Having 5 smallish children, I get colds fairly frequently. 1 And every time I do, I invent this device.
Basically, it would be an ultraviolet light embedded in something that that kids touch at school every day. Doorknobs, maybe. It would sterilize their hands to prevent (so much) passing germs around. A less cancer-causing version of the idea would be to sterilize the doorknob after every use.
And now my dream is a reality.
- Actually, I don’t anymore. I think I’ve had all the colds there are now. ↩
In the previous post I was talking in system-wide terms. That plan envisions a significant fraction of homes generating their own power. But only an insignificant fraction of homeowners can afford to install multi-kW photovoltaic systems or build dams to drive expensive microturbines.
I don’t have a river, an ocean or a volcano in my back yard, so my house is pretty much limited to solar power. There was a relevant quote in the most recent issue of Make Magazine.
You can divide most solar power research into two camps: increasing efficiency or reducing cost.
I would like to add to that quote: “And one of these camps is barking up the wrong tree.”
Efficiency is a red herring when fuel is free and space plentiful. The sky is raining fuel, don’t break your back trying to squeeze every last watt out, just set out more buckets.
A typical home uses about 2-3kW averaged over a day. A square 6+ meters (20 feet) on a side, if converted at 10% efficiency, can power your home. That’s much smaller than your roof, let alone a typical yard. Not enough or want some backup? Just build another square. With a good, cheap design this should be easy.
So what’s needed is a good, cheap design for turning solar power into electricity. 1 The usual solution, since the chemical processes of PV are beyond DIY, is some kind of heat engine, usually a Stirling because of the simplicity.
Making a Stirling engine that runs on solar power is not that hard. Making a big one that could conceivably power a home is not much harder, provided you have access to pretty sizable machine tools. Stirlings are very uncomplicated, but any machine with moving parts and a requirement to be air-tight is going to need some special skills or tools. 2
And I think I’m going to leave this on that note. I have what I think is a good, simple, cheap design but I have to build and tweak it to make it work and have pictures/video.
I didn’t come up with this idea, I’m just explaining it as context for a future post. (Actually, I did come up with this idea, but then discovered it already existed.)
Executive summary: Every house would generate power from one of a number of sustainable sources. Any excess power is sold to the grid via net-metering while any deficit is purchased from the grid. (Existing power plants can remain to make up “global” deficits.)
There are a number of advantages of this.
- Every house is in a different location and can optimally exploit the local energy environment. For instance, if you are in the south and have no trees, you can use solar. If you have a stream on your land you can use hydro. Rancher in Montana? Install wind turbines.
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The local exploitation means that there are a diversity of energy sources. Right now, when oil prices go up we all suffer. Under a distributed, diversified energy system even large cost fluctuations in one energy source are amortized over the rest of the unaffected remainder.
Even better, diversity is actively incentivized. For instance, if all your neighbors are running solar and you choose hydro, you’ll have an advantage on cloudy days.
- One of the arguments always raised against solar energy is that you’d need such a large area to capture enough energy. This argument is pretty lame for multiple reasons, but it is true that a typical home would need several-to-many square meters. If all those square meters have to be next to each other, you need to use some enormous desert somewhere or something. But if those square meters are broken up and taken out of the square meters already allocated to each house the impact is much less.
- A distributed system is more reliable than a centralized one. Reliability is not usually a problem in the US power grid, but in some areas and at some times (think of after a hurricane) it can be. Right now, we have to wait for the power company to link up the entire path from generator to each home. Under the proposed plan, “island grids” could run from surviving power sources until full connectivity is restored.
Getting off Blogger wasn’t too hard, technically 1. All I really had to do was create a blog elsewhere and WordPress could even host it for me. But I decided to get my own domain. Because then I could…
Get off Gmail by creating an email account on the same domain.
But here was the really big problem: Google Reader. I need an RSS reader and it needs to be accessible from multiple locations. But I didn’t want it hosted by Google, because that means you have to be logged in to Google and THAT means all your Google googles are done while logged in. (Google claims to be not evil now, but absolute power corrupts absolutely.)
