Benefits In Terms Of Emissions Research Articles

Integrating drones into NHS patient diagnostic logistics systems: Flight or fantasy?

Healthcare accounts for approximately 5% of emissions in developed nations, and the public healthcare provider in the United Kingdom (UK), the National Health Service (NHS), has set a target to reach net-zero emissions by 2040 without detriment to its quality of patient care. With Uncrewed Aerial Vehicles (UAVs; a.k.a. drones, UAS, or RPAS) starting to be used in healthcare systems outside the UK, there is interest in how they could be integrated into NHS operations to transport diagnostic specimens. Reflecting on a business-as-usual analysis of current NHS diagnostic specimen logistics across the Solent region (southern UK), this paper critically evaluates the practical reality of integrating UAV deliveries of this commodity, identifying the benefits and challenges that must be addressed to realise commercial services, including dangerous goods legislation, cargo stability, routing, and weather. In the analysis, 14 out of 79 surgeries could be realistically served by a 5m wingspan vertical take-off/landing (VTOL) UAV: seven directly, and seven via ground-based transfers. The results suggested that an average of 1,628 samples could be served by UAV each week, resulting in 42 flights/week with 10 taxi services to cover periods where weather limited flying. This equated to an approximate total service cost of £2,964/week if regulations develop to relax UAV personnel constraints. The introduction of UAVs reduced the marginal external costs (greenhouse gas emissions, congestion, and air pollution) by £196 per week and cut travel times to UAV served sites by 72% (weather permitting). Tailpipe emissions (excl. taxis), vehicle-kilometres travelled, and van costs were reduced by 20%, 20%, and 23% (respectively), but the overall system cost increased by 56%. Whilst this increase is likely to make the introduction of UAV services financially challenging, the benefits in terms of emissions and journey time savings may offset some of the additional cost and warrant further investigation.

The emission benefits of European integration

Simulating the implications of Brexit on the UK’s emissions embodied in trade with a multi-region input–output table exposes the benefits of European integration. Under 2014 trade volumes, technologies and energy mixes, a hard Brexit—reverting to a trade pattern between the UK and the EU prior to the European Internal Market (EIM)—would imply a rise of about 0.215Gt of CO2eq in the UK’s emissions embodied in imports. This is equivalent to a 38% rise in UK’s imported emissions in 2014 and roughly equal to the territorial emissions of the Netherlands in 2017. Substituting imports from the EU with those from the Rest of the World (RoW), under the same conditions, implies adding 0.35 kg of CO2eq, on average, to each dollar of activity imported in the UK. This underlines the emission benefits of an integrated European market abiding to common environmental standards and climate policies. Filling the gap in imports lost from the UK to the EU by stepping up production within the EIM would result in an extra 0.012Gt of CO2eq, a rather small increase when compared to the additional emissions in the UK’s imports following Brexit. Should the EU reallocate the lost imports from the UK to the RoW, a total of 0.128Gt of CO2eq would be added to the EIM imports. This exposes the environmental benefits in terms of emissions in keeping UK trade closely linked to the EU and the important role that Single Member States can play indirectly on EU’s import emissions. In terms of emissions embodied in trade, the sum of the EU market is, paradoxically and for the better, less than the sum of its individual parts.

Accelerated Reduction in SO2 Emissions from the U.S. Power Sector Triggered by Changing Prices of Natural Gas

Emissions of sulfur dioxide (SO(2)) from the U.S. power sector decreased by 24% in 2009 relative to 2008. The Logarithmic Mean Divisia Index (LMDI) approach was applied to isolate the factors responsible for this decrease. It is concluded that 15% of the decrease can be attributed to the drop in demand for electricity triggered by the economic recession, and 28% can be attributed to switching of fuel from coal to gas responding to the decrease in prices for the latter. The largest factor in the decrease, close to 57%, resulted from an overall decline in emissions per unit of power generated from coal. This is attributed in part to selective idling of older, less efficient coal plants that generally do not incorporate technology for sulfur removal, and in part to continued investments by the power sector in removal equipment in response to the requirements limiting emissions imposed by the U.S. Environmental Protection Agency (U.S. EPA). The paper argues further that imposition of a modest tax on emissions of carbon would have ancillary benefits in terms of emissions of SO(2).

Evaluation of Emission Factors for New Technology S. I. Euro 4 Cars

This research attempted to analyze the environmental impact of two available non-conventional vehicle technologies, highlighting the benefits in terms of emissions and fuel consumption reduction with respect to conventional vehicles. Moreover, tests were compared with predicted emissions of the conventional gasoline technology provided by the kinematic model developed. Results show that cold start strongly affects the emissions of CO, THC and NOX, which become very low during hot driving cycle. The existing emission model cannot be used to obtain a satisfactory prediction for hybrid car. But it could be proved that KEM emission model allows us to predict emission factor for conventional car and compressed natural gas. However, it is concluded that new experimental campaign with new technological cars might be interesting for future model developments.

Carbon dioxide removal via a membrane system in a natural gas combined-cycle plant

Gas separation using polymeric membranes is generally believed to be poorly suited for CO2 capture from gas turbine based power plants, because the high air-to-fuel ratios produce large amounts of exhaust gas containing strongly diluted CO2. The driving force for selective permeation is obtained by compressing the entire exhaust stream, resulting in a significant energy penalty. Additional energy is required for permeate compression, which is impaired by the other gases emitted with CO2. In spite of these difficulties, the present study is concerned with membrane systems, which the authors believe warrant further investigation. The attention was focused on natural gas combined cycles (NGCC), so as to have a starting point with high energy efficiency and low baseline emissions. To reduce the exhaust gases and to concentrate the CO2, the NGCC is fitted with a flue gas recirculation system, which has proven to leave plant performance substantially unaffected. The energy requirements for exhaust gas compression are reduced by introducing a heat exchanger between the compressed and residual exhaust gas and recovering heat from the latter. The membrane separator has been modeled using conservative data reported in the literature. Various configurations, such as multiple compression-expansion and multistage membrane units, are considered. Permeate compression is also modeled, so as to highlight the influence of permeate purity on this process. The results show a rather moderate performance penalty. A specific emission of 100 g CO2/kWh corresponds to 48 percent efficiency. Admittedly a CO2 separator for a power plant would be larger than any other membrane system designed for other purposes. However, the system appears technically feasible and would offer valuable benefits in terms of emissions.