Safety features can be present if the manufacturer bothers. The only safety feature that’s not allowed in that class is large amounts of mass.

Airbags and seatbelts don’t add any appreciable mass. A protective cage around the passenger doesn’t add much either. Space (to prevent hitting things with your head in an accident) does introduce a mass penalty. Many microcars lack a safe amount of head space which sure annoys me.

Automatic braking (a lidar and some actuators) would not add much. If a vehicle happens to have 4 independent motors, then traction control is a software problem with zero mass. Individual control of brakes would admittedly add mass - separate brake pumps for each wheel.

The frame of an L7e can be made pretty sturdy. Some folks have been asking me if I’m building a tank, but no, it’s an L7e - instead of armor, it’s covered in greenhouse plastic. :) It’s the beams that count, I don’t care if anyone punches through the gaps. :)

Tiny picture because I like to keep some privacy.

This question needs a clarification: what is the definition of “highway” in your country?

Here in Estonia, I can go on highway with a farm tractor, I’m just obligated to pull aside if a column forms behind me. Meanwhile, for example in Germany, going to an Autobahn with a farm tractor would quickly attract fines for a traffic violation.

I’ve driven on a highway with a large L2e trike (rated speed 45, actual capability 55) but did not feel comfortable there. I do feel comfortable on a highway with a Mitsubishi i-MIEV (crappy e-car, do not buy), typically driving at 80 km/h. It has a motor of 37 kW (if I remember correctly) but cruises decently enough at 9 kW of power, so a lighter car would come to highway speeds with 11 kW for sure (if well built).

I would feel comfortable on a highway with an L7e cargo quad (for which I hope to get a rated speed of 70, but that remains to be seen when it’s completed), and the one I’m building has 4 x 3 = 12 kW power.

A customer of mine sells electric road maintenance vehicles, but they are type certified in the N class.

I would advise googling for “L6e”, “L7e”, “electric car”, or maybe “electric vehicle”. In my search, various Chinese products come up, but I notice that many aren’t type certified in the EU, so be very careful. You want to avoid doing type approval on your own. Also, consider if you can get spare parts in the future. Find a product with local support.

A big advantage of its sodium cells is also the fact that they can retain more than 92% of their capacity even when operating at -20°C (-4 Fahrenheit) and discharging at those freezing temps.

That is very promising to hear. My current vehicle, which uses first-generation lithium batteries (made on 2011), loses almost half of its range at that temperature, and that is before heating.

For me and my habits, these have been working for a few years. They cost me about 75 €. But as always, product portfolios change and most likely they’re out of production. And maybe they’ll break this year, making my recommendation premature - but I see no signs of breaking yet.

Why I picked them: they had a rubber lower part and a string-tightened but closed upper part made of fabric (no “tongue” with open sides, no zipper, zippers can break down). My access way gets flooded often, and most of the flooding occurs during cold weather. So I often walk in snow that has ice and water underneath, and break it when walking. I could use rubber boots, but then it would be cold.

Nice to know. :)

Reading tip: a comment from a reader John Beech (an old radio amateur) at the bottom is probably of greater practical value: he describes how he developed DIY cells to the point of running a 2 W radio.

Another way to build DIY batteries is using the iron-air chemical combination. A decent collection of recipes can be found here, using filter cartridges of activated carbon as cathodes and rebar wrapped in steel wool as anodes:

https://www.instructables.com/Create-large-refuelable-metal-air-battery/

These cells convert iron into rust at an accelerated pace, producing power while doing that. However, they have really low cell voltages, so you have to wire many cells in series or use a really efficient voltage converter. Aluminum gives high cell voltages, but on the downside, produces annoying waste chemicals.

Pigs are intelligent and curious creatures, so it’s possible that they would learn this.

However, they might come looking at a ground ambush FPV for other reasons too - most FPV controllers slowly spin their motors when armed, or beep (resonate their motors) to indicate that they’re armed. This could draw attention - pigs might think that a piglet is in trouble and come looking. Hopefully not touching, because on that screenshot, the warhead is also waiting to be touched.

But the killed-to-wounded ratio (as well as the overall loss ratio) is probably very bad for Russians:

• if a front moves slowly, leaving devastated land behind it, those who come across that land, they won’t have infrastructure supporting them
• Ukrainians do not seem hell bent on crawling slowly across devastated land, they either defend or do maneuver warfare… Russians seem to have different priorities, they attack even when the attack is very costly
• these days, any vehicle is a target for FPV drones and must be equipped with powerful electronic countermeasures (which also announce its presence) to survive
• but some FPV drones lock onto targets with machine vision and others are piloted over optical cable, and there’s not much hope against these even with jammers
• so, approximately within 7 km of the front, vehicles are a risky thing to have
• evacuating a wounded person to a distance of 7 km to get him on a vehicle requires non-trivial effort
• if the official tactic is making “meat attacks”, it’s hard to imagine where that effort comes from

So, that effort probably doesn’t happen.

