1.25 MWh Battery For Puerto Rican Solar Power Plant
A 1.25 MWh Aquion aqueous hybrid-ion battery has just been commissioned to support a 16 MW Puerto Rican solar power installation. The 16 MW solar power plant is located in Salinas, and the Aquion battery will generate 100% of the electricity used to operate it at night.
“This project is a great example of large-scale base-load solar shifting using energy storage. Our batteries are optimized for long duration charge and discharge cycles, and base-load solar shifting is an ideal application for our technology,” said Aquion Energy CEO Scott Pearson.
Sonnedix commissioned the battery, which also has its own 250 kWp PV solar array. This company is an independent solar power producer with its US headquarters in Miami, Florida. (On its site, something of a philosophy can be found, “We believe in a world where the price of solar electricity is cheaper than fossil fuels, and the future of solar power is limitless.”)
So what is an aqueous hybrid-ion battery? It is one that uses a saltwater electrolyte, which is nontoxic and non-combustible. The cathode is manganese oxide, with a carbon composite anode. Non-corrosive reactions are used to help maintain the life of the materials.
Aquion already provided one of its batteries for an off-grid project in Hawaii. This battery was slightly smaller than the one in Puerto Rico and also had its own solar array.
It has been reported that the Aquion battery was the first to receive “Cradle to Cradle” certification, which resulted from the fact that it uses some recycled materials and some portion of it can be recycled when its use life is over.
Dr. Jay Whitacre created the first operational aqueous hybrid-ion battery at Carnegie Mellon University, and today the company has its headquarters in Pittsburgh.
Generally, lead-acid and lithium-ion battery chemistries are more common, but alternatives such as the Aquion batteries are also possible and claim competitive attributes and costs.
Image Credit: Aquion Energy
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Any chance to know financial details about the battery?
I dont know but there is a very interesting video on the site that is linked in the post. Also there quite a few dealers addresses on their own site actually all over the world. Looks like a great battery with incredable life time, 100% discharge and very tolerant to different abuses.
I call BS on that. life cycle of 3-5 years
Based on?
Their web site shows a graph of 5,000 cycles with no capacity loss. 5,000 cycles means over 13 years of daily cycling.
http://www.aquionenergy.com/application/files/2914/3751/2819/acq_cyclelife_chart_percentage_0.png
http://www.aquionenergy.com/energy-storage-technology
go back to their website and look at the spec sheet. 3,000 cycles to 70% retained capacity. Also I have internal docs from when my company was seeking products for integrate. Of course those numbers are extrapolated from lab test and are not real world.
There is only 1 battery chemistry that the national labs will even infer doesn’t degrade and that is vanadium. The reason they make the statement about vanadium is over 30 years of system field installations and testing. Other (mechanical and gelling issues) things may have been an issue but not capacity retention. Those other things have been resolved with improved chemistry mix and system redesign with industrial grade (pump propellers) parts which have a known replacement schedule.
I emailed the company and asked why the front page graph does not match the technical specs.
I’ll post back if I hear from them.
–
3,000 cycles to 70% would mean 8 years of daily cycling.
this battery has the same issue as lithium. You cannot ignore degradation like a walk in the park. When you deal with utilities and financing bankability it does not give certainty, even in pay for performance schemes. This type of stuff will only hurt the storage business. The 3,000 to 70% is a dead give away to lower cycles. That means battery swaps at an additional cost and I keep emphasizing what is now considered the key to increasing battery profitability. You will hear about this business model alot from utilities as they get educated on stacking benefits or what is now being referred to as “economies of scope” – that is, extending the value of the battery by finding multiple use cases for the “SAME FLEXIBLE STORAGE ASSET”. the case for extended storage value and subsequent revenue opportunities will be technology capability driven. Lithium and other chemistry platforms are a one trick pony. When it comes to that.
You want to know why Tesla and other lithium battery vendors cant make it work even in ISO areas where storage BTM storage can participate in the market?
those batteries cannot be a long duration battery for arbitrage (demand management) AND regulation services. Its either one or the other but not both. VRB can support a residential or commercial business for demand management while simultaneously providing regulation in the PJM if market rules allow. If you have a PV attached then the VRB can support the residential and commercial with renewable and simultaneously providing grid services. Avista Utilities is doing so with a vanadium flow battery on their grid. That is a fact.
I understand your flow battery pitch. But I’m not seeing them take over the storage business.
It’s ‘early days’. It will take some time to see what the market buys.
They may play a big part. They have one very good property – they separate power and energy.
I am not making a pitch. I am stating technical facts. And they do have traction. A little perspective here, in the US and global market there are only three viable VRB manufacturers, by viable I mean those (UET, Imergy and WattJoule) who have licensed the advanced vanadium electrolyte which allow for increased energy density, minimal hydrogen precipitation and increased ambient temperature operating range.
