity analysis, which show, for example with a ±50% change in feedstock price, the rate of return ranges between −0.1% and 18%. It would achieve its target rate of return of 20% at a carbon price of £32/t CO2, making it cost competitive compared to using biomass for heat or electricity. However, the ability to remain competitive to investors will depend on the volatility of ammonia prices, whereby a significant decrease would require high carbon prices to compensate. Moreover, since no such project has been constructed previously, there is high technology risk associated with capital investment. With limited incentives for industrial intensive energy users to reduce their greenhouse gas emissions, a sensible policy mechanism could target the support of commercial demonstration plants to help ensure this risk barrier is resolved.

Objectives Never-smoking women in Xuanwei (XW), China, have some of the highest lung cancer rates in the country. This has been attributed to the combustion of smoky coal used for indoor cooking and heating. The aim of this study was to evaluate the spectrum of cause-specific mortality in this unique population, including among those who use smokeless coal, considered ‘cleaner’ coal in XW, as this has not been well-characterised. Design Cohort study. Setting XW, a rural region of China where residents routinely burn coal for indoor cooking and heating. Participants Age-adjusted, cause-specific mortality rates between 1976 and 2011 were calculated and compared among lifetime smoky and smokeless coal users in a cohort of 42 420 men and women from XW. Mortality rates for XW women were compared with those for a cohort of predominately never-smoking women in Shanghai. Results Mortality in smoky coal users was driven by cancer (41%), with lung cancer accounting for 88% of cancer deaths. In contrast, cardiovascular disease (CVD) accounted for 32% of deaths among smokeless coal users, with 7% of deaths from cancer. Total cancer mortality was four times higher among smoky coal users relative to smokeless coal users, particularly for lung cancer (standardised rate ratio (SRR)=17.6). Smokeless coal users had higher mortality rates of CVD (SRR=2.9) and pneumonia (SRR=2.5) compared with smoky coal users. These patterns were similar in men and women, even though XW women rarely smoked cigarettes. Women in XW, regardless of coal type used, had over a threefold higher rate of overall mortality, and most cause-specific outcomes were elevated compared with women in Shanghai. Conclusions Cause-specific mortality burden differs in XW based on the lifetime use of different coal types. These observations provide evidence that eliminating all coal use for indoor cooking and heating is an important next step in improving public health particularly in developing countries.

The natatorium’s ventilation problem receives much concern because of its large wet load. The outdoor humidity ratio in transition season is the basic design parameter of the ventilation calculation, directly affecting the rationality of architectural design. At present, the ventilation-curve (V-C) method is the most widely used method to determine the outdoor humidity ratio in the transition season in China. However, due to failing to reflect non-guaranteed hours, the rationality of this value is difficult to assess by employing this approach. This paper presents a new method, the typical transition season method (TTS), for determining the outdoor humidity ratio in the transition season of a natatorium. The TTS method selects the transition season based on the typical meteorological year (TMY) data and calculates the outdoor humidity ratio with multiple non-guaranteed hours. This can well-represent the local perennial climate characteristics and clearly reflect the non-guaranteed hours. In this study, through selecting six typical representative cities in China, the evaluation of the outdoor humidity ratio is achieved through calculating ventilation volume and air change rate, verifying the rationality of this method. The results show that the humidity ratio obtained by the V-C method is lower than that obtained by the TTS method at about 2 g/kg without guarantee of 200 h humidity ratio, and even that the maximum difference is 6.64 g/kg. Meanwhile, the validation results of the ventilation calculation show that the humidity ratio determined by the V-C method cannot meet the minimum design requirements in five cities, while the humidity ratio obtained by the TTS method cannot meet the requirements in only one city.

For future landscapes to be sustainable, significant changes in land-use and management practices will be needed. This article argues that landscape archaeology can make distinctive contributions t...

