‘It was an accident’: the scientists who have turned humid air into renewable power

Source and full article: https://www.theguardian.com/science/2023/jul/02/it-was-an-accident-the-scientists-who-have-turned-humid-air-into-renewable-power

In May, a team at the University of Massachusetts (UMass) Amherst published a paper declaring they had successfully generated a small but continuous electric current from humidity in the air. It’s a claim that will probably raise a few eyebrows, and when the team made the discovery that inspired this new research in 2018, it did.

“To be frank, it was an accident,” says the study’s lead author, Prof Jun Yao. “We were actually interested in making a simple sensor for humidity in the air. But for whatever reason, the student who was working on that forgot to plug in the power.”

The UMass Amherst team were surprised to find that the device, which comprised an array of microscopic tubes, or nanowires, was producing an electrical signal regardless.

Each nanowire was less than one-thousandth the diameter of a human hair, wide enough that an airborne water molecule could enter, but so narrow it would bump around inside the tube. Each bump, the team realised, lent the material a small charge, and as the frequency of bumps increased, one end of the tube became differently charged from the other.

“So it’s really like a battery,” says Yao. “You have a positive pull and a negative pull, and when you connect them the charge is going to flow.”

For their recent study, Yao’s team have moved on from nanowires, and instead are punching materials with millions of tiny holes, or nanopores. The device they have come up with is the size of a thumbnail, one-fifth the width of a human hair, and capable of generating roughly one microwatt – enough to light a single pixel on a large LED screen.

So what would it take to power the rest of the screen, or indeed a whole house? “The beauty is that the air is everywhere,” says Yao. “Even though a thin sheet of the device gives out a very tiny amount of electricity or power, in principle, we can stack multiple layers in vertical space to increase the power.”

That’s exactly what another team, Prof Svitlana Lyubchyk and her twin sons, Profs Andriy and Sergiy Lyubchyk, are trying to do. Svitlana Lyubchyk and Andriy are part of the Lisbon-based Catcher project, whose aim is “changing atmospheric humidity into renewable power”, and along with Sergiy they have founded CascataChuva, a startup intended to commercialise the research. They first began working on the idea in 2015, some time before Yao’s team at the UMass Amherst. “We were considered the freaks,” says Andriy. “The guys who were saying something completely impossible.”

In fact, trying to prove the worth of an early proof-of-concept at conferences had them literally red in the face. He says: “The signal was not stable and it was low. We were able to generate 300 milliwatts, but you had to put all your effort into your lungs in order to breathe enough humidity into the samples.”

They’ve come a long way since then, with Catcher and related projects receiving nearly €5.5m (£4.7m) in funding from the European Innovation Council. The result is a thin grey disc measuring 4cm (1.5in) across. According to the Lyubchyks, one of these devices can generate a relatively modest 1.5 volts and 10 milliamps. However, 20,000 of them stacked into a washing machine-sized cube, they say, could generate 10 kilowatt hours of power a day – roughly the consumption of an average UK household. Even more impressive: they plan to have a prototype ready for demonstration in 2024.

More at: https://www.theguardian.com/science/2023/jul/02/it-was-an-accident-the-scientists-who-have-turned-humid-air-into-renewable-power

Scientists Solved the Mystery of How the Maya Made Plaster So Strong

Examples of head-scratchingly impressive building material can be found throughout the ancient world, and Maya lime plaster ranks high among them.

Scientists from the University of Granada in Spain explored why this plaster was a step above the building materials of its mesoamerican peers.

The secret ingredient was sap from nearby trees, introduced during the plaster-making process. The sap created insoluble crystalline structures (similar to those found on the shells of mollusks) that were well-suited to surviving the hot and humid climate of central America.

Full article https://www.popularmechanics.com/science/archaeology/a43658939/mystery-of-stronger-maya-plaster-solved/

Smart thermostat swarms are straining the US grid

Source: https://www.theregister.com/2022/07/13/smart_thermostat_strain

Smart thermostats, those unassuming low-power gadgets designed to keep homes at comfortable temps, are having an impact far wider than most might have considered, according to recent data.

A paper from Cornell University brings bad news for renewable energy enthusiasts – smart thermostats are secretly taxing the grid.

Smart thermostats, which the paper said were present in around 40 percent of US homes in 2021, are programmed by default to have different night and day modes. In hundreds of thousands of homes across the US that means a sudden jump in electricity use right before residents wake up – if people aren’t changing default settings, which the paper suggests is the case. 

Those hundreds and thousands of smart thermostats, typically configured to switch to day mode around 6am, “can cause load synchronization during recovery from nightly setpoint setbacks, increasing the daily peak heating electrical demand,” the paper said. 

Cornell professor Max Zhang and PhD candidate Zachary Lee, the paper’s authors, wrote that most studies predicting electrical demand fail to account for smart thermostats and the stress they can place on the grid.

“As we electrify the heating sector to decarbonize the grid, this so-called load synchronization will become a problem in the near future,” Zhang said.

To address the problem, Zhang and Lee built a dataset from publicly available smart thermostat logs collected by EcoBee that contained anonymized temperature, set point, runtime, and home occupancy statistics.

They used the data to examine energy costs during a New York City winter, and found that load synchronization often occurs before renewable resources, like solar, have had a chance to kick in and take stress off the grid. That stress is actually aggravating peak demand by 50 percent, the paper said.

Zhang and Lee also found that energy-saving mechanisms built into smart thermostats are less effective than advertised, with most homeowners only seeing energy savings of 5-8 percent, as opposed to the 25-30 percent they’re capable of. 

Thinking outside the home

The world is electrifying at an ever-quickening pace, and environmental problems have cropped up along the way. Electric cars create battery waste, as do other electronics, and removing carbon emissions from homes doesn’t mean power plants have dropped coal and gas in favor of sustainable solutions. 

