Heating and Cooling

Heating

I think we're going to use a hydronic underfloor radiant heat system. Underfloor radiant heat is supposed to be considerably more efficient than forced air, because it provides better heat distribution. As the image shows, forced air heats rooms unevenly, and the hot air tends to accumulate at the ceilings, particularly in homes with high ceilings. I'm not sure the image is completely accurate; other resources I find on the web indicate that heat still accumulates near the ceiling, which makes a lot more sense thermodynamically than what the image shows.

However, radiant floor systems do produce a much smaller difference in heat between ceiling and floor. While forced air systems often have 15+-degree differences between the cool floor areas away from heat registers and high points in ceilings, radiant systems generally see no more than 2-4 degrees difference. This makes radiant heat systems more efficient, since you're not overheating one area in order to achieve a comfortable temperature elsewhere.

They're also, by all accounts, simply more comfortable. Since the heat comes from below, radiant head means that your feet will be warm. I tend to have problems with perpetually-cold feet, so that sounds really nice to me. Plus, imagine never stepping onto a cold floor in winter time!

Cooling

For cooling, hydronic floor systems are also useful, but only to a limited degree. Cooling the floors below about 68 degrees is said to cause in-floor condensation, which is bad. I'm not sure that is as great a problem in Utah, given how dry the Rocky Mountain air is, but it's probably a good guideline. Still, hydronic radiant systems can do a great deal to cool a home as long as the air temperatures don't get too high. Given that Morgan isn't that hot in the summer, and given that the air cools down significantly at night, I think we may actually be able to avoid using air conditioning most, if not all, of the time.

A key component of making summer cooling work well is another high-tech element I'm planning: automated windows.

Linear chain-drive motors like the one shown above cost about $200 each, but should last for decades with no maintenance, and are easy to integrate into a home automation system. My theory is that if I can reliably open the windows in the summer evenings, as soon as outdoor temperatures drop below indoor temperatures (assuming indoor temps aren't already too low), then we should be able to cool the air and all surfaces inside the house each evening. Combined with the cool floors -- particularly with floors that have high thermal mass (more on that in a bit), we should be able to have comfortable temperatures throughout the bulk of the day.

Insulation

Of course, a key to keeping the house comfortable year-round, inexpensively, will be insulation. Based on my research, I think we want to shoot for wall insulation factors around R-30, with a bit more in the ceiling, about R-50. In practice it appears there is very little difference between R-30 and R-40, or higher.

Windows

The hard part of insulation, though, is the windows. And we have lots of windows. Big windows. Kristanne likes windows. In particular the great room has windows 13' long and 18' high. That's 234 square feet of window, which is going to lose a lot of heat in the winter and will also produce significant solar heating in the summer. Even the most efficient triple-pane, argon/krypton-filled windows are only about R-6.

The insolation (solar heating) factor will be reduced by the fact that the window is facing northwest, and there is also a mountain range nearby to the west, which reduces the duration of direct sunlight. An open question is whether we should get high, medium or low solar heat gain coefficient (SHGC) windows. SHGC is a measure of how much solar heat and visible light the windows allow to pass through. Low solar gain (LSG) windows have multiple layers of reflecting films that reduce the amount of solar energy that passes through.

Medium Solar Gain Windows

I think we probably want low or medium-gain windows. It would be attractive to use HSG windows to get a little solar heat during the winter, but I don't think we'll get any significant amount of direct sun to the big windows in the winter.

Unrelated to heating and cooling, there's one other thing I'd really like to do with a lot of our windows, if we can: get German-style tilt-and-turn windows. If you've never seen them, they're awesome.

I don't know how available they're going to be in the US, or what they'll cost, though.

Heating Zones

I originally thought I wanted to have per-room heating zones. Basically, each zone in a radiant system consists of a thermostat, a pump and a set of in-floor tubes. My theory was that per-room zones would provide great flexibility, but everything I read says that small zones just add cost and complexity without really making that much difference. Radiant heat is slow and pervasive so you can't really do things like focusing the heating on the areas where people are.

What does make sense is to separate out zones that may need more or less heat on a longer-term basis, such as rarely-used guest rooms (which we don't have), or areas which need more heat input because they experience more heat loss, like rooms with lots of glass. That we do have.

