Archive for November 2010
No one showed up. Oh well.
I don’t think people realize the potential here. The software, in my experience is quite amazing. It’s videoconferencing. You can talk to other people quite easily. You should at least try it out with your friends and family.
Think about what exactly this is here, a meeting can be held that is not just a meetup of people in your area, but ANYONE IN THE WORLD with an internet connection.
If you have nothing interesting to talk about, sorry, but the problem lies squarely with you. And yes it’s a problem, a failure to converge. Humans need to converge, to organize, in order to accomplish things, true fact.
It reminds me of a TEDTalk by Melinda Gates I saw a while ago, about implementing various medical interventions in developing countries – people need them and it’s a good thing, and the people know that perfectly well. But that is not enough. You still have to make them want it if they are going to take it, even for free.
I could maybe register a domain name, get some flashy stuff going on there, maybe spend too much money on some inferior software so it looks more “professional”. Maybe make a bunch of cons specific to various localities. Maybe that wouldn’t be enough, and I would have to keep trying more and more things.
Well, frankly I don’t have the time or money to do that, I’m afraid. I’ll continue hosting the con for a while longer, but maybe after 7 or 8 I’ll give up. I’ve done my part. If people don’t want it, that is your responsibility, I just can’t afford right now to do that much that it takes to make people want it.
If you haven’t done so yet, download and run Vsee. There’s no install to go through. When you run the program, it will prompt you to fill out a short form to sign up but you can enter anything you want, and there is no confirmation email or waiting.
Then simply use the ID below to call me:
I will then add you to the meeting. If a number of people show up I will add other IDs you can call to the list.
Think of the IDs as names of different rooms.
There is also one tinychat room in case Vsee is not working out for some reason:
VirtualTinyHouseCon Tinychat room
This is something I have wanted to check for a while now. The info used for the graph is all very rough, but it gives the general idea anyway. A used car is cheaper by weight than the structure of a house (which excludes the foundation). In fact, you can get a brand new car for less by weight than a new house structure!
The price of the typical used car is just eyeballed from looking at the kijiji ads, but for sources of the rest of the info used, see links below.
Why does this matter? Well think about it for a second: Modern Car = extremely sophisticated, accurately made piece of machinery made from expensive materials. House = bunch of wood and junk kind of slapped together. Buildings should be very cheap on a weight to weight basis, right? If these things were anywhere near each other in cost on a weight to weight basis, that would be remarkable enough.
Indeed, the Tata Nano is an extraordinary car, but the principle here is still very sound. It’s still a freaking car, and extraordinary piece of manufactured stuff, sold at the usual profit margins etc. Also, as you can see, a cheap used normal car is still going to usually be cheaper than a used house structure.
Ladies and gentlebeans, this situation makes no sense. Clearly the housing and construction market is totally messed up, maybe because innovation has been deliberately prevented for probably more than a hundred years.
But wait – why not apply the lessons learned and technology used with cars to build housing? Oh wait wait, no no. That’s too much like innovation, can’t have that.
That’s exactly what prefab was and partly still is and today, even despite the government’s attempts to destroy the idea, it is cheaper and better. I have read several times that you can get a house that is exactly as good for 30% less. You’d think that would be something that the government would be trying to encourage or something. If you were silly enough to think the government is actually working for we, the people.
I’ll grant that you can probably save a lot of money by using plywood floors or something, but that doesn’t change things that much.
http://www.ontariocontractors.com/buildcalc.htm minus 18,000 for the cost of the foundation
To eliminate echo for other users (which occurs when your microphone can hear your speakers), there are a number of options, one of which should be easy for almost anyone:
– Simply use a computer with Windows vista ro windows 7. The OSes have built in echo cancellation technology. Handy.
-Use earbuds (like for an Ipod, it does not need to have a microphone built in) or heaphones with your computer’s or webcam’s built in microphone.
– use a headset, those things with a microphone and headphones put together.
– simply turn your microphone off, just by clicking the microphone icon in Vsee. You will be able to hear everyone, but not speak by audio. You can still type in the text chat window.
