INTRODUCTION

Centrally managed wholesale power markets operating over high‐voltage transmission grids support the steady flow of electric power from bulk power sellers to bulk power buyers, for ultimate resale and distribution to retail customers. This mission has been complicated in recent years by a dramatic surge in the availability and use of variable energy resources (VERs). A VER is a power source whose power injections into a transmission grid cannot be fully dispatched in a controlled manner to balance changes in power withdrawals or to meet other system requirements. The chapter also provides an overview of the key concepts discussed in this book. The book proposes a linked collection of swing‐contract markets whose look‐ahead horizons for designated future operating periods can range in duration from multiple years to minutes. It considers how current US RTO/ISO‐managed day‐ahead markets could gradually transition to a swing‐contract market design.