SolarReserve’s baseload solar 260 MW Copiapó project bids into the grid in April, having just cleared Chile’s permitting with a Resolución de Calificación Ambiental.
With a price expected to be well under 10 cents per kilowatt-hour, the pioneering 24-hour solar project in Chile’s Atacama desert can compete on price against other baseload generation. Much of Chile has been dependent on pricy fossil fuel imports from its neighbors. But with more competition now from cheaper solar, in recent years, average prices bid into the central interconnected system (SIC) grid in Chile are down below 11 cents per kWh in 2015.
“We expect our power price to be well under what can be provided from any conventional fuel source, and emissions-free,” SolarReserve CEO Kevin Smith told CleanTechnica today.
Copiapó’s low price -0 for true 24-hour baseload solar — is possible because SolarReserve has combined dual solar technologies — photovoltaic (PV) and concentrated solar power (CSP) with energy storage — so it can supply electricity both day and night.
In a typical power purchase agreement (PPA), a plant is earning by the kilowatt-hour; so if it is generating 24 hours a day like Copiapó can, the developer is getting paid more daily, and can bid a lower overall price per kilowatt-hour, than if it was generating only 8 to 12 hours out of 24 like PV.
Smith told CleanTechnica that the 260 MW project will comprise 150 MW of PV panels for daytime generation, and two 130 MW CSP towers utilizing the company’s molten salt storage, for an installation of 410 MW between the two solar technologies.
By oversizing the CSP, SolarReserve can guarantee a round-the-clock baseload supply for a firm 260 MW at more than 90% capacity.
“Total installed capacity is 410MW, but different parts of the plant run for different hours to provide 260 MW 24 hours a day,” he said.
“We added CSP with storage to fill in the periods that the PV is off and to back up the PV. Look at a 100 MW PV facility for example. It ramps up and runs at peak output for 4 or 5 hours but as it ramps down at the end of the day it doesn’t make 100 MW. It makes maybe 60 MW as the sun goes down; so 50, 40, 30 MW and down to nothing.
“Whereas CSP with storage; we can turn on, and provide baseload non-intermittent supply, and then when we turn off, we turn off. So it has a different profile than you see in other renewable energy.”
Copiapó just received its environmental permits from Chile’s Impact Assessment System (Sistema de Evaluación de Impacto Ambiental — SEIA) which is administered by the Environmental Evaluation Service (SEA), the 260 MW project was granted the Chilean environmental permit, the resolution (Resolución de Calificación Ambiental / RCA).
Having a site fully permitted in advance of April’s bidding moves the project to the front of the queue in Chile.
“We think any kind of evaluation process will be scored by the project that is more advanced,” Smith said. “Typically in those bidding rounds they are looking for more advanced projects so we are also talking with a number of players to do direct power off take for them as opposed to bidding into the tender.”
SolarReserve expects to compete on cost with carbon combustion, even though Chile provides no renewable subsidies.
“This technology realistically has the potential to power the entire country of Chile using two phenomenal Chilean resources, salt and sun,” said Tom Georgis, SVP at SolarReserve.
Where Copiapó is sited, the SIC grid serves a heavy mining base. Many industries with heavy capital expenditures operate 24 hours a day, with multiple shifts. The mining sector in Chile utilizes multiple shifts, and needs firm power round the clock.
Pairing PV with its fellow solar technology, CSP, to firm up intermittency, rather than relying on battery backup has many benefits. CSP molten salt storage has essentially no limit on the number of times the molten salt is cycled through the tank, while batteries have short life cycle limits.
At this point CSP storage costs about $30 per kilowatt-hour of storage built, whereas batteries cost about $500 per kilowatt-hour of storage built. Battery storage would need to cut its price by 95% to be cheaper than utility-scale CSP storage.
Yet the PV industry has been slow to leverage the value of CSP’s cost-effective storage in solar PV/CSP hybrid plants like Copiapó.
“It is a little ironic the interplay between the photovoltaic and the CSP, it’s a little bit like the guys in the coal industry throwing rocks at the solar industry when it could work in unison quite well, because it’s a big playpen but, nevertheless the players don’t always get on the same train,” said Scott Frier, COO of Renewables at ACWA Power.
A native Californian, Frier developed the 250 MW Mojave and 280 MW Solana CSP projects for Abengoa before moving to the Middle East this year to join ACWA Power.
Crescent Dunes, SolarReserve’s first CSP tower with 10 hours of storage had a 13.5 cent/kWh PPA.
Its second project had a 12 cent/kWh PPA: Redstone, awarded in January is now being jointly developed with ACWA Power in South Africa, with 12 hours of storage.
As only the third project to utilize SolarReserve’s innovative RocketDyne technology, and taking it to its limits with 24-hour power generation; Copiapó is able to offer a lower PPA yet.
As the first solar plant to operate at a capacity factor and availability percentage equivalent to that of a carbon combustion power plant like coal, oil, or natural gas, but without the climate damage, the 260 MW Copiapó project also represents a game changer for solar energy.