Net energy analysis must not compare apples and oranges

Energy return on investment (EROI) is a critical measure of the comparative utility of different energy carriers including fossil fuels and renewables. However it must not be used to compare carriers that cannot be put to similar end-use. Additionally, combining carriers to arrive at estimates of ‘average’ or ‘minimum’ EROIs can be problematic

Energy pay-back time: methodological caveats and future scenarios

Energy pay-back time (EPBT) has almost universally been adopted as the indicator of choice to express the energy performance of photovoltaics (PV). In this paper, an in-depth review of the methodology and all underlying assumptions and conventions is presented. A prospective analysis of the potential evolution of the EPBT of PV over the next four decades is then performed, assuming optimistic grid penetration figures and taking into account expected technological improvements. Results show that combining the two opposing effects of a reduction in cumulative energy demand for PV manufacturing and an increase in grid efficiency will likely result in severely limited reductions, or even possible increases, in the EPBT of PV. This is entirely due to how EPBT is operationally defined, and it has nothing to do with the actual energy performance of PV in the future

A prospective net energy and environmental life-cycle assessment of the UK electricity grid

National Grid, the UK’s largest utility company, has produced a number of energy transition scenarios, among which “2 degrees” is the most aggressive in terms of decarbonization. This paper presents the results of a combined prospective net energy and environmental life cycle assessment of the UK electricity grid, based on such a scenario. The main findings are that the strategy is effective at drastically reducing greenhouse gas emissions (albeit to a reduced degree with respect to the projected share of “zero carbon” generation taken at face value), but it entails a trade-off in terms of depletion of metal resources. The grid’s potential toxicity impacts are also expected to remain substantially undiminished with respect to the present. Overall, the analysis indicates that the “2 degrees” scenario is environmentally sound and that it even leads to a modest increase in the net energy delivered to society by the grid (after accounting for the energy investments required to deploy all technologies)

Life-cycle carbon emissions and energy return on investment for 80% domestic renewable electricity with battery storage in California (U.S.A.)

This paper presents a detailed life-cycle assessment of the greenhouse gas emissions, cumulative demand for total and non-renewable primary energy, and energy return on investment (EROI) for the domestic electricity grid mix in the U.S. state of California, using hourly historical data for 2018, and future projections of increased solar photovoltaic (PV) installed capacity with lithium-ion battery energy storage, so as to achieve 80% net renewable electricity generation in 2030, while ensuring the hourly matching of the supply and demand profiles at all times. Specifically—in line with California’s plans that aim to increase the renewable energy share into the electric grid—in this study, PV installed capacity is assumed to reach 43.7 GW in 2030, resulting of 52% of the 2030 domestic electricity generation. In the modelled 2030 scenario, single-cycle gas turbines and nuclear plants are completely phased out, while combined-cycle gas turbine output is reduced by 30% compared to 2018. Results indicate that 25% of renewable electricity ends up being routed into storage, while 2.8% is curtailed. Results also show that such energy transition strategy would be effective at curbing California’s domestic electricity grid mix carbon emissions by 50%, and reducing demand for non-renewable primary energy by 66%, while also achieving a 10% increase in overall EROI (in terms of electricity output per unit of investment)

Prospective LCA of the production and EoL recycling of a novel type of Li-ion battery for electric vehicles

The transport sector as a whole – and within it passenger cars in particular – is currently responsible for a large share of the total greenhouse gas emissions of many developed and developing countries, and a transition to electric vehicles (EVs) is often seen as a key stepping stone towards the de-carbonization of personal mobility. Research is on-going in the continuous development and improvement of lithium ion (Li-ion) batteries, which may use a range of several different metals in conjunction with lithium itself, such as: lithium manganese oxide (LMO), lithium iron phosphate (LFP), lithium nickel cobalt manganese oxide (NCM), and lithium nickel-cobalt-aluminium oxide (NCA). Within the MARS-EV research project, a new cell chemistry has been developed and tested, using a lithium cobalt phosphate (LCP) formulation. This work presents the first life cycle assessment (LCA) for such LCP batteries, including a newly-developed hydrometallurgical battery recycling process which enables the end-of-life recovery of not only the valuable metals, but also of the graphite component, thereby avoiding the associated CO2 emissions

La Nefrologia incontra il Nursing e la Medicina Narrativa: una ricerca di triangolazione. Un nuovo approccio alla malattia

Introduction: In the late 20th Century, Kleinman and Good created Narrative Medicine (NM). In the following years, this method made its way in healthcare, reaching the peak in 2009 when R. Charon set up the first academic course of Narrative Medicine. Nevertheless, NM is still not well known and used. The main goal of this survey is attempting to understand the emotions felt by the patient while telling his/her own illness' experience and then understand whether this approach improves therapy. Methods: The survey is developed through a methodological triangulation research consisting of a qualitative part, where 24 stories selected from the first two editions of "Quirino Maggiore" National Competition were analysed through the Van Kaam method, and a quantitative research, performed through a questionnaire submitted to patients suffering from chronic kidney disease thanks to the National Association of Hemodialysis Patients (ANED) and to Onlus Santa Maria Annunziata, Bagno a Ripoli, Florence. We received responses from 219 patients between 24 September 2021 and 18 October 2021. Results: The qualitative research identified 94 expressions grouped in 10 labels in which the most representative themes come to light. Through the questionnaire we can see that most people are not familiar with Nursing and Narrative Medicine, but that they consider the relationship between patients and healthcare workers very important. Conclusions: Although it's impossible to generalize the results, we can understand that Nursing and Narrative Medicine should be more integrated into the care pathway. Furthermore, healthcare workers should be trained in a suitable way

A comprehensive assessment of the energy performance of the full range of electricity generation technologies deployed in the United Kingdom

We performed a comprehensive and internally consistent assessment of the energy performance of the full range of electricity production technologies in the United Kingdom, integrating the viewpoints offered by net energy analysis (NEA) and life cycle assessment (LCA). Specifically, the energy return on investment (EROI), net-to-gross energy output ratio (NTG) and non-renewable cumulative energy demand (nr-CED) indicators were calculated for coal, oil, gas, biomass, nuclear, hydro, wind and PV electricity. Results point to wind, and to a lesser extent PV, as the most recommendable technologies overall in order to foster a transition towards an improved electricity grid mix in the UK, from both points of view of short-term effectiveness at providing a net energy gain to support the multiple societal energy consumption patterns, and long-term energy sustainability (the latter being inversely proportional to the reliance on non-renewable primary energy sources). The importance to maintain a sufficient installed capacity of readily-dispatchable gas-fired electricity is also recognized

A comparative life cycle assessment of single-use fibre drums versus reusable steel drums

This paper deals with a comparative analysis of two different packaging and transport scenarios, which exemplifies the implications of choosing between single-use and reusable packaging. In particular, transport of a batch of chemicals by means of disposable fibre drums vs. reusable steel drums is investigated from a life cycle perspective, and the associated environmental impact in terms of Global Warming Potential, Acidification Potential, Gross Energy Requirement and solid waste generation is assessed. Results prove beyond reasonable doubt that, even in the case of durable packaging containers requiring the use of comparatively energy-intensive materials for their production, the reuse scenario is characterized by lower environmental impact indicators across the board, and as such is the most advisable and environmentally sound option