Soylent Green?

I've read the articles, and I've gotten very close to installing home solar. Every article I've ever read says the same thing, which is that you try to get close to your average home power consumption. You don't size it massively larger. Because the power companies in California don't pay you if you produce too much power, and running up huge bill credits won't help if you don't eventually use that extra power.

And the folks storing extra power for backup aren't going to opt in to this sort of scheme anyway, because they won't want their batteries to be dead when they need them most.

Either way, even if you convince the people who overbuild the battery for backup purposes to sign up, none of what I said is wrong. Please, please tell me what I'm missing, because I *do* understand this VERY WELL, and I still don't see any plausible universe in which this isn't effectively just a storing energy with the same greenness as the grid except on days when dumping the extra power late in the day is immediately followed by a day in which the power from the solar panels would otherwise have been curtailed (which is the only situation in which that solar power wasn't already being used to make the grid greener).

The basic argument is that by not turning on a peaker plant, you're making the grid greener, but that falls flat when you realize that unless solar or wind power would be actively curtailed when you recharge the battery the extra time, that power used for recharging would not otherwise have been needed, and it has to come from somewhere, and if wind and solar aren't being curtailed, it comes from keeping some other kind of power plant online — natural gas in all likelihood.

It's a classic example of greenwashing. I'm sorry to be the bearer of bad news, but there's no such thing as a free lunch here.

Batteries shift load, period; except when curtailment is involved, they do not make the grid greener. Period. Batteries plus extra solar panels can make the grid greener, but the solar panels are what makes the grid greener. The batteries just allow you to spread the greenness over a longer period of time. And yes, when you have so much excess solar that you get curtailment, batteries are needed for some of that solar to make a difference, but that's the *only* time batteries make the grid greener, period.

First, people probably won't ever live an average of 100 years. Second, you don't need a stable demographic profile. There's exactly no advantage to having elderly people onboard initially, for a number of reasons:

• Food production probably won't be able to be at full speed on day one unless you start the process long before you take off.
• Older people are less able to learn the new skills that they would need to be able to do repairs on the ship, etc., and are less likely to already know those skills.
• Older people are less able to do physical labor than younger people, and will therefore be more limited in their ability to contribute.
• Older people have fewer years to contribute before they stop being able to do so entirely and become a burden on the ship's limited resources.

I mean, if you want to all but guarantee that the younger folks turn sociopathic and throw the elderly out the nearest airlock on their 50th birthdays, a great way to start that story is by creating the generational ship with people of every age from day one, so that from the very beginning, they resent the elderly. If you actually want them to retain their humanity, you'll almost certainly want an upper age cutoff on the folks who go up in the initial wave.

And even if you decide that the cutoff should extend beyond child-bearing age, you sure as h*** don't want to bring twenty-four 90-year-olds. Half of them probably wouldn't even make it to orbit, and that's also not an accurate picture of normal demographics. There are fewer and fewer people the older you get, even if you ignore population growth, because some people die before they get to that age.

Over time, you want a fairly even distribution of age, but that will happen on its own. People don't turn 25 and suddenly say, "I want a baby." They have kids at different times, based on what's happening in their lives. Some won't have any kids at all. Some will have kids later in life. That means that the distribution going in doesn't really predict the distribution going out. There's a lot of entropy at work.

It probably does help, however, to have a roughly even percentage of people at each age throughout the age range where people typically have children. You don't want everybody to be 18, and you don't want everybody to be 45. As long as you have roughly the same number of people at each age within roughly the primary procreative band (ostensibly 18 to 60 for men, 18 to 45 for women, so probably pick the narrower of those two bands), you should end up with a fairly consistent rate of childbearing, in all likelihood.

It may also be problematic to not have children on the ship, because you would see a huge dip as though there had been no new children born for 20-ish years, and by definition, that wouldn't smooth out until about twenty years after the original crew dies. There are, of course, ethical questions about whether it is okay to do this, because kids aren't old enough to understand what's happening, and wouldn't really have any say in the matter, so it could also be problematic if you do have children on the ship, just in different ways.

On the other hand, not having any school-aged children for at least the first five years means more time to spend preparing the habitat for future increases in head count, building spare parts out of raw materials, leaning how the ship works, coming up with rules and procedures to ensure that things run smoothly, etc. And the only real disadvantage would be that it would take two decades before you would start having replacement people who are old enough to do useful work, which is probably fine if you cap the age at 45 or so, because by the time they're ready to retire, you'd have the first batch of replacements, and you probably won't lose *that* many people in the first twenty years. So the only big impact you'd expect from not starting with children onboard would be a 20-year-long dip in mortality when the oldest of the original crew reach their typical lifespan.

