Home energy storage is an interesting idea, even with just the grid (and no local solar or wind). It has the potential to allow a home customer to average out their power usage over some period of time, which makes managing the grid easier. Right now the way homeowners are charged for power I don't see this making much sense, but the pricing scheme could be structured to reward people for doing this which would mean less spent on peaking power.
This is true, but even without renewables energy storage is a good tool to have available to the grid. Batteries and inverters are capable of sourcing and sinking power, as well as ramping up and down fast, making them good candidates for frequency regulation and other ancillary services. For example, by spacing storage systems around, you can also help avoid congestion on large transmission lines.
Along the discussion of the DC home, a good inverter and maybe dedicated DC outlets. Maybe just feed outlets directly from solar/wind battery bank.
I'd add switchable glass windows to go "opaque" whenever I wanted, at least in the bedrooms.
Running low voltage DC over long distances properly is difficult, as you need bigger wiring, switches, fuses, etc. I'm not sure I'd want to do a lot of home wiring with it. Modern inverters are relatively efficient and fairly reliable. I would say that the way to go would be to pick out a few circuits for 'critical' loads you would like to be able to supply backup power to or run off grid, and run them into a separate sub panel. You could either just wire this into your main panel during construction, or install a battery/inverter system right away that would act like a big UPS to the loads on the sub panel. You can get inverters that will work with batteries, but push excess power from solar/wind into the grid while the grid is up. If it goes down, you can run your critical loads on battery power.
For some low voltage things I'd maybe consider a separate, smaller PV system and locate it close to the load, maybe for something like garden lights or ham radio gear.
Higher voltage DC is an interesting idea, especially since you could probably run a lot of switching supplies off of it - some data centers do this. However you need special switches and fuses to be able to interrupt it. I'm not sure 120/240 VDC is something I'd want in my home.
So let's suppose we charge everyone a connect fee for grid maintenance. That covers the cost of maintaining transmission systems, LV networks and excess unused capacity. It will also raise the cost of utilities for the poorest fraction of society. I was shocked to learn that there is a large segment of utility customers who use very little electricity. A connect fee would, for many of them, be a significant price increase.
Solar aside, people aren't really just paying for their usage. As you pointed out, part of the bill goes toward maintaining infrastructure. To the end user, this doesn't just mean that their usage is covered, it means that their usage pattern is covered as well. Some customers may not use much energy, but they may want to start a large load once in a while.
For instance, I don't use a lot of power, but suppose I came home and found three feet of water in my basement, so I go out and rent a couple of big submersible pumps. I run these for a couple hours, and my instantaneous power usage is around 4 kW during that time. Even if this is still a relatively small part of my bill (it would be about $1), it's still a lot more power than I normally use, and the grid has to be able to support that, and ideally it would be able to support that whenever I needed it.
Now, I think that the connection fee could be adjusted depending on the particular installation (eg, residential vs industrial, city vs country, etc), but I don't think it's necessarily unreasonable in and of itself.
I ran the numbers a while back regarding the electric usage in my apartment along with the connection fee. (That means that the less energy I use, the more my cost per kWh effectively goes up since more of my bill is the connection fee.) I found that, for my usage (90 kWh/month), I could almost put together an off-grid system that would effectively cost me the same or less. That assumed I'd do the installation myself, of course, and it's not really something I plan to do. But it was interesting.
There definitely are times when the off-grid route would be cheaper. If you had some remote land you wanted to put a small cabin on (or maybe just some kind of radio repeater or something), depending on your usage it could very well be the better deal to go off-grid. On the other hand, for a normal suburban home I agree with you, batteries need to come down. Used electric car batteries could make things interesting, though.
That's why it's a good idea to encrypt data over Tor whenever possible - it's really only there to anonymize. If you're careful and stick to SSL-capable sites for things like email and banking, you should be fine. Otherwise, yes, assume someone will sniff your password.
This is not simply hooking you into the grid. This is also putting in equipment to allow you to push power BACK to the grid. That's neither inexpensive, nor trivial.
What equipment on the grid are you referring to here, aside from maybe meters that are asble to sense power moving in either direction?
Many people do not realize that solar installs will go dark during a blackout with out these very large and uber expensive battery systems.
In most cases this is true, the invereters designed to work in pure grid-tied systems won't supply power without a battery. SMA however has an inverter that can supply some power (up to 1500 watts) during a grid outage, while the sun is up. Obviously it doesn't work at night, but in the event of some kind of disaster at the very least you can charge cell phones, laptops, or whatever when there's sun. Hopefully this is something that starts showing up in other inverters.
