With mirrors, the maximum power is whatever sunlight hits the area of the mirror. Which for these satellites is 324 square meters. With solar irradiance at 1361 W/m^2 , that’s only 440 kW of energy, probably spread over a very large area, and not all of the spectrum useful for whatever you might want to use it for.

It’s an unbelievably stupid idea, but that also swings the other way in that it would be highly ineffective for any nefarious purpose, and will probably run out of money before it scales up to where each annoying satellite really does damage to visibility in the nigh sky or anything like that.

Looking around at some websites of companies that sell solar panels, the average expected amount from a stationary solar panel seems to be about 6 Wh per watt of solar panel capacity, per day. At 1.1 kW, that’s about 6.6 kWh per day. And at 3.5 miles (5.6 km) per kWh, you’re only looking at about 23 miles (37 km) per day, if you’re also not driving in the middle of the day, and can actually offload the energy from the solar system battery to the actual car battery.

You’re probably better off trying to charge a regular solar generator with about 6 kWh of storage and 1 kW of stationary solar panels, and just charging your car every night with that. Looking around at the leading brands of solar generators available in the US, that looks like it would cost about $3000-3500, significantly cheaper than this thing.

I just priced it out for a solar generator:

Generator with 2kWh of storage capacity: $899

200W solar panels: $379 each

As far as I can tell, that means I can get basically the same capacity for $2800, just over half the price of this gosun product. There are different pros and cons but I’m not seeing the value proposition here.

Sodium and water is… kind of spectacular:

But sodium ions and water are something we deal with on a daily basis, when we salt food. The characteristics of elemental sodium, as a metal, are basically irrelevant to discussing its safety as ions or bonded in molecules.

I’m hopeful it will be good for aviation. It’s pretty hard to compete with kerosene’s 46.2 MJ/kg. The best batteries today are around 300 Wh/kg in commercial use, and some labs have hit 700+ Wh/kg. But with a MJ being equal to 278 Wh, we’re still talking 20-50x the energy density by weight. And that’s before even talking about how chemical fuels that are burned off leave less weight behind for the remaining vehicle, whereas a discharged battery weighs pretty much the same as a fully charged battery.

Also, if we do move to storing energy in chemical bonds, pulling carbon out of the air, that basically turns into a carbon sequestration technique with whatever excess solar/wind energy we end up with, especially if we intentionally overbuild the capacity for non-peak production, and leave a method for using that energy during peak periods.

I don’t think anyone claims that these synthetic fuels use less energy to produce than other storage mechanisms. This is just a way to store energy in a way that is very dense, measured by both mass and volume.

The “crossover” SUVs are basically station wagons with similar length and width as typical sedans, with slightly more height that tends to be extended back to the rear passengers and a hatch-style rear gate for lots more “trunk” room that is also sometimes accessible from the passenger compartment. When they’re parked next to each other, sedans and crossover SUVs are basically the same size.

I’ll never buy a Tesla but it is still worth noting that their Model 3 still sells well, and is an affordable sedan. Other manufacturers should be competing for that particular segment of the market, and I’d expect Toyota especially to make a move at a more affordable version of an EV sedan if their Lexus ES EV ends up being successful.

It’s worth pointing out that Hainan is an island, which makes its own unique logistical and geographical traits for planning a transition to 100% EV. Bolstering its electricity infrastructure (including less reliance on connections from the mainland) has its challenges but also comes with the tradeoff of relying less on fossil fuels being shipped in.

Also, its low latitude, as a tropical island, makes for more productive solar installations than a lot of other places. So that should help.

Yeah, Honda is in a completely different boat than even Toyota. At least Toyota went all in on hybridization for decades now, where about half of their vehicles sold in North America have some sort of electrification, including some plug-in hybrids and full BEVs. Even though most of those are regular hybrids entirely powered by gasoline (and where electric charging only comes from regenerative braking), that’s a robust global supply chain of batteries and electric motors that they’ve locked down, including for maintenance of the existing fleet, and can easily shift towards increasing pure BEV production (which it seems like they’re doing).

Honda seems to have no plan for the future and can’t seem to pivot. They’re only at about 25% hybrid sales and don’t have their own EV models even in the pipeline. Their core brand identity is lost.

