Hewson’s enthusiasm for solar towers is welcome, but wild claims are not

RenewEconomy

John Hewson has been an amazing campaigner for renewable energy and strong climate action in this country – challenging politicians, bankers and industry to take climate action seriously and embrace the need for a dramatic energy transition.

His proposal for a major solar tower and storage power plant in Port Augusta is also welcome, and he is right to suggest that one day Australia’s energy system will not be powered by fossil fuels, but by a mixture of renewable energy such as wind, solar and hydro, with a major contribution from solar tower and storage.

Welcome too, is the apparent bi-partisan support Hewson managed to gather at the launch of the Solastor project in Adelaide. Environment minister Greg Hunt was there, so too was opposition spokesman Mark Butler, as were South Australian premier Jay Weatherill and climate change minister Ian Hunter.

All, apparently, were captured by the glowing promise of the Solastor technology – the world’s cheaper 24/7 solar power, eventually at 4c/kWh, cheaper than solar PV, and a plant ready to be built in Port Augusta by 2018, with no subsidies needed, not even an off take agreement.

But there is one major problem. It all sounds too good to be true. The claims and projections made by the SolaStor team stretch the point of credibility. Is it really possible to build a 170MW solar tower and storage project – with some 1,700 towers – in 2018 from scratch? And at the cost they claim, with the reliability they assert.

Truth is, we don’t know. Solastor might have got their numbers down pat, this may well be the great breakthrough in solar technology – using huge lumps of graphite to store energy reflected from the sun – that the world has been waiting for.

But what raises the red flags is Solastor’s claims about the competition. In their rush to promote themselves, over and above their apparent competitors, presumably including SolarReserve’s 110MW solar tower and storage plant, the Solastor people have made some claims that are simply not true.

Take, for instance, the claims about rival big solar towers being “bird killers”, that molten salt storage technology is a “fire risk”, and that it relies heavily on gas generation.

Such claims are plucked from the fossil fuel doubters of renewable energy and the press that support them. But both the SolarReserve 110MW facility in Nevada, and Gemasolar’s long running 20MW facility in Spain – the only two large scale operating solar tower and storage plants – disprove these claims.

They do not need gas, and they do not use gas back-up power; Gemasolar’s facility has turned into a bird sanctuary, not a killing field, and SolarReserve has proved its technology is not a “death-ray”; and when pressed Solastor couldn’t provide an example of a “fire risk.”

I asked Solastor’s executive director Steve Hollis, a former coal industry executive and former CEO of Snowy Hydro, and fellow executive director Philip Hall about these claims.

Of the need for gas generation? “That is the information we received,” they said.

Of the bird kill? “That’s what we read in the press.” Of the supposed threat to pilots, also cited, and also disproven? Same source.

For goodness sake. The last thing that the industry needs is the repetition of media myths. Solastor might have been better served comparing themselves with coal plants. On their proposed numbers, they beat existing coal plants on cost as well, and thrash gas by some distance.

Solastor even repeated the fossil fuel talking point about “intermittent” solar and wind needing “like for like” back-up from fossil fuel generation, suggesting that this is not factored into the cost of wind and solar.

Again, this is a misrepresentation. In South Australia, wind and solar are providing nearly 50 per cent of demand without the need for any more “back-up” fossil fuel generation than was already built to “back up” and supplement “reliable” “base load” coal power. In fact, a lot of the back-up generation has been switched off.

Many in the solar thermal industry are appalled – not by Solastor’s ambition, but by the needless claims made to justify their presentation.

“We’re trying to get this industry going, not trying to kill each other. It’s very disappointing,” said one person involved in the solar thermal industry.

Another said: “There is certainly a lot of nonsense in their documents. A bit of a shame really as I do think the technology could have good potential.”

Of particular note was Solastor’s claimed capacity factor, producing 1.2 million megawatt hours from a plant running at 110MW in winter and 170MW in summer. That equates to a capacity factor of nearly 98 per cent.

“That is a bit silly,” said one expert, noting that not even “baseload plants” such as the most reliable nuclear and coal don’t run at more than 90 per cent. “Getting an actual 100% capacity factor would however be near impossible with any storage technology.”

And who needs baseload anyway? SolarReserve and Gemasolar’s technology is based on being “dispatchable”, which means an ability to provide power when needed by the grid operator, or by the customer.

In a modern renewable energy system, such as South Australia’s, when rooftop solar PV provides all of demand on some days within the next decade, that means filling in the gaps, not providing baseload.

“The market doesn’t need baseload and it (baseload) doesn’t provide the best return on investment. A system configured as a medium/peaker targeting evening loads is most valuable. Salt systems can as easily be built with 15 hours storage for baseload also if that is wanted.”

Solastor’s claims on costs also raised some eyebrows. It claims “molten salt” costs $180/MWh. The molten salt storage people have already suggested their technology is well below $150/MWh. Solar PV is likely to be significantly below $370/MWh even when paired with battery storage.

So how does Solastor get to 4c/kWh? Hollis says it’s because the company’s heliostats are about 50 per cent more efficient than its rivals. That means significantly lower capital costs. That means lower cost per kWh. He was absolutely certain that his numbers are right.

Let’s hope so too. The last thing that the industry needs right now is for silly claims to be made that can only lead to disappointment. That would send the whole industry backwards.

Keith Lovegrove, a solar thermal expert at ITPower, said his experience with energy technologies in general and CST in particular is that system scale-ups with size increases by factors of 10 at each step are the sensible path.

“If Solastor can build and prove the 1MW pilot system in Australia then they could move forward from there. Talk of power stations in the 100’s of MW takes some years to develop,” he noted, adding that private sector finance needed for utility-scale systems looks to see that a technology has been proven and ‘derisked’ at a smaller scale before investing.

“Solastor have a great technology idea with strong potential, but they will need to avoid the trap of over-selling in the early stages that many others have fallen into,” Lovegrove said.  “They should also be careful about making unduly negative claims about the incumbent molten salt approach, which is actually extremely effective.” Others in the industry made similar points.

Oliver Yates, the CEO of the Clean Enegy Finance Corporation, said he was a supporter of solar thermal technologies, and was keen to see technology costs move down the curve. He noted nearly every player in the market had been to see him or his team.

Yates would not comment on Solastor’s claims, other than to say – in reference to the recent cost curve fall in solar PV in particular: “One things I’ve learned is not to have a closed mind.”

So, if the CEFC does throw some money into the ring, and if there is, as Hewson suggests, a bank willing to fund the entire project, let’s hope they are doing some due diligence.

We don’t need any more failures like we had in the Solar Flagships disaster and the other “favoured” projects from the government-selected grant-making that characterised the failed wave power, Whyalla “solar dish” and geothermal projects. The future is more important than that.

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