Petroleum Drilling and Production in the United States: Yield per Effort and Net Energy Analysis

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).

Creating an Energy Analysis Concept for Oil and Gas Companies: The Case of the Yakutiya Company in Russia

Recently, energy analysis has been added to Russian gas companies’ annual reporting system. This new practice indicates that corporate reports are improving their analyses by addressing energy issue and the financial efficiency of energy production. However, the use of summary energy indicators is limited in these annual reports. In this paper we review the history of energy analysis in Russia from the early USSR period to today. Under the guidance of energy return on investment (EROI), we compare energy efficiency indicators with financial efficiency coefficients. The results show that the value of the return on cost of sales (ROCS) is negative in certain instances, while the value of the energy return on cost of sales (EROCS) is extremely high under the example of the Russian energy company JSC “YATEC.” Money-based indicator values (ROCS and return on fix assets (ROFA)) fluctuate with internal company financial management goals, and from the outside depending on market prices. Meanwhile energy-based values (EROCS) remain stable. Added financial analysis and energy analysis in companies’ annual statements will supplement each other in practice and will present the full picture for company efficiency analysis.

Combined application of Life Cycle Assessment and linear programming to evaluate food waste-to-food strategies: Seeking for answers in the nexus approach

The great concern regarding food loss (FL) has been studied previously, but in an isolated way, disregarding interdependencies with other areas. This paper aims to go a step further by proposing a new procedure to assess different waste management alternatives based on the nexus approach by means of an integrated Water-Energy-Food-Climate Nexus Index (WEFCNI). The environmental profile of the waste management techniques is determined using Life Cycle Assessment (LCA) which, in combination with Linear Programming (LP), explores the optimal aggregation of weighting factors that lead to an aggregated nexus index. The management of residues from the anchovy canning industry in Cantabria (Spain) has been used as a case study, considering the three current applied alternatives: (i) valorisation of FL as animal feed in aquaculture (food waste-to-food approach), (ii) incineration of FL with energy recovery, and (iii) landfilling with biogas recovery. The last two considered the use of energy recovered to produce a new aquaculture product (food waste-to-energy-to-food scenarios). The results indicate that incineration is the best performing scenario when the nutritional energy provided by the valorisation alternative is not high enough and the valorisation technology presents the highest water consumption. Therefore, a minimisation in the consumption of natural resources is suggested in order to improve the application of circular economy within the sector. The use of the nexus index as an environmental management tool is extendable to any food system with the aim of facilitating the decision-making process in the development of more sustainable products.

Energy Return on Investment (EROI) for Forty Global Oilfields Using a Detailed Engineering-Based Model of Oil Production

Studies of the energy return on investment (EROI) for oil production generally rely on aggregated statistics for large regions or countries. In order to better understand the drivers of the energy productivity of oil production, we use a novel approach that applies a detailed field-level engineering model of oil and gas production to estimate energy requirements of drilling, producing, processing, and transporting crude oil. We examine 40 global oilfields, utilizing detailed data for each field from hundreds of technical and scientific data sources. Resulting net energy return (NER) ratios for studied oil fields range from ≈2 to ≈100 MJ crude oil produced per MJ of total fuels consumed. External energy return (EER) ratios, which compare energy produced to energy consumed from external sources, exceed 1000:1 for fields that are largely self-sufficient. The lowest energy returns are found to come from thermally-enhanced oil recovery technologies. Results are generally insensitive to reasonable ranges of assumptions explored in sensitivity analysis. Fields with very large associated gas production are sensitive to assumptions about surface fluids processing due to the shifts in energy consumed under different gas treatment configurations. This model does not currently include energy invested in building oilfield capital equipment (e.g., drilling rigs), nor does it include other indirect energy uses such as labor or services.

Unconventional Heavy Oil Growth and Global Greenhouse Gas Emissions

Enormous global reserves of unconventional heavy oil make it a significant resource for economic growth and energy security; however, its extraction faces many challenges especially on greenhouse gas (GHG) emissions, water consumption, and recently, social acceptability. Here, we question whether it makes sense to extract and use unconventional heavy oil in spite of these externalities. We place unconventional oils (oil sands and oil shale) alongside shale gas, coal, lignite, wood and conventional oil and gas, and compare their energy intensities and life cycle GHG emissions. Our results reveal that oil shale is the most energy intensive fuel among upgraded primary fossil fuel options followed by in situ-produced bitumen from oil sands. Lignite is the most GHG intensive primary fuel followed by oil shale. Based on future world energy demand projections, we estimate that if growth of unconventional heavy oil production continues unabated, the incremental GHG emissions that results from replacing conventional oil with heavy oil would amount to 4-21 Gt-CO2eq GtCO2eq over four decades (2010 by 2050). However, prevailing socio-economic, regional and global energy politics, environmental and technological challenges may limit growth of heavy oil production and thus its GHG emissions contributions to global fossil fuel emissions may be smaller.

The implications of the declining energy return on investment of oil production

Declining production from conventional oil resources has initiated a global transition to unconventional oil, such as tar sands. Unconventional oil is generally harder to extract than conventional oil and is expected to have a (much) lower energy return on (energy) investment (EROI). Recently, there has been a surge in publications estimating the EROI of a number of different sources of oil, and others relating EROI to long-term economic growth, profitability and oil prices. The following points seem clear from a review of the literature: (i) the EROI of global oil production is roughly 17 and declining, while that for the USA is 11 and declining; (ii) the EROI of ultra-deep-water oil and oil sands is below 10; (iii) the relation between the EROI and the price of oil is inverse and exponential; (iv) as EROI declines below 10, a point is reached when the relation between EROI and price becomes highly nonlinear; and (v) the minimum oil price needed to increase the oil supply in the near term is at levels consistent with levels that have induced past economic recessions. From these points, I conclude that, as the EROI of the average barrel of oil declines, long-term economic growth will become harder to achieve and come at an increasingly higher financial, energetic and environmental cost.

Energy and the U.S. Economy: A Biophysical Perspective

A series of hypotheses is presented about the relation of national energy use to national economic activity (both time series and cross-sectional) which offer a different perspective from standard economics for the assessment of historical and current economic events. The analysis incorporates nearly 100 years of time series data and 3 years of cross-sectional data on 87 sectors of the United States economy. Gross national product, labor productivity, and price levels are all correlated closely with various aspects of energy use, and these correlations are improved when corrections are made for energy quality. A large portion of the apparent increase in U.S. energy efficiency has been due to our ability to expand the relative use of high-quality fuels such as petroleum and electricity, and also to relative shifts in fuel use between sectors of the economy. The concept of energy return on investment is introduced as a major driving force in our economy, and data are provided which show a marked decline in energy return on investment for all our principal fuels in recent decades. Future economic growth will depend largely on the net energy yield of alternative fuel sources, and some standard economic models may need to be modified to account for the biophysical constraints on human economic activity.