South Dakota regulators could get an updated map proposal this fall from a company behind a multistate pipeline for underground storage of carbon dioxide. As that plays out, a public-policy expert says research for these endeavors doesn't look promising.

Summit Carbon Solutions wants to capture carbon emissions from ethanol plants and move it through states such as South Dakota, to be stored underground in North Dakota. June Sekera, a visiting scholar at The New School for Social Research and a senior research fellow at Boston University's Global Development Policy Center, said there's a body of research about this technology for coal plants that cuts into arguments about its effectiveness.

"The studies have shown that process actually emits 3.4 to 4.7 tonnes of CO2 for each tonne that's captured and stored," she said. "So, it emits more carbon dioxide than it captures and stores underground."

A new report from the Institute for Energy Economics and Financial Analysis noted most large-scale projects have underperformed, with only a couple of successful ones. Another complication is this year's findings that ethanol has a higher carbon intensity than gasoline.

South Dakota's Public Utilities Commission has said Summit is altering its proposed pipeline route for the state ahead of the permit review. Summit has insisted its project will be good for the environment, but Sekera said these often are taxpayer-subsided ventures pushed by private companies. She argued there would need to be an overwhelming investment to yield any actual benefits.

"One study by Princeton shows 66,000 miles of CO2 pipelines would be needed to operate at the one-gigaton level," she said, "and the United States emits five gigatons of CO2 a year."

She added that having a maze of these pipelines around the country could also pose a safety risk.

Republican leaders, mainly in Iowa, have been proponents of the Summit project, but the Biden administration also has dedicated resources for carbon capture. Sekera said she thinks policymakers should stay on the path of proven sources such as wind and solar.

"Our resources and time should be spent elsewhere on non-carbon sources of energy," she said.

Meanwhile, the Summit project also has angered property owners, who have claimed they're being threatened with eminent domain if they don't agree to land easements.

Overseas markets could be harming forests in the U.S. Demand for wood pellets for biomass energy has increased dramatically around the world, especially in Europe where burning wood is treated as renewable energy and heavily subsidized.

The UK-based company Drax Group plans to build a 450,000 ton per year wood pellet plant in Longview.

Peter Riggs, director of the Washington state-based nonprofit Pivot Point, said the region has a productive wood sector.

"This new wood pellet plant proposed for Longview is very different," Riggs pointed out. "First of all, it's not for the domestic market, it's not making pellets for home stoves. It represents a substantial and entirely new source of wood fiber demand for export."

Riggs said much of the biomass would be bound for Asia. His organization signed a letter, along with more than 100 others in the U.S. and Canada, calling for the European Union to stop incentivizing wood burning as renewable energy.

Laura Haight, U.S. policy director for the Partnership for Policy Integrity, said despite its label as renewable energy, burning wood from forests one of the worst activities for the environment. It releases emissions when burned and removes trees that store carbon. Haight's organization also signed the letter to the European Union, urging it to no longer classify forest biomass as renewable.

"It's the money that's driving this system," Haight asserted. "If they change that policy, then this will no longer be subsidized, and we can see a better future for our forests and for our climate."

Riggs noted solar and wind energy were subsidized, and the costs have gone down dramatically. However, the same is not true for forest biomass. He emphasized plant operators have struggled to reduce the costs involved in sourcing, transporting and burning biomass fuels.

"If they're going to subsidize it, you kind of got to subsidize it forever," Riggs contended. "But with wind and solar, those are already cost-competitive."

The U.S. Department of Agriculture has awarded Iowa State University a $1.8 million grant to raise high-dollar crops in the shadow of huge solar array panels that are becoming more common across the state.

Ag researchers and energy experts are studying ways for people to benefit from investments in renewable energy beyond just clean electricity.

It's called agrivoltaics, and it couples solar farms with agricultural practices in, around and underneath huge solar panels, where the resulting shade won't allow traditional agricultural crops to grow well.

Matt O'Neill - professor in plant biology, entomology and microbiology at Iowa State - said researchers are trying what are known as horticultural crops in the shadow of the solar arrays, crops he said could grow better and also tend to be more valuable.

"It's a mix of things," said O'Neill. "It can be things like broccoli, tomatoes, squashes - but also perennial crops like strawberries and blackberries and raspberries. "

O'Neill said Iowa's corn and soybeans, known as commodity crops, need a lot of land to be grown profitably - which is why he says 70% of Iowa's landscape is planted with them.

He said the growing number of solar farms will create more available land for horticultural crops, potentially creating another avenue for people who want to get into farming on a smaller scale than commodity crops such as corn and soybeans require.

O'Neill said there is some evidence that growing horticultural crops beneath the panels creates a cooler micro-climate, allowing the solar arrays to operate more efficiently when they are producing electricity.

Anne Kimber directs the Electric Power Research Center at Iowa State. She said given all of the benefits, she wants people to understand that using farmland in multiple ways - as agrivoltaics does - will be economically and environmentally beneficial for everyone.

"But that means that we're using land in a different way for those kinds of home-grown power systems," said Kimber. "And if we can demonstrate multiple values from these projects, then it does have greater value for the state of Iowa. It has greater value to the people who see these developments happening around them."

Construction on the 1.35-megawatt solar-farm agrivoltaics test site will begin next month on 10 acres south of Ames. Research is scheduled to begin next spring.

Tucson community leaders gathered at an event to highlight opportunities to grow Arizona's clean-energy economy say it's been made more accessible through incentives in President Joe Biden's Inflation Reduction Act and the Infrastructure Investment and Jobs Act.

Tucson City Council member Kevin Dahl predicted that clean-energy incentives will not only help lower-income households in the state consider solar but will also address a previous gap in benefits for nonprofit organizations. The IRA bill allocates $20 billion for nonprofits to implement projects that cut pollution and energy costs.

"Even as the clean-energy industry has exploded in our state, a lot of Arizonans have been left out," he said. "New solar incentives, however - including a 30% tax credit off the cost of installation and another 30% for standalone battery installation - will be transformative."

Leaders have estimated an additional 150,000 Arizona households will install rooftop solar panels because of the investments present in the Inflation Reduction Act.

More solar power may also be coming to rural Arizonans, with increased funding for the Rural Energy for America Program. It provides grants and loans to farms and small businesses that invest in clean-energy technology.

Robert Neifert, director of business development for Solar Gain, Inc. and co-chair of the Arizona Solar Energy Industries Association, said he's excited about what this could mean for Arizona. He said they're already seeing an uptick in business.

"We were looking at the tax credit going down to 22 [percent], and then down to 10 [percent], and wondering what would happen to solar, in Arizona and the country," he said. "And now, it's turned the other direction and we're more excited than ever. And having 10 years of certainty is absolutely amazing."

Neifert said what is important about the clean-energy transition is that it be accomplished affordably and executed fairly. As some members of Congress try to roll back investments in clean energy, all speakers at the event shared an urgent need to continue with what they called "bold climate action."