Solar Farmland?

Solar is quickly becoming a major energy source. The market for solar energy has grown massively over the last few years and is still expected to grow by 15.4% CAGR in the US until 2030.

Solar is quickly becoming a major energy source. The market for solar energy has grown massively over the last few years and is still expected to grow by 15.4% CAGR in the US until 2030.

Source: Grand View Research

The West's adoption of solar energy is actually dwarfed by the global growth of solar energy, with China leading the charge, as it is responsible for more solar power project pipelines than the rest of the world combined.

China has been ramping up its renewable energy capacity year on year, installing more solar power between 2023 and 2024 than the previous three years combined, and more than the total global capacity installed in 2023.

This has put the Asian giant on track to achieve an installed wind and solar capacity of 1,200 GW by the end of the year, putting it six years ahead of the government goal.

Source: Energy Wind Down Media

This has led important publications like The Economist to literally call it a new age. We explored what new technology will make it a reality in “The Solar Age – A Bright Future To Mankind”.

Source: The Economist

Progress in semiconductor manufacturing and a growing economy of scale in the production of solar panels has led to a steady decline in photovoltaic costs, which have become 30x cheaper since 1990. As a result, photovoltaic technology is now dominating the solar industry.

Source: EIA

However, solar energy is starting to meet an issue. This is because solar is relatively low in energy density when looking at land usage.

In fact, it is one of the least efficient energy sources regarding land usage, with only equally carbon-neutral wind, hydropower, and biomass scoring worse.

Source: Wouter Beel Gravendeel

This leads to situations where farmland or natural habitats get covered with solar panels for utility-scale solar farms. So, while this reduces carbon emissions, it comes with many unwanted side effects, from the destruction of natural habitats to the risk of erosion, especially in mountainous areas.

For example, in the Fujian province of China, you can see the entirety of these hills covered in solar panels.

Source: The Atlantic

Shortage Of Arable Land

This is a growing problem, as we are already losing a lot of arable land every year, as much as 100 million hectares yearly. The largest factor in these losses is not solar farms but erosion, desertification, urbanization, poor farming practices, etc.

However, this does not mean that the solution to one problem (carbon emissions) should become a problem for another major issue (arable land losses).

Some solutions are obvious, like utilizing rooftops, especially industrial buildings, but also residential ones. Using desert lands can be another option, but these are also fragile ecosystems, and removing dust consumes a lot of locally rare water resources.

These can be part of the solution, but for solar to replace fossil fuels entirely, it will need to keep growing at a double-digit rate for decades. And land usage will become an issue.

So, the best solution would be to mix agricultural and power production, using a method called agrivoltaics (agriculture + photovoltaics).

Source: Dezeen

Farm Buildings

The simplest way to integrate solar power into farms would be first to leverage farm buildings' remarkably large rooftop surfaces. From hay storage to garages and barns, many farm buildings have tall, large, uniform rooftops that are perfect for installing solar panels.

Source: X/Twitter

While maybe not technically agrivoltaics, this is a first step that should have been taken yesterday.

This should also be a key component in switching farming away from fossil fuels through a few complementary initiatives that will anyway be required for other forms of agrivoltaics:

Farming Power

The main issue with mixing farming and solar power generation is that in theory, both are competing for the same resource: sunlight.

Sunlight is after all the energy source of the plants being farmed, be it crops or the grass in a pasture. In a way, farming is already harvesting solar energy, although in the form of edible biomass instead of electricity.

So at first glance, it might seem like a pipe dream. But when digging deeper, it is more complex than just plants needing the sun taken away by the solar panels.

Photoinhibition

While it is a convenient simplification, plant photosynthesis can be explained as a simple scheme like

“Input light, water, & CO2 -> output sugars”, the process is actually a very complex one.

Something that happens very often in real open-field conditions is a phenomenon called photoinhibition.

This is when the sunlight is too intense for the plant to absorb, causing the production of damaging radical oxidant molecules. This damages the photosynthetic ability of the plant and reduces crop yields.

Source: Frontiers In Plant Science

This means that on most summer days, especially in southern