scholarly journals Improving Energy Transition Analysis Tool through Hydropower Statistical Modelling

Energies ◽  
2020 ◽  
Vol 14 (1) ◽  
pp. 98
Author(s):  
Cristobal Gallego-Castillo ◽  
Marta Victoria
Keyword(s):  
Path Analysis ◽  
Co2 Reduction ◽  
Energy Transition ◽  
Statistical Modelling ◽  
Analysis Tool ◽  
Renewable Electricity ◽  
Hydropower Generation ◽  
Transition Path ◽  
Transition Analysis ◽  
Regulatory Constraints

Reservoir and pumped hydro storage facilities represent one of the best options for providing flexibility at low marginal cost and very low life cycle carbon emissions. However, hydropower generation is subject to physical, environmental and regulatory constraints, which introduce complexity in the modelling of hydropower in the context of transition energy analysis. In this article, a probabilistic model for hydropower generation is developed in order to improve an hourly-resolved tool for transition path analysis presented in previous research. The model is based on time series analysis, which exploits the fact that the different constraints affecting hydropower generation were met in the past. The upgraded version of the transition path analysis tool shows a decrease in the hydropower flexibility as compared with previous published results, providing a better picture of the benefits and drawbacks associated with a specific transition path under analysis, for example in terms of assessing the probability of unserved energy. The upgraded version of the tool was employed to analyse the Spanish National Energy and Climate Plan (NECP), finding consistence between proposals associated with the power system and related CO2 reduction and share of renewable electricity targets.

Accessible Modeling of the German Energy Transition: An Open, Compact, and Validated Model

Energies ◽  
2021 ◽  
Vol 14 (23) ◽  
pp. 8084
Author(s):  
Julia Barbosa ◽  
Christopher Ripp ◽  
Florian Steinke
Keyword(s):  
Co2 Reduction ◽  
Energy Transition ◽  
Energy System ◽  
Data Sources ◽  
Partial Equilibrium ◽  
Compact Set ◽  
Transition Path ◽  
Expansion Planning ◽  
Future Developments ◽  
Historic Data

We present an easily accessible model for dispatch and expansion planning of the German multi-modal energy system from today until 2050. The model can be used with low efforts while comparing favorably with historic data and other studies of future developments. More specifically, the model is based on a linear programming partial equilibrium framework and uses a compact set of technologies to ease the comprehension for new modelers. It contains all equations and parameters needed, with the data sources and model assumptions documented in detail. All code and data are openly accessible and usable. The model can reproduce today’s energy mix and its CO2 emissions with deviations below 10%. The generated energy transition path, for an 80% CO2 reduction scenario until 2050, is consistent with leading studies on this topic. Our work thus summarizes the key insights of previous works and can serve as a validated and ready-to-use platform for other modelers to examine additional hypotheses.

scholarly journals Strategies in catalysts and electrolyzer design for electrochemical CO2 reduction toward C2+ products

2020 ◽  
Vol 6 (8) ◽  
pp. eaay3111 ◽  
Author(s):  
Lei Fan ◽  
Chuan Xia ◽  
Fangqi Yang ◽  
Jun Wang ◽  
Haotian Wang ◽  
...  
Keyword(s):  
Co2 Reduction ◽  
Value Added ◽  
Energy Transition ◽  
Economic Benefits ◽  
Renewable Electricity ◽  
Electrochemical Co2 Reduction ◽  
Fundamental Understanding ◽  
Fuels And Chemicals ◽  
Further Development

In light of environmental concerns and energy transition, electrochemical CO2 reduction (ECR) to value-added multicarbon (C2+) fuels and chemicals, using renewable electricity, presents an elegant long-term solution to close the carbon cycle with added economic benefits as well. However, electrocatalytic C─C coupling in aqueous electrolytes is still an open challenge due to low selectivity, activity, and stability. Design of catalysts and reactors holds the key to addressing those challenges. We summarize recent progress in how to achieve efficient C─C coupling via ECR, with emphasis on strategies in electrocatalysts and electrocatalytic electrode/reactor design, and their corresponding mechanisms. In addition, current bottlenecks and future opportunities for C2+ product generation is discussed. We aim to provide a detailed review of the state-of-the-art C─C coupling strategies to the community for further development and inspiration in both fundamental understanding and technological applications.

Pengaruh Good Corporate Governance Terhadap Nilai Perusahaan Dengan Variabel Intervening Profitabilitas

2017 ◽  
Vol 25 (1) ◽  
pp. 13-39
Author(s):  
Achmad Tjahjono ◽  
Siti Chaeriyah
Keyword(s):  
Corporate Governance ◽  
Path Analysis ◽  
Executive Director ◽  
Audit Committee ◽  
Positive Impact ◽  
Institutional Ownership ◽  
Analysis Tool ◽  
Manufacturing Companies ◽  
Company Value ◽  
Good Corporate Governance

The Company was founded with the goal of increasing the value of the company as well as to provide prosperity for the owners or shareholders. Good Corporate Governance and profitability is an effort to enhance company value. This study aims to determine the influence of good corporate governance to company value with profitability as intervening variable. The population of this research is manufacturing companies listed in Indonesia Stock Exchange in 2010 - 2014. The sample is taken by using purposive sampling method. Under this method, as many as 123 companies were obtained. The analysis tool to test the hypothesis is path analysis with AMOS software version 21. Data analysis method is descriptive analysis, path analysis, and sobeltest. The results of this study indicate that managerial ownership, the audit committee and the profitability have positive impact toward the of the company value, institutional ownership has positive impact but not significant, non-executive director with negative effect tendency on the company value. The results of this study also showed that profitability cannot mediate the effect of good corporate governance mechanisms on company value. It can be suggested to replace the intervening variable with other variables such as quality of earnings instead of profitability since it is declined as an intervening variable. non-executive director and institutional ownership does not contribute any positive and significant effect on company value and profitability. The following research can use another proxy in the measurement process and consider other theories that could explain comprehensively.

