‘Ultra-low-cost solar’ key to net zero
If all goes to plan over the next couple of years, Swanborn will build a factory in Queensland to make 1 gigawatt of powerfoil each year: enough to cover the grass playing surface of the Melbourne Cricket Ground about 500 times.
Swanborn says a Queensland factory of that size should be capable of producing powerfoil at a unit cost between 5¢ and 7¢ per watt of energy generated; well below the industry standard for crystalline silicon solar panels, of between 19¢ and 21¢ per watt.
The goal of making low-cost solar panels has taken on extra urgency over the past year as the decade-long decline in the cost of solar panels suddenly reversed, sparking fears the cost of decarbonising the global economy may prove higher than previously expected.
Energy research company Wood Mackenzie reported that prices for solar panel in the United States rose by 18 per cent in 2021 because of supply chain disruptions, soaring energy costs and rising prices for the metals that go into conventional panels, particularly poly silicon.
Similar price rises were experienced in Australia, where installation of solar generation in the first three months of this year was 28 per cent lower than the same time last year; ending five consecutive years of rapid growth in installed solar capacity.
Wood Mackenzie reported the US industry installed 24 per cent less solar capacity in the first three months of this year compared to the same period in 2021.
The Goldilocks point
Reducing the amount of poly silicon that goes into mainstream solar panels is now a key focus among those working on the challenge of low-cost solar. AP
Rombout Swanborn at his solar factory in Arnhem, Netherlands.
Sabine van Wechem
The surging cost of solar panels came in the same year the Australian government nominated “ultra-low-cost solar” as one of six “priority technologies” that would need to be developed for Australia to achieve net zero emissions by 2050.
Reducing the amount of poly silicon that goes into mainstream solar panels is now a key focus among those working on the challenge of low-cost solar.
It may require a compromise; reducing the size of the silicon wafers that work as semiconductors in solar panels reduces cost, but it also reduces the amount of sunlight the wafers can convert into power.
Researchers from the Massachusetts Institute of Technology reported in 2019 that there was a Goldilocks point to be found when wafer thickness was reduced from the typical 160 micrometres to 50 micrometres, with that change reducing the overall cost by US7¢ per watt.
Others are seeking to bypass silicon altogether, with researchers at the CSIRO and the Australian National University making encouraging progress on cheap, flexible, high efficiency solar panels made with a material called perovskite.
Swanborn’s powerfoil does not use poly silicon wafers; it’s photovoltaic film is made with silane, an industrial gas that is a compound of silicon and hydrogen.
“These layers are typically a hundred times thinner than the crystalline silicon materials, and that’s one of the big advantages – you need much less of the expensive material than you need in glass panels,” he says.
Powerfoil’s thinner photovoltaic layer converts less sunlight into energy than conventional panels.
When Swanborn acquired the …….