Building a business case for corporate fleets to adopt vehicle-to-grid technology (V2G) and participate in the regulation service market

Thesis (M. Eng. in Logistics)--Massachusetts Institute of Technology, Engineering Systems Division, 2011.Cataloged from PDF version of thesis.Includes bibliographical references (p. 95-98).Electric (EV) and Plug-in Hybrid Electric vehicles (PHEV) continue to gain attention and market share, not only as options for consumers but also for corporate fleets. EVs and PHEVs can contribute to lower operating costs through reduced maintenance requirements and enhanced fuel economy. In addition, a fleet of EVs or PHEVs, when parked and aggregated in a sizeable number, can provide regulation services to the grid through the electricity stored in the vehicle's batteries. This opportunity is known as Vehicle-to-grid technology (V2G). This thesis evaluates the economics for V2G-enabled fleets to participate in the regulation services market. In order to build a business case for fleet managers, we constructed a 10-year cash flow model that compares the operating, infrastructure, and capital costs, as well as the revenue opportunities for EVs, PHEVs, and ICEs. To quantify potential revenues, we adapted a tool that the ISO New England has used to simulate the revenues of participants in the regulation market for an alternative energy pilot. We show that ICEs, while having the lowest retail value, actually have the greatest NPV due to their high operating costs and inability to participate in the regulation services market. EVs have the highest retail value, but due to their large battery size are able to provide the most regulation services. The opportunity for V2G is critical for the attractiveness of the EV. PHEVs offer lower V2G revenue opportunity than the EVs but have greater operational flexibility. We determined that V2G revenue potential is driven by the charger capacity and battery size and there are tradeoffs associated with these components. A larger battery and charger will generate more money from regulation services, but their high investment cost may outweigh these benefits. The correct combination of charger capacity, battery size, and state of charge (SOC) is important. If the charger capacity is too large and SOC too high or low, a small battery can be charged or depleted too quickly, hindering its ability to provide regulation services.by Andrés De los Ríos Vergara and Kristen E. Nordstrom.M.Eng.in Logistic

Capacidad de pistas de aeropuertos y congestión de tráfico aéreo - caso Aeropuerto Internacional El Dorado

ilMagíster en Ingeniería CivilMaestrí

Evaluation of a quality improvement intervention to reduce anastomotic leak following right colectomy (EAGLE): pragmatic, batched stepped-wedge, cluster-randomized trial in 64 countries

Background Anastomotic leak affects 8 per cent of patients after right colectomy with a 10-fold increased risk of postoperative death. The EAGLE study aimed to develop and test whether an international, standardized quality improvement intervention could reduce anastomotic leaks. Methods The internationally intended protocol, iteratively co-developed by a multistage Delphi process, comprised an online educational module introducing risk stratification, an intraoperative checklist, and harmonized surgical techniques. Clusters (hospital teams) were randomized to one of three arms with varied sequences of intervention/data collection by a derived stepped-wedge batch design (at least 18 hospital teams per batch). Patients were blinded to the study allocation. Low- and middle-income country enrolment was encouraged. The primary outcome (assessed by intention to treat) was anastomotic leak rate, and subgroup analyses by module completion (at least 80 per cent of surgeons, high engagement; less than 50 per cent, low engagement) were preplanned. Results A total 355 hospital teams registered, with 332 from 64 countries (39.2 per cent low and middle income) included in the final analysis. The online modules were completed by half of the surgeons (2143 of 4411). The primary analysis included 3039 of the 3268 patients recruited (206 patients had no anastomosis and 23 were lost to follow-up), with anastomotic leaks arising before and after the intervention in 10.1 and 9.6 per cent respectively (adjusted OR 0.87, 95 per cent c.i. 0.59 to 1.30; P = 0.498). The proportion of surgeons completing the educational modules was an influence: the leak rate decreased from 12.2 per cent (61 of 500) before intervention to 5.1 per cent (24 of 473) after intervention in high-engagement centres (adjusted OR 0.36, 0.20 to 0.64; P < 0.001), but this was not observed in low-engagement hospitals (8.3 per cent (59 of 714) and 13.8 per cent (61 of 443) respectively; adjusted OR 2.09, 1.31 to 3.31). Conclusion Completion of globally available digital training by engaged teams can alter anastomotic leak rates. Registration number: NCT04270721 (http://www.clinicaltrials.gov)