Yeah, we have plenty of materials that can withstand 1g of consistent force, because that’s the default on Earth’s surface and the conditions that we’ve most studied for material properties.

Worth pointing out that Volvo Trucks is a separate company that sold off the previously associated Volvo car brand (initially to Ford). The car company is now owned by Geely too, but still headquartered in Sweden. So the Polestar joint venture is basically a joint venture between two Geely companies.

The truck company is still mostly European owned, although confusingly, Geely also owns about 4.4% of that company, too.

So the operations are separate, and the ownership is separate, too. What Volvo cars are doing isn’t exactly related to what Volvo trucks are doing.

The 2009 bailouts weren’t of the companies or their management. Shareholders were wiped out, and the internal divisions were sold off for parts (somewhat famously, GMAC, the financing arm of GM, became independent as Ally Bank).

The bailouts were to make the newly reorganized entities actually make good on warranties with customers and the collective bargaining agreements with their workers.

That’s how bailouts are supposed to work. Save the other side of the transaction from the failures of the deadbeat company, and then wipe out the actual owners.

Just think about it in terms of the number of people and number of days per year where they need to raise the indoor temperature by a certain amount, compared to the number of people and days needing to lower the temperature.

If you’re looking at a place where it’s 95°F during the day and 85°F at night, and you like to set the temperature to 75°F, you’re only cooling it 10-20°F by time of day.

But if you’re looking at a place where it’s 35°F during the day and 15°F at night, and you want to heat things up to 65°F, you’ve gotta change the temperature by 30-50°F throughout the day.

Even when you’re comparing absurdly hot weather to absurdly cold weather, you’re still comparing something like 110°F to 0°F. You’re still looking at a 70°F swing versus a 35°F swing towards comfort.

Throw in the fact that combustion of fuels (fossil fuels like heating oil or natural gas, or other fuels like wood in a fireplace) is usually only about 1/3 or 1/4 as energy efficient than the equivalent temperature change by heat pump, and you can see how much more energy intensive the typical indoor heating setup is compared to the typical indoor cooling setup.

Some of it is obscured by the fact that fossil fuels are much cheaper per unit energy than electricity from the grid, so that heating bills aren’t as expensive in the same ratio, but in terms of actual energy used, it’s a big difference.

where @[email protected] spent what was probably a lot of time crafting a thoughtful and intuitive explanation for all the actual, tangible reasons why in all their nuance

Only 5 minutes to write the comment, but 20 years obsessing over this shit so that it’s ready to go when people ask.

There are a few different reasons why.

• The US already built up its rail network around low speed trains. Those tracks aren’t suitable for high speed operations, and can’t be modified easily for high speed operations. It’s not just the tracks themselves, it’s the actual paths and bridges and road crossings. If a turn is too sharp, it can’t be taken at high speeds, and the actual curves in the path didn’t anticipate that one day trains would be fast enough to need more gradual turns. So any new rail would have to buy up the land rights with any new pathway, and that is going to be inherently expensive in the corridors dense enough to where there might be demand for passenger rail.
• Rail crossings have to be designed for high speed rail, as well. There are safety and congestion concerns, so many high speed rail projects are required to build more grade separated crossings (bridges and tunnels), which significantly increases construction costs.
• Rail has to compete with air travel and highway travel, in a country rich enough to have lots of people who can afford to fly, and where car-based highway systems are convenient and cheap. Basically, there’s a sweet spot of around 200-400 miles (300-600 km) between cities where it’s far enough that a car is inconvenient and close enough to where trains are competitive with buses or airplanes.
• Along those lines, the US actually has pretty cheap intercity buses that use the existing highways.
• Unfortunately, the city pairs that would have the highest intercity passenger demand also tend to pass through a lot of other cities. If you’re going from DC to New York, the most popular rail line in America, you’ll pass through Baltimore, Wilmington, Philadelphia, and Trenton, each with their own powerful politicians who would push to make sure the train actually stops for them. This is part of why the Acela, our fastest passenger train, takes 190 minutes to travel 226 miles between DC and New York, averaging only 70 mph (115 km/h) despite being capable of reaching top speeds of 160 mph (255 km/h).
• Most rail in the United States is owned by freight/cargo train lines. The passenger network has to lease spots and is lower priority than freight. This leads to scheduling issues, including unscheduled delays.
• Americans are just really bad at constructing big public works projects. Our dams, bridges, tall buildings, rail, highways, roads, power plants, and all sorts of other big projects are almost always behind schedule and over budget.
• The less populated areas where it’s cheaper to acquire land rights also tend to be more environmentally pristine, which means there are environmental concerns around projects like these. In our political system, Republicans are much more likely to ignore those environmental concerns, but they use that political clout to build highways and oil pipelines, not passenger rail. Advocates for passenger rail tend to also be more environmentally conscious, so the environmental concerns do tend to slow down any proposed rail project.