So really, I'd say that it's critical to be evenly spread across child-bearing ages, and that's probably the only thing that really matters much.

You can't count that power twice. Even if you assume that every drop of power that goes into the batteries comes from the solar panels, you're still taking away power that would otherwise have been sold back onto the grid, which means using some other non-solar power somewhere else that would have otherwise been solar power.

Put another way, before this change, every drop of the power produced by the solar panels (ignoring curtailment, which by definition this can't change, because batteries can't be charged beyond full) was either being used by the household, going out onto the grid to make the grid greener, or charging the batteries for later use to make the grid greener.

To the extent that this charging was already occurring, the shift in utilization of the battery's output means that the power that otherwise would have gone to the household from the solar panels later at night would come from a dirtier grid power source (except to the extent that the household wasn't running down its batteries fully, which while possible, is rare).

To the extent that the charging was in excess of what came from the solar panels, again, that power came from the grid, at grid levels of greenness.

So regardless of whether you're looking at the power that appears to come from the solar panels or the power that comes from the grid in excess of the solar panels' capacity, the power effectively is no greener than the grid, with the sole exception being situations in which *all* of the following are true:

• The customer's battery storage is so massively overbuilt that they typically don't run it down with their own usage before their solar panels start recharging the batteries the next day.
• The customer's solar panel array is sufficiently overbuilt that it can fully recharge the battery in a single day.
• The extra power dumping occurred the evening before a day in which the excess power would have been curtailed.
• The customer's charging software isn't already selling back that excess power at night for arbitrage purposes.

One could reasonably ask why such unicorn customers are paying PG&E for grid-tie operation in the first place — all three or four of them.

You don't take 2400. You take probably more like 800 people of child-bearing age, ideally pre-coupled. You have a two-children-per-family policy, i.e. when the first generation are born, you have about 1600 people. By the time the third generation is born, the first generation are starting to die off. You keep safety margin for the occasional happy accident.

Besides, you have to build everything to handle significantly more people than you plan to have, so that if some piece of equipment fails, everybody doesn't die. That margin should be big enough that you'll never have to worry about such things unless you didn't plan correctly.

Practical, no, but that doesn't necessarily mean it isn't worth considering. The real question is whether there's enough data to determine that it would sustain life, and if not, whether you would have be able to bring along enough fuel to turn around and come back, while still being able to handle any other navigation needs along the way (e.g. avoiding stray asteroids). I don't even have any concept of the fuel requirements for something like that, because there's no way to know what you're going to encounter beyond the expected delta-v requirements.

No, as long as you have adequate redundancy for critical systems, enough hull thickness and steering to avoid collisions with something that can cause too large a hull breach, enough spare compressed air far enough inside the ship to repressurize after fixing minor leaks, and adequate raw materials and tooling to make spare parts to fix things that break, you shouldn't need a large number of ships.

You should probably have at least three ships, though, traveling in parallel at a close distance, with the ability to dock them to one another in case one becomes completely unusable for some reason, so that the other two can divide up the defunct ship's crew among them, and ideally tow the defunct ship alongside while they try to find a way to fix it.

Unless I'm misunderstanding, it depends on only two things:

• The number of kWh drained per season.
• The cost of the battery.

Batteries are a wear item. A Tesla Model X battery costs $15k refurbished, probably more like $30k new. That gives you 1,500 cycles of 100 kWh, or 150,000 kWh. That comes to twenty cents per kWh.

Actual grid-tie batteries like PowerWall are even more expensive. PowerWall 3 comes in at $15,400 for 13.5 kW that will probably last about 4,000 cycles, or 54,000 kWh total. That's 28.52 cents per kWh.

As capacity goes, consumer-sized grid batteries are staggeringly expensive — about as expensive as nuclear, more than twice as expensive as solar, potentially up to 5x as expensive as wind, and up to 7x as expensive as natural gas. You'd have to be absolutely crazy to use batteries as a power source unless you're absolutely desperate.

100,000 homes provided a total of 535 megawatts, or 5.35 kW of power. So for PowerWall users, every hour that this experiment was running cost the homeowner $1.53.

That means after 98 hours (a little over 4 days), the homeowner is getting screwed. Assuming a season is three months, that comes out to 32.6 hours per month, or 64.4 minutes per day. But during this test, they ran it for two hours. If that's the amount that they would typically draw each day, I'm willing to bet that a whole lot of people do the math and turn this off after one season, because they're getting seriously ripped off.