So I think we'll mostly do just one zone per floor, but with the great room as a separate zone, and probably a zone for the master suite, mainly because of the sun room which has the potential to be a heat-sucking area in winter.

Energy

Saving the most interesting for last, a really important question is what energy source will be used to heat (and maybe cool) the hydraulic fluid? There are lots of options. In fact that's a great thing about radiant; any approach you can think of to heat or cool water can be used. Some options:

• Electricity (heat/cool)
• Heating oil (heat only)
• Natural gas (heat only)
• Solar (heat only, unless it's photovoltaic, which means electricity)
• Geothermal ground loop (heat/cool)

Further, it is even theoretically possible to use multiple energy sources, mixing and matching as appropriate. For example, you could use solar to pre-heat the water that goes into a gas-powered boiler.

I need to see what the costs will be but I'm leaning strongly towards a geothermal ground loop as the primary source. I'm not a green freak, but I really like the idea of drawing most of the heating / cooling energy from the ground, which means ultimately from the sun. There are some electric water pumps that have to be run, and an electric heat pump, but even though electricity is far more expensive than, for example, natural gas. From what I read, return on investment is generally pretty good, only a 4-8 years, assuming you are already spending on a radiant system.

If it's not geothermal, I think I'll probably want to go with a gas-fired boiler (or high-efficiency water heater), plus maybe some solar pre-heating. With that approach, I'm not sure how you'd do cooling. I need to do more research. I'll follow up with another post when I know more about that.

Re-activating this blog and new house design

This blog has been completely dormant for quite a while, but I now have something interesting to post about, and I expect there to be a lot of posts coming. I'm building a new house, which is somewhat interesting, but I'm also planning to incorporate a lot of custom-built automation into it and I think that's very interesting, and may be interesting to others. Particularly since I'm new to electronics engineering, so I'm going to be posting what I learn as I go.

Today, though, I just want to talk about the house as a whole. My uncle Kelly is doing the architectural design and he has finished the basic plans and is sending it out for structural engineering review, so it's pretty close to final. For those who've followed my Google+ posts, this will be old news. I'll get into other, more interesting stuff soon, but I want this blog to have a fairly complete record.

First, this is the front view and the view from the right end (as you face the house):

The left side of the house is the garage. The tower contains the stairs going up and down. The small sections on the ends with the archways are facades.

Next, this is the rear view and the view from the left end:

That's a two-car garage, but an extra deep one. We decided that two cars is enough, because we'll also have a large (approximately 30' x 40') shed on the property where we can keep equipment. The extra depth of the garage will leave plenty of space for tools and even a small workshop area in front of the cars. I may have a bigger workshop in the shed.

The big windows near the center of the house open into the great room, which is two stories high. To the left of it (in this image) there's a sun room that projects back from the master bedroom. To the right is the kitchen/dining area, which has a bay window.

Here's the main floor:

At the bottom of the plan is the entrance. You can see the covered area leading to the double doors. Just inside the doors to the right is a half bath. Straight ahead from the doors is the great room, with its 18 foot-high windows and a door opening onto the back patio. To the left of the entrance is the stairs going down to the basement and up to the second floor. Also to the left is the kitchen and dining area. I'll detail the kitchen design in another post. Beyond the kitchen are a mud room, laundry room and pantry. The mud room connects to the garage which will, of course, be the primary way that we enter and exit.

To the far right is the master bedroom and bath. The bedroom opens into a sun room in the rear, perhaps with a half wall dividing them. The master bath is large and comfortable and opens into a big walk-in closet. Note that the closet connects to the bath, not the bedroom. That's so if one of us is up earlier than the other (or later), that person can bathe and dress without bothering the other.

Here's the upstairs:

To the left are two bedrooms, each with its own features. The one on the end is larger, with a walk-in closet and a door (not shown) into the "bonus room", which is space carved out of the garage attic, for storage. The one next to it isn't as big, but has a nice bay window, with a window seat. There's a full bathroom next to the two rooms. One other feature of this area is that the hallway into the smaller room will have a laundry chute, which opens into the laundry room below.

