In Numerical investigation of the convection heat transfer driven by airflows in underground tunnels (Sci-Hub mirror), a group of engineers from L'Ecole Polytechnique Fédérale de Lausanne and the Swiss Federal Institute of Technology propose that low-cost heat-exchangers placed in subway tunnels could be used to heat and cool homes essentially for free (the system would last 50-100 years, and the pumps would need replacing every 25 years).
The system would pump water or another heat-exchange medium through pipes in the subway tunnels, scavenging the underground cool in the summer and the trapped exhaust heat in the winter, then transfer the heat or cold to nearby residences, businesses and offices for efficient heating and cooling.
The research stems from the incredibly appropriately named co-author Margaux Peltier's Master's thesis; Peltier calculates that installing heat exchangers in just half of one of Lausanne's subway lines could provide heating and cooling for 800 apartments.
As Treehugger's Lloyd Alter points out, the work illustrates how important well-planned, high-density cities are mitigating climate change: high density systems allow for waste from one process to flow into another process as its input; to say nothing of the carbon benefits of building cities where the primary mode of transport is efficient subway trains rather than private automobiles.
Numerical investigation of the convection heat transfer driven by airflows in underground tunnels (Sci-Hub mirror) [Margaux Peltier, Alessandro F. Rotta Loria, Loïc Lepage, Etienne Garin and Lyesse Laloui/Applied Thermal Engineering]
Engineering heat out of metro tunnels [L'Ecole Polytechnique Fédérale de Lausanne (EPFL)]
Energy from subway tunnels could heat and cool thousands of homes [Lloyd Alter/Treehugger]
(via Naked Capitalism)
(Image: MS / EPFL 2019)
Writing in The Journal of Health Economics, three economists claim (Sci Hub mirror) that "a one standard deviation reduction in daily stock market returns is associated with a 0.6% increase in fatal car accidents that happen after the stock market opening" and that this is robust across "a battery of falsification tests."
The latest installment of the always-delightful McMansion Hell (previously) departs from the usual format of mercilessly skewering the tasteless custom homes of the contemporary super-rich and instead delves into their historic precedent, the 1970s-vintage "proto-McMansion," AKA the "Styled Ranch."
For decades, the "bystander effect" (previously) has been a bedrock of received psychological wisdom: "individuals are less likely to offer help to a victim when other people are present; the greater the number of bystanders, the less likely it is that one of them will help."
Back in the 50s and 60s, it was no big deal in most areas to make a call to your local liquor store and have beer, wine and spirits delivered right to your house with little to no restriction. However, that ease and simplicity certainly isn’t in place today. Alcohol delivery laws in 2020 are […]
Unless you’re a regular cannabis user, you might be surprised to learn that the plant itself is basically just that — a plant. It’s not until you put cannabis under high heat that the process of decarboxylation breaks down that raw form into the psychoactive compounds that can actually benefit the body. This unlocking process […]
With our smartphones serving as the vital tether that links us to the rest of our lives, it’s no wonder how low batteries and power emergencies can occasionally feel like a life-and-death situation. I mean, it’s usually not, of course…but darned if it doesn’t feel that way when your indicator is showing only 5 percent […]