On the other hand, if you have something that would require a UPS anyways, a hybrid inverter and battery might just be the way to go.
Anyone have experience with non-root tether apps on Android?
If you don't mind getting your hands a little dirty with adb and OpenVPN, you can take a look at azilink. It basically runs a Java-based NAT on your phone, which communicates with OpenVPN on your computer. I had some issues with the app on the phone crashing once in a while, but for the most part it works. It might work better for you.
Out of curiosity, what are your feelings with encryption regarding HSMM-MESH? I mean in terms of controlling other nodes - if I have a router set up in a remote location, I want to be sure that no one else can take control of it unless I allow them. This is especially an issue as the hardware is fairly ubiquitous and well-known outside the ham community, so I would be concerned with security regarding outsiders.
The proposal mentions encryption in the case of controlling an unattended station. I don't think this is a bad idea (so, in the case of HSMM-MESH you could use SSH or HTTPS to manage a node), although I do understand the general objection toward encrypting general traffic. I suppose too that as long as the node could verify your identity you wouldn't need to necessarily encrypt, as long as it was done so that no one could tamper with the signal.
The other thing is that it's not like one person would have to tie a charging slot up for two hours while their phone charged. If people with dead phones plugged in for a few minutes a lot of them could get just enough of a boost in for a quick phone call or some text messaging. It's not a lot, but for a lot of people it could be great for getting a word out to friends and family. It doesn't have to fully charge everyone's phone to be effective.
This really depends on how they're built, and where they're sited. If they pay attention to those details there's a good chance that something that would take out the power would leave the kiosks usable. Strengthening the infrastructure is good and should also be done, but then it's still a major point of failure. At leas this is some additional redundancy.
There's actually an amateur radio project to create a mesh network, as WiFi channels 1-6 actually fall into the ham bands. It's not very widespread in that you can just set up a node and get on, but it is pretty easy to deploy at events or in emergencies - just take the router out and plug it in. The site is hsmm-mesh.org.
A lot of the visual effects companies tend to run Linux on workstations (except for things like Photoshop, obviously), as well as on the servers. Not sure what Pixar's using on their workstations, but either way 3D modeling and compositing are different beasts than editing.
That said, there are a few commercial video editors that seem to support Linux; I found out about Mistika on Wikipedia. I'm not sure how widely systems like that are used, though.
Another option is to take a normal car and add a couple deep cycle batteries and charge them from a battery isolator. These are used in RVs, and let you charge the other batteries from the alternator along with the starting battery while not letting both banks drain all the way down (so you can still start your car). Then get a big inverter and hook it to the deep cycle batteries. Of course, if you need a lot of power a dedicated generator may be easier.
If/When this comes to market, it will hopefully have some protection built in. In part, if their circuit sensed existing voltage on the output, it should shut off. Sort of similar to photovoltaic intertie inverters, though they're meant to run in phase with the grid and then detect when its down. Basically, the problem you refer to is called islanding, and there are some methods to avoid it. And of course, you can't always outsmart a fool, but some protection is better than nothing.
A decent quality inverter should be able to handle the startup, but sizing it to be a bit bigger than you need is a good idea, as is making sure you don't skimp on inverter-to-battery cabling. Even better, if you are going to set up a bit of a larger backup system, is if you can use a 24 or 48 volt battery and inverter instead of 12. (Then maybe you'd charge it from a generator, or some solar panels if you want.) Less DC amps makes it easier to start bigger things.
This is a risk you run even with people who don't know what they're doing connecting a generator during a power failure. Hopefully anyone playing with an alternative energy source in their own home (solar/wind, or generator) will do a some of their homework and avoid this. In the case of grid tied solar, pretty much all domestically available grid-tied inverters have very rigorous protection to avoid an islanding situation. Even if they're not installed exactly up to code they should be able to detect this and not backfeed the grid.
Then again, someone can still be a moron and connect a non-grid-tie inverter up during a power failure and backfeed, so who knows. I guess this is bound to happen at some point, but hopefully most DIY people learn enough to know why this is bad by the time they get to this point.
I got curious about it and tired it out in a VM once. It was neat, from the standpoint of playing around with a different UNIX variant that I could get for free, but beyond that, what would be the point? It may be the core of OS X, and I'm sure it's a big help for people who want to do things like write device drivers for OS X, but I'm not sure I've heard of anyone using it as a desktop or a server (I mean aside from an OS X machine). So while you may be able to grab it and use it, if you want a server or a free UNIX-like desktop you may as well just go with a Linux distro or a BSD.
