The first element is pumped storage hydropower, a technology that has been steadily refined over the past 100-plus years. It is currently the most reliable, efficient and durable form of electricity storage. Pumped storage hydropower schemes are mainly found in mountainous countries, as they require a difference in elevation between two reservoirs, as well as sufficient amounts of water. When large volumes of power are generated, the excess electricity is used to pump the water from the lower reservoir to the higher one. If electricity demand increases, the water flows back down and drives turbines that in turn generate power. Pikl has implemented this principle completely underground. Subterranean tunnels are used to create the difference in elevation between the two underground reservoirs needed to produce electricity, regardless of the topography. This minimises the area required, and simplifies both the process of finding a location as well as the mandatory approval procedure.

Heat accumulators, where the thermal energy is stored, form the second component of the new storage concept. Thanks to its high specific heat capacity, water serves as an additional thermal energy storage medium for the underground pumped storage power plant. Renewable energy is used to heat the water to up to 90°C. Thermal energy is stored and used by means of heat exchangers installed in the underground reservoirs. When demand for heat is high, it can be supplied directly to consumers via district heating transmission lines.

Franz Georg Pikl also integrated district cooling technology into the concept – this method of cooling buildings is becoming increasingly significant – in the shape of absorption chillers. When required – in other words, on warm days – the hot water drives the chillers, which produce cooling energy that is distributed to customers along district cooling transmission lines. To ensure a constant supply of cooling energy to various temperature zones, this system can be modified by cooling the water of the underground pumped storage hydropower scheme – which could then be labelled a “cold-water pumped storage hydropower plant.”

Europe’s largest industrial energy storage facility has been inaugurated in Belgium.

The facility is a pilot project comprising energy storage and solar PV integrated with a microgrid. It is operated by CMI Energy at the company’s international headquarters in Seraing.

CMI makes industrial boilers, steam generators and HRSGs for concentrated solar power with thermal storage and the MiRIS (Micro Réseau Intégré Seraing) storage facility will help power the company’s headquarters, which currently consumes 1.3 GW a year.

CMI said that the plant is also intended “to demonstrate advanced integration of intermittent renewable energy resources with battery-based energy storage to produce a fully dispatchable renewable energy resource”.

CMI Energy president Jean-Michel Gheeraerdts said: “We now have ways to use green energy sources that eradicate their major flaw: intermittent production. Energy storage and management can be applied in a number of fields as an alternative to diesel generators for unconnected regions, as a way of deferring investment in parts of the network, as a means of optimizing existing photovoltaic or wind systems, and as an enabler of participation in the primary or secondary reserve markets.”

MiRIS consists of a 2 MW photovoltaic system with 6500 rooftop and carport panels, plus 4.2 MW of energy storage comprising a lithium-ion battery system and two different flow battery systems.

The technology showcase interconnects with the building’s electrical network and its DSO 15kV distribution service connection.

Gheeraerdts said that MiRIS “will facilitate investigation of the interoperability of renewables and different energy storage technologies for a variety of user energy profiles, particularly with respect to renewable energy time shifting and energy resale to the grid. MiRIS will also enable evaluation of microgrid ‘islanding’ operation, potential grid ancillary service opportunities, and the influence of user demand response.”

The U.S. residential energy storage market overtook front-of-the-meter installations for the first time in the second quarter of 2018, according to a joint report by Wood Mackenzie Power & Renewable Energy Consulting and the Energy Storage Association.

The incentive program from SRP comes in addition to new tariff structures from other regulated utilities in Arizona, which are expected to encourage more residential storage, Wood Mackenzie Senior Energy Storage Analyst Brett Simon told Utility Dive last month.

The study is “a landmark effort to understand the value” that distributed energy storage will have on customers and utilities, NREL said.

“Phase 1 is already underway,” Adarsh Nagarajan, NREL research engineer, told Utility Dive in an email statement. “The focus is more about collecting diverse data,” he said.