More generally, I didn’t want it hosted by anyone. I had a really tough time exporting my feeds from Bloglines back in the day. Other services are more open (for now) but again, power corrupts. And of course the ads.
But how do you have an RSS reader on the internet without it being hosted by some RSS service? One thing I tried was feed2imap. It’s a pretty good idea and probably works well when you only have a couple feeds to follow and can hand-tweak the settings for each. But it’s primitive and IMAP (or at least my IMAP) is slow, so it was frustrating.
Eventually I discovered that there are multiple, simple, self-hosting feed readers out there. Gregarius, rsslounge and lilina for instance. If your hosting provider 2 provides PHP and DB access, it only takes a few minutes to set these up. Really nice.
I’m still perfectly willing to use Google, I just don’t have to be logged in to do it now.
- Psychologically, the difficult can vary. Migrating stuff and people is a big deal if you have a lot invested in Blogger. But I didn’t really. ↩
- I realize that if I use a provider, all my mail, blog and RSS are still hosted by someone else. But first of all, it’s more portable because for instance my email address isn’t tied to the provider’s name. And secondly, the relationship is explicitly one of “hosting” so a potential claim by them that my data is theirs (to own or data-mine) has less weight. ↩
I’ve been working (off and on) on an energy project that I’ll talk more about in the future. For the time being, here’s how much energy my house uses:
| Date | KWH | Days | KWH/day | Charge | Avg °F |
| 10/19/2009 | 896 | 31 | 28.90 | $145.71 | 52.9 |
| 9/18/2009 | 976 | 30 | 32.53 | $157.85 | 66.5 |
| 8/19/2009 | 826 | 19 | 43.46 | $130.86 | 74.2 |
| 7/31/2009 | 608 | 14 | 43.45 | $96.90 | 72.5 |
| 7/17/2009 | 954 | 31 | 30.77 | $154.95 | 67.2 |
| 6/16/2009 | 763 | 29 | 26.31 | $125.72 | 62.3 |
| 5/18/2009 | 851 | 32 | 26.59 | $139.19 | 57.8 |
| 4/16/2009 | 822 | 29 | 28.34 | $134.74 | 42.6 |
| 3/18/2009 | 826 | 28 | 29.50 | $135.36 | 32.8 |
| 2/18/2009 | 987 | 33 | 29.91 | $160.00 | 24.5 |
| 1/16/2009 | 505 | 16 | 31.54 | $81.87 | 19.7 |
| 12/31/2008 | 473 | 15 | 31.54 | $73.42 | 27.2 |
| 12/16/2008 | 883 | 28 | 31.54 | $137.91 | 32.5 |
| 11/18/2008 | 799 | 29 | 27.55 | $125.61 | 47 |
| 10/20/2008 | 1002 | 32 | 31.31 | $155.26 | 55.6 |
| 9/18/2008 | 939 | 30 | 31.30 | $145.78 | 68.1 |
| 8/19/2008 | 1483 | 33 | 44.94 | $225.06 | 71.6 |
| 7/17/2008 | 1326 | 31 | 42.77 | $202.18 | 72 |
| 6/16/2008 | 909 | 28 | 32.46 | $133.42 | 66.2 |
| 5/19/2008 | 856 | 31 | 27.61 | $126.17 | 54.8 |
I read somewhere that homes use about 3 KW continuously, so I’m glad that my average seems to be closer to 1.5-2 KW. Of course, that doesn’t include heat.
Running XBMC on the pretty sweet-especially-for-the-price Acer Aspire Revo 1600. Most audio is working, but not AC3. Tried a few things, including this impressively comprehensive pulling-together of a lot of different things. Nope. (btw, devolblog, that should be ctrl-alt-f2 to bring up the terminal window.)
Turns out the solution was to read what the option page was telling me. Like the “passthrough” option is asking how I want to “pass” audio “through” to the receiver. And it also asks if the receiver is AC3-capable. And if I want to downmix to stereo. Once I answered correctly (HDMI, no and yes respectively) it worked fine.
Now I need to figure out how to get it to play an entire directory at a time, rather than single files. AND keep a bookmark of how far it got. Also, why my network speed is so low, although to be fair I think that’s either the USB or the router or both. Or possibly Bit Gnomes are stealing my packets.
