Offshore Pumped Hydro Could Solve Clean Energy's Biggest Problem

By Haley Zaremba - Nov 13, 2025

• The world's transition to a net-zero future requires vast amounts of long-duration energy storage, a need that current lithium-ion batteries cannot fully meet because they can only store energy for a few hours.
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• Traditional pumped hydro storage, while simple and effective for long duration, is hampered by high costs, environmental disruption from massive dams, geographical constraints, and vulnerability to droughts.
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• Sizable Energy, an Italian startup, proposes an ocean-based pumped hydro system using inflatable membranes and seawater to create a gravity-based storage solution that avoids land competition, offers flexible deployment, and provides an affordable, grid-stability option for coastal countries.
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The global energy storage sector is heating up to be “clean energy’s next trillion-dollar business.” As more nations around the world become increasingly reliant on renewable energies to power their grids and the AI boom pushes clean energy expansion as part of an all-the-above approach to ramping up energy production as fast as possible, energy storage is becoming an increasingly critical component of energy security at local, national, and global scales. Researchers have estimated that a net-zero energy future will require a whopping 6TWh of energy storage. 

At present, the energy storage sector is powered by lithium-ion batteries. Lithium supply chains are well established, and the material is affordable while boasting a high energy efficiency rate that performs well in a wide range of temperatures. Major EV companies like Tesla have been increasingly devoting their money and attention to building up energy storage branches as storage has become a more lucrative and stable option. The scale of these lithium-ion battery packs has also been growing rapidly, with mega-batteries gaining serious territory in markets and on the ground.

But while lithium-ion batteries are nearly ubiquitous and have some key advantages, they alone will not be sufficient to maintain energy security and grid stability as the world increasingly electrifies. Even the biggest and baddest lithium-ion battery megapacks can only store energy for up to about four hours. That won’t cut it when trying to match clean energy production demand over days, seasons, and years. Long-duration energy storage will be critical for this aim, but the technology to accomplish this is still in its infancy.

The long-duration battery storage options currently in research and development phases are remarkably diverse, from “us[ing] the Earth as a massive battery” through Geomechanical Energy Storage (GES) technology to suspending enormous weights inside of high-rise buildings in urban centers. But the leading contender for commercially and logistically viable long-duration energy storage is pumped hydro storage.

This approach uses pumps to transfer water uphill, where it is contained until energy is needed on the grid. Then, the water is released to flow downhill, in the process rotating a turbine to create electricity. Pumped hydro is simple and already implemented in various contexts around the world, but it has yet to truly take off because it has some serious downsides. Massive dams associated with pumped hydro projects are hugely costly and environmentally disruptive. Moreover, the efficacy of these projects are threatened by prolonged droughts and lowering water levels driven by climate change. And smaller pumped hydro systems are simply too expensive, as each one has to be designed and engineered for its specific geography.

But an Italian startup thinks that it can build pumped hydro storage systems in an environment where all of these trade-offs can be avoided: the ocean. Sizable Energy has been trying to make this idea a reality since 2022, and is making notable headway. The startup has already done deepwater testing and secured $8 million in seed funding to build an offshore pilot demonstration project just last month.

“We are unfolding the possibility of building the system even before knowing exactly where you are going to deploy,” says Sizable co-founder and CEO Manuele Aufiero. ?“We do that by deploying offshore. Water is the same everywhere.”

The company’s model pumps seawater up and down a pipe attached to the seafloor for a gravity-based storage system. “Inflatable membranes form reservoirs at the bottom and on the surface; from above, it looks like a giant floating donut,” Canary Media explains. “The system connects to the land-based grid, and uses power to pump the brine up through the plastic pipe. Reversing that regenerates power.”

If the pilot project proves successful, this could be a potentially disruptive breakthrough for long-duration energy storage. The ability to deploy energy storage in the oceans would allow developers to side-step issues of land competition and provide a potentially affordable grid-stability solution to the world’s 154 coastal countries. 

By Haley Zaremba for Oilprice.com 

 When Trash Infests Our Oceans, Some Choose to Act

China's Green Revolution

by CGTN / November 12th, 2025

Every year, around 8 million tons of plastic waste finds its way into the world’s oceans. Some of this plastic takes centuries to break down. For the plastic that drifts to the coast of Zhejiang, China, a new opportunity presents itself. Here it is collected, brought ashore and given a second life thanks to the “Blue Circle”. With nature’s generosity in mind, a growing number of people is choosing to stand with the ocean.

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China Global Television Network, or CGTN, is an international media organization launched by CCTV on December 31, 2016. Read other articles by CGTN, or visit CGTN's website.