I mean, I'd be interested to hear if anyone uses OpenDarwin (or one of the variants) regularly, but it seems like for most things there's not much point.
Yeah, I have an Octane II. I don't browse the Web on it, but from time to time I use it for some graphics work. Namely, Photoshop 3 came with it. It still runs beautifully. When I'm not doing that I use it as a foot stool or as reinforcement for the pile of papers and other stuff in my work area. It's a very sturdy machine.
Coal is wood from the past, you know, wood which is made out of Carbon that didn't get released into the atmosphere.
Yes, coal is indeed wood (and other organic matter) from the past, as is oil. The very distant past. It was once part of the carbon cycle, but after getting buried and compressed (and thus formed into coal/oil) the carbon cycle in the atmosphere gradually worked around it (over millions of years). So digging it up and burning it puts that back into the current atmosphere and carbon cycle, which could cause problems. IE, I don't expect the trees to get re-sequestered like the ones that became fossil fuels back in the day.
On the other hand, I guess it would be possible that by planting all the trees you would help the carbon cycle adapt to the increased carbon. Again I'm not sure, but I suppose planting more trees would be a good thing even if it doesn't completely solve the problem.
I've never a post explaining why they are not real.
I'm not totally sure, but I would imagine it would be something like this: When you burn a fossil fuel, you're taking carbon that was sequestered in the ground and reintroducing it into the natural carbon cycle, thus throwing things off (eg, climate change). Now, if the carbon credits work by having some company agree to plant enough trees to absorb a certain amount of carbon (say the equivalent to the round trip flight to Tahiti), the trees will in absorb it, but the carbon hasn't actually been taken out of the cycle. IE, they will die or get eaten by something, and the carbon will still get released into the atmosphere eventually.
On the other hand, if the credits work by using some renewable source to displace carbon that would otherwise be released from fossil fuels (for instance if a company agreed to generate a certain amount of electricity from solar and pump it into the grid; again I'm not completely familiar and am taking a stab), then in theory there would be some benefit. But then you could just cut out the middleman and not take your flight or your long drive or whatever.
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Home energy storage is an interesting idea, even with just the grid (and no local solar or wind). It has the potential to allow a home customer to average out their power usage over some period of time, which makes managing the grid easier. Right now the way homeowners are charged for power I don't see this making much sense, but the pricing scheme could be structured to reward people for doing this which would mean less spent on peaking power.
This is true, but even without renewables energy storage is a good tool to have available to the grid. Batteries and inverters are capable of sourcing and sinking power, as well as ramping up and down fast, making them good candidates for frequency regulation and other ancillary services. For example, by spacing storage systems around, you can also help avoid congestion on large transmission lines.
Along the discussion of the DC home, a good inverter and maybe dedicated DC outlets. Maybe just feed outlets directly from solar/wind battery bank.
I'd add switchable glass windows to go "opaque" whenever I wanted, at least in the bedrooms.
Running low voltage DC over long distances properly is difficult, as you need bigger wiring, switches, fuses, etc. I'm not sure I'd want to do a lot of home wiring with it. Modern inverters are relatively efficient and fairly reliable. I would say that the way to go would be to pick out a few circuits for 'critical' loads you would like to be able to supply backup power to or run off grid, and run them into a separate sub panel. You could either just wire this into your main panel during construction, or install a battery/inverter system right away that would act like a big UPS to the loads on the sub panel. You can get inverters that will work with batteries, but push excess power from solar/wind into the grid while the grid is up. If it goes down, you can run your critical loads on battery power.
For some low voltage things I'd maybe consider a separate, smaller PV system and locate it close to the load, maybe for something like garden lights or ham radio gear.
Higher voltage DC is an interesting idea, especially since you could probably run a lot of switching supplies off of it - some data centers do this. However you need special switches and fuses to be able to interrupt it. I'm not sure 120/240 VDC is something I'd want in my home.
So let's suppose we charge everyone a connect fee for grid maintenance. That covers the cost of maintaining transmission systems, LV networks and excess unused capacity. It will also raise the cost of utilities for the poorest fraction of society. I was shocked to learn that there is a large segment of utility customers who use very little electricity. A connect fee would, for many of them, be a significant price increase.
Solar aside, people aren't really just paying for their usage. As you pointed out, part of the bill goes toward maintaining infrastructure. To the end user, this doesn't just mean that their usage is covered, it means that their usage pattern is covered as well. Some customers may not use much energy, but they may want to start a large load once in a while.