There is high speed rail called Brightline in Florida between Miami and Orlando, with the longest segment operating at 125 mph (200 km/h), and some of the more populous segments operating at 110 mph/180 km/h or 80 mph/130 km/h. It tries to manage those tradeoffs on all new track dedicated to it. But the company is struggling to make money.

There’s a whole saga in California in that the proposed high speed rail project is decades behind and still bogged down, and has examples of all of these problems. The route it takes to connect the two largest cities on the coast (Los Angeles and San Francisco) goes through the inland central valley, to service a bunch of other cities in between. Bizarrely, phase 1 of the project will only serve the relatively low density, low population cities in the Central Valley, without connecting either San Francisco or Los Angeles. Some segments are to share rail usage with lower speed trains, complicating scheduling and risking delays. The environmental debates have slowed things down, as well.

Watch what happens in Texas with its proposed high speed line (bogged down in political infighting), Florida (see above, already built and operational, but facing serious financial concerns about its ability to continue), and California (see above).

I think we’ll eventually see some projects push through, especially if jet fuel gets more expensive than electrical grid power. But for now, America is uniquely hostile to passenger rail, and increasing high speed offerings isn’t necessarily going to induce enough demand for these projects to become economically competitive with other forms of intercity transportation.

Yes, but this published finding is interesting because it reduces the steps.

Anyone can extract the elemental lithium from lithium cells, but it takes a lot of energy and harsh solvents and creates a lot of waste byproducts.

But extracting lithium iron phosphate (LFP) salts is much less energy intensive, if those salts can be reused. This paper shows that LFP can be extracted and then reused as an ingredient in creating LMFP, a cathode material with higher performance characteristics.

This is akin to using a technique to filter water instead of cracking it into hydrogen and oxygen and reconstituting the elements back as water.

Even in the U.S., we use a lot more energy heating homes than cooling homes. Around 43% of our total in-home energy usage is on heating, and about 8% is on cooling.

Heat waves don’t cause nearly as big of a strain on our grid as winter storms, because AC doesn’t consume as much energy as even our efficient heat pumps in the winter.

That’s because a heat pump that can lower the temperature by 10°-15°C is really all you need in the hottest part of the summer, whereas in the winter raising the temperature 25°C isn’t uncommon.

I was flabbergasted the first time I realized just how far north Europe is, compared to North America.

Paris is at 48° 51’ N, significantly further north than Toronto (43° N), Montreal (45° N). London is at 51°N 30’, which is further north than Vancouver (49° N), and just slightly further north than Calgary (51°N).

Even southern European cities like Ibiza (39° N) are at comparable latitudes to northern American cities like Philadelphia (40°N) or even New York (41°N).

If Europe starts seeing climate comparable to similar latitudes in North America, that would represent a huge change from the recorded history.

That’s not true. There is plenty of profit to be made with selling stuff that helps reduce energy use, selling energy that uses less fossil fuel (or produces less CO2), undercutting competition with more efficient methods, etc.

The tech world talks a big game about disruption and making billions or even trillions from it. You don’t think there are people who want to make trillions disrupting fossil energy companies?

The University of York compared panels capable of 1.5 kW and found that vertically mounted bifacial panels generally outperformed tilt mounted monofacial panels, by between 14-27% on a monthly basis, at least when surrounded by gravel, in the climate/altitude of that particular location.

The reason given is that vertically mounted systems capture a lot more indirect reflected sunlight from the surroundings, across a wider range of conditions.