I would actually say that it has significant environmental negatives; they're just the same negatives as the source of the original power to begin with, times a slightly-over-one scaling factor to account for energy conversion losses (AC to DC, electrical to chemical, chemical to electrical, DC to AC). After all, every time one of those batteries gets charged unnecessarily with (statistically speaking) natural gas, that's natural gas that wouldn't have been burned were it not for charging the battery.

No, not really. I give money to a lot of companies whose business practices I don't particularly like. That's the problem with such a small number of companies having such solid control over a market. If you don't do that, you won't have a cell phone, Internet service, electricity, etc.

Arguably I don't anymore. My mom watches it all the time, so she has a real subscription. I just do an add-on plan. When they took away my basic plan by force, I dropped my personal subscription. And I'm positively giddy every time I think about the fact that that their decision to be excessively greedy pushed me into a plan that pays them even less, gives me better picture quality, and is still ad-free.

I get dinged when I haven't signed out my mom's account at my house on the other side of the country, even though I'm an add-on household for that account.

Also, my mom got dinged when she stayed out here for a while, even though obviously she wasn't using her account from back home. She ended up in a state where she couldn't watch Netflix at all until I got home and helped her fix it.

Their algorithm sucks, and is arguably elder abuse for profit's sake. F**k Netflix.

Elemental lithium does, but LiC5H3N2O4 is a salt, and, as I understand it, is not particularly reactive.

My chemistry knowledge is almost nonexistent, so all of this could be wrong, but here's what I think: Mercury is less reactive than lithium, so it won't take its place in a single-replacement reaction. Mercury is insoluble, so no double replacement, either. It's a salt, so no acid-base reaction. So unless a lithium salt somehow catalyzes oxidation of the elemental mercury, I wouldn't expect any reaction.

But again, my chemistry knowledge is almost nonexistent, and this is from my skimming a few Wikipedia articles, so I could be very wrong.

Of course, we're talking about the intersection of chemistry and biology here, so there's always some possibility that some cells in the brain might release some other chemical that reacts with the salt and releases elemental lithium for use by the brain, and that the resulting elemental lithium could the form an amalgam with the mercury and effectively aid in chelating that mercury, but I wouldn't think the odds are all that great.

The odds are way better that it is some fascinating situation where whatever cells are responsible for removing the plaques become less effective without an adequate supply of lithium, and the plaques then end up sequestering the lithium, creating a vicious circle.

And even that is probably less likely than that the sequestration-induced lithium shortage merely exacerbates the mental decline caused by the shortage of properly folded amyloid proteins, and the reduction in plaque in the mouse model has some other root cause related to how they produced Alzheimer's-like symptoms in the mice, in which case this treatment would only slow the progression in humans, rather than reversing it.

Large-scale double-blind human studies are the only way to really know for sure.

My recollection is that the amount of mis-folded amyloid isn't a strong indicator of cognitive function; rather the existence of adequate amounts of properly folded protein is. If you're producing more, then you can have more of the bad stuff and still have enough of the good stuff to feed your neurons, basically. That said, larger amounts of mis-folded amyloid probably increases the rate at which the normal amyloid protein misfolds, assuming this is a prion situation, so there's likely some correlation there, but it still ends up being dependent also on the rate of production.

How lithium fits into that framework, I can't imagine, unless maybe lithium is somehow both required for the machinery to clear out the plaque and being sequestered by the plaque.

Wait a minute. I just noticed something in the abstract that I missed on the first reading. They showed a reduction in plaques. The 2015 study showed no impact on CNS biomarkers. So apparently the specific lithium salt chosen might actually be critically important (or that effect might happen only in mice, or the presence of the biomarkers may not be correlated with the amount of plaque in the way that one might assume, or...).

I'm looking at the abstract of an article in the Journal of Alzheimer's Disease from 2015 that did a meta-analysis of placebo-controlled human trials of lithium in Alzheimer's patients that showed a statistically significant reduction in cognitive decline (albeit only barely significant at the 95% CI) from lithium supplementation, with approximately zero AEs.

It's not surprising that a mouse model study would support what human studies have already demonstrated, though I guess this is interesting in that it is presumably a larger study and more controlled than any meta-analysis would be.

One neat thing about this story is that the lithium salt that they chose (chosen because of its comparatively weak amyloid binding) is lithium orotate, which is commonly available over the counter as a dietary supplement from a rather large number of companies. If you have Alzheimer's and want to try it, there's literally nothing stopping you.