Energy storage is a tricky issue.

It is fundamental to management of the grid as the proportion of “variable” renewable energy increases.

Its economics are sensitive to the gap between high and low prices, its “round trip” efficiency, and its capacity to capture income from value adding services that stabilise the grid during transient events.

But more investment in storage means less revenue for each storage operator. Developers of large pumped hydro schemes and advocates for renewable hydrogen recognise that it will be difficult to compete with batteries, smaller pumped hydro and demand response to capture value from short-duration peaks and troughs in demand.

Accordingly, they are focusing increasingly on supporting seasonal variation as their core role. Hydro operators and hydrogen producers want to capture excess low-priced seasonal renewable electricity, then generate during supply shortages when prices are higher.

In light of all this, the above graph from the AEMO’s recently published Integrated System Plan is significant. It maps out how a seasonal storage plant might operate.

However, it also highlights—again—that Australian energy policy makers and investors lack focus on the demand side of the energy equation.

It is mainly demand side factors that drive the need for autumn top-up, along with heavy drawdown in winter due to limited solar generation, and the need for storage to build up during the summer.

We must therefore ask what activities are contributing to high demand. What potential is there for energy efficiency to reduce the seasonal variation in demand, not just the short-term peaks?

AEMO’s graph highlights a number of possibilities. The major factors underlying seasonal variation are poorly performing buildings, and inefficient heating and cooling equipment.

These include thermally disastrous buildings (both residential and commercial), widespread use of resistive electric heating and inefficient air conditioners, inefficient lighting, open shop doors, heat loss from poorly insulated hot water tanks and pipes, unnecessary use of pool filter pumps, inefficient industrial processes and so on.

Addressing these would reduce seasonal variation, along with the need for the seasonal storage and seasonal hydrogen-sourced generation shown in AEMO’s graph.

Global energy storage capacity is now expected to grow at a compound annual growth rate (CAGR) of 31 percent through 2030, according to Wood Mackenzie’s new global storage outlook.

The market will hit 741 gigawatt-hours of cumulative capacity by 2030.

Front-of-the-meter storage will continue to dominate annual deployments and will account for up to 70 percent of annual total capacity additions to the end of the decade.

Coronavirus and the global storage market
A 17 percent decrease in deployments is expected in 2020, a decline of 2 gigawatt-hours from our pre-pandemic outlook. The global storage market will see wavering growth in the early 2020s, but growth will likely accelerate in the late 2020s, enabling increased renewables penetration and facilitating the power market transition.

Energy storage is still a nascent market globally, but WoodMac observes that stakeholders — whether end consumers or big equity investors — are interested in continuing to invest in the sector and do not appear to be hindered by the pandemic and economic recession impacts.

If anything, the report notes, the transition may be accelerated as governments around the world grapple with how to recover their economies more sustainably than in the past, with upside for the energy storage industry.

U.S. home to half of all global storage capacity in 2030
The U.S. maintains its leading position and will make up over 49 percent (365 gigawatt-hours) of global cumulative capacity by 2030.

Utility resource planning in the U.S. is set to drive deployments over the coming decade. In the past two years, utility approaches to renewables and particularly storage have shifted seismically, as detailed in WoodMac’s latest Energy Storage Monitor report.

Managing demand on the power grid, at best a never-ending balancing act between generation and load, has become an increasingly complex and challenging responsibility. Along with the urgent need to reduce carbon-based energy generation, consumer demand for energy is continuously growing and shifting. As the energy landscape evolves, power providers across the country, from utilities to retail energy providers, are facing a combination of factors that present significant challenges.

New distributed energy resources, or DERs, are being developed and integrated at an ever-increasing pace, with electric vehicles and renewable generation assets (and their variability) being brought online faster than previously predicted. Indeed, solar photovoltaic and onshore wind are now the cheapest sources of new-build generation for at least two-thirds of the global population, according to Bloomberg New Energy Finance (BNEF).

Despite the impacts on new project deployments and the renewables supply chain due to the COVID-19 pandemic, renewable capacity additions this year are set to total 167 GW globally, according to the International Energy Agency’s Renewable Energy Market Update report. Overall global renewable power capacity is expanding and will grow by 6% in 2020.

1. Commercial and industrial (C&I) refrigerated facilities that serve food businesses have the highest power demand per square foot of any industrial load. These C&I refrigeration sites also consume more electricity from the grid than any usage category, other than lighting. Courtesy: Viking Cold Solutions

All these factors make it more challenging for utilities to meet and manage demand when and where it is needed. This is particularly true when considering food businesses with commercial and industrial (C&I) refrigerated facilities (Figure 1), which have the highest demand per square foot of any industrial load. C&I refrigeration sites also consume more energy from the grid than any other usage category other than lighting. Significantly, energy often accounts for up to 70% of the total electric bill for C&I cold storage companies.

