Advancing Contracting in Energy Storage Working Group

The Advancing Contracting in Energy Storage (ACES) Working Group is an independent industry led and funded effort founded to develop a best practice guide for the energy storage project development community. To help make this Best Practice Guide possible, over 70 different companies and organizations contributed generously in the form of content, counsel, and expertise.

The goal of the ACES Working Group is to develop a library of educational resource to improve the understanding of those lending-to-, active-in, and customers-of the emerging energy storage project development market. The library of educational resources will be in the form of a “Best Practice Guide.” This Guide will be focused resources on individual topics and documents required in a project development effort. The development of the Best Practice Guide was guided by asking a simple question: What do you need to do your job better, faster, and cheaper?

This Best Practice Guide is designed to support more flexible and appropriate use of energy storage assets for new and innovative applications by improving the quality of project documentations through providing deeper insights and suitable examples that have been deemed acceptable and valuable by the lending community.


The ACES Working Group was formed in 2018 to document existing energy storage expertise and best practices to improve project development and financing efforts across the energy storage industry. Through this combined effort, the ACES Working Group developed a library of educational resources to strengthen the fundamental understand ing of energy storage project development for those developing and investing in energy storage projects.

This Best Practice Guide (Guide or BPGs) covers key aspect areas of an energy storage project proposal. Each BPG contains three to seven chapters, and each chapter follows the same format for systematic coverage, and ease of navigation. This Guide documents the industry expertise of leading firms, covering the different project components to help reduce the internal cost of project development and financing for both project developers and investors.

The Guide is structured in a standard outline format so that no matter what their background or familiarity with the subject, readers will be able to grasp important aspects of energy storage more quickly and have at hand a library of useful resources for future reference.

Each BPG was developed by committees of subject matter experts to document and organize available expertise on different project components. Committee Coordinators were responsible for ensuring the development of all chapters in their individual BPG. Chapter Leads were responsible for coordinating the necessary effort required to write and produce BPG chapters.

The objective of the ACES Working Group is twofold:

Help project developers craft higher quality project development packages more quickly and inexpensively; and help investors reduce their time reviewing proposals through their evaluation process.

ACES Best Practice Guide
Click to read report

While project developers may be familiar with the many parts comprising a project package, they are, however, often unsure as to how energy storage systems will impact each part. For their part, investors interested in the returns predicted from energy storage projects are often hesitant to invest because legal, financial and regulatory guidelines have not been clearly defined, detailed, and explained.

This guide is structured so that all reader, no matter their background or familiarity with the subject, can:

  1. Understand the issues and challenges that exist for energy storage,
  2. Benefit from current industry insights and
  3. Know where to turn for additional resources

Firm and groups involved in the ACES Working Group

Legal Counsel
Advisory Board
Investor Review Board
Participating Firms

Photos courtesy of Key Capture Energy