scholarly journals Procurement, finance and the energy transition: Between global processes and territorial realities

2021 ◽  
pp. 251484862199112
Author(s):  
Lucy Baker
Keyword(s):  
Electricity Generation ◽  
Local Level ◽  
Energy Transition ◽  
Community Empowerment ◽  
Renewable Electricity ◽  
Middle Income ◽  
Middle Income Countries ◽  
Asset Class ◽  
Renewable Electricity Generation ◽  
Utility Scale

Utility-scale renewable electricity generation is essential to decarbonisation as well as to ensuring affordable and secure electricity supplies around the world. Yet thus far there has been limited critical thinking dedicated to the complexities behind the finance and ownership of this new infrastructure and how national and local stakeholders should participate in and benefit from its development, particularly in contexts of high inequality in low- and middle-income countries. As the global renewable energy industry becomes increasingly consolidated and financialised, evidence from a number of countries suggests that despite the pro-environmental outcomes of utility-scale renewable electricity generation, the processes and institutions that procure and finance it have often failed to include or benefit individuals and communities living in the national and local vicinity. This paper therefore sets two key competing objectives of renewable electricity generation in context: as a predictable, long-term revenue stream for investors, and as a mechanism for socio-economic development and community empowerment. Building on scholarship from human geography, development studies and sustainability transitions, my analysis takes forward understandings of the role of finance in utility-scale renewable electricity generation as a key aspect of the political economy of the energy transition. In exploring the evolution of renewable electricity as a new and rapidly emerging asset class I consider how its development is increasingly determined by the frameworks and logics of finance and investment. Drawing on examples from South Africa and Mexico, I address the following questions: What are the evolving configurations and processes of finance and investment in utility-scale renewable electricity generation? How have they been facilitated? And what tensions have arisen from their implementation at the national and local level?

BUILDINGS AS ACTIVE COMPONENTS FOR GRID STABILITY

2017 ◽  
Vol 12 (4) ◽  
pp. 21-34
Author(s):  
Friedrich Sick ◽  
Ralph Füger
Keyword(s):  
Capital Investment ◽  
Heat Storage ◽  
Reactive Power ◽  
District Heating ◽  
Energy Transition ◽  
Heat Pumps ◽  
Raw Material ◽  
Analysis Tool ◽  
Active Components ◽  
Massive Structure

A successful energy transition depends on storage options in order to ensure power supply stability under a fluctuating generation of a growing share of renewable energies (RE). Battery storage is expensive and raw material intensive and therefore not suitable as a sole solution. Surplus electricity may easily be converted to heat, which can be stored inexpensively for a short term. With such simple Power-to-Heat or P2H solutions, lack of electric power cannot be offset by conventional heat storage. However, if a building or an urban quarter is heated by means of cogeneration, so-called Combined Heat and Power (CHP), or heat pumps (HP), the operation can be adjusted in such a way, that the building itself, i.e. its massive structure, serves as heat storage. Electricity generation and consumption is adjusted to the requirements of the grid (reactive power control). For the supply of a Berlin quarter, built in the 1950s and equipped with a district heating network and a CHP plant, the feasibility of the concept could be proved using dynamic building simulation as the analysis tool. Sixteen percent of the total heating consumption may useably be stored and extracted from the building structure. In absolute numbers: 73 MWh/a heat can be buffered corresponding to 34 MWh/a balancing electricity. For each square meter of living area, 3.7 kWh electrical balancing energy can be buffered in the building's thermal storage capacity. Nothing else is required than a re-programming of heating and possibly cooling controls. No capital investment is needed. Well insulated and more massive structures could show a proportion of 27% of such shifted heat.

Calculation of migration rates of vacancies and divacancies in α-Iron using transition path sampling biased with a Lyapunov indicator

2012 ◽  
Vol 1383 ◽  
Author(s):  
Massimiliano Picciani ◽  
Manuel Athènes ◽  
Mihai-Cosmin Marinica
Keyword(s):  
Time Scales ◽  
Reaction Rates ◽  
Model Potential ◽  
Analysis Tool ◽  
Path Sampling ◽  
Transition Path ◽  
Stable States ◽  
Transition Path Sampling ◽  
Reaction Rate Constants ◽  
Reactive Trajectories

ABSTRACTPredicting the microstructural evolution of radiation damage in materials requires handling the physics of infrequent-events, in which several time scales are involved. The reactions rates characterizing these events are the main ingredient for simulating the kinetics of materials under irradiation over large time scales and high irradiation doses. We propose here an efficient, finite temperature method to compute reaction rate constants of thermally activated processes. The method consists of two steps. Firstly, rare reactive trajectories in phase-space are sampled using a transition path sampling (TPS) algorithm supplemented with a local Lyapunov bias favoring diverging trajectories. This enables the system to visit transition regions separating stable configurations more often, and thus enhances the probability of observing transitions between stable states during relatively short simulations. Secondly, reaction constants are estimated from the unbiased fraction of reactive trajectories, yielded by an appropriate statistical data analysis tool, the multistate Bennett acceptance ratio (MBAR) package. We apply our method to the calculation of reaction rates for vacancy and di-vacancy migration in α-Iron crystal, using an Embedded Atom Model potential, for temperatures ranging from 300 K to 800 K.

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