This food supply sector, also referred to as the “cold chain,” is designated as critical infrastructure and is of vital importance—particularly during the type of public health emergency the world has faced over the past several months, and will continue to face until the pandemic is under control.

The House this week passed the Clean Economy Jobs and Innovation Act (H.R. 4447), pushing for innovation in clean energy, greater electrification of the transportation sector, efficiency in the home sector, and modernization of the grid at large.

Originally introduced by U.S. Reps. Tom O’Halleran (D-AZ) and Markwayne Mullin (R-OK), the bill would create an energy storage and microgrid grant, as well as a technical assistance program at the Department of Energy (DOE). These offerings would be made to a rural electric cooperative or non-profit organization. Working with at least six rural electric cooperatives, the goal would be to design and demonstrate energy storage and microgrid projects that draw from renewable energy sources.

“It also addresses the need for environmental justice by investing in grant programs for impacted communities and improving information sharing so Americans can be better informed about the risks in their neighborhoods,” Energy and Commerce Chairman Frank Pallone, Jr. (D-NJ) said. “It is a net win for our environment and economy alike. What’s more, it presents practical and achievable policies that have a real shot at becoming law this year after negotiations with the Senate.”

Proponents hope that the bill, which authorizes $5 million annually for the program from 2020 through 2025, would also provide well paying jobs wherever its funding went. It also received praise from the Energy Storage Association (ESA).

“By passing H.R. 4447, the Clean Economy Jobs and Innovation Act, numerous bipartisan proposals for promoting energy storage are moving forward, including increasing R&D and demonstration investments in energy storage technology, integrating storage across all DOE Energy offices, assisting rural customers with storage for resilience, and incorporating storage into public investments in transportation electrification and workforce development,” ESA CEO Kelly Speakes-Backman said. “ESA is pleased to support these efforts to ready the electric system for 21st century demands to provide resilient, efficient, sustainable, and affordable electric service.”

ENGIE EPS incurred increases in operating expenses and extraordinary costs due to COVID-19 which “more than offset” an increase in revenues that ENGIE’s energy storage subsidiary earned in the first half of this year.

European utility player ENGIE acquired a majority stake and rebranded the company, which had been spun out of a Turin University and known as Electro Power Systems, in 2018. It is engaged in delivering energy storage solutions including grid-connected large-scale project development and microgrids, as well as industrial solutions and e-mobility solutions.

ENGIE EPS just announced its first half of the year’s financial results up to the end of June 2020. Having already said following the first quarter of the year that the outbreak of the coronavirus was having a serious impact on the company’s work as well as its financial position, warning that it was unable to commit to providing full-year financial guidance, the company said its net financial position by 30 June 2020 had decreased to €-17.8 million (US$-20.76 million), down from €-8.1 million on 31 December 2019.

Although revenues and other income added up to €5 million, up 89% compared to the first half of 2019, owing strongly to growth in what ENGIE EPS terms ‘Giga Storage’ (utility-scale energy storage and solar-plus-storage projects) as well as industrial solutions including microgrids and commercial energy storage, a decrease in gross margins for Giga Storage activities, increases in operating expenses and extraordinary costs due to COVID-19 were greater than the sum of revenue increases. This was in part due to delayed construction schedules for projects including Sol Des Insurgentes, a 23MW solar farm in Mexico with 5MW of battery storage, now expected to be completed next year. 

However, ENGIE EPS appears to have a decent amount of work ahead to look forward to: it has won a few hundred megawatt-hours of ‘Giga Storage’ contracts worth more than US$130 million for projects in territories including Hawaii, Guam and New England.

The Guam projects are vast solar-plus-storage sites secured under 20-year power purchase agreements (PPAs) with the local Power Authority of Guam and in Hawaii ENGIE EPS was among successful bidders in the islands’ biggest renewables (and storage) tender to date, winning a 240MWh project under a 25-year PPA with Hawaii Electric that is currently before regulators to win approval.

Scientists from Far Eastern Federal University (FEFU), and the Institute of Automation and Control Processes of the Far Eastern Branch of the Russian Academy of Sciences (IACP FEB RAS) have studied a correlation between the shape of thermal energy storage (TES) used in traditional and renewable energy sectors and their efficiency. Using the obtained data, design engineers might be able to improve TES for specific needs. A related article was published in Renewable Energy.