Halting Climate Change

by Bullfrog Films / November 13th, 2025

Scientists have come to call the first 6-8 months of the COVID pandemic “The Anthropause.” During this time, industrial fossil fuel pollution plummeted and for the very first time in history, world-wide emissions were reduced enough to halt climate change. In The Edge of Nature, Oscar-nominated, Emmy-winning director Josh Fox (Gasland, Awake, A Dream from Standing Rock, and How to Let Go of the World and Love All the Things Climate Can’t Change) isolates himself in a one-room cabin in the woods as he struggles with the physical and neurological effects of Long COVID and ruminates on man’s relationship with nature.

What is humankind’s role in nature? Is there such a thing as Nature? What does the word mean? The pandemic called into question everything that our civilization has done to dominate the natural world, from colonialism to the introduction of invasive species. During his nine-month seclusion in his beloved Pennsylvania forest, Josh confronts a legacy of genocide and intergenerational trauma that scars the surrounding landscape and grapples with his own history as the son and grandson of Jewish holocaust survivors.

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Bullfrog Films has become the leading US publisher of independently-produced documentaries on environmental and related social justice issues. Read other articles by Bullfrog Films.

 

Severe floods threaten global rice yields, study finds

New research finds damage to rice crops has accelerated in recent decades due to rainstorms that increasingly submerge young plants for a week or more. Adoption of flood-resistant rice varieties in vulnerable regions could help avert future losses.

Stanford University

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Severe flooding has slashed global rice yields in recent decades, threatening food security for billions of people who depend on the grain. The losses amounted to approximately 4.3%, or 18 million tons of rice per year, between 1980 and 2015, according to research from Stanford University published November 14 in Science Advances.

Damage has accelerated since 2000 due to more frequent extreme floods across major rice-growing regions, a trend likely to be exacerbated by climate change, the researchers found. 

Scientists and farmers have long understood that rice yields suffer during droughts. The new study adds to evidence of that damage, finding that droughts reduced rice yields by an average of 8.1% per year during the 35-year study period. But it also highlights a less studied threat. Although rice crops benefit from shallow flooding during early growth stages, too much water for too long can be devastating. 

“While the scientific community has focused on damage to rice yield due to droughts, the impacts of floods have not received enough attention,” said Steven Gorelick, the study’s senior co-author and a professor of Earth system science in the Stanford Doerr School of Sustainability. “Our research documents not only areas where rice yields have suffered due to past flooding, but also where we can anticipate and prepare for this threat in the future.” 

Defining ‘rice-killing floods’

The study clearly defines for the first time what makes a flood deadly for rice crops, said lead study author Zhi Li, who worked on the research as a postdoctoral fellow in Gorelick’s lab at Stanford and recently joined the faculty of the University of Colorado Boulder. 

A full week underwater during the plant’s growth cycle is the key threshold. “When crops are fully submerged for at least seven days, most rice plants die,” Li said. “By defining ‘rice-killing floods,’ we were able to quantify for the first time how these specific floods are consistently destroying one of the most important staple foods for more than half of the global population.”

To assess the damage from past droughts and floods, the scientists used information about rice growth stages, annual global rice yields, a global dataset of droughts and floods since 1950, a model of flood dynamics, and a simulation of soil moisture levels in the world’s major rice-growing basins over time. 

The new analysis suggests that in the next few decades, the most extreme week of rainfall across the world’s major rice-growing river basins could bring 13% more rain compared to the average for those regions during the 1980-2015 baseline period. 

Flood-resistant varieties can help

Greater adoption of flood-resistant rice varieties could help to avert future losses, especially in regions where the crop is at highest risk. These include the Sabarmati Basin in India, which experiences the longest rice-killing floods, as well as North Korea, Indonesia, China, the Philippines, and Nepal, where the impact from rice-killing floods has grown the most in recent decades. The largest losses overall have been in North Korea, East China, and India’s West Bengal. 

The research also uncovered exceptions such as India’s Pennar Basin, where floods appear to enhance rice yields. According to the authors, this may be explained by such regions’ hot, dry climates, which allow stagnant floodwater to evaporate quickly. 

For Gorelick and Li, the latest findings underscore the importance of understanding how rice yields respond to floods, droughts, heat waves, and cold stress individually and in sequence. Previous research has shown that sequences of weather whipping from drought to flood and back again result in nearly twice the rice yield loss compared to individual flood or drought events alone. According to the authors, “How these combined effects can be mitigated remains a major challenge.”

 

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Additional co-authors not mentioned above include Lorenzo Rosa, who is affiliated with the Department of Earth System Science in the Stanford Doerr School of Sustainability and the Department of Global Ecology at the Carnegie Institution for Science. The research was supported by a Dean’s Postdoctoral Fellowship awarded to Li by the Stanford Doerr School of Sustainability.