In the center is the great room, which is open to the floor below, but with a walkway stretching across to the right. On the right end there is a guest bedroom, with connected full bath, and my home office which also connects to the guest bath.

Next, the basement:

The basement will be unfinished, mostly. In the front, underneath the front porch, will be a cold storage room, for food storage that needs cooler temperatures. To the right and further back is the utility room. I have great plans for that utility room, more in future posts. There's a location for a bedroom to the right, with a large window. The left and rear is a basement walkout, with lots of space for bringing in large furniture. Eventually we'll build a family room / home theater down here, but not right away.

Finally, the location:

The blue quadrilateral is the property boundaries. The lot is five acres. The black curving line is the driveway. The reason for running it back so far and then curving around is because there's a hill, and that route provides a gentle grade to the top. The red polygon is, roughly, the edges of the hilltop.

The larger black rectangle is the approximate size and location of the house, sitting on top of the hill. The house will fact to the southeast (north is up). This means all of our big windows will be pointing to the northwest, which is a little unfortunate. The smaller black rectangle is our planned storage shed (which will be built well before the house). The placemarker balloon is the approximate location of the planned well, which needs to be at least 100 feet from any building and from the property line.

Technically, the well doesn't have to be 100 feet from the property line, it just has to be 100 feet from another well. But if you put it close to the property line you have to get an easement from the owner of the neighboring land, which is basically a commitment from them that they'll never put a well on their property within 100 feet of your well. The easy way to avoid all of that is just to put it at least 100 feet from the property line.

Not shown on this image is that the septic tank and drainage field will be between the house and the road, in the low ground (which looks very green in this image).

Web site password manager

If you're like most people, you use a bunch of different web sites, including some that handle some pretty important stuff -- like money -- but you use the same password for all of them. And it's probably not a very strong password, either.

That's a really bad idea. If one of those sites gets hacked, the attacker could get your password and then start trying other places it might work. Essentially, the security of all of your web accounts is only as strong as the weakest one.

But the reason we do that is because it's just danged hard to remember a whole bunch of different passwords. I'm hopeful that eventually OpenID will solve this problem but in the meantime I found another nice solution: Passpack.com.

It allows you to store all of your passwords in one place, and it even provides a little button you drag onto your bookmarks that automagically types the right password for each web site you visit. So, I've now gotten rid of my one password for everything and replaced it with a bunch of passwords, one for each web site I use -- and I never have to actually type any of them. I just go to, for example, "discovercard.com", then click the "Passpack it" bookmark and I'm automatically logged in. And the password is something like 3yPtdkogzh8H, which I could never remember, but don't have to. Or even something like "ò-èuÓ¿¸>8ÝAÖ" for sites that can accept the strange characters -- I don't have to type it so there's no reason to limit it to something I can type.

This *also* works from any computer that has a web browser. I do have to remember my "passpack key", which is what secures all the rest of my passwords, but as long as I know that, I can log into passpack from anywhere and then use it to log into other web sites. Do be cautious about using passpack from public computers, though... there are ways that a deeply hacked computer could extract your passwords if you unlocked them while using it.

Finally, I also had Kristanne set up a passpack.com account, and then I "shared" my passwords with her. So she can use them to log into web sites, too, so that we both have access to our bank account, credit card accounts, etc. If I ever change the password for one of them, I just update it in passpack and then when she uses it to log in she'll get the right one -- and won't even know that it changed because she never sees or types the passwords.

How all of this works is pretty complex, and very technical. Suffice it to say that it appears to be done right from a security perspective. Your passwords and your passpack key are never sent to passpack.com in "plaintext". Software running in your browser applies a salted secure cryptographic hash function to your passpack key to produce a 128-bit AES key which is then used to encrypt your passwords. The encrypted passwords are sent to passpack.com and stored there (which is how it can work from a browser on any computer -- they encrypted copies are downloaded). Password sharing is done by generating a 1024-bit RSA key pair which is used to exchange AES session keys to make it possible for people you share your passwords with to use them. Actually, you can also use the sharing service as a form of highly-secure e-mail.

If the preceding paragraph is gobbledygook, just trust me. Or if you'd like to understand it, just ask sometime and I'll explain it in as much detail as you could possibly want :-)

If that paragraph isn't gobbledygook to you, and you see a bunch of possible holes, that's because I left out all of the details.