AbstractThe impacts of the changing climate on the biological world vary across latitudes, habitats and spatial scales. By contrast, the time of day at which these changes are occurring has received relatively little attention. As biologically significant organismal activities often occur at particular times of day, any asymmetry in the rate of change between the daytime and night‐time will skew the climatic pressures placed on them, and this could have profound impacts on the natural world. Here we determine global spatial variation in the difference in the mean annual rate at which near‐surface daytime maximum and night‐time minimum temperatures and mean daytime and mean night‐time cloud cover, specific humidity and precipitation have changed over land. For the years 1983–2017, we derived hourly climate data and assigned each hour as occurring during daylight or darkness. In regions that showed warming asymmetry of >0.5°C (equivalent to mean surface temperature warming during the 20th century) we investigated corresponding changes in cloud cover, specific humidity and precipitation. We then examined the proportional change in leaf area index (LAI) as one potential biological response to diel warming asymmetry. We demonstrate that where night‐time temperatures increased by >0.5°C more than daytime temperatures, cloud cover, specific humidity and precipitation increased. Conversely, where daytime temperatures increased by >0.5°C more than night‐time temperatures, cloud cover, specific humidity and precipitation decreased. Driven primarily by increased cloud cover resulting in a dampening of daytime temperatures, over twice the area of land has experienced night‐time warming by >0.25°C more than daytime warming, and has become wetter, with important consequences for plant phenology and species interactions. Conversely, greater daytime relative to night‐time warming is associated with hotter, drier conditions, increasing species vulnerability to heat stress and water budgets. This was demonstrated by a divergent response of LAI to warming asymmetry.

Analysis of coal-bearing strata in the Paleocene Firkanten Formation in the Central Tertiary Basin of Spitsbergen (Svalbard) has shown that deposition was in a coastal plain setting. Interpretation of numerous cores indicates that deposition occurred in coastal plain mires, lagoons, tidal inlets, barrier bars and shoreface environments. These form a series of shallowing-up successions metres to tens of metres thick. Correlation between boreholes over distances in excess of 100 km proved challenging with no regional marker horizons. However, by constructing paleogeographic maps as part of the process of correlating, and by using analogous modern coastal areas as indicators of facies belt widths, a correlation scheme that provides patterns of facies distribution that are consistent in three dimensions has been created. The resulting stratigraphic framework comprises parasequences grouped into parasequence sets that show an overall retrogradational pattern representing a stepwise transgression over a basin floor that was subsiding due to flexural subsidence. Absence of incision or other evidence for relative sea-level fall within the whole succession suggests that flexural subsidence was sufficient to keep pace with eustatic sea-level falls. The basal unconformity surface is overlain by a poorly sorted deposit of reworked regolith that forms a strongly diachronous unit, occurring at the base of successive parasequences. Individual parasequences formed in response to relative sea-level rises that are considered likely to be eustatic in origin and resulted in flooding of the coastal plain. Centimetre-scale analysis of the coal maceral distribution through the thickness of the lowermost major coal seam indicates that there were also higher-frequency fluctuations of relative sea level, possibly at Milankovitch-scale, during the deposition of individual parasequences. This new facies model and interpretation of the subsidence history of the basin provides a framework for understanding the distribution of sediments within a coal-bearing coastal plain succession.

Eggshell is a cheap and environmentally friendly waste stream from the food industry, which could be potentially used for different applications in a circular economy scenario. Carbonation of eggshell derived sorbents has been investigated for calcium looping high temperature applications. Nevertheless, the application of these sorbents for direct air capture is yet to be explored in detail. In this work, waste eggshell (ES) and three different ethanol/water treated eggshell samples (E70, E80 and E90) are assessed for direct air capture and compared to limestone. These samples are exposed to ambient air in two distinct conditions. Namely, i) ambient air at 25 °C in a laboratory and ii) refrigerator conditions at 4 °C in order to simulate how these sorbents might perform in different climatic scenarios for varying geographic areas. Carbonation and hydration conversions were calculated for times of ∼ 3000 h. It was found that treating the eggshells with ethanol was key in order to obtain a suitable material for this application. Two of the ethanol-treated samples obtained similar conversions in comparable amounts of time for ambient air conditions, while limestone still performed better in refrigerator conditions