Published on September 20th, 2015 | by Tina Casey18
Energy Storage “Revolutionizes” Solar Technology & Beats Natural Gas, Says Abengoa (CT Exclusive Interview)
September 20th, 2015 by Tina Casey
Concentrating solar power technology has had its doubters, but throw in a big dose of energy storage and now you’re cooking with gas, so to speak. That’s our takeaway from a phone call we had last week with Fred Redell, Managing Director of global solar giant and concentrating solar specialist Abengoa.
The conversation was timely because just yesterday the Energy Department announced a new $102 million round of funding for solar projects, a gigantic slice of which is going to ramp up concentrating solar power (CSP) tech to next-generation status, and it just so happens Abengoa is one of the CSP awardees.
Solar Energy And Energy Storage
With that in mind, here’s what Redell has to say about the interplay between solar energy and energy storage:
For our solar thermal electric projects we’ve been adding energy storage in one form or another essentially all the time…they [CSP systems] inherently have a certain amount of energy storage just because of the thermal inertia of the project. Our towers have included steam energy storage mostly for operational purposes, and then our Solana project consisted of troughs with molten salt storage.
Our project in Chile coming up is a tower with molten salt storage and battery storage. What really matters is what grid you’re connect to, what that grid needs…and tailoring the product to fit those needs. A combination of energy storage can be very valuable depending on the grid.
The obvious part in the market now, in some locations, such as the southwest, California and Arizona, is a potential need for capacity as time goes by. Meaning, that more than just energy, the grid demands a need for capacity which gives value to the grid…and to do that with a carbon-free source is an exciting idea.
A couple of things will drive that. One is this idea of a “duck curve,” this need to be able to deliver on demand at certain times.
The next is policy. Progress may require the retirement of coal facilities. That capacity is taken offline and needs to be returned to the grid.
The other aspect to consider is that location really matters for capacity. You can’t really affect the grid from 3,000 miles away as much as you might want to. So there’s going to be a mix between energy storage that’s grid connected, energy storage that’s customer connected, and energy storage that will be generation connected.
We [Abengoa] want to participate in all those areas, from battery energy storage through thermal energy storage.
Our view of where we’re going with thermal energy storage, trough or tower connected, is that we want to provide a peaking style solar power plant, meaning that it is designed to collect the energy independently — as independently as that allows — from the solar resource.
Yes, Solar Can Do Baseload
Abengoa’s Atacama 1 CSP project in Chile incorporates a molten salt energy storage system with 17 hours of storage. Seventeen hours might seem like overkill, but Atacama 1 is serving a mining area with particular grid needs, for which the company provides with a battery energy storage system and photovoltaic cells in addition to the solar thermal system. Unlike the peaker-style concept, the idea is provide baseload service:
When you talk about 17 hours you’re heading toward a different product [from peaking style power plants], that will look more like a base load product, like we have in Chile. We’re going to deliver when the sun is out, and deliver through the entire night.
There are three “extremes” for solar. One is to do baseload, one is to do peaking, and one is what PV is doing very well in the middle of the day, which is providing the middle-of-the-day energy.
Yes, Solar Can Compete With Gas Turbine Peaker Plants
Last month CleanTechnica took note when Abengoa took a giant step toward getting its Palen CSP project off the ground, settling on a trough-style CSP system rather than a proposed tower system. The original permit was granted years ago for a trough system, so we racked it up as a win for solar opponents and a loss for the best available technology. However, as Redell explained in our more recent conversation, energy storage adds a powerful new twist to the financials of CSP:
Our decision to stay with the permitted [trough] technology is largely because we see an opportunity in the short term, of having a project that has a permit, that has essentially every approval needed to actually builds very valuable.
After…Abengoa acquired the project [from BrightSource], over the last year we’ve been studying what the market needs. We’ve really been looking at this idea that the market needs a solar peaker. We’ve studied it, and we think it is competitive with gas turbine technology.
…What we’ve looked at is, can we do this with the technology that we have. We arrived at the point that we didn’t see, in that [peaker] market, a distinguishable difference between trough and tower, when you revolutionize it with the storage potion and you’re trying to see it for capacity.
At the same time we did recognize that our biggest concern was with respect to timing, and uncertainty. If we were to approach it with a tower project, we would be looking at more uncertainty and a longer time. We do see that tower technology is really good. It has some advantages, and from a cost standpoint you’ll do a little better with a tower.
For this specific site, we could look at it and understand that there are concerns that a lot of people have. That doesn’t mean we don’t want to continue with towers, we’re just looking for other locations that are more suited for that technology.
Onwards And Upwards For CSP And Energy Storage
CleanTechnica has been making a similar point about solar energy for years, particularly in regards to thin film organic solar cells. Depending on the application, solar energy in general, and CSP in particular can be an economical solution even without the advantage of the absolute most efficient technology.
On the other hand, we’re all over absolute most efficient technology, and it looks like Abengoa’s track record of innovation is going to factor in to the next generation of highly efficient CSP systems.
Of the aforementioned $102 million solar funding package, Abengoa is one of 14 companies to split $32 million for cutting edge CSP projects. The company received a matching grant of just over $1.2 million to do this:
Abengoa will re-optimize the collector as an entire system to enable the use of molten salt in the collector field, detailing and validating innovative improvements in the concentrator design, drive and controls, manufacturing, installation, plant operation, and optical performance. This will result in a next-generation collector that moves away from the conventional architecture, delivering lower costs and better high-temperature heat transfer fluid compatibility.
And another matching grant of almost $2.7 million for this:
This project will use particles that represent a heat transfer material that can support cycle temperatures of 1,100°C or higher without complex freeze protection systems. The project will develop designs for a receiver using a novel heat pipe strategy, material handling and storage of hot particles, and ducting of hot, pressurized air.
So, stay tuned.
Photo credit (cropped): Solana trough-style CSP plant in Arizona via Abengoa Solar.
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