Won't people freak out and call the police if I openly carry a gun?

Short answer: It's possible, but not common.

Utah is a very gun-friendly state, and many residents of Utah have some familiarity with guns. In addition to that, people tend to assume that the calm, confident actions of a normal-looking person must be legal and most people are, frankly, oblivious to most of what goes on around them.

These factors combine to mean that open carriers find that the vast majority of people simply don't notice the gun, especially if it's not large or ostentatious, the majority of people who do notice the gun don't react to it and most of those who react ask questions or make comments rather than calling the police. People who open carry regularly report that the most common interactions are very positive ones, where the carrier has an opportunity to explain the issues to the curious or just engage in “gun talk”, chatting about shooting, firearms and lawful self-defense.

That said, negative interactions do ocasionally occur. Most often these take the form of store or restaurant employees asking the open carrier to leave. Sometimes these requests are provoked by questions from other customers but most often they are initiated by employees. The appropriate response of the open carrier to such a request is not to argue or debate the point, but simply to comply, ideally without completing a purchase and with a followup letter or e-mail to explain the carrier's point of view and to request clarification of the store policy.

In rare cases the police are called and become involved. In some areas, 911 operators are being trained to question “person with a gun” reports, asking what the person is doing, if he or she is threatening anyone, etc. In those areas, police are unlikely to be dispatched. If police do arrive, interactions are generally peaceful, though not all police officers are fully informed on the law so some may make false statements regarding the legality of open carry. If you are the recipient of police attention due to open carry, please stay calm, stay polite and if the officer is making incorrect statements, just say “I'm sorry officer, but I don't think that's correct. Can you please ask your supervisor to verify it?”.

If you are a person who has an unusual style of dress, hairstyle or appearance, especially if your appearance is one that might be associated with gang or criminal activity by many people, or if you appear or act intimidating or frightening even without a firearm, you are much more likely to have negative interactions and police interactions as a result of open carrying. This may not be fair or right, but it is reality. Also, young people and those who engage in body modification (piercings, tattoos) are more likely to have negative experiences with open carry. In contrast, well-dressed, well-groomed, responsible-appearing people tend to have no issues.

I don't have a concealed carry permit, can I carry a gun?

It is legal to carry a firearm in Utah without a permit, but there are some things to watch out for if you leave your own property or vehicle. Specifically, if you're carrying in public your firearm must be unloaded and unconcealed, and you must avoid school zones and buses or trains.

It might seem that carrying an unloaded gun is useless, but Utah's law has a peculiar definition of the word “loaded”. Specifically, the law says that gun is loaded if either:

1. There is a round in firing position; or
2. A single mechanical action will cause the gun to fire.

This means that you can carry a semi-automatic with a full magazine as long as the chamber is empty, because an empty chamber means there is no round in firing position, and it takes two mechanical actions to fire the gun: rack the slide and pull the trigger. For a revolver, the chamber lined up with the barrel must be empty, and if the revolver is double-action, meaning a pull of the trigger will rotate the next chamber into position, cock the hammer and fire the gun, then the next chamber must be empty as well.

In contrast to this odd definition of “loaded”, Utah's definition of “concealed” is very straightforward. A gun, or any other dangerous weapon, is concealed if it is hidden so that people aren't aware of it but it is readily accessible. In practice, the best way to open carry is to use a normal outside-the-waistband belt holster. I recommend using a holster that has some “retention” features, which are devices that lock the gun into place so it can't easily be removed by someone who isn't familiar with the holster, and I recommend practicing techniques to stop a gun grab attempt.  Such attempts are extremely rare, but your gun is your responsibility so it makes sense to be prepared.

The final issue to watch out for is locations where it's illegal for you to carry. The most frequently-encountered issue is school zones, but carry is also banned on UTA buses and trains and in bus and train stations. There are other areas that are off-limits even for permit holders, including courthouses, jails, secure areas of airports, etc.