I know of a company in Ukraine making remote operated ground vehicles (“stretcher on tracks”) that can be used to evacuate a person even if they cannot steer the vehicle, but even Ukrainians have few such tools. Russians probably aren’t bothering.

Ah, sorry, I was careless with terminology.

Throughout my post, I was thinking of rigid-envelope airships, but at some point, referred to them as blimps. Apologies.

About the only role I would give to a non-rigid airship is “a tethered observation post”. :)

Some guesses, in declining order of probability. :)

• Vanity and spite. After all, he’s not emotionally mature.

• With some probability, rational attention-seeking to keep his supporters entertained and lobbyists (who bought and propagandized his way to power) satisfied. He has to deliver them goods. This is how he shows that he intends to deliver the goods… that he actually cannot deliver without changing the constitutional order very much. You can mark my words: lots of wind parks will be opened under the Trump administration, despite anything he does.

• Maybe he wants to test the mettle of the terrible Renewable Industries Complex - an industry very prone to organizing coups and hiring assassins. If I were him, I’d consider twice, all the people in the solar business that I know have been extremely menacing. ;P

Hydrogen is a nuisance of a gas, though - it has a very wide combustible range of mixtures.

But an airship envelope containing multiple lifting units of hydrogen could be passivated by filling the envelope with a non-combustible gas like helium.

So, there’s a big sausage providing structure and that’s full of helium (or nitrogen, or CO2, or anything else which doesn’t react with hydrogen in normal conditions)… and it contains balloons full of hydrogen. If one of them springs a leak, the leak won’t be going into an environment that supports fire. And if the leak then proceeds into surrounding air, the hydrogen is hopefully diluted beyond its combustible range.

Considerably less expensive than using helium only. But considerably safer than using hydrogen among air.

Part of the safety focus is from sticking so many people in the same fuselage - which, being big, has no individual rescue equipment and cannot be brought down by parachute either - so nothing critical is allowed to fail.

Side note: that’s not the only possible model, however - one can also design heavier than air craft that are smaller, almost passively safe (falling controllably without power, at somewhat above parachute speed), and design small aircraft that have rescue systems (parachutes which can land the whole aircraft).

Size itself is then a function of economic realities (air travel has undergone explosive growth).

Blimps would have to somehow fit in. Having considerable air resistance, blimps cannot travel as fast. Being unable to travel as fast, they would fall behind at moving X people per hour - while a blimp makes one roundtrip, a jet aircraft would make multiple roundtrips.

If however a jet aircraft is deemed environmentally unsustainable on account of fuel use - then the milestone to compare a blimp against will be a propeller-electric aircraft. Which is more limited in speed, requires charging time, is more limited in range - and therefore makes less roundtrips in an unit of time.

From one viewpoint then, the success of airships thus depends on whether fast aircraft can reduce their environmental footprint. If they can, blimps will not be widespread. If they cannot, blimps might become widespread.

Overall, a fast airplane is effective at getting results (transporting people) but not necessarily efficient at doing that. There is perhaps only one aspect where a high-powered aircraft is more efficient… use of space. But space is not a scarce resource in the atmosphere. Only on the runway.

Out of the previous considerations, I come to the conclusion: blimps probably won’t replace airplanes. Especially for longer trips, having to wait less is what makes people prefer speedier travel. Blimps cannot provide that. However, airships might carve out a niche for servicing shorter routes and local traffic.

Looking at the installation, I would advise the experimenter to immediately remove the hub motor from its semi-submerged state (thermal variation of the environment will pull in water through seals and bearings) and use a shaft (or belt) of reasonable length to extract power.

Besides that, nice project.

…and for those who prefer their information as text anyway, here’s an article on a very overlapping topic, which likely gives the same information as the video:

Geothermal Energy with Millimeter Wave or Direct Energy Drilling

The problem:

Multiple countries, over decades, have tried to drill into the Earth’s crust to reach the mantle without success due to exceedingly hot temperatures in deep bore holes and extremely hard rock formations located under pressure deep underground. From 1961 to 1966, the United States’ Project Mohole tried to drill through the crust out in the Pacific Ocean off of the coast of Mexico. They were only able to reach a depth of 601 ft (183 m) in 11,700 ft (3,600 m) of water. Between 1970 and 1992, Russia’s Kola Superdeep Borehole Project (see Figure 3) reached a record depth of 40, 230 ft (12.2 km) but were only able to drill about a third of the way through the Earth’s crust. In 1990, Germany initiated the German Continental Deep Drilling Program in Bavaria to try to break Russia’s record but were only able to drill to a depth of 5.6 miles (9 km).

Today, boreholes of 7 km are probably reliably attainable with state-of-the-art equipment. This can be very expensive and in most places, ground temperature at 7 km is not sufficient to warrant going there for energy.

The proposed solution: drilling boreholes with a maser (radio frequency laser in the millimeter wave spectrum). The gyrotron would likely sit on surface while the waveguide (antenna) is lowered into ground. Meanwhile, vapours would be blown out with compressed air (or maybe nitrogen, if things keep catching fire).

