If Biofuel Land Became Solar Farms, Could It Power the World’s Electric Vehicles?

Electric vehicles are now widely seen as the future of low-carbon transport, but two decades ago, biofuels held that promise. The idea was simple and compelling: instead of extracting and burning fossil fuels, grow crops such as sugarcane or maize and convert them into transport fuels. Yet, even as electric mobility accelerates, global biofuel production continues to rise. This raises a fundamental question about land, energy efficiency, and climate strategy: are we using scarce land in the smartest possible way?

Why biofuels once looked like the future of transport

In the early 2000s, biofuels were promoted as a climate-friendly alternative to petrol and diesel. Major producers such as Brazil (sugarcane ethanol), the United States and the European Union (corn ethanol), and countries like Indonesia (palm oil biodiesel) built large biofuel industries.

Today, biofuels account for roughly 4% of global transport energy. While this displaces some oil, the climate benefits are often smaller than assumed once emissions from cultivation, fertilisers, processing, and land-use change are considered. In some cases, the net carbon savings over fossil fuels are modest.

The hidden cost: land is not climate-neutral

The biggest challenge with biofuels lies not only in emissions, but in land use. Agricultural land is a finite and valuable resource. If it were not used for crops, it could be rewilded or reforested, absorbing carbon from the atmosphere. This “opportunity cost” is often overlooked in climate debates.

A recent analysis by Cerulogy estimates that biofuels occupy about 61 million hectares globally. When land used indirectly for animal feed is excluded, around 32 million hectares are devoted directly to biofuel crops. This article adopts that lower figure deliberately, making the comparison conservative. Even so, 32 million hectares is roughly the size of Germany or Italy.

What if that land were used for solar power instead?

The energy comparison is striking. If solar panels were installed on 32 million hectares, they could generate roughly 32,000 terawatt-hours (TWh) of electricity each year. That is about 23 times more energy than the world currently gets from all liquid biofuels combined.

To put this in perspective, total global electricity generation in 2024 was around 31,000 TWh. In other words, solar panels on existing biofuel land could theoretically produce enough electricity to meet current global demand.

This dramatic difference stems from basic physics. Plants convert less than 1% of incoming sunlight into usable biomass through photosynthesis, and further losses occur when crops are processed into liquid fuels. Solar panels, by contrast, routinely convert 15–20% of sunlight into electricity, with advanced designs reaching even higher efficiencies.

Can solar electricity decarbonise transport?

At first glance, comparing biofuels (used in transport) with solar power (used for electricity) may seem misleading. But this distinction is dissolving as electric vehicles become mainstream.

If road transport were fully electrified, global cars and trucks would require an estimated 7,000 TWh of electricity per year — roughly 3,500 TWh for cars and a similar amount for trucks. That is less than one-quarter of the 32,000 TWh that solar panels could generate on current biofuel land.

In simple terms, the same land that now meets about 3–4% of transport energy demand via biofuels could, if used for solar, power all global road transport — with land still left over.

What this comparison does — and does not — argue for

This analysis is not a proposal to replace all biofuel crops with solar panels. Land has many competing uses: food production, some biofuels (especially for aviation), biodiversity restoration, and rural livelihoods. Energy systems also require storage, grids, and complementary technologies to ensure reliability.

What the comparison does offer is perspective. Land use always comes with trade-offs, yet discussions often scrutinise the footprint of solar or wind farms while ignoring the vast land already committed to biofuels that deliver relatively little decarbonisation.

Rethinking land use in a low-carbon future

As electric vehicles scale up and renewable power becomes cheaper, the opportunity cost of biofuel land will only grow. Using land more efficiently could unlock far greater climate benefits, while freeing space for food security or ecological restoration.

The core question is not whether biofuels or solar are inherently “good” or “bad”, but how societies choose to allocate land in a carbon-constrained world. When viewed through that lens, solar-powered electrified transport highlights just how much more climate value could be extracted from the same hectare of land — if decisions are guided by efficiency rather than legacy assumptions.