The base advanced electrolyte chemistry has already been approved upon so expect announcements very soon that improved vanadium chemistry are being deployed in the field.
There are other DOE improvements related to cell stack design that have been licensed but we will save for another day.
Back to my counter argument to you. Based on the background I gave you, obviously the barrier to entry for VRB manufacturing is high and so is the selection of system integrator because none really exist.
A flow battery is a significantly different technical platform and is simplistic at large scale and in manufacturing. A dc level redox battery is only missing the power conversion equipment. This is totally different then a dc lithium battery cell where the battery container is delivered and integration of control, power conversion components and auxiliary (HVAC, etc..) equipment takes place in the field .
VRB integrate (w/quality control) at the factory level and deliver a true plug and play ac system (no auxiliary HVAC or butler building) into the field.
Your inference that there is a anything but a first to market entry strategy in play here is incorrect. VRB manufacturers who have commercially deployed products have targeted the large scale utility-side market first.
Lithium has a head start due to patents that were in play for VRB up until the latter part of 2009 – 2010 period.
The current crop of advanced VRB vendors started deploying commercial product in 2014 so you are right on that note.
Most utilities still have a lack the of understanding of storage value to their grid. So when we start talking about economies of scope they have a hard time because they have only known one trick pony lithium and lead acid. And the lithium battery manufacturers are actively player hating.
VRB is not for every application. If you just need regulation or demand response we don’t recommend VRB.
VRB’s need to be used and cycled often or underutilization happens. But the key here it can be used for power “and” energy applications in a single flexible resource which extends utility or commercial benefits beyond the single use application of a lithium battery. It is the worlds most cost effective energy storage platform.
Think of it as the Swiss Knife of black box grid technology
you can send it signals for several different use cases as an input and get a suite of services across the power and energy application range.
You can’t do the same with lithium. Take a solar + storage power plant. The best you could hope for depending on whether the project is designed for power (regulation services or energy (load shifting, bulk energy supply) is 2-3 use cases.
lets take a power application. the battery would provide regulation services and no load shifting. It is physically impossible to do so due to battery coupling. Now you could add an auxiliary capacitor to make an already complex installation worse in terms of costs and maintenance and the gains would be incremental because if you use the one inverter you would still have to prioritize the grid or commercial services. VRB can simultaneously and autonomously provide regulation and voltage services over a dispatch service.
So it is first to market and education of end-customers but the Avista Utilities battery is educating a lot of utilities and grid operators and they are winning projects over Tesla and others when presented with the choice.
Avista is using a UET battery for system regulation, voltage support, VAR, renewable load shifting, system peak management (peak shaving) while supporting a BTM facility with 4 cycle ride through, UPS, back-up and black start capability.
All I am asking you to do is realize going forward utilities will start demanding more services for economic purposes from a single battery resource.
Very unlikely. It is very uncommon in this industry to share those details.
$350 per kwh. dc module cell price.
Pretty nice. $?
Battery companies almost never give out $$ stats… unfortunately.
The Aquion battery “dc module cell” price was quoted in a story about Duke Energy. The price was quoted as $350 per kWh
Confusion has recently arisen regarding these batteries. The original claim was “3000 cycles to 100% depth of discharge” now on the sellers site it is “3000 cycles to 30% depth of discharge” That is a huge difference and if correct makes these batterie quite uneconomical. Too bad, they were a shining hope for awhile. I still cannot understand how anyone could misrepresent the battery cycle life by that much and not get sued. They can indeed be discharge to 100% but apparently not on a regular basis. If anyone has more clarification about this please comment.
It is 5000 on their site without degradation. With no temperature management and with cheap components it should not be very costly.
Hi Green Greed. Why the name? Greed is good?
Maybe Green Cred. Or Bright Green. Or Green Excellence…
Well, the senior engineer at Aquion has graced us with some knowledge. He says “3000 cycles to 100% depth of discharge and 70% remaining”. Fabulous. The retail sites need to get their act together they are misinforming their potential customers. It is likely they just don’t have the technical know how to describe the battery properly.
More detailed response from Solar Choice website cut and pasted below:
Solar Choice Staff October 30, 2015 at 9:30 am
Hi Glenn,
I’ve asked Aquion’s Matt Maroon (interviewed in the above article) to address your questions. Below are his responses:
> Why does this battery have a guaranteed life of only 5 years?
The Aquion battery carries a 5 year full warranty with an additional 3 year pro-rated warranty for 8 years of coverage in total. This warranty coverage has proven to give our customers confidence in installing the AHI battery and be assured that it will deliver a daily cycle for 8 or more years (equating to roughly 3,000 cycles in total).
> What causes the battery to degrade over this time?
