David Gardiner
Principal, President

David Gardiner has more than 30 years of experience analyzing and shaping successful domestic and global clean energy and sustainability strategies in both the public and private sectors.  As principal of David Gardiner & Associates, he provides high-level strategic guidance to the corporate executives and non-profit leaders with whom the firm works. Among his principal areas of expertise are energy efficiency, clean air policy, sustainable transportation, and forest and land issues. David uses this knowledge, coupled with his strong ability to make sense of complicated issues, to help clients develop informed, thoughtful strategies that advance approaches that maximize the bottom line.

Prior to founding DGA, David served as the Executive Director of the White House Climate Change Task Force during the Clinton Administration, where he participated in development of domestic policy and in international climate negotiations. As EPA Administrator Carol Browner’s Assistant Administrator for Policy, David led EPA’s climate change efforts, as well as programs to reinvent EPA’s approaches to key sectors such as transportation, agriculture, metal finishing and real estate development. Prior to joining the Clinton administration, David was Legislative Director for the Sierra Club in Washington, DC. David has a Bachelor of Arts with honors from Harvard College.

Contact David
david@dgardiner.com, (202) 463-6363


Ryan Hodum
Vice President

Ryan Hodum has more than a decade of experience helping clients understand complex sustainability challenges and opportunities in the private and non-profit sectors. As Vice President of DGA, Ryan guides small businesses and Fortune 500 companies to make smart sustainability decisions. In addition to principal areas of expertise in energy policy, energy efficiency, and renewable energy, Ryan is a strategic thinker and possesses an innate teaching ability. Using innovative approaches to solving energy challenges, he has helped a leading global apparel manufacturer through the complex process of developing its global clean energy and sustainability strategy. For small businesses, Ryan has introduced them to renewable energy and energy efficiency opportunities and connecting businesses with energy experts such as EPA’s Energy Star program. On the non-profit side, he has helped build partnerships and alliances to advance energy policy at the federal level.

Prior to DGA, he worked at the U.S. Department of State, managing international climate conferences in India, Japan and Australia in support of a project portfolio to expand renewable energy and energy efficiency in China and India. He provided significant research assistance to the World Resources Institute on global supply chain bottlenecks in the wind turbine industry. Ryan has a Bachelor of Arts in International Relations and Hispanic Studies from the College of William and Mary, and has earned Master of Arts in Global Environmental Policy from American University. He speaks fluent Spanish.

Contact Ryan
ryan@dgardiner.com, (202) 463-6363


Jennifer Kefer
Vice President

Jennifer Kefer has over 12 years of experience providing legal and political expertise, strategic analysis, and advice to non-profits, corporations and cities on a range of projects related to climate, energy and other environmental issues. Her expertise in industrial efficiency, EPA regulations and compliance, alliance and partnership-building, and policy engagement guides her work as lead on DGA’s work for the Alliance for Industrial Efficiency. Jennifer’s extraordinary leadership and keen implementation abilities result in groups and coalitions staying on task, moving forward, and attaining their goals. As an example, she met with senior EPA officials and filed public comments on behalf of a wide range of organizations flagging concerns about deficiencies in the proposed Industrial Boiler Rule, resulting in a final rule that corrects for those deficiencies, allowing combined heat and power and waste heat recovery to count as compliance mechanisms.

Jennifer’s previous experience includes grassroots education and outreach, federal advocacy, legal research and analysis, and environmental litigation working on behalf of a range of organizations, including Environmental Defense Fund, the Center on Budget and Policy Priorities, and Earthjustice. She earned a B.A. in environmental studies at Brandeis University, a Masters of Environmental Studies at the Yale School of Forestry and Environmental Studies and a J.D. at the Yale Law School.

Contact Jennifer
jennifer@dgardiner.com, (202) 365-2194