In the South Australian desert, this solar-powered facility grows tomatoes for the nation. Driving across the wide saltbush plains towards Port Augusta, north of Adelaide, the first thing a visitor notices on the horizon is the sky-piercing solar tower of Sundrop Farms. Only when you get close do you see the 24,000 mirrors arrayed at its base, each of them beaming the sun’s rays to the tower’s tip, 127m above the ground. The thermal energy harnessed here powers 20ha of adjoining glasshouses, which in turn produce about 350 tonnes of tomatoes each week.
Welcome to farming of the future: a hi-tech, capital-intensive system growing food sustainably and cleanly for the masses – all located in rocky, arid country where southeast Australia’s cropping zones meet the Outback and annual rainfall is less than 250mm. “If you can farm successfully here, you can farm almost anywhere in the world,” says CEO Philipp Saumweber. “I’m no eco-warrior but I wanted to create a new business model for farming, based on a concept of doing more with less and growing in the most sustainable or restorative manner. This is what we have achieved.”
Sundrop Farms is now a $175 million, highly productive “farm” producing 10-15 per cent of Australia’s truss tomatoes. It runs almost entirely on solar thermal power, courtesy of the 15ha array of mirrors that feeds the tower with heat energy, rather than using the more common photovoltaic light-converting panels. The energy is used to heat seawater in vast boilers, generating electricity from the resulting steam and thermal heating for the hothouses. The steam-generated power drives a large desalination plant, turning constantly circulating seawater from the nearby Spencer Gulf into fresh water. In the glasshouses, 750,000 tomato plants dangle their roots into hydroponic pipes.
The farm employs 150 workers from Port Augusta and nearby Port Pirie, including many long-term unemployed or those displaced by the mining downturn. The intensity of Port Augusta’s light and the controlled growing environment mean tomatoes can be picked just 10 weeks after each seedling is embedded in its hydroponic pipe. New seedlings are planted between mature vines, giving Sundrop a unique production cycle spanning 50 weeks a year – crucial for supplying Coles supermarkets with up to 25,000 tonnes of tomatoes each year.
“It sounds like high-cost farming but because of our scale and low running costs we can actually grow tomatoes incredibly competitively,” Saumweber says. “You have to put in a lot more capital up-front to build it but we don’t have to buy water, electricity, fuel or insecticides, our land is cheap and our annual costs of running a big horticultural operation are very low.”
“This is the future,” says Saumweber. “Just as the green revolution of the’70s gave us bigger tractors, more seed varieties and better irrigation, I think the next giant leap forward in food production will be the sustainable intensification of farming – doing more with less inputs but on a bigger scale and with greater efficiency.
Source: Sue Neales (The Weekend Australian)