Advanced nuclear, carbon capture and battery storage are among various energy technologies named in a joint study by former U.S. Energy Secretary Ernest Moniz and energy scholar Daniel Yergin as having "the highest breakthrough potential" to decarbonize the U.S., but only if the private and public sectors collaborate and accelerate investments in clean energy innovation.

Commissioned by the Bill Gates-led Breakthrough Energy Coalition and released Feb. 6, the joint study by Energy Futures Initiative CEO Moniz and IHS Markit Ltd. Vice Chairman Yergin identified clean energy technologies they said are essential for decarbonizing the U.S. economy by midcentury, as desired by many U.S. states committed to meeting the goals of the Paris Agreement on climate change.

The report named advanced nuclear reactors and storage and battery technologies as "high priority" clean energy technologies, along with carbon capture, use and storage; sunlight to fuels; and biological sequestration. In addition, with respect to the difficult-to-decarbonize industrial and building sectors, the study named hydrogen and various advanced manufacturing and building energy technologies, such as automation and high efficiency electric heating systems, as promising innovations.

Along with calling for increased and better targeted public sector investments across all stages of innovation, from research and development to commercial scale demonstration, and a larger role for states and city governments, the report emphasized the need for public-private partnerships across the innovation value chain. The report also recommended that the private sector step up its innovation investments from the savings created by the Trump administration's 2017 corporate tax cut and focus on testing facilities for product demonstration.

"Without the right kind of investment across the clean energy innovation chain, we're going to have problems with acceleration of these technologies," Moniz said at a Washington, D.C., event with Yergin held Feb. 6 and hosted by Politico.

The study warned that innovation difficulties, coupled with other countries' commitments to Paris climate goals and clean energy investments, also threaten to topple the U.S. as the world's leader in clean energy innovation. For instance, Moniz noted that China in 2017 invested $98 billion in renewables and $41 billion in its electric grid — double the U.S. investment.

The report also recommended that the U.S. Department of Energy revise its fuel-centric organizational structure, which Moniz and Yergin described as a product of the 1970s oil embargoes, to reflect the role electricity plays in America’s fuel infrastructure.

While Moniz and Yergin agreed that no one technology will decarbonize the power grid, they differed on whether U.S. energy markets should put a price on fossil fuel carbon emissions. Moniz said the U.S. will need to implement carbon pricing, but Yergin said that is just one pathway to decarbonization.

"In an era of low U.S. fossil-energy prices, establishing a cost advantage for clean energy is challenging," the report said. "The externalities of energy use that clean energy innovation is intended to mitigate usually are not manifest to the buyer as a cost, and the corresponding benefits of avoiding those externalities are not manifest as an economic gain."

At a separate panel discussion, Xcel Energy Inc. President, CEO and Chairman Ben Fowke cautioned that getting renewables to supply 80% or 100% of state generation mixes by 2050 — as desired by many states, such as California, Hawaii and New York — pushes the limits on how much intermittent renewable generation the power grid can handle.

Fowke said the "last 20%" of decarbonization is going to require dispatchable zero-carbon technologies, such as carbon sequestration or advanced nuclear reactors. One promising technology Fowke mentioned is passively cooled advanced nuclear, such as Fluor Corp. subsidiary NuScale Power LLC's pre-fabricated small modular reactor design being funded by the DOE and slated to have its first stackable unit built in the mid-2020s at the DOE's Idaho National Laboratory.

"I'm a big fan of the next-generation of nuclear, but I think we have to be technology agnostic [with deep decarbonization]," Fowke said. "Whatever gets us there in the most affordable way without sacrificing reliability is where I'll put my money." Fowke also stressed that new regulatory paradigms must be created to bring innovative energy technologies to market.

Lisa Jacobson, president of the Business Council for Sustainable Energy, said the marketplace needs to be aligned with regulatory and innovative changes so price signals support the financing of those new innovative technologies. Jacobson also noted that the DOE already helps drive innovation by highlighting best practices in technology policies, business models and private-public partnerships, as well as by identifying ways to reduce costs. When all of those things come together, she said, the U.S. energy industry finds innovative opportunities.