dr_jiang t1_j5t993o wrote on January 25, 2023 at 12:17 PM

Reply to comment by skimish1 in The Key to California’s Survival Is Hidden Underground The state is ping-ponging between severe drought and catastrophic flooding. The solution to both? Making the landscape spongier. by Sariel007

I think you might be overestimating the amount of conventional agriculture going on in Los Angeles.

dr_jiang t1_j1ae117 wrote on December 22, 2022 at 9:05 PM

Reply to TIL that DMVs in the US are allowed to sell some of your personal information and do. This practice is legal under federal law. For example, Florida’s DMV made $77 million and California’s DMV made $52 million in 2017 through this practice alone. by TheKeyboardKid

It's a major part of business for third-party auto retailers (AutoZone, e.g.). They use the aggregate data on car ownership to determine which stores need to carry which parts in inventory based on the make, model, and age of cars in that sales region.

dr_jiang t1_iyc5ycj wrote on November 30, 2022 at 8:23 AM

Reply to comment by feor1300 in TIL that beans are banned in Spacecraft because they can produce "1-3 cups of flatus" in an environment where there are no windows by April_Spring_1982

Or you could read the article, which talks about this specifically and points out why you're wrong.

dr_jiang t1_iy5ip33 wrote on November 28, 2022 at 10:14 PM

Reply to comment by Nyrin in 'Landmark achievement': Rolls-Royce and easyJet hail successful hydrogen jet engine test by Wagamaga

I'd forgotten about the "need gas to haul gas" math. Honestly, I stopped taking hydrogen as aviation fuel seriously when the white papers came in describing the plane passenger economics.

The reference escapes me, but the bottom line was that converting existing airframes to hydrogen meant ripping out 14-20% of seats and paying 60% higher fuel costs. Barring science-fiction level advancements in the underlying technologies, commercial air travel as we know it can't exist in a hydrogen-fueled world.

No industry, no government, and no passenger is going to tolerate that.

dr_jiang t1_iy5ar4z wrote on November 28, 2022 at 9:21 PM

Reply to comment by Robot9P in 'Landmark achievement': Rolls-Royce and easyJet hail successful hydrogen jet engine test by Wagamaga

Commercial aviation burned 95 billion gallons of jet fuel in 2019. Hydrogen has one fourth the energy density of jet fuel, and takes 2.4 gallons of water per kilogram of hydrogen if we're making it through electrolysis.

There's plenty of water in the Great Lakes (for now: we're currently turning it saline). There's not plenty of spare electricity to power the electrolysis plants, or plenty of spare money to build them, or plenty of hydrogen transport and storage infrastructure to get it from the Great Lakes to everywhere planes need to take off from.

Hydrogen has plenty of use cases where it makes sense, and its weaknesses as a fuel can be mitigated. Aviation is not one of them.