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Clean Power Catalina Island Battery Storage

Published on November 6th, 2014 | by Roy L Hales


Energy Storage Will Replace Many Peaker Spinning Reserve Plants

November 6th, 2014 by  

An interview with Troy Miller of S&C Electric

Originally Published in the ECOreport

The 150-kW storage system that S&C Electric installed at its Chicago headquarters is a model for the future. They needed a working demo to show their customers how they would benefit from energy storage. They can see how you can reconfigure the network if there is an induced fault. There is a small working demo of PJM’s frequency regulation market. The move to battery storage is inevitable, and enables the incorporation of much larger amounts of intermittent energy such as wind and solar. Troy Miller, S&C’s Manager, business development Power Quality Products, explained why battery storage will replace many peaker spinning reserve plants.


In North America, electric power is generated at about 60 Hz.

As electricity is more intermittent, fuel-powered plants are kept idling to ramp up quicker when there is a need for more power. They take minutes to respond and, in many cases, it has taken more than 20 minutes to minimize the mismatch between generation and loads.

“One of the benefits of energy storage is that it can respond in less than two seconds across the board,” Miller said. “If you are responding in seconds, you can take care of irregularities before they become a bigger problem,” he added. “If you have a frequency excursion and you arrest that excursion, then you remove the need for much of the spinning resources to take care of the secondary event.”

“So a comparatively small amount of energy storage that acts fast can displace a larger amount of spinning reserve generation,” he said.

Younicos, in Germany, claims battery storage technology can take the place of 25 fossil fuel burning plants, and enable the grid to carry 60% renewable content annually.

Miller said the percentage is up for debate, but battery storage will definitely enable more renewable content.


His response to Younicos’ claim that 5 MW of battery storage can displace 50 MW of conventional energy was an emphatic “Yes.”

“An energy storage device can provide resources both up and down, so it can source 5 MW and also you can charge the battery,” said Miller. “So it becomes a resource in both directions, as opposed to a spinning reserve which can only go in one direction.”

“You also asked if battery storage could replace peaking power plants and the answer is ‘yes,” he added. “We have a significant amount of generation online whose only job is to take care of the peaks as they occur. Energy storage is much more efficient.”

It can significantly reduce individual customer’s bills by shaving off demand and peak power.

Energy storage can do the same thing for utilities. Currently, an infrastructure that transmits 8 gigawatts normally  has to be built out to 19 – transformers, cables and everything – to be able to deal with a 19 gigawatt peak.

“If you could place storage strategically throughout the network so that you took care of those 8 gigawatts appropriately, you would not have to build up such a large infrastructure,” said Miller. “This would amount to significant savings globally across the grid.”

Catalina Island Energy Storage

Is battery storage the most important technology that will help us build the grid of the future?

“No, it is one of the many things that will be done,” Miller said. “It is one of the tools in the toolkit for the utilities to use. There are also things like demand response, intelligent switching, microgrid integration, distributed generation …”

Software also plays an important role.

S&C sells its CES-stored electricity to PJM through Intelligent Generation (IG).

“Our patented software enables S&C’s PureWave Community Energy Storage system to operate as a virtual power plant, and help system owners, like S&C, create new revenue streams for their assets,” said IG’s CEO, Jay Marhoefer, in a press release.

A company spokesperson explained how:

The IG software platform is an operating system for the distributed grid. On S&C’s behalf, we bid their PureWave Community Energy Storage system (ESS) into relevant PJM power markets and dispatch the ESS with the PJM signal. IG’s network consists of a fleet of different storage assets. The power of this network is that it allows us to simultaneously maximize electricity cost savings and generate revenues from PJM’s wholesale power markets. S&C’s ESS is extremely well-designed, allowing us to operate it and monetize it from IG’s data center with virtually no manual intervention required by S&C

Screenshot 2014-11-06 06.56.36

IG takes one frequency regulation signal from PJM –all participants in the market receive the same signal –and we allocate it to storage assets within our network. We then aggregate the responses from all the network assets and send this response to PJM. One of the values of the network is that we can tap into a subset of assets at a given time to provide PJM’s requirement, which most of the time is significantly less that the capacity we have bid. This means that assets within the IG network do not have to be operating 24/7, which increases efficiency and reduces wear and tear on each battery in a way that extends the useful life of each energy storage system.

