Held once again in Düsseldorf, Germany’s huge exhibition center March 13–15, the 12th annual International Renewable Energy Storage (IRES) Conference and Energy Storage Europe Conference attracted roughly 4,500 international visitors, and more than 170 exhibitors, from over 60 nations.

While showcasing the latest in energy storage technologies, presenters discussed developing markets worldwide, offered detailed case studies, and explained how transforming renewable energy into hydrogen, both for storage and for additional applications, is becoming an ever-more cost-effective “green gas” solution.

Main themes at IRES (Figure 1) included flexible sector coupling and de-coupling as well as system-useful storage solutions that stabilize networks. Several speakers detailed how they see storage continuing to nibble around the edges of the grid as it’s currently configured. Many envisioned that, in the near-term, storage systems will essentially displace expensive fossil-fueled peaker plants, discharging banked emissions-free renewable-generated energy instead of relying on natural gas or coal.

Storage takes many forms: some of it is based on heat pumps and pumped hydro, some on banks of lithium-ion batteries, and now new hydrogen storage units. But all systems are geared to take advantage of ever-increasing amounts of cheap renewable energy from solar and wind. Indeed, as more renewables come online in Europe and worldwide, the need to balance load and demand as well as store intermittent energy has long been a driving factor. But as more comes online and prices fall, batteries-in-a-box container units and other mobile solutions are also finding niches both in “island” and distributed grids worldwide.

Last month, in a move aimed at bringing storage resources into wholesale markets, FERC directed regional grid operators to devise new tariffs for storage market participation that allow the resources to provide multiple electricity market services.

On Monday, a handful of market participants, including one regional grid operator, filed for rehearing on the proposal.

MISO noted that while the commission approved an order for storage resources above 100 kW, it deferred issues about aggregations of smaller distributed energy resources to a technical conference on April 9-10. FERC, it argued, should give stakeholders more time to devise how the outcomes of that conference will affect its compliance filing on the FERC order.

Other stakeholders argued FERC’s order goes too far, stepping into state jurisdiction over energy resources connected to the distribution grid.

TAPS argues FERC should require distributed storage resources to “make a binding choice” to participate exclusively either in the wholesale markets or at the retail level.

TAPS says it is seeking rehearing because regulators did not acknowledge or provide a reason for rejecting recommendations for an opt-out provision to storage rules. There is an opt-out provision in the commission’s demand response rules, and TAPS argues a similar mechanism should be put in place.

Xcel makes a similar argument, writing that allowing distribution-connected storage to provide both retail and wholesale services “oversteps the limits on the Commission’s jurisdiction under the Federal Power Act by interfering in state jurisdiction over retail sales and affecting the ability to preserve distribution system reliability.”

Ari Peskoe, director of the Electricity Law Initiative at Harvard Law noted in a series of tweets the TAPS and Xcel filings could potentially set up a challenge at the U.S. Court of Appeals for the District of Columbia Circuit Court if FERC rejects rehearing requests.

Elon Musk’s Tesla company last year built the world’s most powerful battery, but a new project means it could soon be out of the record books.

British billionaire Sanjeev Gupta is behind the development of a 120 megawatts/140 megawatt-hours storage facility, which will be larger than the 100 megawatt/129 megawatt-hours battery constructed by Tesla in Jamestown, South Australia, last year.

The new battery storage facility will be built at a location less than 100 miles from Tesla’s effort and be linked to a new solar farm at the Whyalla Steelworks, a site recently acquired by Gupta’s Liberty House firm when it bought Australian mining and materials company Arrium last year, ABC News reported.

The plan for another mega-battery reflects South Australia’s ongoing interest in renewable energy that was largely motivated by a widespread power outage that hit the state in 2016 during a huge storm. Described as a once-in-every-50-years weather event, the storm temporarily cut power for 1.7 million residents in Adelaide and the surrounding area, and served to focus the minds of local officials as they sought an effective solution to ensure that such serious outages could never happen again.

South Australia currently sources nearly 50 percent of its power from wind and solar, and according to outgoing South Australia premier Jay Weatherill, the new battery will “help underpin the long-term viability of the Whyalla steelworks, as well as provide additional benefits to the South Australian grid.” Construction will begin later this year.

The age of storage serving peak power has only just begun, so the size of that market is very much up for debate.

California has already halted a new gas plant in favor of deploying energy storage in its place. Elsewhere, regulators called on PG&E to acquire storage instead of paying to maintain two existing gas peaker plants. An Arizona utility recently procured asolarand battery project specifically to serve capacity for system peak hours.

These are early signs of a dramatic shift in how the grid gets electricity when demand is highest. “The amount of press written on storage as a peaker replacement has grown tremendously over the last several years,” said Paul Denholm, a researcher at the National Renewable Energy Laboratory. “My concern was, this might be exciting, but is there a real market there?”

When a new market appears and draws investment, it comes with the risk of proving shorter-lived than developers hoped. That dynamic played out in the early storage market for frequency regulation in PJM, which has mostly dried up due to oversaturation and rule changes.

Denholm and colleague Robert Margolis decided to test the market potential for storage-as-peakers, using load data and simulated solar PV production from California. Their new study suggests that peak power in California alone constitutes a massive market opportunity, which will continue to grow as solar capacity increases.