The first phase will manage granular resolution data on battery performance along with advanced battery testing data. Customer battery use and battery system performance data could be used in future stages of the NREL study “to develop modeling and simulation tools to assess the customer benefits and distribution network impacts of” battery systems.

The goal is to collect data from about 450 of the potential 4,500 SRP storage customers, according to Nagarajan. SRP reports that nearly 500 signed up, reserving their incentive. Battery systems charged by on-site renewable resources, like solar panels, are also eligible for the 30% federal tax credit.

Researchers in Akron, Ohio, are filling silos with sand in hopes it might lead to the next breakthrough in energy storage.

Echogen Power Systems, founded 11 years ago on the principle of capturing heat for energy, is among 10 recipients to receive millions of dollars in Department of Energy funding for long-duration energy storage.

In the Midwest, a team from Michigan State University was also selected. A common theme between the Ohio and Michigan projects: heating up cheap materials to reduce storage costs.

“In order to get a large penetration of renewable energy onto the grid, we really need low-cost and robust forms of energy storage,” said James Klausner, chair of Michigan State University’s Mechanical Engineering Department.

By storing thermal energy in relatively cheap materials, the researchers are looking for a low-cost, long-duration technology to support widespread deployment of renewables.

Echogen received $3 million and MSU received $2 million through a DOE Advanced Research Projects Agency-Energy (ARPA-E) program. The DAYS program focuses on storage for roughly 10 to 100 hours, and projects must also demonstrate a path to commercialization.

Echogen’s project turns thermal energy into electricity with sand as the storage medium. The process involves using a carbon dioxide heat pump cycle to convert electricity into thermal energy by heating a reservoir, which is converted back into electricity on demand. The product is geared toward larger-scale projects at 50-100 MW capacities.

“Using these low-cost storage media, we can keep increasing capacity for megawatt hours almost indefinitely,” said Echogen chief technology officer Tim Held, adding that storage durations could exceed 100 hours.

French power giant EDF has acquired a 50% stake in the Togo-focused unit of off-grid renewable energy specialist BBOXX, with EDF adding its financial clout to speed up solar home system deployments and its technical expertise to improve the energy storage offering.

The new joint venture seeks to progress BBOXX’s operations in Togo where it has been supplying solar home systems with batteries since 2017 and through which it now supplies power to 26,000 Togloese. The solar systems are eligible for mobile payments and they allow customers to power domestic appliances, such as TVs, radios, fans and mobile telephone chargers. So far BBOXX has opened 20 shops and employs around 100 people in this African country.

Along with its 50% stake in BBOXX Togo, EDF will aim to improve the performance of the battery storage solution, having been working on this technology as part of its Electricity Storage Plan, aiming to develop storage capacity of 10GW worldwide by 2035. EDF’s R&D department will also be testing and certifying solar kit components.

This is the latest investment from EDF into the African renewables sector, having been working in the Ivory Coast with Off-Grid Electric, recently starting operating in Ghana and offering solar pump irrigation solutions to farmers in Kenya. The firm has also been active in Africa’s utility-scale solar tenders under the World Bank’s ‘Scaling Solar’ programme, for example in Ethiopia and Zambia.

Under the new joint venture, EDF and BBOXX, which also plan to work together in other African countries, will first focus on the Togo government’s electrification programme, known as ‘CIZO’, which aims to supply more than half a million households with solar home systems by 2030. The two partners are aiming for a market share of 35% in Togo by 2024.

Mansoor Hamayun, CEO and co-founder of BBOXX, said: “Working with global partners like EDF shows our commitment to scaling up, mobilising greater investment, generating meaningful impact and powering the economic development of some of the world’s least developed communities.”

CMI Energy, part of Cockerill Maintenance & Ingénierie (CMI) Group, has opened an industrial energy storage facility called the Micro Réseau Intégré Seraing (MiRIS) in Seraing, Belgium.

Located at the CMI Group’s international headquarters, MiRIS features renewable, as well as energy storage systems, and is integrated with a microgrid.