For instance, I don't use a lot of power, but suppose I came home and found three feet of water in my basement, so I go out and rent a couple of big submersible pumps. I run these for a couple hours, and my instantaneous power usage is around 4 kW during that time. Even if this is still a relatively small part of my bill (it would be about $1), it's still a lot more power than I normally use, and the grid has to be able to support that, and ideally it would be able to support that whenever I needed it.
Now, I think that the connection fee could be adjusted depending on the particular installation (eg, residential vs industrial, city vs country, etc), but I don't think it's necessarily unreasonable in and of itself.
I ran the numbers a while back regarding the electric usage in my apartment along with the connection fee. (That means that the less energy I use, the more my cost per kWh effectively goes up since more of my bill is the connection fee.) I found that, for my usage (90 kWh/month), I could almost put together an off-grid system that would effectively cost me the same or less. That assumed I'd do the installation myself, of course, and it's not really something I plan to do. But it was interesting.
There definitely are times when the off-grid route would be cheaper. If you had some remote land you wanted to put a small cabin on (or maybe just some kind of radio repeater or something), depending on your usage it could very well be the better deal to go off-grid. On the other hand, for a normal suburban home I agree with you, batteries need to come down. Used electric car batteries could make things interesting, though.
That's why it's a good idea to encrypt data over Tor whenever possible - it's really only there to anonymize. If you're careful and stick to SSL-capable sites for things like email and banking, you should be fine. Otherwise, yes, assume someone will sniff your password.
Could you elaborate? What other equipment are you talking about?
This is not simply hooking you into the grid. This is also putting in equipment to allow you to push power BACK to the grid. That's neither inexpensive, nor trivial.
What equipment on the grid are you referring to here, aside from maybe meters that are asble to sense power moving in either direction?
Many people do not realize that solar installs will go dark during a blackout with out these very large and uber expensive battery systems.
In most cases this is true, the invereters designed to work in pure grid-tied systems won't supply power without a battery. SMA however has an inverter that can supply some power (up to 1500 watts) during a grid outage, while the sun is up. Obviously it doesn't work at night, but in the event of some kind of disaster at the very least you can charge cell phones, laptops, or whatever when there's sun. Hopefully this is something that starts showing up in other inverters.
On the other hand, if you have something that would require a UPS anyways, a hybrid inverter and battery might just be the way to go.
Anyone have experience with non-root tether apps on Android?
If you don't mind getting your hands a little dirty with adb and OpenVPN, you can take a look at azilink. It basically runs a Java-based NAT on your phone, which communicates with OpenVPN on your computer. I had some issues with the app on the phone crashing once in a while, but for the most part it works. It might work better for you.
I would second this. I've got a 2d3 I run OpenBSD on for a firewall, and it works pretty well.
Just add enough enough worcestershire sauce and it'll be fine.
Out of curiosity, what are your feelings with encryption regarding HSMM-MESH? I mean in terms of controlling other nodes - if I have a router set up in a remote location, I want to be sure that no one else can take control of it unless I allow them. This is especially an issue as the hardware is fairly ubiquitous and well-known outside the ham community, so I would be concerned with security regarding outsiders.
The proposal mentions encryption in the case of controlling an unattended station. I don't think this is a bad idea (so, in the case of HSMM-MESH you could use SSH or HTTPS to manage a node), although I do understand the general objection toward encrypting general traffic. I suppose too that as long as the node could verify your identity you wouldn't need to necessarily encrypt, as long as it was done so that no one could tamper with the signal.
The other thing is that it's not like one person would have to tie a charging slot up for two hours while their phone charged. If people with dead phones plugged in for a few minutes a lot of them could get just enough of a boost in for a quick phone call or some text messaging. It's not a lot, but for a lot of people it could be great for getting a word out to friends and family. It doesn't have to fully charge everyone's phone to be effective.
This really depends on how they're built, and where they're sited. If they pay attention to those details there's a good chance that something that would take out the power would leave the kiosks usable. Strengthening the infrastructure is good and should also be done, but then it's still a major point of failure. At leas this is some additional redundancy.
There's actually an amateur radio project to create a mesh network, as WiFi channels 1-6 actually fall into the ham bands. It's not very widespread in that you can just set up a node and get on, but it is pretty easy to deploy at events or in emergencies - just take the router out and plug it in. The site is hsmm-mesh.org.
A lot of the visual effects companies tend to run Linux on workstations (except for things like Photoshop, obviously), as well as on the servers. Not sure what Pixar's using on their workstations, but either way 3D modeling and compositing are different beasts than editing.