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Journal

Science Advances

DOI

10.1126/sciadv.adx7799 

Article Title

Severe floods significantly reduce global rice yields

Article Publication Date

14-Nov-2025

 

‘Almost half of the beaches will disappear by the end of the century,’ warns researcher

Coastal ecosystems are undergoing a process of crushing due to rising sea levels associated with urbanization. Marine scientist Omar Defeo, a professor at Uruguay’s University of the Republic, addressed this topic during the FAPESP Day Uruguay symposium

Fundação de Amparo à Pesquisa do Estado de São Paulo

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Omar Defeo, a professor at UdelaR, gives a lecture during the Oceanography session at FAPESP Day Uruguay 

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Credit: Karina Toledo/Agência FAPESP

By Karina Toledo  |  Agência FAPESP – Beaches around the world are undergoing a process of “crushing” due to a combination of rising sea levels caused by climate change and urbanization in coastal areas. This phenomenon not only profoundly affects the biodiversity living on the sand, but it also harms activities such as fishing and tourism. Additionally, it makes coastal cities more susceptible to the advance of the sea.

The warning was issued during the FAPESP Day Uruguay symposium, which began on November 13 in Montevideo, by Uruguayan marine scientist Omar Defeo, a professor at Uruguay’s University of the Republic (UdelaR).

“Almost half of the beaches will disappear by the end of the century. We in Uruguay, Brazil, and Argentina share these resources. Therefore, we must work in partnership with Brazilian scientists to manage and conserve coastal ecosystems,” Defeo said in his presentation.

As the researcher explained, the coastal ecosystem can be divided into three zones: the dune (post-beach), which is the area above the high tide line where sand accumulates due to wind action, forming mounds or “sand mountains”; the beach (beach face), a strip of sand exposed during low tide and submerged during high tide; and the submerged part (foreshore), which extends from the lower limit of low tide to the zone where waves begin to break.

“These zones form an interconnected coastal ecosystem that’s essential for environmental balance. How are they interconnected? The wind carries sand from the dry area to the surf zone [the submerged part]. And when the waves advance, they bring the sediment back to the beach. This bidirectional movement generates a constant exchange in which one zone feeds the other. When a storm comes, the dune acts as a buffer. So when urbanization eliminates the dune, the result can be the destruction of seaside homes,” said the scientist.

In a study conducted in collaboration with Brazilian researchers supported by FAPESP (17/17071-9, 18/22036-0, 18/05099-9, and 18/19776-2), Defeo’s group demonstrated that when one of these three coastal zones is compromised by urbanization, the effects harm the entire ecosystem. The study, led by Brazilian researcher Guilerme Corte, analyzed biodiversity at 90 locations along 30 beaches on the northern coast of São Paulo, Brazil.

The results, published in the journal Marine Pollution Bulletin, show that the number of beachgoers is the most impactful urbanization variable and correlates negatively with species richness and biomass, especially in submerged areas. The presence of buildings on the sand and mechanical cleaning activities also reduce biomass and species richness. Interestingly, abundance (number of individuals) was higher in locations close to urban centers. According to the authors, this is due to an increase in opportunistic species, such as polychaetes, which benefit from the supply of organic matter associated with human activity.

“Above all, the study showed that human impacts aren’t restricted to the place where they occur [on dry sand]. Stressors such as construction and high numbers of visitors on the upper part of the beach negatively affect biodiversity in the lower and submerged areas,” he said.

Another study conducted by Defeo in partnership with Brazilian scientists and published in the journal Frontiers in Marine Science showed that one-fifth of the 315 beaches analyzed around the globe have intense, extreme, or severe erosion rates. The group analyzed the various factors behind the phenomenon, including sea level rise, wind patterns, and waves. “We observed that human activities play a significant role, particularly on reflective beaches [with a steep slope that causes waves to dissipate their energy abruptly on the beach] and intermediate beaches [which have characteristics of both reflective beaches and calm or dissipative beaches],” he pointed out.

Defeo’s presentation took place during the first scientific session of the symposium, which was dedicated to oceanographic sciences. Other participants included Marcelo Dottori from the University of São Paulo (USP), who moderated the panel; Cristiana Seixas from the State University of Campinas (UNICAMP); and Natália Venturini from UdelaR.

The opening ceremony of the event was attended by Alvaro Brunini, president of Uruguay’s National Research and Innovation Agency (ANII); Marcio de Castro, scientific director of FAPESP; Raul Machado, manager of the Foundation’s Institutional Relations Advisory and coordinator of the symposium; and Brazil’s ambassador to Uruguay, Marcos Leal Raposo Lopes.

For more information about the FAPESP Day Uruguay symposium, visit fapesp.br/week/2025/uruguay.