If the company developing it gets the system to work, boreholes deep enough to reach good quality heat would be possible everywhere on Earth, not just handful of places.

It makes good sense in theory, and I hope they get it working. But its benefits won’t reach many people for at least a decade or two, so while the folks at Quaise Energy do their thing, I suggest that everyone else continue installing renewables and storage. :)

A sort of self-excited active cooling, yes.

There are large-scale devices where gas starts vibrating when you add heat. The best known from physics lab experiments is the Rijke tube and the oldest is probably the “Kibitsu no kama” (a rice cooker of specific proportions which was used by monks in Japan for fortune-telling). These produce considerable quantities of audible sound, and they are fun toys…

…but in this case, the spontaneous oscillation of coolant at a microscale seems to speed up heat transfer magnificently. Not just fun, but very practical. A great number of tiny heat engines, with no moving parts but the working fluid, with the goal of transfering heat away from its source.

It seems that weather patterns lasting longer is part of the new climate pattern.

Were electric ferries not a viable option?

For short routes, they are.

Here in Estonia, two ferries that sail to the island Saaremaa (route Kuivastu-Virtsu, about 4 nautical miles so really short) …they typically charge in port and travel on battery power. They have a combustion engine of course, and can use it when ice is thick (which lately hasn’t been the case, and this year is ridiculous, it’s January soon and there even no snow, not to speak of sea ice).

https://news.err.ee/1609198900/40-million-procurement-underway-for-larger-electric-vessel-to-serve-saaremaa

The power grid connection at the port was redesigned of course. Charging a ship requires more amps than an ordinary port might have access to.

But how long is the Arran sea route? Sources give me different numbers and on the map, I can’t figure out which port they actually prefer to sail from. Either way, it looks manageable on battery power.

Here is the Mauna Loa data line from 1958, matching the top figure.

https://upload.wikimedia.org/wikipedia/commons/c/c5/Mauna_Loa_CO2_monthly_mean_concentration.svg

The rest has been matched and synchronized to it using other sources. I’m not a climate scientist, but I would guess the best sources are ice samples from polar regions where it accumulates from top and melts from bottom. CO2 dissolves in water and when snow falls and turns into permanent ice in such places, it captures a snapshot of that period’s atmospheric gas content, among that the CO2 level.

Sadly, Rojava is incredibly land-locked. It is possible to deliver assistance in various forms (from woolen socks and SDR cards to items one won’t mention on the net) to folks who defend Ukraine… but I don’t know a single organization except Heyva Sor (Red Crescent, humanitarian and medical assistance) that reaches North-Eastern Syria (even Heyva Sor is better than nothing, for all I know they depend on imported antibiotics).

If anyone knows of channels that can get assistance to those people, clues would be welcome.

I hope the HTS and SNA don’t have overlapping interests and listen to different people. They might hold each other in check, at least for a while, and thus prevent restarting of the civil war.

I hope the folks in North-Eastern Syria get a tolerable (or even favourable) political solution - some kind of extended autonomy within Syria.

But the wider context is Erdogan waiting for Trump to make deals with him (and also Israel seems to be trying to ruin its relations with any new government of Syria pre-emptively) - so if I were them, I’d keep drone batteries charged. They have a snowball’s chance in hell.

They start up reliably, but have considerably less range in cold. Heating is a big issue for many models, but some are well equipped. It typically starts up faster, but drains the battery considerably - unless a heat pump has been used.

As for my EV (a Mitsubishi MIEV - don’t get one unless it’s for free) - it doesn’t even start reliably. :) It has 3 steel wires running from the “gear stick”, one to actually switch “gears” (most of which are motor controller modes, only the parking position is mechanical, so an electrical switch would suffice) and 2 to prevent the user from accidentally starting the car without the brake pressed and stick in parking position. The mechanical wires going to the brake pedal and ignition lock are U-shaped, so water gathers inside. Once weather drops under -15 C, they freeze with high enough certainty, preventing the “gear stick” from being moved out of P without violence or heating (hint: there is no heating in the car capable of achieving this goal). This winter, I should finally dig into the mechanism and neutralize it forever.

A note on the “Fatal accident rate” topic:

A car which uses touch panels for control and electronics for simple things like doors, and relies only on a camera to do self-driving (no lidar), is bound to be unsafe in multiple ways. Drivers make more mistakes because they aren’t provided physical switches and levers, they make mistakes because they’re distracted by light from screens, in emergencies there are issues with unlocking doors and finally, when machine vision fails, there is no backup to tell of a Big Old Obstacle right ahead.

A note on the “Spying” topic:

Mozilla compared privacy policies. They didn’t actually take apart cars, intercept their comms or dissect manufacturers’ apps. I wish there existed a review of actual behaviours, as opposed to policies.

A car’s ability to actually spy on the user depends on its tech, not just the policy. So a very simple car (not a Tesla, obviously) with a very agressive policy of “we collect everything” would be safer than a smartphone on wheels with a modest policy. You can’t spy if you haven’t got sensors.

Nice to know that they can also extract it from seawater. :) Sodium is already (more) available in that way.