While PV, wind and batteries have changed our energy mix forever and for the better, the steam-driven turbine, long associated with fossil fuel-fired power, is on the cusp of its own renewable revolution.
Steam turbine driven power plants have been historically the backbone of the electrical system due to their technical capabilities, supporting the grid and connecting inertia to the system.
Concentrated solar thermal technology promises the same benefits as a turbine-driven power plant but is 100% renewable. This technology could be the next jobs boom for regional Australia, offering a genuine transition for fossil fuel workers to work in similar roles in the renewables industry.
Concentrated solar thermal is the ‘other’ solar power that complements its more widely-used cousin, solar PV. While solar PV turns photons into electrons, solar thermal captures the sun’s heat.
These plants focus the sun’s rays with mirrors to heat a fluid and store the heat, typically in molten salt tanks. The heat is used to produce steam and to drive a steam turbine to generate electricity.
As the heat can be stored, it can generate dispatchable electricity 24/7 on-demand, ramping up or down according to the market or providing power overnight.
The steam and the heat generated can be used for industrial processes increasing the efficiency of the plant. This technology provides clean dispatchable power alongside the system-strength benefits of electricity generated from a steam-driven turbine.
Around 100 utility-scale solar thermal plants are in operation globally. China is building 28 of these plants and Spain’s solar thermal plants have an installed capacity of more than 2,300 megawatts. Dubai has commissioned a 700MW solar thermal project with 15 hours of storage.
Despite Australia’s high rates of solar radiation and availability of land, we have no utility-scale CSP plants in operation. This is a missed opportunity for the regions where coal and gas power plants currently operate, and where CSP plants would be located.
Coal plants employ somewhere between 200 and 300 people and prop up regional towns and cities with high-paying, high-skill positions. They are full-time specialised roles such as boilermakers, pipe-fitters, electricians, systems engineers and managers – people not readily supplied by labour hire or contractors.
As coal and gas fired plants are retired, regional Australia could see many of these specialist energy jobs retained by building CSP plants, whereas those jobs and skills are not needed in wind and solar PV projects that will retain a negligible number of local jobs as they are operated from control centers centralised in big cities
In the Reserve Bank of Australia’s Bulletin – March 2020, ‘Renewable Energy Investment in Australia’, the bank found that local content accounted for just 25-40 per cent of total costs of wind and solar PV projects, mainly in “engineering, construction and installation services,” i.e., not in ongoing jobs such as operations and maintenance and not in the hardware supply chains that sustain renewables projects.
The Australian Solar Thermal Energy Industry Association (AUSTELA) uses a benchmark 100MW CSP project to demonstrate the employment expected from a CSP plant built in regional Australia.
In the construction phase of 42 months, a base of 800 workers is employed. Over the peak construction period of 12 months, 1700 workers are typically employed, and the ongoing operation and maintenance stage employs around 200 workers.
The Spanish Renewable Energies Association (APPA) reports that operations and maintenance activities at their CSP plants account for around 1.4 direct jobs per MW.
Regional Australia could enjoy a jobs boom where CSP plants are built as zero-emission replacements for coal. If Australia built the same level of CSP infrastructure as Spain, 4600 direct ongoing CSP jobs would be created in the regions, and a total of 39,100 jobs would be created during the peak construction phase.
The CSIRO Renewable Energy Storage Roadmap estimates that in 2050, Australia’s power grids (NEM and WA) will require 150GWh of solar thermal storage – or a capacity of 10GW assuming an average of 15 hours of storage – which translates to 20,000 potential ongoing jobs.
CSP plants can be a key player in the generation mix that is necessary in Australia to have dispatchable renewable energy and, at the same time, supporting regional workforce and expertise that otherwise will be lost.
The employment benefits of CSP continue beyond the plant. As the Australian industry decarbonises, CSP attracts industries around it that need green power as well as green heat. Industrial heat is a significant challenge, according to the Australian Renewable Energy Agency, accounting for 44 per cent of the nation’s end use energy, of which 52 per cent is process heat predominantly provided by gas and coal.
CSP-derived heat has the potential to create more jobs in the regions, in heat-reliant industries such as food processing, fertiliser production and the pulp and paper industry. The renewable heat + power combination is also the requisite for making green liquid fuels such as Green Methanol and renewable hydrogen.
The key to CSP is that it uses a steam turbine to generate power and can store its zero-emissions heat. This is a perfect renewable energy technology for Australia but it also requires the expertise of the trades and professionals that are currently running turbine-driven power plants. Those workforces live in regional Australia, where the coal and gas plants are.
CSP can be a crucial brick to build the renewable era in Australia , providing an economic lifeline to many regional Australian towns, by generating reliable clean power and heat, helping to decarbonise industry and sustaining high-skilled jobs in the energy sector.
Víctor J. Marín is director of the Australian Solar Thermal Industry Association (AUSTELA)
