The Tech Forum

[chaotic neutral observer]

This type of generator is interesting at a theoretical level, but I don't see it being very practical.
The researchers currently report 25 mW/m², and think they can improve to 0.5 W/m².  In comparison, a solar panel can give you 200 W/m².

And, as with solar panels, this technology requires a clear sky. If it is overcast, the sky temperature will be higher, and reduce the available temperature difference. This approach requires the ground to be warmer than the sky to work.

[Brother Mythos]

True, the power generation is not impressive. But, I do find the technology interesting.

This article caught my eye because I remember well the big industrial search, of years ago, for energy to be harvested from waste heat.

[Faust]

Solar Panels require some rare materials. If this is just simple LED diode it could have applications in power scavenging or when doing it over long empty distances like empty highway regions

[chaotic neutral observer]

Solar Panels require some rare materials. If this is just simple LED diode it could have applications in power scavenging or when doing it over long empty distances like empty highway regions

Today, you can get a 25 mW (rated) solar cell that measures under 2 cm² for $2.57 (in quantity).
500 mW brings that up to ~$10.

Even if you consider that the actual power out of these solar cells is likely to be below the rating, I would say the cold sky thermoelectric approach is optimistically a couple of orders of magnitude behind the point where it would be competitive.

RTG's are only viable because there is a huge temperature difference involved.

[altered]

This is ridiculous. I have no idea how it can possibly work. I fucking love it.

[Brother Mythos]

"Lockheed Martin Selected to Develop Nuclear-Powered Spacecraft"

As per the article:

"Lockheed Martin [NYSE: LMT] has won a contract from the Defense Advanced Research Projects Agency (DARPA) to develop and demonstrate a nuclear-powered spacecraft under a project called Demonstration Rocket for Agile Cislunar Operations (DRACO). The project will represent a rapid advancement in propulsion technology to benefit exploration and national defense.

DARPA partnered with NASA's Space Technology Mission Directorate on the DRACO project, as both agencies will benefit from this leading edge technology. The in-space flight demonstration of a nuclear thermal rocket engine vehicle will take place no later than 2027."

Faster, Farther, More Agile
Chemical propulsion engines have long been the standard for spaceflight, but for humans to travel to Mars, they will need much more powerful and efficient propulsion. Nuclear thermal propulsion (NTP) engines offer thrust as high as conventional chemical propulsion with two-to-five times higher efficiency, which means the spacecraft can travel faster and farther and can significantly reduce propellant needs. They also enable abort scenarios on journeys to Mars that are not possible with chemical propulsion systems."

I haven't hear much about NTP in recent years. So, it will be interesting to see the rocket engine this R&D project manages to build.

Here's the link:   https://news.lockheedmartin.com/2023-07-26-Lockheed-Martin-Selected-to-Develop-Nuclear-Powered-Spacecraft

[Brother Mythos]

"Old EV Batteries Get a Second Life Storing Solar Energy"

"We're at a point where we really can scale this."

As per the article:

"To make renewable energy from intermittent sources like solar and wind available when it is most needed, it’s becoming more common to use batteries to store the power as it’s generated and transmit it later. But one thing about the Cuyama facility, which began operations this week, is less common: The batteries sending energy to the grid once powered electric vehicles."

And, further along in the article:

"The facilities are meant to prove the feasibility of giving EV batteries a second life as stationary storage before they are recycled. Doing so could increase the sustainability of the technology’s supply chain and reduce the need to mine critical minerals, while providing a cheaper way of building out grid-scale storage.

“This is what’s needed at massive scale,” said Freeman Hall, CEO of the Los Angeles-based large-scale storage system company."

This sounds like a potential win-win reuse of old tech hardware to me.

Here's the link:   Second Life for Old EV Batteries

[Brother Mythos]

"New technology installed beneath Detroit street can charge electric vehicles as they drive"

As per the article:

"Crews have installed what's billed as the nation's first wireless-charging public roadway for electric vehicles beneath a street just west of downtown Detroit.

Copper inductive charging coils allow vehicles equipped with receivers to charge up their batteries while driving, idling or parking above the coils.

The quarter-mile segment of 14th Street will be used to test and perfect the technology ahead of making it available to the public within a few years, according to the Michigan Department of Transportation."

There have to be convenient ways for EV owners who don't have garages, private driveways, or private parking spaces to charge their vehicles. I believe this technology will make owning and driving an EV a lot more practical for most people. It also opens up the possibility of places like drive-thru restaurants, to install wireless-charging. Other businesses with parking lots could benefit as well, as it eliminates the need for their customers to have do deal with charging cables.   

Here's the link:   Electric Vehicles Charged While Driven

[Brother Mythos]

"First plasma fired up at world's largest fusion reactor"

"Japan’s JT-60SA tokamak will test technologies put to use in ITER"

As per the article:

"The long trek toward practical fusion energy passed a milestone last week when the world’s newest and largest fusion reactor fired up. Japan’s JT-60SA uses magnetic fields from superconducting coils to contain a blazingly hot cloud of ionized gas, or plasma, within a doughnut-shaped vacuum vessel, in hope of coaxing hydrogen nuclei to fuse and release energy. The four-story-high machine is designed to hold a plasma heated to 200 million degrees Celsius for about 100 seconds, far longer than previous large tokamaks."

And, as per the end of the article:

"By 2050, Japan also hopes to build DEMO, a proposed demonstration power plant that would provide a stepping stone from the research of JT-60SA and ITER to commercial fusion power. Shirai says he is well aware of the competition from alternative approaches to fusion energy, fueled by an influx of private money into the field. But with competition comes opportunities for collaborations among those with new ideas. “Having many people coming into this area is a very good thing,” Shirai says." 

Developing fusion power has been a long slog. But, it appears that some progress is being made.

Here's the link:   First Plasma at World's Largest Fusion Reactor