Energy efficiency

My colleagues and I have developed an artificial intelligence system that helps buildings shift their energy use to times when the electric grid is cleaner. I’m an engineer who studies and develops smart buildings. My lab created Merlin, which learns how people use energy in their homes and adjust energy controls like thermostats to meet their needs while at the same time minimizing the impact on the grid. The system can learn on one set of buildings and occupants and be used in buildings with different controls and energy use patterns. We dubbed it Merlin after King Arthur’s legendary magician to reflect the magical nature of the system: It automatically collects data on how people use energy in their homes and identifies opportunities to charge and discharge home battery storage. And it does so in a way that you always have power for whatever you need. So your air conditioning is always available, but at the same time it reduces the strain on the grid – for...

Reading down the lengthy final agreement of the COP28 United Nations climate conference held in December 2023, you’ll go a long way before finding a strong, active verb. The lengthy recitation of climate impacts “notes with concern” and occasionally with “significant concern” glaring gaps in countries’ current policies. But while countries volunteered pledges to act, they were less keen to have those pledges framed as binding agreements in the final text. Reactions to COP28’s conclusion have been understandably mixed. Going into the talks, the world was more on track to avert catastrophic warming than it would have been without the 2015 Paris Agreement, but a long way from where it needs to be. Even if all the pledges made at COP28 are implemented, the world will still exceed the Paris goal of keeping global warming under 1.5 degrees Celsius (2.7 Fahrenheit) compared to preindustrial temperatures....

Heat pumps can be used to both cool and heat homes. The 2022 federal Inflation Reduction Act provides financial incentives for installing one. SciLine interviewed Theresa Pistochini of the Energy Efficiency Institute and Western Cooling Efficiency Center at the University of California, Davis. She describes how home heat pumps work; how switching to a heat pump reduces your home’s environmental impact; and when to upgrade your heating, ventilation and air conditioning systems. Theresa Pistochini discusses how home heat pumps affect indoor air quality. Below are some highlights from the discussion. Answers have been edited for brevity and clarity. What is a home heat pump, and how does it work? Theresa Pistochini: This decades-old technology is similar to an air conditioner, but a home heat pump also contains a reversing valve that switches the direction the refrigerant flows when you want heating instead of air conditioning. In hea...

Generative AI is the hot new technology behind chatbots and image generators. But how hot is it making the planet? As an AI researcher, I often worry about the energy costs of building artificial intelligence models. The more powerful the AI, the more energy it takes. What does the emergence of increasingly more powerful generative AI models mean for society’s future carbon footprint? “Generative” refers to the ability of an AI algorithm to produce complex data. The alternative is “discriminative” AI, which chooses between a fixed number of options and produces just a single number. An example of a discriminative output is choosing whether to approve a loan application. Generative AI can create much more complex outputs, such as a sentence, a paragraph, an image or even a short video. It has long been used in applications like smart speakers to generate audio responses, or in autocomplete to suggest a search query. However, it only recently gained...

Texans like to think of their state as the energy capital of the world. But in mid-February 2021, the energy state ran short of energy. An intense winter weather outbreak, informally dubbed Winter Storm Uri by the Weather Channel, swept across the U.S., bringing snow, sleet, freezing rain and frigid temperatures. Texas was hit especially hard, with all 254 counties under a winter storm warning at the same time. Across the state, sustained arctic temperatures froze power plants and fuel supplies, while energy demand for home heating climbed to all-time highs. Cascading failures in the electric power and natural gas sectors left millions of people in the dark for days. At least 246 people died, possibly many more, and economic damage estimates damages reached US$130 billion. Water systems, which require energy for pumping and treatment, also were severely damaged. At least 10 million people were under boil-water notices during and after the storm, sometimes for weeks. Low-incom...