First, Denholm and Margolis established a baseline of how much storage could compete for peak capacity without any intermittent renewables to deal with. They modeled 4-hour storage, because that’s the threshold that California rewards with a full resource adequacy credit. As more batteries come online, they incrementally flatten the peak, eventually requiring longer-duration units to meet additional peak demands, as illustrated in the following chart.

The US Department of Energy recently floated the idea of carving out a place for small coal power plants in the distributed energy landscape of the future, but it looks like the agency’s latest attempt to save coal is a day late and a dollar short. In the latest development, GE has just begun pitching a new energy storage project with the evocative name The Reservoir, and it puts the prospect of a coal powered future where it belongs: on the shelf.

Last week CleanTechnica grabbed a few minutes on the phone with Eric Gebhardt, GE’s Vice President and Strategic Technology Officer, to get some insights into the Reservoir, and he had something to say that will bring little comfort to coal fans.

So, What Is The Reservoir?

When GE announced The Reservoir, it made the implications for renewable energyabundantly clear. GE described the new energy storage project as a “comprehensive” platform that “delivers a suite of customized storage solutions to help customers address new challenges and seek new opportunities in a rapidly transforming power grid that is becoming more highly diversified and distributed.”

That’s kind of a mouthful. What it means in practice is a lesson that grid planners have already absorbed: the old model of large scale, centralized energy generation is, well, old.  The rise of digital technology, renewable energy, and distributed energy have resulted in a “paradigm shift” in energy generation and distribution.

Gebhardt’s statement in a press release for The Reservoir is definitive on that score:

GE’s Reservoir platform enables cost-effective distribution, storage, and utilization of cleaner, more reliable power where and when it is needed most. It can fit into most any setting, from centralized grid systems to the most remote villages and communities. The Reservoir also allows energy providers new degrees of flexibility for more intelligently managing and getting the most out of all their power assets.

That sounds pretty fancy, right? The innards consist of a fairly standard lithium-ion energy storage arrangement of 1.2 megawatts and 4 megawatt-hours, but all the system control and operation overlays are exclusive to GE. The “reservoir” name evokes energy storage but it could just as easily refer to the storehouse of knowledge GE brings to the design. Here’s another snippet from the press release:

…It is a modular solution that integrates GE’s Battery Blade design (module stack design) with key technologies from across the company’s portfolio to achieve an industry-leading energy density, footprint and lifetime performance. GE’s proprietary Blade Protection Unit (BPU) actively balances the safety, life, and production of each battery Blade, extending battery life by up to 15 % and reducing fault currents by up to 5X.

Vertically integrated energy company Scottish Power has submitted a proposal to extend recently introduced battery de-rating factors in Britain’s Capacity Market to storage included in demand side response bids in what has been described as a latest attack on the battery market.

The utility submitted the proposal on 13 March, which would create DSR technology classes with different minimum durations, and apply the extended performance testing to these newly created groups.

Among these would be a ‘Storage DSR’ class, which National Grid’s electricity market reform delivery body would be obligated to consult on applying the lower de-rating factors to.

Scottish Power argues that under current market rules if a DSR CMU (Capacity Market Unit – “a unit of electricity generation capacity or electricity demand reduction that can then be put forward in a future Capacity Market auction” according to the government definition), consisting of energy storage, is located behind the meter (BTM) it will not be subject to duration de-rating.

“This risks over-rewarding such storage and increasing costs to consumers. It is also contrary to the CM policy of technology neutrality and unfair to other market participants,” the company stated.

It adds that without such a change, storage developers are able to bypass the extended performance tests which are applied to capacity storage generating technology classes by going behind the meter.

The proposal suggests that each applicant for an unproven DSR CMU “must include details of any known intention to use a generating unit that is categorised as a DSR storage technology class”, a suggestion that has been refuted by those offering behind the meter battery services for DSR.

The agreement will see Rolls-Royce combine its material science and technical expertise with Superdielectrics’ novel hydrophilic polymers that have been shown, in partnership with researchers from the Universities of Bristol and Surrey, to have potentially outstanding energy storage properties.

Dr Dave Smith, director of Central Technology, Rolls-Royce, said: “We believe that electrification will play an increasingly important role in many of our markets over the coming years and by working with partners on potential new technologies for energy storage we can ensure that Rolls-Royce is well positioned to take advantage of new developments.”

Jim Heathcote CEO of Superdielectrics, said: “We are delighted to be working with Rolls-Royce in the global race to develop advanced energy storage systems. This agreement gives us access to their unparalleled scientific and technical expertise. I hope this agreement will ultimately create new jobs and business opportunities in the UK.”

Working with researchers from the Universities of Bristol and Surrey, Superdielectrics has been developing hydrophilic materials, similar to those originally designed for soft contact lenses, to increase the electricity storage capabilities of capacitors, which store electricity by creating electrostatic fields.

These dielectric polymers may provide an opportunity to create capacitors that are able to rival – and even exceed – the storage capacity of traditional rechargeable batteries. The resulting supercapacitors may also be able to charge much faster than existing lithium-ion batteries.