This whole thing is reminding me of the good ol’ days of Linux. Remember recompiling your kernel to install new fonts? Or modprobe ways_to_school.so before you could walk uphill both of them?
This wasn’t my biggest present, but it probably was the one that the other Christmas participants would most like to see the final result of. So…here it is.
I’m not a “papercraft” person, but this was really fun, easy and cute.
So this is a weird post. I’m mainly putting this here because I wondered it some months ago, figured out an “answer” and then wondered it again recently but couldn’t remember the answer. This time I’m writing it down.
Assumptions:
- A reasonable amount of the more-or-less everyday speech I’m using can be translated into meaningful “real” mathematical language. I don’t really know that much about information theory, Gödel or cosmology. There is a more-than-slight possibility that the ravings that occur below are more a function of my confusion and ignorance than anything that’s actually true.
- The universe has some maximum information content. This might be because of a maximum extent (in both space and time) coupled with a maximum informational density (planck scale limitations) or for some other reason.
- Mathematics is “contained by” the universe. That is, the information that is present in mathematics must be counted against the above information budget that the universe has.
Assumptions 1 and 2 immediately create a problem because the informational content of mathematics would seem to be infinite.
First of all, this is not because the set of integers is infinite. A big pile of stuff only has as much information as the simplest representation of it. So for instance it’s very easy to generate numbers by saying something like “print 0, then print 1 + the last number you printed, repeat”. That algorithm doesn’t have a lot of information in it.
The apparently infinite informational content of mathematics is also not due to us proving new theorems all the time. Theorems are logical necessities of the axioms. If I know both “A” and “A implies B” then finding out “B” is not news. It was inherent in the things I already knew.
But what about Gödel’s Theorem? He proved that there are always statements that are unprovable in the new system. You can add them in, but then there are more. These must be new information because they are by definition not inherent in the things I already knew. But if you can always find these statements, isn’t that an infinite amount of information? Where are these statements coming from, if not from inside the informationally finite universe?
Or here’s another way to state the same problem. We can consider the entire universe from the Big Bang to dinosaurs to mammals to humans to be one huge, very complicated algorithm for generating mathematics. “In order to create mathematics from scratch, you must first invent the universe” to paraphrase Carl Sagan. Let’s call this the Big Algorithm.
This algorithm (by assumption #1) has some finite informational content. Therefore the stuff it produces has no more information than that. But Gödel(‘s Theorem) claims he can generate infinite information.
I think this is the thing: The statements that Gödel produces aren’t information themselves. It’s the decision whether to accept or reject the statement as a new axiom that’s information. For instance, I might make the statement “C = ℵ1“. As it is, that’s just a bunch of symbols set in a certain order. If I decide to say “yes, this is true” or “no, this is not true” then it’s information.
So now let’s go back to the Big Algorithm. Instead of this finite algorithm generating infinite information, it’s just emitting statements to which humans (who are part of the Big Algorithm) are assigning truth values. We have an infinitely long string of 0s and 1s representing the truth values of all these statements. That infinitely long string must have a finite informational content because it was generated by the BA. Basically, we are forced to assign truth values non-randomly over the long haul.
—-
That’s as far as I got with this last time I thought about it. But in writing this, I’ve found another problem. Gödel says that the new statements are unprovable using the existing statements. That is, the truth value of a new statement is independent of the truth value of all the other statements.
But the BA has to be assigning the truth values algorithmically, which is to say non-randomly, which means the truth values are not independent.
Maybe the real answer is that the real universe is non-gödelian in the exact same way it is non-euclidian. One of the axioms of geometry is only true of a mathematically ideal plane but not true of the real universe. Perhaps one of the axioms of….whatever Gödel was assuming….is also not true of the real universe.
Another potential answer is that I have no idea what I’m talking about.
Number Two Son (age 8) loves crafts, loves little fuzzy things and loves kawaii cartoon faces. So amigurumi is a no-brainer. Except that none of us knew to to crochet.
But it’s easy to learn, even with terribly written and illustrated instructions from a lame book (NOT THAT I’M SAYING ANYTHING). Here’s my First Official Thing:
