In the six weeks since Russia invaded Ukraine, the conflict has not only sent energy prices soaring, but has disrupted food production, pushing costs upward and stoking fears of global food shortages. 

The United Nations has warned of surging food insecurity in countries that depend on wheat from Ukraine, a critical and major breadbasket. Many of them were already teetering on the edge of hunger before the crisis.

As these effects of the conflict ripple across the globe, the world is seeing how energy and food markets are crucially linked. Just a couple of examples: 

Farmers everywhere are scrambling to buy fertilizer, which has become exorbitantly expensive and scarce as prices for natural gas to make it have shot up. And vegetable growers in the U.K. say that energy prices are so high they can’t afford to heat their greenhouses, meaning less fresh produce in coming months. 

Meanwhile, the Biden administration is considering expanding the use of ethanol, made from corn, in an attempt to lower fuel prices—but at the risk of raising food prices.

“Food and energy markets are going through the roof at the moment,” said Tim Benton, director of the Environment and Society Programme at Chatham House, the U.K.-based think tank, in a recent call with reporters. “The key question for those of us who are interested in sustainability is whether nature will be sacrificed in order to boost food production or whether climate will be sacrificed in order to boost energy production.”

As the Russia-Ukraine conflict draws the relationship between energy and agriculture into sharp relief, it also reframes a long standing and related question over biofuels: Should the world’s finite agricultural land be used to grow fuel rather than food, especially when the planet faces the intertwined crises of growing hunger and climate change? 

“There is less land than there is demand for the goods that come from the land,” Benton said.

Today, the grain consumed by the U.S. and Europe to produce biofuels is twice what Ukraine exports in a year. 

Some researchers say there’s not enough cropland to support the food needs of a growing global population and grow biofuels without gobbling up land that should be left as forest or native vegetation, enabling it to store more carbon.

“Every climate strategy requires that we stop expanding agricultural land,” said Tim Searchinger, a senior research scholar at the Princeton School of Public and International Affairs and senior fellow at the World Resources Institute. “But the world is expanding agricultural land at a record rate.”

In the European Union, roughly 10 percent of cropland is already used for biofuels. But the EU’s plan to restore more carbon and biodiversity in Europe—a plan known as Fit for 55, which is currently being debated—depends on an expansion of biofuels and the cropland to grow them, Searchinger says in a new analysis.

“We’re relying on Europe to reduce their demand for land,” Searchinger said. “Yet they’re going to increase their demand for land.”

Searchinger says that the EU models estimate that nearly 55 million more acres will be needed to grow biofuels by 2050—or about one-fifth of Europe’s cropland.

The policy, Searchinger says, will not only consume European land that should be restored to carbon-storing forests, it could accelerate deforestation in countries beyond Europe. That’s because Europe already imports food produced on nearly 60 million acres of foreign land, causing a release of about 400 million tons of carbon dioxide every year. 

The problem, Searchinger says, is that the EU calculations don’t acknowledge that land has a “carbon opportunity cost.” They assume that if biofuels are produced and burned in one place, they don’t displace land and carbon elsewhere.

“Instead of using the land to help feed the world, or at least avoid raiding the rest of the world, they’re going to pretend they have a surplus and use their land for bioenergy,” Searchinger said. “It’s not that different from shipping your steel mills to China and saying you’ve reduced your greenhouse gas emissions.”

Over the past decade, global cropland has expanded by nearly 30 million acres. At that rate, an area the size of India will be converted from forests and savannas to farmland by 2050. Much of that projected conversion will happen because of continued demand for high-carbon foods— milk and meat—from developing countries. 

Like in the U.S., the EU has already developed much of its available cropland and has a highly industrialized and resource-gobbling food system. That means, Searchinger said, that these countries also have an opportunity to significantly reduce their carbon footprint from agriculture. 

If Europe cut back on milk and meat consumption and intensified production on existing cropland, it could “spare” 110 million acres of land from farming, allowing it to instead be left natural to store carbon, Searchinger found.

The same rationale could apply in the U.S., where croplands to grow biofuels have expanded.  A recent study found that U.S. biofuels mandates increased corn production onto nearly 7 million acres. That land conversion, the authors said, contributed to significant greenhouse gas emissions and made corn-based ethanol more carbon-intensive than gasoline.

Some researchers have questioned the estimates of emissions from converting land to biofuels production.

“It all depends on what the land would have been used for were it not used for biofuels,” said Bruce Babcock, a professor of public policy at the University of California, Riverside, and a biofuels expert. “That’s an impossible counterfactual to estimate.”

But Babcock agrees that mandates distort farmers’ choices. “They’re going to switch to soy for biofuels,” he said. “They’re going to redirect from food because that’s how commodities markets work. They’ll go to the highest bidder.”

At least for now, there are no immediate shortages because of sufficient grain stores. The critical issue is how to use and distribute what exists in ways that ensure food security.

“There are considerable amounts of grain we can use for other purposes than feeding animals or feeding cars,” said Pierre Marie Aubert, a senior research fellow with the European Agriculture Initiative at France’s Institute for Sustainable Development and International Relations. “The key question is whether policy makers want to address that question. They haven’t seemed willing to do so.”