According to the press release:

In order to sell into the fast-response frequency regulation market, PJM requires systems to pass a series of tests that measure the accuracy, delay and precision between PJM’s regulation signal and the system’s output. PJM rejects any system that does not meet a minimum of 75 percent; S&C’s system passed with an average performance score of 97 percent.

The system is now participating in the market on a daily basis,” says Tim Qualheim, Vice President – Strategic Solutions, S&C. “Our doors are open, and we are excited to welcome customers, industry professionals and regulators to see how we are making this system work for the grid and how to maximize the multiple benefits of energy storage.

Anyone who’s wishing to see a working model will find it at their headquarters in Chicago.

S&C has been selling their products into the US utility market since 1911.. They branched into Canada fifty years ago and have grown globally with projects in Europe, South America, Asia, and the Middle East. S&C has been facilitating the adoption of wind and solar technology for 15-20 years. They are an employee-owned company and entered the storage market a decade ago. S&C currently has about 47 MW and 146 MWh of storage capacity online. That is roughly 20% of the storage capacity in the world.

For further information go to S&C’s website @ or Intelligent Generation’s website @

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About the Author

is the President of Cortes Community Radio , CKTZ 89.5 FM, where he has hosted a half hour program since 2014, and editor of the the ECOreport, a website dedicated to exploring how our lifestyle choices and technologies affect the West Coast of North America. He writes for both writes for both Clean Technica and PlanetSave on Important Media. He is a research junkie who has written over 1,600 since he was first published in 1982. Roy lives on Cortes Island, BC, Canada.

  • Ronald Brakels

    Because of our high retail electricity prices, In Australia ancillary service providing energy storage appears likely to located in homes and businesses rather than on the grid, and that’s okay, it can still do the job. Provided it’s allowed to, of course. Incumbants are working on preventing it. Many larger solar installations in Australia are now forbidden to export electricity to the grid, which is evil as burning fossil fuels kills people and so delibrately chosing fossil fuel power over free clean solar power is murderous.

  • Massive steel milling equipment ran 25 hz motor-generators w/fly wheels from the turn of the century (twentieth). Massive like 5,000 hp motors and loads changing almost instantaneously. Some are still in operation today. I don’t know where I’m going with this. Except motors to convey fluids (vapors, liquids, and solids) use about 45 percent of the world’s electricity.

  • Matt

    In the Utilities defense, they have been in a controlled market where they were always cost plus. You could loose money if you tried. Now they have to react to a changing market.

  • bink

    There are also things like demand response, intelligent switching, microgrid integration, distributed generation …”

    what is this guy talking about? these are the services or functions that energy storage allow (gives them value)

    • jeffhre

      …and interconnections. Though storage (batteries) is great for very fast balancing at 50 or 60 Hz for EU and US needs. And it may even be adopted at small scales, for just that purpose over time. Which in the aggregate make make some difference with respect to grid based storage capacity. Though, IMO all of the above will expand faster before much storage is adopted, which could lead to the deployment of additional storage as a minuscule part of overall grid needs.

      • bink

        I see energy storage as the one piece of equipment that enables all of those services and functions to take place and that makes it cost effective because it can get paid for it all. Demand response exaggerators can’t do intelligent switching, microgrid integration, expand substation capacity nor support DG

        • jeffhre

          EV’s, microgrid storage, domestic emergency back-up, commercial user peak demand reduction facilities, existing pumped hydro, and who knows what else can emerge, could handle shifting the demand in the up direction. And demand response, done intelligently could serve effectively as an “area-wide switch” which works in the down direction – all long before direct grid storage is ever attempted at scale.

    • Mint

      Those things aren’t that valuable. The bottom line is that every service you mentioned is related to power capacity. DR is only as valuable as the power capacity otherwise needed to meet demand. DG only values power stored in batteries no more than power from FF generation. Etc etc.

      Spinning reserve is by far the most lucrative service that battery systems can target.

  • MrL0g1c

    So what do you guys think of this story then?
    California Public Utilities Vote No On Energy Storage

    • Adrian

      I think their larger customers will install storage to peak-shave and avoid demand charges, and the opportunity for the utilities to benefit from it will have passed before they even realize it is too late.

