TECH TALK | Newcastle University is developing alternatives to using coal in power

Coal loading and sorting equipment at Newcastle, NSW. Picture: Shutterstock.
Coal loading and sorting equipment at Newcastle, NSW. Picture: Shutterstock.

In September 1797 Lieutenant John Shortland went in the direction of Port Stephens on the NSW east coast searching for runaway convicts.

He stumbled across what he later described as "a very fine coal river" and (in one of those ultimate moments of praising your boss) he took it upon himself to name the estuary the Hunter River after Captain John Hunter, who was Governor of the British colony in New South Wales.

With Shortland's description of the deep-water port and the abundant coal in the area, it didn't take long before coal mining started and officially became the colony's first export.

As coal-diggers and timber-cutters started settling in the area, the new settlement was eventually named Newcastle after England's famous coal port.

By 1831 the first railway to carry export-coal was opened and today Newcastle is the largest coal exporting harbour in the world.

With such a history in coal, there is a huge amount of irony in the fact that Newcastle University is doing its absolute best to shut down the use of coal in power stations across the world.

Before I explain further on that, we should look at how a coal-fired power station produces power - the concept is relatively simple: Heat up water. Produce steam. Direct that steam past turbines to spin them.

By application of Faraday's Law of Induction, discovered in 1831, the moving turbines can induce voltage in an electrical circuit.

After construction, the major impact - financially and environmentally - is burning coal to heat up the water.

But what if we could heat up the water using a different method? Sure, burning gas or biomass are methods being used, but they still require the burning of 'stuff' so they aren't perfect solutions.

Newcastle Uni has invented thermal bricks using their patented Miscibility Gaps Alloy (MGA).

One argument against renewable power is that power is not produced when the sun isn't shining and the wind isn't blowing. Batteries are expensive and don't hold power forever and they require significant additional infrastructure. Storing heat in MGA is about to change all of that.

There are approximately 2425 coal-fired power plants in the world with an operating capacity of 2000 gigawatts (GW). The infrastructure is in place already with these power stations and they are already connected to the grid.

The magic of MGA is that it will allow heat to be generated when convenient (when the sun is shining and the wind is blowing) and capture that heat within the magical block. Then when power is needed, the heat can be released to produce power. Better still? The cost of MGA is one tenth the cost of equivalent lithium batteries.

The aim from Newcastle Uni is to bridge the gap between cheap and abundant renewable energy, which is often generated in peaks, and the ability to store and dispatch power at any time of the day.

Already the use of coal worldwide is decreasing, but the rate may not be fast enough with only a three per cent drop over the last year. MGA could accelerate this reduction.

The only bad news from this exciting development? Although Aussie ingenuity created this product, as so often happens with great Aussie ideas, commercialisation may rely on overseas partners. A Swiss company is the first to come on board to produce blocks for trial in a 55-megawatt (MW) demonstration plant.

Will MGA be the panacea the world needs to reduce our reliance on coal? Possibly, but it is heartening to know that Australian scientists are working towards innovative solutions.

Tell me if you have a better idea than MGA Thermal bricks at ask@techtalk.digital.

  • Mathew Dickerson is a technologist and futurist and the founder of several technology start-ups.