Without a permit, it is illegal for you to carry within 1000 feet of any school property, where “school” means any pre-school, day-care, elementary, secondary, or post-secondary institution. Since day care facilities are often ordinary homes with no distinguishing marks, and post-secondary schools like cosmetology schools and massage therapy schools are found in many strip malls and may not look like schools at all, this means there are a lot of places that carry without a permit is illegal. The area within 1000 feet of a school-sponsored activity is also considered a school zone.

If it weren't for some exceptions in the law, school zones would make lawful unlicensed carry almost impossible, and would pose serious problems for owners of homes and businesses near schools. First, it is legal to possess a firearm on private property located within a school zone, with the owner's permission. Second, it is legal to possess a firearm in a vehicle located within a school zone, with the driver's permission -- as long as federal law enforcement isn't involved. The federal school zone law allows firearms in vehicles, but only if the gun is completely unloaded and in a locked container. This law has never been enforced since it was passed in 1995, but it is on the books.

Relevant laws:

• UCA 76-10-505 bans carrying a loaded weapon on a public street. Note that the law does not define “public street”, so to be safe I recommend interpreting it as “anywhere but private property with the permission of the owner”.
• UCA 76-10-502 defines when a weapon is deemed loaded.
• UCA 76-10-504 bans carrying a concealed dangerous weapon.
• UCA 76-10-501 defines “dangerous weapon” in paragraph (6), “concealed” in paragraph (3) and “readily accessible for immediate use” in paragraph (15).
• UCA 76-10-505.5 is the state law that bans carrying a dangerous weapon (including firearms, per 76-10-501(6)) in a school zone.
• 18 USC 922(q) is the federal law that bans carrying a firearm in a school zone.
• UCA 76-10-1504 and UCA 76-10-1507 ban carrying a firearm on a bus or in a bus terminal.
• UCA 76-10-1503 defines “bus” to include any transit vehicle, including trains like TRAX and FrontRunner.

There's going to be an increase of activity here

I need to get my utahlegalcarry.com site up and running soon, but in the meantime I've decided to start posting here some of the content that I ultimately want to put there.  Eventually I want to build a fairly comprehensive FAQ list for people who want to understand legal carry of firearms and other dangerous weapons in Utah.  To begin with, I'm going to start posting essays on various topics here, with the intent that they'll eventually get incorporated into my FAQ list, and so that in the meantime I can easily refer people to them.

I'm going to shoot for adding one or two articles per day here, so expect to see some activity.

Here's a partial list of issues/questions I'm going to address:

• Politics/opinion (note:  I'll give my opinions, but try to present all sides)
• Shouldn't only police officers have guns?
• Isn't it a bad idea to allow anyone who wants to carry a deadly weapon?
• Doesn't allowing people to carry guns at our schools endanger the children?
• Doesn't owning, possessing or carrying a gun make you more likely to get shot?
• Why would anyone want to carry a gun?
• Why would anyone want to carry a gun openly, if they can conceal it?
• Legalities of carrying a firearm or dangerous weapon
• I don't have a concealed carry permit, can I carry a gun?
• I have a concealed carry permit, where can I carry?
• How come Utah courtrooms don't provide firearm storage lockers, like the law says they should?
• I have a concealed carry permit, does my gun have to be hidden?
• Can my city or county ban dangerous weapons?
• I'm a student or staff member at a Utah university, can I carry there?
• My employer has a policy against carrying weapons at work.  Do I have to obey that policy?  What might happen if I don't?
• What kinds of weapons does a Utah Concealed Firearm Permit allow me to carry?  How many can I carry?
• What should I do if I see a "No Firearms" sign somewhere?
• Can I carry in other states?  If so, which ones and what are the rules?
• Can I take my gun on a plane?  A train? A bus?
• Practical issues around daily carry
• What kind of gun should I get?
• What caliber is best?
• Are revolvers better than semi-automatics?
• What brand of gun is the best?
• Are big guns better than small guns?
• Is it important to use a holster?
• What kind of holster should I use?
• Should I use a lot of different holsters?
• What should I do with my gun when I go to the bathroom?
• If I'm pulled over by the police and I have a gun, do I have to tell the officer, and if so how should I do it?
• Firearm safety
• What's the difference between an accidental discharge and a negligent discharge?
• How can I make sure that my guns don't hurt anyone?
• How can I make sure that my guns aren't a danger to my children?
• Are there any special safety precautions I should take while carrying?
• Is it safe to carry a gun with a round in the chamber?
• Securing firearms
• Am I responsible for keeping my guns secure?
• How can I secure them in my home?
• How can I secure them in my car?
• How can I secure them when I travel on airplanes or trains?
• Training
• How much training do I really need?  Isn't the Concealed Firearm Permit course enough?
• What kinds of training are available for free?
• What kinds of training are available for fee?
• Legality of self-defense
• Who am I allowed to defend?
• When is it legal to shoot someone?
• On the street
• At home
• In my car
• On my property
• Do I have to try to escape before I can defend myself?
• When should I shoot someone?
• When should I NOT shoot someone?
• Should I threaten someone with my gun?  Should I draw if I'm not planning to shoot?
• Is it necessary to carry a non-lethal defensive tool, like pepper spray?
• If I get in some sort of altercation that doesn't involve my gun, should I call the police?
• If I get in some sort of altercation that does involve my gun, but I don't shoot anyone, should I call the police?
• If I shoot someone, what should I do next?
• What should I do before I call 911?
• What should I say to the 911 operator?
• What should I do while waiting for the police to arrive? 
• What should I do when the police arrive?
• What should I say to the police?
• Will I be arrested?  If I am, what should I do?
• Can I be sued even if the police decide I didn't commit a crime?
• Utah's Concealed Firearm Permit
• Who is eligible to get a permit?
• What records does the state examine to determine eligibility?
• What's the process for getting a permit?
• How much does it cost?
• How long does it take?
• What are the steps?
• Can I get a temporary permit quickly if I'm in danger?
• How long is the permit good for?
• What is the process for renewing a permit?
• What kinds of things might cause my permit to be suspended or revoked?

