Authors' Summary: This book demonstrates how robust and evolving science can be relevant to public discourse about climate policy. Fighting climate change is the ultimate societal challenge, and the difficulty is not just in the wrenching adjustments required to cut greenhouse emissions and to respond to change already under way. A second and equally important difficulty is ensuring widespread public understanding of the natural and social science. This understanding is essential for an effective risk management strategy at a planetary scale. The scientific, economic, and policy aspects of climate change are already a challenge to communicate, without factoring in the distractions and deflections from organized programs of misinformation and denial. 

Here, four scholars, each with decades of research on the climate threat, take on the task of explaining our current understanding of the climate threat and what can be done about it, in lay language—importantly, without losing critical  aspects of the natural and social science. In a series of essays, published during the 2020 presidential election, the COVID pandemic, and through the fall of 2021, they explain the essential components of the challenge, countering the forces of distrust of the science and opposition to a vigorous national response.  

Each of the essays provides an opportunity to learn about a particular aspect of climate science and policy within the complex context of current events. The overall volume is more than the sum of its individual articles. Proceeding each essay is an explanation of the context in which it was written, followed by observation of what has happened since its first publication. In addition to its discussion of topical issues in modern climate science, the book also explores science communication to a broad audience. Its authors are not only scientists – they are also teachers, using current events to teach when people are listening. For preserving Earth’s planetary life support system, science and teaching are essential. Advancing both is an unending task.

Abstract: This article evaluates the optimum economic hourly dispatch in hydro-thermal systems with massive integration of variable renewable energy, wind and solar. A linear optimization model, Elemod, makes it feasible to analyze the power system operation with hourly time step, taking into account one year of planning horizon much larger than the weekly horizon that usually sets the hydro-thermal scheduling studies. We propose an alternative formulation for pumped-hydro storage, in a way that the total annual system cost is minimized with the co-optimization of the hourly PHS operation cost.

To illustrate the methodology and modelling application, presenting a real system analysis, the Brazilian Hydro-thermal System was chosen to be simulated based on its planned capacity stepping into 2029. At the end, the paper shows the ability of the PHS system to provide hourly capacity to the power system, as well as to better allocate VRE generation and manage the bulk of transmission system usage. The cost reduction could be about 14 Million R$ of the total operation cost estimated for the 2029-power system capacity.