Solar panels in a field
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New hybrid agriculture model brings food and energy benefits 

5 March 2024

Combining traditional agricultural farming land with renewable energy technologies reap potential benefits.

Agriculture and energy have been essential to humanity for at least 10,000 years. But we’re now shifting to “farming” them together. This has given rise to a brand new word - “Agriphotovoltaics”, which is the blending of agriculture and solar photovoltaic panels on the same land. But sharing can be tricky. There has to be a balance.

On one ideological extreme, the protestors at the “Rally Against Reckless Renewables” (held outside Federal Parliament House in February 2024) were fear-mongering. They claimed that we couldn’t have both renewables and agriculture.

But agriculture is already under threat from bigger problems than renewables. Farmers have struggled with major changes in rainfall, temperatures and extreme weather events (caused by climate change), plus the devastating effects of fires and floods.

Consider also that current agriculture is responsible for about a quarter of all greenhouse emissions (mostly livestock farming and synthetic fertilisers).

This is partly why the concept of dual use of land (food and energy) was proposed back in 2011. The renewable electricity could offset emissions, increase income and perhaps improve the agricultural yield.

However, there are so many factors to consider in successfully introducing agriphotovoltaics.

To begin with, which plants (potatoes, alfalfa, corn) or animals (sheep, cattle... etc) should be used?

One study looked at the crop, alfalfa, grown for two years, under pivoting solar panels that could be angled to be square-on to the Sun. This pivoting configuration is more expensive, but can increase electricity yield by 40%. They balanced the orientation of the solar panels against the crop needs – but crops don’t need 100% of the Sun’s radiation, all the time. For example, some stages of a plant’s lifecycle (e.g. end of life, grain filling) need less light than other stages. The electrical output dropped by 15% from the maximum, but the yield of alfalfa increased by 10%!

We now have data from France, Japan, Germany and other countries.

It’s clear that agriphotovoltaics, like agriculture, is complicated. For example, we have to consider properties of the soil (thick, thin, sandy, volcanic...etc), ratio of productive to non-productive land (e.g. river flats, or sandy deserts), specific energy infrastructure (solar photovoltaic, wind turbines, transmission towers... etc), local weather (windy or still, sunny or cloudy, rainy or dry...etc) and many more. As an unexpected upside, solar panels protect against hail and heat waves, night frosts and more.

About half of France is farmland (very different from Australia). French farmers can make 10-100 times more Euros/hectare by leasing their land to a renewable energy company, than from farming. So the French Government stepped in and passed the decree “On Accelerating the Production of Renewable Energies”. This was to ensure that all renewable electricity projects provide some kind of agricultural benefit – improving yields, protecting crops...etc.

Other governments have recognised the need for a national policy. Germany allows a drop in agricultural yield of 33% from dual-use agriphotovoltaic farms. Japan allows only a 20% loss.

In Western NSW, Tony Inder has 1700 merino sheep grazing under hundreds of hectares of solar panels. He has seen improvement in both the quality of the grass, and therefore the wool.

Farmers can generate significant income from electricity generation and transmission. In NSW and Victoria, they get $200,000 per kilometre. Solar farms can generate $1,500/hectare/year, while wind turbines pay around $40,000/turbine/year.

This new hybrid agriculture can bring benefits for all – with good national planning and regulation.

Dr Karl Kruszelnicki
Julius Sumner Miller Fellow