I'm sure plenty more stuff will come up as I flesh this out.  I'm going to attempt to use the newspaper article structure for each answer, meaning that the article provides the basics first then incrementally expands the details, so the reader can stop at any point.

Awesome new voting system used in Maryland

I'm something of an election geek. I deeply believe that although democracy sucks (including the slightly-less-sucky Republican variant we use), it sucks less than any other system of government. But to make any Democratic system work there must be a good way to determine the will of the people, and that turns out to be very hard to do.

There are two main parts to the hardness. First supposing you can collect everyone's opinions, how do you put them together to make decisions? We generally use the "plurality rules" system; whichever option gets the largest number of votes wins. That system is full of problems, but that's not the subject of this post.

The other problem is collecting everyone's opinions and doing it accurately. Someone who can manipulate the elections has tremendous power, and there are a LOT of ways of manipulating elections. Stalin famously (and apocryphally) said "Those who cast the votes decide nothing; those who count the votes decide everything," and historically that is the BEST way to manipulate an election. Let the people vote as they will and then either just report whatever result you want or, if you're more subtle, just tweak the counts enough to give the desired outcome.

In the US we've recently gone through a somewhat mind-boggling electoral change by deploying electronic voting machines. I say mind-boggling, because these machines are the PERFECT tool to facilitate large scale, undetectable election fraud, and supposedly we're a country that takes its elections very seriously.

If the idea that electronic voting machines are a bad idea strikes you as surprising, or the view of a Luddite, let me point out that I'm a professional software engineer with a career focus on building extremely high security systems. If you wanted to build a very secure electronic voting system, I'm the kind of person you'd hire to do it -- and I would tell you that it is a TERRIBLE idea. And not just me. A few years ago, as the debate was just starting to heat up, several hundred of the world's top computer security experts collaborated on and signed a paper which basically said the same thing. They explained in detail why computer security technology at present and for the foreseeable future was simply not up to the task. The very best in the world said, in effect, "Not only don't we know how to make such a system secure, we really doubt that it's even possible."

By the way, the system that Utah uses is the worst of the worst.

This debate, however, did provoke a bunch of top-flight cryptographers, mathematicians and computer scientists to start thinking hard about how to design an election system that is secure against fraud. They wanted to build something that cannot be manipulated by the people in power without the populace being able to detect it, and which also preserved the anonymity of voters. It's very easy to build a secure voting scheme if you don't mind revealing who everyone voted for, but that enables vote-buying and coercion.