Remember, download Vsee here. Just run it, there’s no install, and then just enter whatever you feel like in the very short signup screen. There is no waiting or confirmation email.
Well, it was more interesting than last time! 2Coyotes came, but no one else. We talked for about 50 minutes about a bunch of stuff.
Including the con, trying to figure out a way to cajole all you antisocial old goats into coming.
Bill preferred tinychat because there is some sort of bothersome setup required to use vsee on an mac. We tried the audio/video feature. It was fine for me, but it looks like I should get a headset to reduce the echo that bill was getting, or use the push to talk option (which oddly didn’t occur to me at the time) which would prevent the echo so long as I was not pushing the talk button, which should be the norm when someone else is talking. That would eliminate the sound of my typing too, which was an issue. Or tweaking the audio settings could help some, come to think of it, you want low microphone sensitivity and speaker volume on the echo producing side (mine), then increase the speaker volume on the side that has a headset to compensate. Or I could use a normal keyboard so I can type faster and not transmit audio at all. Using Vsee might help too.
I’ve said it before and I’ll say it again: You need a good communication platform, and then add people with something interesting to talk about (which I think tinyhouses definitely qualify as).
I have a blog post up in which I post the notes I took (and I’ve since done a fair bit more investigating, I should add those notes to the post later) on the different software options, finding and looking at maybe 20 options. If what I found is not enough, and maybe the hardware people tend to possess (e.g. lack of headphones and sound cards like mine that cannot filter out their own echo, though there are some that can) is not good enough, then the state of technology is not good enough at this point in history to hold a con like this.
Personally I think it is more than adequate though, to share ideas, experience, meet people, all that, really. Is that not the main attraction of a conference?
It continues to perplex me that of the probably much >20,000 people that read tinyhouse blogs, almost none are apparently interested in meeting others interested in the topic.
Anyway, remember, VirtualTinyHouseCon will be held again every Saturday, at 8 PM, so the next one is on Nov 27. It will probable be held like this time, primarily with Vsee, and with a backup tinychat room.
If you haven’t done so yet, download and runVsee. There’s no install to go through. When you run the program, it will prompt you to fill out a short form to sign up but you can enter anything you want, and there is no confirmation email or waiting.
Then simply enter one of the IDs below to call me:
I will then add you to the meeting.
Think of the IDs as names of different rooms.
There is also one tinychat room in case Vsee is not working out for some reaso:
VirtualTinyHouseCon Tinychat room
Okay. So some good news today! I looked into the possibility of building a reverso osmosis unit that can filter greywater to some degree. Reverse osmosis is good stuff. Looks like it is totes doable for $350-$700, depending how much you shop around for a good deal on the parts (and it seems to vary greatly) for the 70 liters a day needed. Increase that, but less than linearly, for more water, when you upsize the pump and the cost does not go up that fast, a 2x size membrane and pressure vessel is again not twice the cost.
Actually, you might be able to do this for even less with under the tap RO stuff. Tap water is apparently 500 ppm so that shouldn’t be a surprise, but it’s probably not going to get you a very high recovery rate (unless you use several RO modules) and would be less energy efficient. Just use a bunch of the membranes, and actually using a CA membrane might be a little better because they can withstand chlorine, so that could help reduce growth of microbes. That I think would be a substantial concern, bacteria could grow on the surface of the RO membrane, thusly clogging it. Apparently an “osmotic backflush” can help to some degree with this sort of thing, though. You just turn the pump off for 15 minutes, and water goes from the clean side, backwards to the dirty side, lifting a bunch of dirt off in the process. Scaling might or might not be a problem, that would require further investigating.
Anyway, it goes like this:
Seawater salinity: 35,000 ppm, osmotic pressure: 27 atm (394 psi) (from the wikipedia article on osmosis)
Greywater: about 1000 PPM (from my notes) osmotic pressure: 0.77 atm (11 psi) (might be higher in a situation with water saving shower heads etc. but then lower again if you don’t put food or whatever down the drain).
If recovery rate is 50% then the salinity at exit is 2x so the average pressure diff across membrane is that much lower.