The renewable portion of MiRIS includes a 2MWp, 1.75GWh per year, the photovoltaic system with 6,500 rooftop and carport panels, while the 4.2MWh energy storage part comprises a lithium-ion battery system and two different flow battery systems.

CMI Energy president Jean-Michel Gheeraerdts said: “We now have ways to use green energy sources that eradicate their major flaw – intermittent production.

“Energy storage and management can be applied in a number of fields as an alternative to diesel generators for unconnected regions, as a way of deferring investment in parts of the network, as a means of optimising existing photovoltaic or wind systems, and as an enabler of participation in the primary or secondary reserve markets.”

The company noted that its new energy storage pilot plant has been designed to demonstrate an advanced integration of intermittent renewable energy resources with battery-based energy storage to produce a fully dispatchable renewable energy resource.

Additionally, MiRIS will focus on the interoperability of renewables and different energy storage technologies for a variety of user energy profiles.

SERAING, Belgium — CMI Energy, part of CMI Group, will be inaugurating Europe’s largest industrial energy storage facility on October 26, 2018. The MiRIS (Micro Réseau Intégré Seraing) energy storage pilot plant consists of energy storage and PV integrated with a microgrid. The purpose of the full-scale pilot project is to demonstrate advanced integration of intermittent renewable energy resources with battery-based energy storage to produce a fully dispatchable renewable energy resource. MiRIS is located at the CMI Group’s international headquarters, located in Seraing (Belgium).

Jean-Michel Gheeraerdts, President of CMI Energy, when announcing the MiRIS project said, “We now have ways to use green energy sources that eradicate their major flaw: intermittent production. Energy storage and management can be applied in a number of fields as an alternative to diesel generators for unconnected regions, as a way of deferring investment in parts of the network, as a means of optimizing existing photovoltaic or wind systems, and as an enabler of participation in the primary or secondary reserve markets.”

MiRIS consists of renewable and energy storage systems. The renewable part includes a 2 MWp, 1.75 GWh/yr., photovoltaic system with 6,500 roof top and carport panels. The 4.2MWh energy storage part consists of a lithium-ion battery system and two different flow battery systems. The technology showcase interconnects with the building’s electrical network and its DSO 15kV distribution service connection. The existing facility consumes approximately 1.3 GWh/yr.

MiRIS will facilitate investigation of the interoperability of renewables and different energy storage technologies for a variety of user energy profiles, particularly with respect to renewable energy time shifting and energy resale to the grid. MiRIS will also enable evaluation of microgrid “islanding” operation, potential grid ancillary service opportunities, and the influence of user demand response.

A new-build school in the northern coastal suburbs of Perth, Western Australia, has become the first in Australia to be powered 100 per cent by rooftop solar and battery storage.

Atlantis Beach Baptist College in Two Rocks – which opened for business in February 2017 – sources all of its power, 24/7, through 20kW of rooftop PV and 30kWh of battery storage. Solar heat pumps are used for hot water.

The off-grid school initially chose to operate on diesel fuel generators, because the cost of connecting to the grid in early 2017 – around $250,000, according to the school’s principal – was ruled out as economically unfeasible.

The switch to solar – which was completed this month – was coordinated by Sydney-based company Upstream Energy, allowing the College to switch to solar and storage for no up-front cost.

To pay for the system, ABBC buys the solar power at a fixed rate from Upstream each month, just as it would do for grid power, with an electricity retailer.

Upstream says the solar and storage system – currently quite small – will grow in line with the campus, as more students enrol and more buildings are built. Upgrades will also come at nil capital cost.

At this stage, the school caters to students from pre-kindergarten to Year 10.

“The annual energy consumption of the campus is approximately 25,000kWh and the new solar and storage system will deliver up to 32,390kWh of sustainable energy at a substantially lower cost than what it would cost … to procure a grid connection,” Upstream Energy managing director Nathan Begley told the North Coast Times.

French multinational electric utility Engie has deployed an energy storage system in Holland that is powered entirely by second-life batteries from Renault electric vehicles.