      • Bob_Wallace

        Good point. Utilities that hesitate lose business. Smart utility managers would get far out in front with solar and storage.

      • MrL0g1c

        Indeed, I think this is a simple case of the utilities not doing their homework, this article shows the clear value of storage.

    • Bob_Wallace

      I’d balance it off with this storage of how Southern California Edison is adding 250 MW of battery storage to their grid.

      Storage is going to happen in spite of small penny-pinching, ‘can’t see the future that’s about to run over them’ utility districts.

      (Plus, consider the source of that article. Not unreasonable to think that an Oil industry site would attempt to pour cold water on renewables.)

    • Matt

      I think they read 5MW battery replaces 50MW spinning reserve. Then think 1.3GW storage required in CA by 2020 means 65GW closed down spinning reserve. So yes they are a bit scared. Not to mention likely a lost opportunity to upgrade wires and pass on costs.

    • Mint

      That article is just looking at the current state of installed storage. Battery storage is just now getting cheaper than spinning reserve, and it’ll take a couple years to be cheaper than peakers.

      In Ontario, a 4MW (but only 2.6MWh) storage unit for frequency regulation was installed. So if your battery cells cost $300/kWh but had decent power characteristics, you’d only need $195 of batteries per kW of regulation power (plus all the other electronics). Spinning reserve costs $500-1000/kW, so you can see the potential.

      Peakers cost about the same per kW, but you’ll need 3-6kWh of batteries per kW of output to have decent peak shaving ability, so it’ll take a few more years to take that market.

      • bink

        Why cant you up size the battery to 4-7 kWh and do both?

        • Mint

          Economics. Peak shaving only makes economic sense when it’s well under $1000/kW. Otherwise, NG is cheaper up front and also more flexible (it can run continuously if needed instead of only 4-7 hours at a time). 4-7kWh of storage per kW of output would need battery costs of ~$100-150/kWh to get the whole system well below $1000/kW.

          If you have an environmental policy to minimize NG, then maybe you’re willing to pay more, but that’s only relevant 10-20 years down the road when we produce gobs of clean energy. At the moment, storing FF energy produced at night serves little purpose beyond economics.

          • bink

            What is NG (natural gas) ? what type of NG technology power plant ? because they do not all have the same attributes.

            I was referring to some storage technologies being able to follow load and quick response regulation with one piece of equipment.

            Regarding flexibility, NG power plant technology, not so much. The utilities use combined cycle gas turbine (CCGT) and gas turbines (GT) combustion turbine technologies to generate power and regulate the system.

            If there were flexibility in the technology then only one type of technology would be required. I think you should have been more specific and said ” NG is a flexible fuel”

          • Mint

            Bink, we’re not comparing CCGT to OCGT. Nobody asked that question. I’m addressing your question: “Why cant you up size the battery to 4-7 kWh and do both?”

            Consider two systems: System X has 100MW output, 100MWh of battery storage, and a slow-ramping (3% per minute) 100MW NG plant giving it auxillary power. System Y has the same 100MW output, but 700MWh of storage.

            Both systems have the same electronics to give you 100MW output in seconds, so X and Y are equal in capability and cost (maybe $50M). Let’s assume batteries cost $300/kWh, so for X the cost is $30M, and for Y the cost is $210M. Finally, X has the NG plant, which costs maybe $70M.

            Final construction cost: $150M for X, $260M for Y. Fuel cost for X’s aux power: 4c/kWh (assuming 8000 BTU/kWh, $5/MMBTU, but both figures could be lower). Cost to charge Y: grid cost (possibly as low as 4c/kWh with a deal).

            X can run continuously: as its battery gets below 50%, the aux power ramps up in 30 minutes to make the battery charge-sustaining (similar to a hybrid car). Y can run for 7 hours at full output, or 14 hours at half output, etc.

            So despite being cheaper, X is also more flexible.

            What I’m illustrating to you is the concept of marginal value. More storage only has value when it’s really cheap (well under $200/kWh) and/or when electricity cost is next to zero (e.g. in 20 years when solar surplus bring wholesale to 2c/kWh).

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