Pub: Sydney Morning Herald
Section: News and Features
Clean energy alternatives to allay Big Coal’s flood of tears
JOIN THE DEBATE
To blame Bob Brown is to shoot the messenger. As we ache for Queensland’s losses and rightly look to recovery, we must also heed the cataclysm’s larger lesson.
It will be tempting for governments to shore up the coal industry, a hard-hit Queensland business. And easy for the rest of us to habituate to repetitive catastrophe as though it were simply the natural order.
But although causality is ultimately unknowable, the near certainty is that these cataclysms are, in both frequency and magnitude, anthropogenic. As Gaia’s warning they offer the profoundest reason for not Band-aiding the coalmines but actively embracing change.
Even before the flood, getting Big Coal to clean up its act was like getting a child to clean up its bedroom. There are three typical stages: initial resistance, bluster and promises then, when that fails, tears and self-pity. But when bedtime comes, the room is still a cesspit.
Big Coal’s resistance manifested in the denialist energy policies it drafted for the Howard government. Then came “Coal 21”, a 21-company voluntary levy promising $1 billion of “clean coal” projects but in five years spent barely a tenth as much, and that on the easy, paper end of the game. That was the bluster.
Now, after the flood, it’s tears and self-pity, making governments reluctant to impose, for instance, the carbon tax we all know we need. And at once clean coal – if it were possible – is further away than ever.
CCS (carbon capture and sequestration) is the G8 countries’ official solution. The theory is simple. Separate the carbon dioxide from the smoke, pressurise it into liquid form and inject it underground – often into last-legs oil wells where it is used to exude the crude. Thus do the dinosaur technologies hold hands and comfort each other as their sun sets.
But although CCS projects supposedly number 275, only four, concedes NewGenCoal (Coal 21 rebadged), operate: two in Norway, one straddling the Canada-US border and one beneath the Algerian Sahara. None attaches to a power station.
Why so few? It’s partly money. Retrofitting a power plant for CCS costs about $1.5 billion, and running carbon capture can consume 40 per cent of a station’s power output, so no one will move without a firm carbon price. But there’s also efficacy. How much carbon dioxide can you keep pressurised, safely, underground, and for how long? Many insist that the technology is safe and workable. But the oldest guinea pig project dates from 1996, so there’s a way to go in the proof department. Keeping nuclear waste locked down for 100,000 years is daunting enough, but carbon dioxide is forever.
China – the world’s biggest carbon dioxide emitter and set to triple its coal-fired capacity by 2030 – is building the first emissions-free, carbon-capture, coal-fired power station in Tianjin by 2015.
But why take such trouble to make carbon dioxide the problem when it could be part of the solution?
Global energy demand is about 13 terawatts (a terawatt is a trillion watts; a watt is a joule per second). Eighty per cent of this is fossil-derived. For civilisation to survive, a California Institute of Technology chemist, Nathan Lewis, calculates, 90 per cent must be carbon-free by 2050. To do it with nuclear power would mean building a reactor every two days for the next four decades.
Yet if we don’t do it, melting ice caps will be the least of our worries. Melting the permafrost, with its vast reserves of carbon dioxide and methane, will turn global warming, and its weather extremes, exponential.
Luckily, there are other ways. Carbon farming is one. Algae is another. A Victorian company, MBD Energy, has contracted with Australia’s three largest greenhouse emitters (Eraring Energy NSW, Loy Yang in Victoria and Tarong in Queensland) to pilot a bio-CCS project using algae. MBD calculates with 1500 hectares it could recycle 50 to 100 per cent of each station’s carbon emissions.
MBD’s system ducts carbon dioxide through waste water (sewage is best) for absorption by select micro-algae that double in mass every 24 hours, speeding nature’s oil production process a zillion times. The algae are then crushed to form algal oil (used as biofuel and in plastics) and algal meal (used as fertiliser and low-methane, drought-proof stock feed).
This effectively recycles carbon instead of digging it up anew. But clearly the best way to sequester carbon is to leave it unburnt, underground, and find other fuels.
The sun pours 120,000 terawatts of energy onto Earth; 10,000 times what we need. With solar technology only 10 per cent efficient, calculates Lewis (and efficiencies now are often 15 per cent or higher), the entire energy needs of the US could be generated from a 400-kilometre square of Earth’s crust.
Photosynthesis might be considered a form of solar technology. It’s just a shame that, although it absorbs carbon dioxide, we can’t release the energy it stores – in trees, coal or oil – without also releasing their carbon.
So artificial photosynthesis, the holy grail of renewables, focuses not on absorbing carbon dioxide but on producing clean fuel directly from the sun. Using photons to split water, it produces only oxygen and hydrogen, for use either as a fuel (waste product, water) or in a fuel cell.
The biggest remaining problem is that most such systems require rare and expensive catalysts, such as the silver phosphate required by a new Japanese system with an astonishing 90 per cent efficiency. To be scaleable, a cheaper, more common catalyst must be found.
But giving up because the technology is imperfect is the kind of thinking that would have had you investing in horses, not cars, this time last century. Australia could easily support itself on renewables alone. Melbourne University’s Zero Carbon Australia plan insists that, using only wind, solar, biomass and hydro, we could be carbon-free by 2020.
Crazy not to try. Don’t blame Bob Brown. This is Gaia’s lesson. Children, learn your cataclysm!
DRAWING: EDD ARAGON