Why new coal? Solar towers + storage beats it on all counts

The US-based developers of the world’s leading solar tower and storage technologies has expressed surprise that Australia’s federal government is pursuing “new coal” plants, saying that solar towers with storage beats coal on just about all fronts.

Tom Georgis, the head of international development for SolarReserve, says solar towers and storage can match and beat coal on capability – providing baseload and flexible generation – and match new coal on cost, and provide zero emissions output as a bonus.

“This is just not a direction that financial markets are heading in,” Georgis told RenewEconomy in an interview on Tuesday, during a visit to Australia, where the company is hoping to build a $700 million, 110MW solar tower and storage facility in Port Augusta, and in other states too.

“In our opinion it is almost backward looking,” Georgis said, adding that carbon capture and storage in electricity generation is unproven and not cost-effective, and coal generation needs to take account of the impact of mining, and of emissions.

The Australian energy industry, including fossil fuel generators, have reacted to the Coalition’s push for new coal plants with a mixture of surprise and disbelief, saying any such plant is “uninvestable”.

Bloomberg New Energy Finance has estimated costs at between $138/MWh and more than $200/MWh, and significantly higher with CCS. It and others say estimate emissions reductions are grossly over-estimated.

SolarReserve says its own technology costs are “well under ” coal, even without CCS. It has been coy about its costs in Australia, having never built a plant here before, although CEFC executive director Simon Brooker told a Senate inquiry this month that a cost of around $150/MWh was being talked about for a first of its kind plant. Costs would then fall quickly as others are built.

SolarReserve is believed to be participating in a South Australian government tender for 75 per cent of its electricity needs, competing mostly with new gas stations and existing mothballed ones. It has talked with both the CEFC and ARENA.

Interestingly, Engie, the owner of the mothballed Pelican Point gas station near Adelaide considered to be its biggest rival in the tender, reportedly told the same inquiry on Monday that running the generator would not be economic, even with a government contract, because of the cost and availability of gas.

This may have prompted S.A. energy minister Tom Koutsantonis to say some positive things about solar towers and storage last week. Both the federal Coalition and Labor have promised to help promote solar towers, but have done nothing since the election.

Georgis says SolarReserve has already beaten gas generators on price in a tender in Chile last year, and is confident it can beat new gas generation in Australia too. Its main issue lies in the length of a contract, which will be crucial in its ability to secure finance.

Georgis again underlined the capability of solar towers and storage, and its ability to provide baseload power, power on demand, bulk storage, and use its steam turbines to provide the ancillary services normally delivered by fossil fuel generation.

He says battery storage will make sense for short-period needs, and as a cheaper option to network upgrades and for accompanying solar in distributed generation, but battery storage could not deliver or compete on price for bulk storage.

Pumped hydro was also unlikely to provide a “baseload” option, and was reliant on arbitrage opportunities (pumping water up hill while prices were low, and generating power when prices were high) to make it economic. Solar towers, on the other hand, had zero fuel costs.

SolarReserve has been operating its Crescent Dunes plant in Nevada – its first – for more than a year and the 100MW facility is delivering power to Las Vegas between the hours of noon and midnight. Its 1,100MWh of storage in that one plant is more than all the battery storage capacity in the US.

It is building a similar-sized facility, Redstone, in South Africa, and is bidding in a tender this year in that country to provide peaking power. About three 150MW solar tower facilities, with storage, are expected to be mandated.

In Chile, where the huge solar resources and resulting increased output pushes costs well below $100/MWh, SolarReserve is bidding another four or 5 towers in an auction scheduled later this year, and in Dubai it will compete for an auction for two 100MW solar tower facilities.

In China, mandates for 1GW of solar tower pilot plants have been awarded and SolarReserve is negotiating to provide its technology and services. It already has an MOU with Shenhua, the world’s biggest coal generator, for 1,000MW of plants and China plans another 5GW of solar towers and storage in the next 5 years.

Morocco is currently building solar towers and storage, albeit with a competing technology, and is looking to tender for more as part of its ambitious renewable energy target.

“The conclusion is that for a lot of international tenders, you have got to have storage,” Georgis says. “This is a viable technology, and cost-effective. It has most of the performance characteristics that customers need – baseload power, peaking capabilities and transmission and grid stability and reliability.

In Australia, SolarReserve is also pursuing opportunities in other states, particularly those with high state-based renewable energy targets such as Queensland and Victoria, and those with high solar resources, such as Western Australia.

“We have always promoted that solar towers and storage can do all the above, firming and shaping, ancillary services, provide the power, peak or baseload, bulk storage and deliver zero emissions,” Georgis said.

“We are certainly much more cost-effective than the mis-named ‘clean coal’ technology.”