A new battery made from affordable and durable materials generates energy from places where salt and fresh waters mingle. The technology could make coastal wastewater treatment plants energy-independent and carbon neutral.
Salt is power. It might sound like alchemy, but the energy in places where salty ocean water and freshwater mingle could provide a massive source of renewable power. Stanford researchers have developed an affordable, durable technology that could harness this so-called blue energy.
The paper, recently published in American Chemical Society’s ACS Omega, describes the battery and suggests using it to make coastal wastewater treatment plants energy-independent.
“Blue energy is an immense and untapped source of renewable energy,” said study coauthor Kristian Dubrawski, a postdoctoral scholar in civil and environmental engineering at Stanford. “Our battery is a major step toward practically capturing that energy without membranes, moving parts or energy input.”
Dubrawski works in the lab of study co-author Craig Criddle, a professor of civil and environmental engineering known for interdisciplinary field projects of energy-efficient technologies. The idea of developing a battery that taps into salt gradients originated with study coauthors Yi Cui, a professor of materials science and engineering, and Mauro Pasta, a postdoctoral scholar in materials science and engineering at the time of the research. Applying that concept to coastal wastewater treatment plants was Criddle’s twist, born of his long experience developing technologies for wastewater treatment.
The researchers tested a prototype of the battery, monitoring its energy production while flushing it with alternating hourly exchanges of wastewater effluent from the Palo Alto Regional Water Quality Control Plant and seawater collected nearby from Half Moon Bay. Over 180 cycles, battery materials maintained 97 percent effectiveness in capturing the salinity gradient energy.
The technology could work any place where fresh and saltwater intermix, but wastewater treatment plants offer a particularly valuable case study. Wastewater treatment is energy-intensive, accounting for about three percent of the total U.S. electrical load. The process – essential to community health – is also vulnerable to power grid shutdowns. Making wastewater treatment plants energy independent would not only cut electricity use and emissions but also make them immune to blackouts – a major advantage in places such as California, where recent wildfires have led to large-scale outages.
Every cubic meter of freshwater that mixes with seawater produces about .65 kilowatt-hours of energy – enough to power the average American house for about 30 minutes. Globally, the theoretically recoverable energy from coastal wastewater treatment plants is about 18 gigawatts – enough to power more than 1,700 homes for a year.
The Stanford group’s battery isn’t the first technology to succeed in capturing blue energy, but it’s the first to use battery electrochemistry instead of pressure or membranes. If it works at scale, the technology would offer a more simple, robust and cost-effective solution.
The process first releases sodium and chloride ions from the battery electrodes into the solution, making the current flow from one electrode to the other. Then, a rapid exchange of wastewater effluent with seawater leads the electrode to reincorporate sodium and chloride ions and reverse the current flow. Energy is recovered during both the freshwater and seawater flushes, with no upfront energy investment and no need for charging. This means that the battery is constantly discharging and recharging without needing any input of energy.
Durable and affordable technology
While lab tests showed power output is still low per electrode area, the battery’s scale-up potential is considered more feasible than previous technologies due to its small footprint, simplicity, constant energy creation and lack of membranes or instruments to control charge and voltage. The electrodes are made with Prussian Blue, a material widely used as a pigment and medicine, that costs less than $1 a kilogram, and polypyrrole, a material used experimentally in batteries and other devices, which sells for less than $3 a kilogram in bulk.
There’s also little need for backup batteries, as the materials are relatively robust, a polyvinyl alcohol and sulfosuccinic acid coating protects the electrodes from corrosion and there are no moving parts involved. If scaled up, the technology could provide adequate voltage and current for any coastal treatment plant. Surplus power production could even be diverted to a nearby industrial operation, such as a desalination plant.
“It is a scientifically elegant solution to a complex problem,” Dubrawski said. “It needs to be tested at scale, and it doesn’t address the challenge of tapping blue energy at the global scale – rivers running into the ocean – but it is a good starting point that could spur these advances.”
To assess the battery’s full potential in municipal wastewater plants, the researchers are working on a scaled version to see how the system functions with multiple batteries working simultaneously.
The Latest on: Blue energy
[google_news title=”” keyword=”blue energy” num_posts=”10″ blurb_length=”0″ show_thumb=”left”]
via Google News
The Latest on: Blue energy
- Will Energy From Manure Help or Harm Water Quality in Michigan?on December 7, 2023 at 8:15 am
HARTFORD, MI – Gov. Gretchen Whitmer’s plan to generate all of Michigan’s energy from renewable sources by 2040 is meant to limit climate change gases. It also has consequences for improving or ...
- Dominion CEO Bob Blue on offshore wind, batteries, and the utility’s role in the energy transitionon December 7, 2023 at 4:00 am
Utilities aren't seen as bastions of innovation. But maybe no other entity is equipped to incubate the emerging tech desperately needed for decarbonization.
- Blue Jackets Get Cap & Roster Flexibility From Robinson Tradeon December 6, 2023 at 4:00 pm
The Blue Jackets have plenty of similar players to Robinson from a bottom-six perspective. They’ll miss his speed and energy. But in the end, the flexibility this creates was a more pressing need. The ...
- For Blue Jays, the show must go on with or without Shohei Ohtanion December 6, 2023 at 3:00 pm
The waiting might not be the hardest part — that will come should the Blue Jays fall short in their aggressively spirited bid for Shohei Ohtani. We apologize, but this video has failed to load. Still, ...
- Blue Energy Ltd (BLU)on December 5, 2023 at 9:10 pm
Risk Disclosure: Trading in financial instruments and/or cryptocurrencies involves high risks including the risk of losing some, or all, of your investment amount, and may not be suitable for all ...
- In pitch to Shohei Ohtani, how would Blue Jays likely make their case?on December 4, 2023 at 2:47 pm
The Blue Jays are reportedly one of the teams still in the mix to sign Ohtani, the two-way MLB superstar and two-time MVP.
- Blue Power: Can California Harness Clean Energy From Ocean Waves?on December 4, 2023 at 2:00 pm
California leased 600 square miles of ocean off its coast for floating wind farms. Now, the state is exploring ‘blue power,’ electricity from waves and tides for additional sea-based renewable energy.
- FSRPs: Blue Sea Power's floating solution to the energy crisis faced by Non-Interconnected Islandson December 4, 2023 at 9:09 am
Greece's Non-Interconnected Islands (NIIs) presently grapple with severe environmental and economic strains. The culprits are high-emission HFO/Diesel plants, sluggish renewable energy integration, ...
- Blue Ivy Carter Didn’t Have to Prove Anything on the Renaissance Tour. She Did It Anyway.on December 4, 2023 at 6:00 am
Before Blue Ivy Carter entered the world on Jan. 7, 2012, her life was already under attack. Her existence was questioned when her mother, Beyoncé, faced bogus fake pregnancy rumors, even after her ...
- New Energy Blue launches farmer-owned biomass businesson December 4, 2023 at 1:51 am
New Energy Blue, a clean-tech creator of biomass refineries that turn crop residues such as corn stalks into low-carbon fuels and chemicals, has announced the formation of New Energy Farmers LLC, ...
via Bing News