As with any battery, there are various wear out mechanisms that happen at the chemical level. For the AHI chemistry, the degradation is related to the amount of energy charged / discharged throughout the life. So if your application only calls for 50% depth of discharge, the battery will last double than cycling at 100% DoD. As more and more kWh of energy are stored and released from the battery the structure of the active materials gradually wear, being able to store slightly less energy than before. Degradation is not catastrophic which means that this battery is much more robust than other alternatives.
>> the Aquion battery will generate 100% of the electricity used to operate it at night <<
So the 16 MW array *consumes* (not produces) 1.25 MWh every night, provided by the battery. Did I read that right???
I’m not sure what power would be consumed by a solar array at night either? An explanation would be helpful. Maybe lights, alarm system and/or electric fence to protect their investment from thieves/vandals or animals?
Any lights, alarms, electronics, etc. would be quite minimal in their energy use. No significant amount of power is consumed by solar farms at night and the battery will be sending basically all its usable stored energy into the grid.
No, solar panels consume no electricity at night. Sure, if you don’t put a diode in to stop current flow solar panels can drain batteries at night, but I’m pretty sure they won’t just have an open circuit. And I’m sure they mean the battery will send stored energy into the grid at night, not that it will be consumed by the PV array.
We’re past the days of diodes as backpath preventers. Now we have active charge controllers which open the circuit if panel voltage drops below battery voltage. The earliest ones used relays but now they are solid state.
Thanks Ronald for your two comments. I have no idea how this setup can consume 1.25 MWh overnight. Earth to Jake: can you help us?
Yes, cost, and size would be interesting things to know. Assuming this is prototype-level installation, maybe some reasonable expectations for long term costs?
Regarding the statement “This project is a great example of large-scale base-load solar shifting ” – let’s put this in perspective. That 1.25 MWh battery will store about 5 *minutes* of the peak output of a 16 MW solar array. Enough to run this plant at night, OK. But I don’t think of 5 minutes as a large amount of base load shifting.
But the battery chemistry does sound interesting, and I hope some good comes of it.
Dont understand very well what this project is about but its definetly not better than german Neutrino INC project. They made a battery that gives energy for your whole home using neutrino energy. This tech was invented by Holger Thorsten Schubart who is the owner and CEO of NEUTRINO INC. They are actually prepearing more products than just a home battery.
But i really dont see what this costarican project want to achieve. Again a silly way like lithium or ion batteries to generate energy etc – this is previous centure. People need newer technologies
Are there Neutrino batteries in use now?
Lots of ideas. Lots of things look good in the lab. Few make it to the real world.
I briefly had a neutrino battery, but it passed through my hands, passed through the earth, and after 14 hours it overtook Voyager 2.
Butterfingers….
All right, if you’re so good I’ll send you a neutrino right now and see if you catch it.
From what I understand these batteries are already in the real world and can be bought at the 25kW size for residential or commercial. The 1.25MW size I assume is to just handle most of the peak tail after the Sun goes down.
they sell a smaller residential size battery. The battery is a 1.25 MWh size battery. Assume a 250 kwh battery with 5 hours of storage. This is for long duration applications not shorter one hour.
Hi all, I’m Terry Holtz, Senior Application Engineer from Aquion Energy. It’s nice to see so much interest and discussion. Here are a few points of clarification about our batteries:
Aquion batteries are designed for 3,000 cycles at 100% depth of discharge. After 3,000 cycles, the battery still has 70% of its original capacity available for use.
As for frequency of use, Aquion batteries can be discharged 100% daily, or on a regular basis, without damage.
Hope this helps, and let me know if I can answer any other questions.
Then your claim about no degradation is not accurate. Can it reach a high economies of scope – stacking of multiple services in both the power and energy range. In other words can you take a singular battery as a flexible resource and provide “satisfactory” regulation services in the PJM and renewable load shift for 3,000 cycles. If so can you do it simultaneously (without the hybrid configuration ?
Keeping in mind you are not doing that in the North Carolina Duke Energy project
Yes, this helps greatly. Make sure your retailers have accurate info as well.
wow!!!!!
Thanks, Terry.
Can you explain the graph on your site which show no capacity loss at 5,000 cycles? I pasted it in further up in the comments.
I am sure the people at Aquion are nice people and their intentions are good. But the play on words is less than upfront, unless the battery just drops to 70% capacity, instead of gradual over a number of cycles. Either way not good.
That graph is probably from early bench model testing, that too may be a slight of hand to get a marketing advantage.
I dont see any component drivers to put downward pressure on system cost since supposedly cheap materials and simple manufacturing process and costs are already included in the calculation for system prices.
With that being said, the price quoted in a article about Duke Energy/ Aquion collaboration was $350 kWh versus a lithium price of $450 kWh. I am pretty sure that was premium pricing to Duke (demo project) and not the wholesale market place.
Summarizing the World Energy Council earlier this year “focusing on ESS pricing is the wrong approach and does not reflect the real value of storage. In other words a ESS must be able to stack benefits to be cost effective and single applications will not be valued as much.