The 150 kW/90 kWh E-STOR system in Rotterdam has been developed by UK energy storage technology developer Connected Energy and has been installed on a section of the TenneT distribution network.

The Rotterdam project is the first part of a three-stage project by Engie and Connected Energy. This first step is a seen as ‘proof of concept’, designed to demonstrate the technical and economic viability of using E-STOR second-life battery systems for frequency response services.

Engie says the results so far “are extremely positive: E-STOR has been proven to integrate seamlessly into Engie’s flexibility pool of industrial assets and has already generated its grid balancing revenues”.

In a wider context, the project is part of the Re-Use Re-Power initiative developed by Engie. Phase 2 and Phase 3 will see Engie and Connected Energy deploy much larger E-STOR systems at other sites in Northern Europe for grid balancing services.

The deployment at Rotterdam is also significant at a technical level: the E-STOR utilises a new system architecture which enables second-life electric vehicle batteries to be operated in series, which the company says thereby increases power and capacity while reducing cost.

A control room has also been built where the operations of the system can be demonstrated.

Connected Energy chief executive Matthew Lumsden said: “We are delighted with the positive results and feedback from the first stage of this exciting journey with Engie. Our second-life E-STOR battery containers have been proven to deliver on a technical and economic level: they should provide a guaranteed 10-year service in the frequency market with a substantial cost benefit versus new batteries.

“This is just the start of sequence of much bigger system roll-outs – 2019 is looking extremely promising indeed.”

Marcel Didden, project manager of the Re-use and Re-Power project, said: “Using second life car batteries is known to have technology challenges due to the different ageing history of the batteries. As this Rotterdam unit has been approved by the Dutch TSO to provide frequency reserve, Connected Energy has proven to manage these complexities.”

As well as Elon Musk remarking that the company may have had its “best ever quarter” for solar since the SolarCity takeover, Tesla’s energy storage deployments have enjoyed a ramp up, while a fellow exec hinted the stationary battery business is constrained by cell supply.

The solar roof tile remains delayed from reaching volume production until next year. Nonetheless, in an earnings call with analysts, Musk commented that “we saw higher revenues and better profitability in our energy business. In fact, it may have been our best quarter ever for solar”. Tesla CTO and self-professed battery tech fanatic JB Straubel said later in the call that cell supply is “somewhat tight” for the energy business which includes the Powerwall and Powerpack residential and grid storage products.

Tesla reported third-quarter energy storage deployments of 239MWh, an increase of 18% from the previous quarter (203MWh) and 118% compared to the prior year period. Energy storage continues to be the major catalyst in the segment revenue growth, which reached the second highest ever level of US$399.3 million. The company touted that due to the storage install growth, tripling of energy storage deployments in 2018, compared to 2017 was on track, despite expected seasonality issues in the fourth quarter of 2018. Supporting the growth claims was the eventual increase at Gigafactory 1 of its Powerwall production in the quarter, which was having an effect on reducing its order backlog.

Energy-Storage.news has reported on several grid-scale projects supplied or soon to be supplied with Tesla’s Powerpack battery systems during the quarter, including a contract to deliver a 52MWh storage system for a 280MW wind farm in Australia, the inauguration of New Zealand’s first grid battery storage facility and an order from Amazon for a 3.77MW system at the retail giant’s ‘fulfilment centre’ in Tilbury, England. Meanwhile the 129MWh battery Tesla put into operation in South Australia a few months ago is reportedly generating healthy revenues as well as network cost savings.

Julian Jansen, senior analyst, Energy Storage at IHS Markit pointed out that “strategically, it’s quite simple” for Tesla to serve both the C&I and front-of-meter market segments with the Powerpack, which is scalable to either or both sets of applications. This includes acting as supplier and integrator of Powerpack systems in the US C&I market for projects developed and operated by AMS (Advanced Microgrid Solutions). Jansen said that partnership alone equates to more than 100MWh of operational Powerpacks, based on publicly announced figures from AMS.