The lights are off, the house is quiet and nothing seems to be running. But electricity is silently flowing through the plugs in your home. This hidden drain is known as phantom energy.

Also called vampire energy, the wasted electricity comes from leaving devices plugged in when they’re not in use. That could range from household items such as phone chargers and microwaves to TVs and gaming consoles.

This wasted electricity accounts for about 5% to 10% of home energy use, depending on factors like the age of the equipment, according to Alexis Abramson, dean of the Columbia Climate School.

“Phantom energy depends on … what kind of systems you have and how much they’ve improved over time,” said Abramson.

For example, televisions that are connected to the internet and have smart wake features that allow them to interact with phones and other devices can consume up to 40 watts of energy during the hours of the day that the TV would normally be off, according to Matt Malinowski, director of the buildings program at the American Council for an Energy-Efficient Economy. That’s almost 40 times as much as a regular television.

“The good news is there have been new, renewed efforts to tackle this,” said Malinowski.

He said advocates and manufacturers have come up with a voluntary agreement seeking to reduce the amount of energy smart televisions use when they’re in standby mode.

Phantom energy contributes to climate change because power drawn by unused devices can increase demand for electricity from sources that release planet-warming emissions. Aidan Charron, associate director of Global Earth Day, said that while the amount may seem small when a person looks at their individual utility bill, the environmental toll of phantom energy is significant when multiplied over homes across the country.

“Just take a little step of unplugging the things that you’re not using,” said Charron. “It will save you money and it’ll save emissions in the long run.”

What you can do

Some of the main culprits when it comes to draining energy are appliances that are constantly connected to electricity, such as those with a clock.

“Do you really need your microwave to tell you the time, or can you unplug your microwave when you’re not using it?” said Charron.

While unplugging devices may seem burdensome, it significantly contributes to reducing emissions.

Charron recommends starting with small steps like unplugging chargers for phones and other devices once the battery is fully charged. The next step is moving to other appliances such as unplugging an unused lamp.

If unplugging sounds too hard, regularly checking your settings and disabling any extra feature you’re not using that could be draining energy help, too. For example, smart televisions often have optional features that can be turned off so the television isn’t listening for signals from other devices while in standby mode.

“If you’re not using it, then you’re getting no benefit, yet you’re paying the price and increased the energy use,” said Malinowski.

How individual actions can make a difference

Individuals also tend to take more sustainable actions, such as unplugging devices, once they learn what they can do to decrease their household emissions efficiently. Those actions could contribute to reducing U.S. emissions by about 20% per year, which equals about 450 tons (408 metric tons) of carbon dioxide, according to Jonathan Gilligan, a professor of earth and environmental science at Vanderbilt University.

The choices individuals take in their daily lives all add up, Gilligan said, mainly because of how much the U.S. population contributes to direct greenhouse gas emissions.

“The question becomes, what can we do to try to address this?” said Gilligan. “Phantom power is one part of this.”

The more individuals decrease their footprint, the more likely it is that others will follow, too, and eventually, those actions may turn to societal norms, according to Gilligan, because individuals don’t want to feel like they’re being irresponsible.

“This is a place where psychologists find that this effect is real. If people see that other people are doing actions to reduce their greenhouse gas emissions, they want to do that” said Giligan.

When it comes to daily choices, individuals may think what they’re doing isn’t really making a big difference. But what they tend to overlook is how they influence others around them by choosing to live a more sustainable life.

The impact may be much stronger than a lot of people realize, Gilligan said.

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Microsoft has teamed up with Barclays on a novel approach to tackling artificial intelligence (AI) and optimisation problems based on a scalable analogue optical computer (AOC) architecture, designed to use consumer-grade technology.

The approach, described in a paper published in Nature, overcomes the Von Neumann bottleneck that occurs in classical computing architecture, where performance is limited by the speed with which data can move between memory and the central processing unit. The authors of the paper discuss an approach that eliminates digital-analogue conversions and the need to merge compute and memory.

In doing so, they said the AOC can achieve substantial efficiency gains in certain circumstances. They projected that the AOC would deliver performance of around 500 tera-operations per second per watt at 8-bit precision, which they claim would make it over 100 times more efficient than leading graphics processing units.

The Microsoft researchers combined 3D optical and analogue electronic technologies, using projectors with optical lenses, digital sensors and micro light-emitting diodes to build it. As the light passes through the sensor at different intensities, the AOC can add and multiply numbers, which is the basis for solving optimisation problems. 

In the Nature paper, the researchers describe how the AOC hardware is able to accelerate all the compute operations to perform five key operations required for solving optimisation problems: matrix-vector multiplication, nonlinearity, annealing, addition and subtraction.

The paper also discusses how Microsoft worked with Barclays to try to solve the delivery-versus-payment securities problem, which aims to find the most efficient way to settle financial obligations between multiple parties in compliance with regulations while minimising costs or risks within the constraints of time and the balances available.