Those solutions, like solar and wind, “require a considerable amount of real estate, and the right weather, and as a result they’re typically located far from the cities they would serve,” the Washington Post‘s Will Englund wrote

Smart thermostats increase frequency and magnitude of peak energy demand, and without more tenable ways to store energy from renewables, Lee said, they could offset greenhouse gas reductions from electrification.

Energy Fairness, a nonprofit allegedly funded by gas and oil interests, thinks that the challenges of electrification require emphasizing energy reliability above all else. Zhang and Lee’s paper, while not arguing for the retention of fossil fuels to support grid reliability, does suggest that close monitoring will be key.

“Future energy system planning must consider the interaction of weather, generation capacity, and energy management tools, show a large performance gap between potential energy savings and actual energy savings,” Zhang and Lee wrote.

Zhang suggests there may be an easier way to ease grid stress from smart thermostats: educate consumers on how to use them so default settings are changed. Even that may have its limits of effectiveness, though.

“In the end… we have to make smart thermostats even smarter,” Zhang said.

Sustainable Sources will go dark on Jan 18 to fight SOPA

On January 18 from 8am to 8pm, SustainableSources.com will join RedditBoing Boing and a growing number of other sites around the Internet in “going dark” to bring awareness of the need to loudly oppose SOPA and PIPA, the pending US legislation that creates a punishing Internet censorship regime and exports it to the rest of the world.

Let Congress know you OPPOSE H.R. 3261 “Stop Online Piracy Act” (SOPA) and S. 968 “Protect IP Act” (PIPA):

Opponents of SOPA: Google, Yahoo, Wikipedia, craigslist, Facebook, Twitter, LinkedIn, eBay, AOL, Mozilla, Reddit, Tumblr, Etsy, Zynga, EFF, ACLU, Human Rights Watch, Darrell Issa (R-CA), Ron Wyden (D-OR), Nancy Pelosi (D-CA), Ron Paul (R-TX)

Supporters of SOPA: RIAA, MPAA, News Corporation, VISA, Mastercard, Pfizer, Comcast, Time Warner, ABC, Nike, Walmart, Dow Chemical, Tiffany, Chanel, Rolex, Monster Cable, Teamsters, Lamar Smith (R-TX), John Conyers (D-MI)

Where does your Member of Congress stand on SOPA? (Project SOPA Opera)

SOPA and PIPA Are Too Dangerous To Revise, They Must Be Killed Entirely 

Congress needs to hear from you, or these dangerous bills will pass – they have tremendous lobbying dollars behind them, from large corporations reportedly hoping to prop up outdated, anti-consumer business models at the expense of the very fabric of the Internet — recklessly unleashing a tsunami of take-down notices and litigation, and a Pandora’s jar of “chilling effects” and other unintended (or perhaps intended?) consequences.

For example, Monster Cable considers craigslist a “rogue site” for takedown under PIPA – they want to prevent YOU from selling YOUR unwanted cables so they can increase sales! Many other “rights holders” want to do the same. Boycott anyone? There is an app for that.

Corporations pushing SOPA/PIPA want the ability to block you from reaching any web site they feel might be hurting their profits — without due process of any kind, or review in any court — by literally interrupting all Internet traffic to those sites via DNS at the ISPs and by censoring search engine results.  Incredibly, many lawmakers want to give them that right.

There is still time to be heard. Congress is starting to backpedal on this job-killing, anti-American nonsense, and the Obama administration has weighed in against these bills as drafted, but SOPA/PIPA cannot be fixed or revised — they must be killed altogether.

Sen Darrell Issa (R-CA) and Rep Ron Wyden (D-OR) are championing an alternative to SOPA/PIPA called Online Protection and Enforcement of Digital Trade Act (OPEN) that focuses on cutting off payments to foreign sites dedicated to piracy, and refrains from disrupting basic Internet protocols, or threatening mainstream US sites like craigslist.

Tim O’Reilly, a publisher who is himself subject to piracy, asks whether piracy is even a problem, and whether there is even a legitimate need for any of these bills.

Learn more about SOPA, Protect IP (PIPA), and Internet Blacklisting:

Neighbors and Fruit Trees

Not exactly green building, but sustainable none the less…

As long time proponents of edible agriculture and local foods, we were delighted to find the article Neighbors and Fruit Trees by Jim Hightower. The the websites referenced, www.fallenfruit.org, www.forageoakland.blogspot.com, www.neighborhoodfruit.com, and www.veggietrader.com all look useful, though the latter two are probably the ones I’m most likely to use as they’re both free and not limited to a specific geographical area. Happy eating!

Site Revision-June 09

In June 1994 Sustainable Sources put its first web page up. Like most websites of the day, it was pretty darn basic. But it was a good start. The site you’re currently viewing, launched 15 years later in June 2009, is the most recent in a long series of revisions.

There are many new changes:

  • The Calendar has been incorporated into the site, and is now available as an RSS feed (feel free to add it to your blog!). And be sure to add your events!
  • The Resources section has been moved to the right sidebar so it’s easier for you to find.
  • Sitewide searching (it may be a few days before Google indexes the revised site. Stay tuned)
  • RSS feeds on posts to the home page and comments on Draft sections
  • Easier navigation
  • And most importantly, we’ve set it up so that interested individuals or groups can take responsibility for a particular section.

It’ll now be much easier to add new sections, and we have a handful of Drafts already in progress. If you know a lot about ANY of the subjects covered here and would like to participate, please contact us! All the Draft sections allow user comments as well, so you can ask relevant questions, point out errors, and offer corrections.

It’s also easier than ever to list your company in the Resources section for any particular subject.

More changes will be coming as our web development schedule allows…