• Energy Research
• 13. Climate action close
• 11. Sustainability close
• Imperial College London close

Furan based building blocks have potential of introducing new commodity chemicals at low cost with low carbon impact.

The phasing out of leaded gasoline in many countries around the world at the end of the last millennium has resulted in a complex mixture of lead sources in the atmosphere. Recent studies suggest that coal combustion has become an important source of Pb in aerosols in urban and remote areas. Here, we report lead concentration and isotopic composition for 59 coal samples representing major coal deposits worldwide in an attempt to characterize this potential source. The average concentration in these coals is 35 microg Pb g(-1), with the highest values in coals from Spain and Peru and the lowest in coals from Australia and North America. The 206Pb/207Pb isotope ratios range between 1.15 and 1.24, with less radiogenic Pb in coals from Europe and Asia compared to South and North America. Comparing the Pb isotopic signatures of coals from this and previous studies with those published for Northern and Southern Hemisphere aerosols, we hypothesize that coal combustion might now be an important Pb source in China, the eastern U.S., and to some extent, in Europe but not as yet in other regions including South Africa, South America, and western U.S. This supports the notion that "old Pb pollution" from leaded gasoline reemitted into the atmosphere or long-range transport (i.e., from China to the western U.S.) is important. Comparing the isotope ratios of the coals, the age of the deposits, and Pb isotope evolution models for the major geochemical reservoirs suggests that the PbIC in coals is strongly influenced by the depositional coal forming environment.

Downsizing the internal combustion engine has been shown to be an effective strategy towards CO2 emissions reduction, and downsized engines look set to dominate automotive powertrains for years to come. Turbocharging has been one of the key elements in the success of downsized internal combustion engine systems. The process of engine-turbocharger matching during the development stage plays a significant role towards achieving the best possible system performance, in terms of minimizing fuel consumption and pollutant emissions. In current industry practice, engine modeling in most cases does not consider the full unsteady analysis of the turbocharger turbine. Thus, turbocharged engine performance prediction is less comprehensive, particularly under transient load conditions. Commercial one-dimensional engine codes are capable of satisfactory engine performance predictions, but these typically assume the turbocharger turbine to be quasi-steady, hence the inability to fully resolve the pulsating flow performance. On the other hand, a one-dimensional gas dynamic turbine model is capable of simulating the pressure wave propagation in the model domain, thus serving as a powerful tool to analyze the unsteady performance. In addition, a mean-line model is able to compute the turbine power and efficiency through the conservation method and Euler’s Turbomachinery Equation. However, none of these modeling methods have been widely implemented into commercial one-dimensional engine codes thus far. The objective of this paper is to assess the possibility of numerically producing the steady equivalent cycle averaged turbocharger turbine maps, which could be used in commercial engine codes for performance prediction. The cycle-averaged maps are obtained using a comprehensive turbocharged engine model including accurate pulsating exhaust flow performance prediction. The model is validated against experimental results and effects of flow frequency on the maps are discussed in detail.

Abstract Energy modelling is the process of using mathematical models to develop abstractions and then seek insights into future energy systems. It can be an abstract academic activity. Or, it can insert threads that influence our development. We argue therefore, that energy modelling that provides policy support (EMoPS) should not only be grounded in rigorous analytics, but also in good governance principles. As, together with other policy actions, it should be accountable. Almost all aspects of society and much of its impact on the environment are influenced by our use of energy. In this context, EMoPS can inspire, motivate, calibrate, and ‘post assess’ energy policy. But, such modeling is often undertaken by too few analysts under time and resource pressure. Building on the advances of ‘class leaders’, we propose that EMoPS should reach for practical goals — including engagement and accountability with the communities it involves, and those it will later affect. (We use the term Ubuntu, meaning ‘I am because you are’ to capture this interdependency). We argue that Ubuntu, together with retrievability, repeatability, reconstructability, interoperability and auditability (U4RIA) of EMoPS should be used to signal the beginnings of a new default practice. We demonstrate how the U4RIA principles can contribute in practice using recent modelling of aspirational energy futures by Costa Rica as a case study. This modelling effort includes community involvement and interfaces and integrates stakeholder involvement. It leaves a trail that allows for its auditing and accountability, while building capacity and sustainable institutional memory.

A large interdisciplinary consortium of engineers, social scientists and policy analysts has developed three low-emissions, more-electric transition pathways for the UK. The approach is based on earlier work on understanding transitions, applying a multi-level perspective with landscape, regime and niche levels to the development of socio-technical scenarios. The pathways to 2050 focus on the power sector, including the potential for increasing the use of low-emissions electricity for heating and transport. Part 1 described studies of historical energy and infrastructure transitions that help to understand the dynamics and timing of past transitions. The role of large-scale and small-scale actors in the electricity sector and methods used to develop the pathways were also described. In part 2, associated technologies are evaluated to determine the choices that need to be made by UK energy policymakers and stakeholders. All three pathways are appraised in terms of their environmental performance using complementary life-cycle assessment and footprinting methods. Lessons can clearly be drawn for other industrialised nations attempting to reduce the emissions of their electricity generation systems, although local circumstances will determine country- and region-specific options.

To the Editor:Childhood blood pressure (BP) is an important predictor of hypertension and cardiovascular risk later in life1; risk factors for elevated BP in children remain mostly unknown. Ambient air pollution is associated with impaired vascular health, oxidative stress, and systemic inflammation

Abstract If intermittent renewable energy technologies such as those based on solar, wind, wave and tidal resources are eventually to supply significant shares of total energy supplies, it is crucial that the energy storage problem is solved. There are several (long-recognised) possibilities ahead including compressed air, pumped storage, further developments in batteries, regenerable fuel cells, ‘super-capacitors’ and so forth. But one that is being revisited extensively by industry and research establishments is the production and storage of hydrogen from electricity at off-peak times, and in times when there would be a surplus of renewable energy, for reuse in the electricity, gas and transport markets; short-term and even seasonal and longer-term storage is technically feasible with this option. This paper looks at the costs of the option both in the near-term and the long-term relative to the current costs of electricity and natural gas supplies. While the costs of hydrogen would necessarily be greater than those of natural gas (though not disruptively so), when used in conjunction with emerging technologies for decentralised generation and combined heat and power there is scope for appreciable economies in electricity supply. A lot will depend on innovation at the systems level, and on how we operate our electricity and gas grids and regulate our electricity and gas industries. We have also suggested that we now need to experiment more, at the commercial level, and in the laboratories, with the hydrogen option.

BECCS performance can be measured by a wide range of technical and sustainability indicators, which can be negatively correlated. An exclusive focus on BECCS technical performance – CO2 removal and electricity production, can result in negative consequences for the broader environment.