Dueling metaphors, fueling futures: Bridge fuel visions of coal and natural gas in the United States

Since at least the 1970s, the idea that certain fossil fuels represent transitional fuels on the way to a lower-carbon energy future has persisted in energy discourse. In particular, natural gas has come to occupy a new identity in this discourse, shifting from what was once a negligible portion of the energy mix in the United States to one of the nation's most important energy resources. Though the bridge fuel metaphor was once fairly unambiguous in its meaning, the term has evolved over time to incorporate many visions of the future roles of coal and natural gas in the energy mix. To probe the variety of these meanings in public discourse, we assess the bridge fuel narrative in news articles and government publications as a means to understand the complexity and context of political debates over the unfolding future of natural gas. Using a qualitative coding scheme, we examine five different interpretations of the bridge fuel metaphor between 1988 and 2016. We argue that with its unique quality of facilitating both consensus-building and contestation, the bridge fuel metaphor's simplicity and accessibility belie its power to reveal changing expectations, values, and visions of the future of American energy.