Example membrane: http://www.discountedwaterfilters.com/Filmtec-SW30-2514-Sea-Water-Reverse-Osmosis-Membrane-SW30-2514.htm
GPD: 150 gpd or Gallons Per Day
PSI: 800 PSI
Stabilized Rejection: 99.4 Rejection
Example Pressure vessel, surely you can get a much better price we only need 120 psi capable, which even an under the counter unit residential unit can handle, but it gives you an idea of what I’m talking about, I started looking into this under the assumption that I would need high pressure stuff, that is why I used this :
Okay, so that membrane only gets 150 gpd at a recovery rate (dirty water going in/clean water out) of 2%, which is just the test condition, not the expected operating condition. If you operate it at 50% level, basically think of this as a whole lot of RO elements in series, the dirty water goes through one, get a bit concentrated, then through the next one and is a bit more concentrated, and then the next one… anyway, by the time it gets out, it’s salinity (and therefore osmotic pressure, assuming the salt involved is the same salt, which if course it is) is twice as high.
Remember the rate of water flow across the membrane is proportional to the input pressure minus the osmotic pressure difference on the clean and dirty sides (I assume it’s 0 on the clean side). So obviously if the input pressure was 800 psi, and seawater is 394 psi you would never really be able to practically get a 50% recovery rate.
With 800 psi input with greywater though it is not a problem, going from 11 psi to 22 psi isn’t going to affect the flow rate much. But 800 psi pumps are relatively expensive (uh, I think, well pressure washers are pretty cheap, so maybe you could find a high pressure pump, would probably have to be a piston pump, that would open up interesting options for high recovery rates)
Also, the pressure drop across the membrane is much higher to begin with, so you would get that much more flow through it.
So to find out what sort of flow rate you would get with input osmotic pressure of A and output osmotic pressure of B and pump pressure of pp, and a flow constant of L (the flow rate decays exponentially with time as concentration goes up), so the initial flow rate is (pp-A)L, when is done flow rate is (pp-B)L so you would find what t is for those points and find integral between them and then divide by time difference to find average flow. But what is L, well at 394 psi input and 402 output and 800 input pump pressure (so (pp-a)=407 and (pp-b)=398) got flow of 150 gpd so just suppose L 150/400 gpd about or 0.375 gpd/psi.
So for us, at a pp of 120 and A of 11 and B of 22 (pp-A)=109 (pp-b)=98 or ~37.5 gpd. So if you only wanted 17.5 gpd you could get more than 50% recovery with this setup, actually maybe 80% or more.
An example pump (one issue is that most pumps are made for much much higher flow rates): http://www.freshwatersystems.com/p-1223-8800-series-booster-pump-24-vac-38-push-in.aspx?affiliateid=10050&qid=0&utm_source=Googlebase&utm_medium=Feed&utm_campaign=Product&utm_term=8852-2J03-B423
You still need to filter the water to get the particles out though, or they stick to the RO membrane (mind you I wonder if you could get around that with osmotic backwashing so you didn’t even need to particle filter it, but the particles might also physically clog the membrane element, as I don’t think they are made to pass particles very well, maybe you could find one that is, maybe a flat plate module).
This could be a great way to boost a rainwater collection system, greatly reducing the amount of rain water needed, or could be used in combination with an MBR (which provides low maintenance particle filtering and disposes of the wastewater that comes out of the RO unit). There are some things that can pass through an RO membrane, urea is one, but it gets probably almost all of the stuff, and urea isn’t harmful especially at these levels, and very improbable that anything else in the water is, I think. Obviously you can’t flush toxic stuff down on purpose but if you’re just showering, washing dishes, doing laundry, whatever went down the drain is probably something that you put on your skin in much larger quantities at some point, and probably already ingest some of (including laundry detergent, there is always some left on the clothes). Mobile Condo people, do you read me?
There is one thing that nags at me, which is that you have to really wonder why this is not done with those water recycling systems for sale in Australia. I have however read of it being done in cruise ships, and also that Marco Cremona guy in Malta used RO. Maybe it is maintenance issues or something, it seems like the main unknown here is the potential for membrane cloggage, but I think it is definitely worth trying. The Malta guy was a pro in RO system design, incidentally.