In news today, the Greens are calling for an end to federal funding for a proposed coal- and gas-fuelled power plant in Victoria’s Latrobe Valley. Others have suggested the plant provides a source of “transition” power: a stepping stone towards renewables.
So how much should we be investing in so-called transition fuels? Or should we be investing in renewables instead? And what will Australia’s electrical energy system look like in, say, 2050?
Well, it might consist of large-scale concentrating solar plants, rooftop photovoltaics (PV) on every building, wind and wave power, carbon capture and storage, or even nuclear.
Or perhaps more likely, we could be getting our energy from a combination of these technologies.
Much of what the 2050 energy landscape looks like depends on the decisions we make in the next decade as we move toward a low-carbon economy.
One of the hurdles to overcome is the need for so-called “baseload” power – power that will be available 24 hours a day, 365 days a year.
We need to build a new energy system without disrupting this constant and reliable supply of power we currently enjoy.
The road to renewables
Finding a stepping-stone to transition from coal to low-carbon technologies may be one of the biggest challenges of the next decade.
The ability to produce electricity 24 hours a day is perhaps the biggest advantage of coal-fired power. But this advantage is also a disadvantage.
It takes many hours (or even a day or two) to fire-up a coal-fired power station from cold. Because of this, coal-fired stations need customers that never switch off and a demand pattern that varies only gradually and in a predictable fashion. But this may not be the pattern of demand we have in the future.
So what does an increase in variable renewables mean for heavily-polluting coal-fired stations, even before we worry about the impact of a carbon price?
One potential pathway could involve large-scale introduction of PV and wind power. Given that environmental effects can cut the power produced by a PV array (clouds) or wind farm (no wind), fossil fuel-fired generators need to be on stand-by to pick up the slack.
Introducing such renewable generation methods will therefore increase the variability in demand on coal- and gas-fired generators.
And, in the face of more variable (but more sustainable) power generation methods, coal-fired power could become uncompetitive and might eventually be phased out.
Backup capacity would still be required and this would be met by gas-fired turbines. These can power-up and down very quickly.
But gas-fired power is more expensive (and possibly too expensive for aluminium smelting and other industries). The higher cost will certainly remove the incentives currently available for using off-peak power. Without those incentives, consumers will tend to use power during the peaks.
This would leave us with a dramatically different demand pattern of high-variability and low-overnight demand that doesn’t suit nuclear or coal.
The local angle
In Australia we have a set of technologies already well established – coal- and gas-fired power stations – with uptake of solar PV and wind power increasing rapidly but still only making a small impact in the overall generation.
There is also range of potential (but still untested) technologies such as large-scale solar thermal, carbon capture and storage (CCS) and, and at least in the Australian context, nuclear power.
Many suggest that CCS or nuclear will be our saviour, but these technologies will need to survive the transition.
The problem for yet-to-be-established technologies, especially nuclear and CCS, is they assume power consumption will continue to follow the baseload model.
This model shows that we consume power around the clock in large quantities, largely supported by energy-intensive industry that soaks up power that can’t be shut off; energy we don’t need in our homes and businesses as we sleep.
But a relatively new transition technology, know as coal gasification may change the pathway significantly.
The controversial new power plant proposed for the Latrobe Valley will showcase coal gasification. If approved, the facility – to be run by HRL electricity company – will use natural gas to dry and gasify brown coal, turning it into “syngas”.
Syngas is a combustible mixture of carbon monoxide and hydrogen that can then be burnt in a gas turbine to generate electricity.
This process of gasification enables cheap coal to be used in a fashion similar to normal natural gas, turning the power plant on and off quickly when required.
If HRL is successful, the Morwell plant could provide a lifeline to baseline-dependent industries (such as manufacturing and minerals processing), giving time for CCS and maybe even nuclear to be deployed.
While less carbon-intensive than older coal-fired power stations, the gasification process is still carbon-intensive, and will be exposed to carbon prices and environmental regulations. These factors will make it difficult to find funding for the gasification project.
If the HRL proposal fails, some other options may be available.
In the pipeline
Co-burning biomass (such as agricultural byproducts) in fossil fuel generators can reduce carbon emissions, but large sources of agricultural waste (such as sugar cane bagasse) are required.
This is an already established practice in Queensland, and could potentially be expanded to other states.
Hydrogen has also been suggested as a transition fuel. It can be generated from natural gas or coal and used in fuel cells to power vehicles or to generate electricity.
But the wind seems to have gone from the sails of the hydrogen economy with electric vehicle technology dominating in recent years.
Accurate predictions of how the energy market will respond to a carbon price or increased variable renewables is difficult at best. It’s even harder to predict the electricity price at which large industrial processes – such as aluminium smelting – become unviable.
The best strategy we have is to not exclude any viable energy technologies, to keep an open mind and to keep pursuing the many options on the table.
We also need to watch how market forces and regulatory frameworks play out over the next decade.
Everything depends on everything else but one thing’s clear: our energy future is uncertain.
Join the conversation
Comments (12)
Alex Cannara
(logged in via Facebook)
The unfortunate reality is that our path was clear in 1962...
http://tinyurl.com/6xgpkfa
and, if we'd followed it, we'd have had 700GW of clean, base-load nuclear power in the US, plus growing local solar on existing structures. No need for subsidized, land/sea-hungry wind/wave/solar 'farms'., all of which waste power in transmission forever and degrade the environment.
Fortunately, China & others are moving ahead, 49 years late, with what we (ORNL) achieved in the 1960s regarding safe nuclear…
show full comment
Michael Swifte
writer (logged in via email @yahoo.com.au)
Good general coverage of the issues. Good to see baseload getting the attention it deserves.
I was very disappointed to see solar thermal lumped in with carbon capture and storage! Solar thermal is commercialised, and if state and federal governments weren't so in love with gas company $$ we would be seeing plans like those prepared by Beyond Zero Emissions put into action.
Transitional power from gas is the worst thing we could do with carbon tax revenue. We would merely create a new power base from whom we would have to wrest the right to develop our renewable energy sector.
Gas will run out but the sun will always shine!
Zvyozdochka
(logged in via Twitter)
The ‘baseload’ concept of electricity provision is broken.
Electricity grids currently look like this;
Supply = ‘baseload’ + variable peaking (gas?) = Demand
Big central nuclear power plants and big coal plants are the reason this concept exists. No-one had bothered to think differently about it and the vested interests don’t want that model changed either.
In a renewable world the electricity grid needs to look like this;
Supply = variable wind + variable solar (w/storage)+ top-up/backup (gas…
show full comment
Will
(logged in via Twitter)
The baseload concept is not broken - there is always going to be a minimum level of demand for power on any power grid. This can come from different demand sources at different times of the day - baseload demand is merely an aggregate. If transport becomes more electrified, night-time charging of EVs may replace the demand from industry for instance.
Using reliable sources of power to supply this baseload is a common-sense idea.
The concept of replacing a large centralised generator with a whole…
show full comment
Zvyozdochka
(logged in via Twitter)
"It also requires supply overbuilds in the case of renewables if you want to get rid of 'top-up' power sources like OCGTs as you want"
Not really. Just a "booster" gas burner in a CSP w/storage plant. Cheap.
The main problem is the contract for gas; if you approach the suppliers saying "we plan to use as little as possible", strangely enough you get a fairly odd response. Which leads me to;
"There is no conspiracy led by faceless corporate overlords that stroke cats and smoke Cuban cigars."
Really? Those people are the owners of the existing model (including gas supply) and they don't want it modified.
Will
(logged in via Twitter)
CSP w/ storage and gas supplement is fine for balancing out your solar supply, but you'll still need some sort of backup for wind - you could do this with the CSP plant ideally but you may need a fair bit of power, so the gas supply issue becomes apparent. You would need a long pipeline or a significant storage tank on site if a molten salt CSP w/ gas backup plant is situated in a place like the Mallee in Victoria, away from the gas distribution network. Supply contracts are a simple business matter…
show full comment
Zvyozdochka
(logged in via Twitter)
On our work, CSP w/storage is likely a lower LCoE now in Australia than nuclear or very very shortly.
Will
(logged in via Twitter)
Three questions on that: Who, how and when?
stephen prowse
(logged in via Twitter)
An interesting discussion of such an important and issue. With such a complex mixture of market and regulatory forces, new technology, vested interests and ideology, uncertainty is no surprise. With forecasts of only 2.8% of global energy coming from renewable sources by 2030 as seen in the above article, it is easy to be rather pessimistic. Is it too hard for Governments to put in place a regulatory framework that facilitates the adoption of sustainable energy sources, removes tax payer subsidisation of energy providers be they gas, coal or renewable, without a large adverse impact on the community?
John Harland
bicycle technician (logged in via email @gmail.com)
Storage technologies are developing fairly rapidly.
It would be useful to assess how much of baseload demand is generated through incentives to use "off-peak" electricity. If we could shift a significant proportion of this demand, we might find storage to be economical sooner than we imagine.
We should be skeptical of changeover from coal to gas as an outright improvement. Methane has a global warming potential an order of magnitude higher than CO2 (at the 100-year horizon).
Many processes for obtaining methane involve considerable wastage. Notably coalseam gas. The effect of this should be factored into any proposed substitution of one for the other.
wilma western
(logged in via email @bigpond.com)
I live in Gippsland not far from the proposed site of the HRL plant. I rely mainly on newspapers and some internet info and this is the first time I have read how the HRL plant is supposed to function. All the info I have read so far is that HRL emissions would be equivalent of a modern black coal generator, that the first Govt subsidies were announced during the Kennett govt, that the Feds got into the act under Howard and that despite all the promises of Govt money, Chinese involvement etc ,financiers are still reluctant to commit even to the scaled -down present proposal.
And what is CSP? Good to read that 2 high profile firms are doing smart grid investigations.
CHAGANTI BHASKAR
(logged in via Twitter)
WORLDS CHEAPEST ELECTRICITY cost per each MW 3 million US$ is for construction, machinery etc and generation cost just 10 Indian Paisa or 1/3 a cent per KWH or unit
RAW MATERIAL IS FREE AND NO TRANSPORTATION CHARGES
SMALL GRID IS SMART GRID IS MY CONCEPT FOR TRANSMISSION TOO
METHOD:
FULL TEXT
Renewable energy is considered to be “environmentally” clean – meaning it is typically non-polluting example the application is water running in man made structures is my idea…
show full comment