Imagine you’re halfway through your annual wheat harvest when a global crisis sends diesel and fertiliser prices soaring. All at once, your costs surge and your slender profit margin shrinks.
Authors
- Md Alamgir Hossain
Senior Lecturer, Electrical and Electronic Engineering, University of Southern Queensland
- Shahbaz Mushtaq
Director of the Centre for Applied Climate Sciences, University of Southern Queensland
Are there alternatives? Increasingly, the answer is yes. Putting solar on the shed roof or an unproductive field could help keep the farm running.
In August, the federal government announced it would lift the cap on the long-running small-scale solar subsidy from 100 kilowatts to one megawatt – a size well suited to larger energy users, such as big farms.
If this plan comes into effect, it should reduce installation costs by about 20% , saving an estimated A$68,000 on the installation of a 250 kW system.
This could make larger solar systems more appealing for more farmers, reducing electricity costs and boosting energy self-reliance in the bush. It’s not yet possible to be fully self-reliant, as electric tractors and heavy machinery are still emerging . Anti-renewable sentiment in some communities could also be a challenge .
How far can farms go?
If farmers have the space and funds to build a large solar array, this may make sense as a first measure. The ability to produce low-cost electricity opens up many more options – especially if paired with energy storage such as batteries, so power can be stored and used later.
Some farms are shifting to hybrid models, where solar and batteries are integrated with farm equipment and a backup generator to form the farm’s own microgrid .
What about fuel? Right now, Australian farms are highly reliant on diesel. This energy-dense fuel supplies about 84% of the energy used on Australian farms.
Diesel powers harvesters and tractors. But it also runs water pumps and power generators. Over time, farmers can replace broken pumps with electric options and run their operations on solar power.
Much more can be done. This year, AgriFutures Australia laid out a roadmap for farming and other primary producers to shift from diesel to electric options.
Are farms actually doing this?
These technologies are already in use.
New South Wales almond operation Cadell Orchards has long been off-grid. Until recently, its irrigation pumps were powered by diesel generators. But diesel was getting too expensive and a grid connection wasn’t viable. As Australian Farming Services CEO David Armstrong said :
we couldn’t stay on generators forever … it just wasn’t feasible [and] the variability of costs is too great
Instead, the agribusiness installed a microgrid with over 8,000 solar panels and a battery. The goal is to produce over 85% of its own power.
To avoid the upfront cost, the business didn’t buy the whole system. Instead, an energy company owns and maintains it, while the orchard buys the power.
Some farmers have taken up ” agrivoltaics “, which means combining farming and solar panels. Fields can carry more sheep and produce more and better wool, according to some farmers . This is because solar arrays provide shade and can help the ground retain moisture longer.
Tractors, harvesters and speed bumps
Small electric tractors are becoming available for smaller-scale jobs .
But large battery-powered tractors and harvesters aren’t ready for prime time yet, as diesel packs more energy by weight than today’s batteries by a wide margin .
There are other challenges too. Large electric machines would likely have to recharge during the working day , meaning charging infrastructure might have to be located near fields. Farmers often put in long hours to bring the crop in. Stopping for long recharges could interfere with time-sensitive crop harvesting.
The AgriFutures roadmap predicts stationary equipment such as pumps will electrify first, while liquid fuels will remain important longer.
Solar paired with batteries can keep a farm running overnight or during cloudy periods. But if dark, cloudy days drag on, it may be time to bring out the generator.
For some businesses, a battery may not stack up financially .
Even free sunshine can hit a roadblock. After Queensland cotton farmer Ian Brimblecombe installed a large solar system, he began saving about $60,000 a year. But power network rules restricted how much electricity he could export or move between pump stations.
It’s not all or nothing
Over time, more farms will produce more of their own energy. But there’s no silver bullet, and the shift will take place in fits and starts.
Some farmers may find it viable to produce their own biodiesel from oils or waste fats to keep existing machinery working.
For farmers to get the most out of clean energy, they will need dependable equipment, affordable finance, local technicians and guidance from people they trust. These aren’t always easy to access .
Some rural communities are sceptical about large-scale renewable projects and new transmission lines, often due to a perceived city-country divide . Campaigns against new solar, wind or transmission projects often focus on the impact on the landscape and distrust of far-off authorities. False claims are common . This may slow the shift towards energy self-reliance.
Over time, we may see this resistance become more nuanced. Some farmers may keep opposing large-scale projects, while moving to install their own systems.
New incentives may sweeten the deal too. We’re unlikely to see the farm diesel tank disappear any time soon. But we are likely to see many more shed rooftops covered in panels – and new ways to make use of clean, cheap power from the sun.
