China
Africa
Explore chapters and articles related to this topic
Nonrenewable Resources: Oil and Minerals
Published in John C. Ayers, Sustainability, 2017
Finally, the most important question about oil is not how much remains in the ground, but how much can we mine and still maintain economic and energy profits, that is, the size of the reserve (Hall and Day 2009). We get an energy profit when we get more energy from oil than the amount we use to produce it. The energy return on energy investment (EROEI) is a ratio of the energy produced by extraction to the energy consumed by extraction and transportation. As EROEI decreases, the cost per unit energy increases. The EROEI of U.S. petroleum declined from roughly 100:1 in 1930, to 40:1 in 1970, to about 14:1 in 2000 (Hall and Day 2009). For the tar sands that produce a major amount of oil consumed in the United States, the ratio is much less than 10:1, perhaps even close to 1:1. As EROEI decreases, the amount of environmental damage caused by production of each barrel of oil, including emissions of greenhouse gases, continues to rise. For example, mining of oil sands in Alberta, Canada increased the concentrations of 13 high toxicity elements in the Athabasca River; for seven of those elements, concentrations exceeded the maximum acceptable level as defined by Canada or the province of Alberta (Kelly et al. 2010).
Energy Resources
Published in Dexter Perkins, Kevin R. Henke, Adam C. Simon, Lance D. Yarbrough, Earth Materials, 2019
Dexter Perkins, Kevin R. Henke, Adam C. Simon, Lance D. Yarbrough
A major distinction between different kinds of energy sources is the energy return on energy investment, sometimes called energy return on investment (EROI), or the useful energy yield. The EROI is the ratio of useful energy provided by a resource compared with the energy it takes us to find and make the resource. Finding and producing energy and manufacturing fuel require that some energy be expended. Additionally, once produced, some kinds of energy are more efficiently used than others are. We want energy sources with high EROI values because they provide a great deal of energy and do not require much energy to produce. In contrast, some energy sources, such as most biofuels, have very low EROI.
The end of cheap oil
Published in Rauli Partanen, Harri Paloheimo, Heikki Waris, The World After Cheap Oil, 2014
Rauli Partanen, Harri Paloheimo, Heikki Waris
Energy returned on energy invested (EROEI) is the relationship between the energy invested in energy production, and the energy gained from it. For example, if a barrel of oil needs to be spent to produce four barrels of oil, the EROEI of the process is 4:1. EROEI, also sometimes called EROI, is similar to the concept of return on investment (ROI), a common concept in the investment world. EROEI is one of the most important properties of energy production in the long run. Investments are usually made on projects that have the highest ROI (on similar level of risk). Similarly, societies usually (should) invest their energy in projects that have the best return on that energy.
Building-integrated solar photovoltaic thermal (BIPVT) technology: a review on the design innovations, aesthetic values, performance limits, storage options and policies
Published in Advances in Building Energy Research, 2023
Debbarma et al. (2017) highlighted some of the special features of real-time BIPVT systems such as duct design, water-based PVT integrated into the building roofs, spiral flow passage, glazed PV with multiple, integration of PCM in window and façade-based systems and their impact on the performance. Baljit et al. (2016) reviewed the practical information regarding the installation methods and applications with a performance comparison. The information regarding the then-existing commercial producers and installers of the BIPVT system was provided. The potential manufacturers are SunDrum Solar, United States; Solvar Systems, Armenia; Meyer Burger, Switzerland; Solimpeks Corporation, Turkey; SolarWalls, Canada and Minimise Group, United States. Constructional features and performances of some of real-time BIPVT systems were detailed. This review also indicated the usefulness of economic indicators such as Return of investment (ROI), Life cycle cost (LCC), Energy payback time (EPBT), Energy return on energy investment (EROEI) and Net Energy Benefit (NEB) to assess the architectural modifications, materials and designs of the BIPVT technology.
Life cycle assessment of renewable energy technologies in Northern Africa: A critical review
Published in Energy Sources, Part A: Recovery, Utilization, and Environmental Effects, 2022
Chima Cyril Hampo, Damilola Oluwatobi Ojo, Dare Ebenezer Olatunde, Obasih Judith Isioma, Oluwatosin Omolola Oni, Adaku Jane Echendu, Musa Mathew, Modupeoluwa Abisoluwa Adediji, Seun Festus Oladipo, Peace Oluwatomisin Aro
In Algeria, an LCA study on the sustainability assessment of Ricinus communis biodiesel was carried out by Amouri et al (Amouri et al. 2017). The study analyzed the Energy Return-on-Investment (EROEI) and environmental impact of the castor bean-based biodiesel production (second-generation biodiesel). Oil extraction of the feedstock Ricinus communis was carried out utilizing transesterification with methanol. According to the study, one of the benefits of utilizing Castor is its good carbon-trading potential, as it can trap 34.6 tons of CO2 per hectare. The EROEI of the system under study was calculated to be 2.60, which is a ratio of energy output to energy input. This EROEI value from the study demonstrates that the manufacturing of castor-based biodiesel is energy viable.
Life cycle cost and energy assessment of a 3.4 kWp rooftop solar photovoltaic system in India
Published in International Journal of Ambient Energy, 2022
Sonali Goel, Renu Sharma, Bibekananda Jena
Energy return on energy investment (ERoEI) or simply energy return on investment (EROI) is the ratio of lifetime energy output to the embedded energy of the system and is given by Bhandari et al. (2015). EPBT and EROI are the two important parameters to represent the energy performance of any power generating system. For long-term viability study of any energy source, EROI is considered better than EPBT. EROI is dimensionless and tells us how much net energy is gained in its entire life time. If the EROI is less than 1:1, the system is considered not viable. The minimum EROI required in industries is 3:1 (Bhandari et al. 2015).