Some very cool ideas were developed, notably originating from Ron Rivest (who is the "R" in "RSA", for those who know what RSA is) and David Chaum (the creator of some very cool untraceable digital cash schemes). It's probably unfair to mention only their names, because there were many contributors, but they were the main "well-known" researchers involved. The first versions of these ideas were theoretically very cool, but completely impractical. Lots and lots of academic security ideas start out exactly that way.

A few years ago, some of the disparate ideas started to come together, along with some refinements that made them more practical. The result was a system called "Punchscan", which was used to carry out some real-world elections for university student body leadership. It was a good test environment because the stakes were relatively low, but the scale was big enough to make the test realistic. A system that works for a few hundred people is a lot different from one that works for tens of thousands, and once you get to that level it's really not that different to scale it up to millions.

The third-generation successor of Punchscan, called Scantegrity II, was used on Tuesday to carry out the municipal elections in Takoma Park, Maryland. This marks the first time these new ideas in election integrity and verification have been applied to a real government election. And it worked well. The security experts said that electronic voting machines were a bad idea, and now their recommended alternative was used for the first time.

The basic goal of the system is to ensure that it is impossible for ballots to be lost or modified undetectably, and to do it in the context of a practical election that is cost-effective, easy to run and easy for voters to use.

It uses optical-scan ballots, with a small twist. The "bubbles" on the ballot are pre-filled with invisible ink. The voter has a marker that contains the chemical that activates the ink, so swiping the marker across the bubble causes it to be visibly filled -- mostly. When the ink is activated, not only is the bubble-filling ink revealed, but a three-letter code is also revealed. The code is "printed" by the absence of the ink.

A voter who wishes to make sure that his ballot is counted correctly takes a moment while in the voting booth and copies down that three-letter code, as well as the ballot serial number. After election results have been posted, he then goes to the election web site, types in his ballot serial number (which isn't associated anywhere with his identity), and make sure that the codes he copied down are among a small list of codes presented to him. If they are, then he knows his ballot was submitted and tallied as part of the final count.

Now, HOW that code's presence on the web site verifies that the ballot was counted correctly is a little bit complicated, and I'm not even going to try to explain it here. If you want to know, a good starting point is this paper. Also, that code-verification is far from the only thing that has to be done to verify the integrity of the election. Ballots have to be audited before and during the election (audited ballots are not used to cast actual votes), there's a pre-election "code commitment" process that the election officials use, and a post-election "randomized partial checking" system that verifies that the ballots submitted and tallied were actually tallied correctly.

The system allows all of these various integrity verification processes to be carried out by ANY interested parties. It's presumed that the candidates and political parties will take part in them, and that democracy watchdog groups will as well, but any interested person can do it. In fact, the system is designed so that anyone who wants to can easily conduct a personal recount of the entire election, just by downloading the data over the Internet and then running some software on it. The software has to do some complex things, including a lot of fancy math, but the detailed specification for what the software must do is available, along with mathematical proofs demonstrating how it assures integrity, so that anyone with the relevant skills can write their own software to do the verification. Those who don't have the skills to write the software just need to get a program from an organization they trust, and use that.

All of this makes it possible to prove to an arbitrary mathematical probability that the election results were accurate. By "arbitrary mathematical probability" I mean that there is always a possibility that the election was fraudulent and that the fraud was undetected, but for any given margin of error you can decide how much auditing needs to be done to make the probability of fraud as small as you want it to be. The smaller you want to make it, the more auditing is required, but you can achieve any desired level of certainty.

In addition, the Scantegrity system allows for manual recounts of the paper ballots. Manual recounts are actually less reliable than the statistical verification the system uses, but they're an option, unlike with electronic voting systems (including Utah's; no one has ever managed to successfuly recount an election from those paper rolls the machines produce).

This is very cool stuff. Of course it doesn't address issues with registration fairness, fraud, etc., or issues with whether or not plurality voting makes sense, and certainly does nothing to address voter apathy, lying politicians, media influence or any of the many other problems with the political process, but it DOES allow us to have confidence that our votes are counted as cast, which is something that has never been very certain, and which the current generation of voting machines has made very, very questionable.