Shrirang Khedekar, a senior software engineer with the advanced technologies department at Barclays, worked with the Microsoft UK Research team to create the dataset and parameters used in the research. Khedekar, who co-authored the Nature paper, said Barclays is interested in continuing to solve optimisation problems as the capacity of future generations of the AOC grows. “We believe there is a significant potential to explore,” he said. “We have other optimisation problems as well in the financial industry, and we believe that AOC technology could potentially play a role in solving these.”

Microsoft said it would be publicly sharing its “optimisation solver” algorithm and the digital twin it developed to enable researchers from other organisations to investigate its approach to analogue optical computing.

Francesca Parmigiani, a Microsoft principal research manager who leads the team developing the AOC, said that while it is “not a general purpose computer, what we believe is that we can find a wide range of applications and real-world problems where the computer can be extremely successful”.

She said the digital twin mimics how the real AOC behaves by simulating the same inputs, processes and outputs of an AOC in a digital environment.

“To have the kind of success we are dreaming about, we need other researchers to be experimenting and thinking about how this hardware can be used,” said Parmigiani.

Bi understood how far-fetched her allegations sounded. “If it were not for all the hard evidence, it’s too shocking to believe [Rebecca Smith] did what she did to kill my son,” Bi wrote on Facebook, using Smith’s real name. Perhaps a kind friend could have suggested to Bi that there were other explanations. Instead, Bi had a set of legal adversaries and a supportive echo chamber. On Facebook, GCs and IPs alike expressed sympathy for Bi’s tragic posts: Everyone knew bad surrogates existed, and based on Bi’s claims, it sounded like Smith was one. Aimee Eyvazzadeh, a Bay Area fertility doctor and influencer, called Smith “a criminal” and “a psycho.” Bi’s $1,275-an-hour lawyer, Elizabeth Sperling, wondered whether digging through social media posts might show Smith engaging in “strenuous activity” that could explain the death.

Bi’s husband focused on stabilizing the family, a move he credits with saving their marriage. He blamed the hospital, not Smith, but told me that the litigation is “her grieving process.” He tried to stay out of the legal stuff so that Bi couldn’t blame him too.

Smith had planned to go back to work shortly after giving birth. Instead, she couldn’t stop bleeding. Even though SAI had determined she hadn’t breached the contract, the escrow stopped paying, leaving Smith reliant on disability benefits as she faced an increasing pile of terrifying bills.

When Smith was finally cleared to return to work, a month after Leon died, Bi emailed Smith’s HR department to ask about her health plan. Bi also reported Smith to a federal agency, claiming that Smith was committing fraud. The stress on Smith was already high: Her supervisor at work had found her crying on and off for a day.

Smith hadn’t heard from Bi since her terse reply to the condolence email. Then, Bi texted her a screenshot of a Facebook post about another GC who’d had an abruption at almost 32 weeks—but that GC had called 911 and the baby had lived.

Next, Bi iMessaged a photo of Leon’s corpse to Smith’s 7-year-old son’s iPad.

In the months after Leon died, Bi:

Called the FBI 12 times. Reported Smith, SAI, the hospital, and Clarity escrow to more than a dozen state and federal regulators and numerous professional organizations. Launched a new round of her $30 million venture fund, backed by Marc Andreessen and David Sacks, President Trump’s “AI and crypto czar,” on Leon’s due date. Posted Leon’s ChatGPT-written endorsement from heaven, offering his “eternal blessings” for her work. Created TikToks, Instagram Reels, Facebook posts, X threads, LinkedIn Updates, and a website for her advocacy. Posted links disclosing Smith’s full name, photo, address, employer, mortgage license number, and son’s first name to her website. Asked her husband, again and again, how it was possible that Smith had carried her son but felt “nothing” about his death.

Bi has abandonment issues that she traces back to her twenties, when her father divorced her mom for the mistress who’d conceived his long-awaited son. She got on lithium for her bipolar disorder in early 2021 and began looking for surrogates as soon as she stopped feeling “sedated.” I spoke to the therapist Bi hired to consult with her and Valdeiglesias. She told me that, of the 792 intended parents she has evaluated for surrogacy or gamete donation in the last decade, she has declined to recommend only about a dozen. “I’m not gatekeeping,” she said. When it comes to serious mental illness, she added, it’s up to them to disclose. One of Bi’s fertility doctors, meanwhile, told me it’s not his place to scrutinize intended parents. He defers to the recommendation of the psychological interviewer.

If an intended parent gets turned down, they can usually find another therapist, another clinic, another agency. But without anyone questioning her plans, Bi seemed betrayed by the challenges of third-party reproduction. “Surrogacy is supposed to be the safest route,” she wrote on Instagram. It wasn’t just Leon’s death that pushed Bi into her spiral of legal action and social media posts. It was the apparent lack of control of having her child inside another woman’s body—the most basic fact of surrogacy.