That said, there are a few commercial video editors that seem to support Linux; I found out about Mistika on Wikipedia. I'm not sure how widely systems like that are used, though.
Another option is to take a normal car and add a couple deep cycle batteries and charge them from a battery isolator. These are used in RVs, and let you charge the other batteries from the alternator along with the starting battery while not letting both banks drain all the way down (so you can still start your car). Then get a big inverter and hook it to the deep cycle batteries. Of course, if you need a lot of power a dedicated generator may be easier.
If/When this comes to market, it will hopefully have some protection built in. In part, if their circuit sensed existing voltage on the output, it should shut off. Sort of similar to photovoltaic intertie inverters, though they're meant to run in phase with the grid and then detect when its down. Basically, the problem you refer to is called islanding, and there are some methods to avoid it. And of course, you can't always outsmart a fool, but some protection is better than nothing.
A decent quality inverter should be able to handle the startup, but sizing it to be a bit bigger than you need is a good idea, as is making sure you don't skimp on inverter-to-battery cabling. Even better, if you are going to set up a bit of a larger backup system, is if you can use a 24 or 48 volt battery and inverter instead of 12. (Then maybe you'd charge it from a generator, or some solar panels if you want.) Less DC amps makes it easier to start bigger things.
This is a risk you run even with people who don't know what they're doing connecting a generator during a power failure. Hopefully anyone playing with an alternative energy source in their own home (solar/wind, or generator) will do a some of their homework and avoid this. In the case of grid tied solar, pretty much all domestically available grid-tied inverters have very rigorous protection to avoid an islanding situation. Even if they're not installed exactly up to code they should be able to detect this and not backfeed the grid.
Then again, someone can still be a moron and connect a non-grid-tie inverter up during a power failure and backfeed, so who knows. I guess this is bound to happen at some point, but hopefully most DIY people learn enough to know why this is bad by the time they get to this point.
I got curious about it and tired it out in a VM once. It was neat, from the standpoint of playing around with a different UNIX variant that I could get for free, but beyond that, what would be the point? It may be the core of OS X, and I'm sure it's a big help for people who want to do things like write device drivers for OS X, but I'm not sure I've heard of anyone using it as a desktop or a server (I mean aside from an OS X machine). So while you may be able to grab it and use it, if you want a server or a free UNIX-like desktop you may as well just go with a Linux distro or a BSD.
I mean, I'd be interested to hear if anyone uses OpenDarwin (or one of the variants) regularly, but it seems like for most things there's not much point.
Yeah, I have an Octane II. I don't browse the Web on it, but from time to time I use it for some graphics work. Namely, Photoshop 3 came with it. It still runs beautifully. When I'm not doing that I use it as a foot stool or as reinforcement for the pile of papers and other stuff in my work area. It's a very sturdy machine.
Coal is wood from the past, you know, wood which is made out of Carbon that didn't get released into the atmosphere.
Yes, coal is indeed wood (and other organic matter) from the past, as is oil. The very distant past. It was once part of the carbon cycle, but after getting buried and compressed (and thus formed into coal/oil) the carbon cycle in the atmosphere gradually worked around it (over millions of years). So digging it up and burning it puts that back into the current atmosphere and carbon cycle, which could cause problems. IE, I don't expect the trees to get re-sequestered like the ones that became fossil fuels back in the day.
On the other hand, I guess it would be possible that by planting all the trees you would help the carbon cycle adapt to the increased carbon. Again I'm not sure, but I suppose planting more trees would be a good thing even if it doesn't completely solve the problem.
I've never a post explaining why they are not real.
I'm not totally sure, but I would imagine it would be something like this: When you burn a fossil fuel, you're taking carbon that was sequestered in the ground and reintroducing it into the natural carbon cycle, thus throwing things off (eg, climate change). Now, if the carbon credits work by having some company agree to plant enough trees to absorb a certain amount of carbon (say the equivalent to the round trip flight to Tahiti), the trees will in absorb it, but the carbon hasn't actually been taken out of the cycle. IE, they will die or get eaten by something, and the carbon will still get released into the atmosphere eventually.
On the other hand, if the credits work by using some renewable source to displace carbon that would otherwise be released from fossil fuels (for instance if a company agreed to generate a certain amount of electricity from solar and pump it into the grid; again I'm not completely familiar and am taking a stab), then in theory there would be some benefit. But then you could just cut out the middleman and not take your flight or your long drive or whatever.