The scientists studied a correlation between the shape and efficiency of TES based on granular phase change materials. When heated, such materials change their phase from the solid to the liquid state, thus preserving the heat energy. When they solidify again, energy output takes place. Devices based on this principle are used in advanced energy systems.

Using a computational model that had been developed previously, the team found out the effect of narrowing and expansion of cylinder-shaped TES on the process of their charging (energy input), energy storage, and discharging (energy output) depending on various preference criteria.

“To study the charging and discharging of TES with different shapes, we used six efficiency criteria. In some cases, a heat accumulator that stores more energy is the most preferable. In other cases, a unit with the fastest charge time is the most efficient. It is the same for discharge: some need a device with the biggest energy output, and some would prefer one with maximal time of keeping the outlet temperature not lower than a given value,” said Nickolay Lutsenko, a co-author of the work, a Professor at the Engineering Department of the Polytechnic Institute (School), FEFU, and a Laboratory Head at IACP FEB RAS.

According to the scientist’ research, TES with straight walls are often the most preferable. However, the shape of a unit can depend on efficiency criteria and the details of the process, such as boundary conditions, phase transition temperature, and so on. In some scenarios, narrowing or expanding TES can be more beneficial than straight walls ones.

Thermal energy storages can also be parts of other types of energy accumulators, such as adiabatic compressed air energy storages that are used to store cheap energy coming from traditional power plants in the night time or from solar batteries and wind turbines in favorable weather conditions. Energy output from these storage units takes place in peak energy consumption times, such as mornings or evenings.

Legislation to help the US economy invest in clean energy jobs and support innovation and industry passed the House of Representatives this week – and Energy Storage Association (ESA) CEO Kelly Speakes-Backman applauded the prominent inclusion of energy storage in the bill.

Next stop for the Clean Economy Jobs and Innovation Act will be the upper house of US Congress, the Senate. The bill includes wide-ranging measures on: energy efficiency, renewable energy, carbon pollution reduction technologies, nuclear energy, the electric grid and cybersecurity, transportation, research and innovation, technology transfer, industrial innovation and competitiveness, critical materials and environmental justice.

Energy storage is mentioned prominently for its role in renewable energy, with the bill calling for consideration of energy storage systems and coordination of programmes in renewables integration, as well as the development of assistance programmes for energy storage and renewable-powered microgrid deployment.

Energy storage is also mentioned in the context of enhancing electric grid reliability and its relevance to the supply chain for critical raw materials – like Europe, the US has put lithium and other materials used in battery making onto a list of such materials.

“Today the U.S. House of Representatives moved definitively to elevate the priority of public innovation investments in energy storage. By passing H.R. 4447, the Clean Economy Jobs and Innovation Act, numerous bipartisan proposals for promoting energy storage are moving forward, including increasing R&D and demonstration investments in energy storage technology, integrating storage across all DOE Energy offices, assisting rural customers with storage for resilience, and incorporating storage into public investments in transportation electrification and workforce development,” Kelly Speakes-Backman of the national ESA said.

“ESA is pleased to support these efforts to ready the electric system for 21st century demands to provide resilient, efficient, sustainable, and affordable electric service. We encourage members of the Senate to swiftly advance their similar legislation this Congress.”

Mitsubishi Power has signed a deal to help decarbonize US utility Entergy’s businesses in Arkansas, Louisiana, Mississippi and Texas, writes Rod Walton.

A major part of the collaboration will be focused on hydrogen-fueled technologies. Hydrogen does not contain a carbon atom and can be produced via electrolysis fueled by renewable or carbon-free nuclear resources.

“New technologies and innovative solutions to the challenges posed by climate change present opportunities for us to significantly decrease carbon emissions from our generation portfolio while maintaining low rates.

“We are pleased to welcome Mitsubishi Power as a collaborative partner in developing strategies to integrate these new technologies and solutions that support us achieving our environmental and customer commitments.”

Together, Entergy and Mitsubishi Power will focus on developing hydrogen-capable gas turbine combined-cycle facilities, green hydrogen production, storage and transportation; creating nuclear-supplied electrolysis facilities with energy storage; and developing utility-scale battery storage systems.“For two decades, sustainability has been a priority for Entergy,” said Paul Hinnenkamp, Entergy’s chief operating officer and executive vice president. “We have pledged to conduct our business in a manner that is environmentally, socially and economically sustainable that will benefit all our stakeholders.