Wesley's Tool-Box

It's been about five months since I installed Seojun Smart Meter at home and took various measures to cut down unnecessary electricity use. Now was a good time to see if the smart meter was recording monthly data accurately, and whether my efforts panned out well. This graph sums up everything that needs to be said.

In terms of accuracy, the smart meter consistently reported slightly lower than the default meter installed in the premise. However, it is more less in line with the advertised margin of error (1%) after the initial month and thus I think it's reliable. This is important because the companion app effectively shows last month's finalized data a full month before it shows up in the bill, and the app also shows the forecast for this month. Now I know that these values can be trusted and I can prepare two months ahead.

Moving onto the consumption trends, my home generally spent around 190 to 200kWh in winter, then fell down to the 170kWh range in spring if the family didn't go out on a vacation. This is already somewhat below average for a 4-person family, but I started making the house even less wasteful starting in February this year by making more efficient use of the appliances and changing the lightings and bulbs to LED. Eventually, it has settled to somewhere between 140 to 150kWh per month now. This is a saving of roughly 30kWh, or more than 15%.

Thanks to this and being much more aware of the consumption in real time, I'm expecting about 30% savings in electricity costs in the summer when the air conditioning is in full operation. Home electricity rates in Korea is pseudo-exponential, so you pay a lot less for seasonal increase if you start out from a lower baseline. Recently, I helped my dad cut down power use at his house by lowering the baseline by roughly 200kWh and I think it'll save him at least US$300 per month during summer. I'm expecting that the money that went into the streamlining will pay for itself in 3 years. Overall, I'm satisfied with the results of the efforts I put in.

It's now been one full year since I started wearing Apple Watch Sport and now is a good time to give you an update. I have been wearing it all the time except when it needs to be charged, so it has been through a lot. Daily showers and occasional swimming sessions may have caused a bit of degradation on the left edge of the screen, and an encounter with a rough surface left the glass with noticeable scratch lines. Despite all this, it's holding up well and functioning normally. I'll probably send the device in for replacement using AppleCare+ after I buy the next version, though.

In terms of battery life, it has consistently delivered at least 24 hours of use for me, except during early watchOS 2.0 betas. So I'm now accustomed to about 22 hours of use (with about 10 to 30% left as I take it off) and 2 hours of charging. The only times I wish the battery life was longer is when I do long-distance travelling, where the active time might stretch beyond 30 hours.

As for its uses, I've settled on the watch mainly being a quick notification-response device and a fitness tracker. Those two functions currently work fairly well. Meanwhile, the native app support with watchOS 2 has been hampered with the relatively slow performance. It often makes me want to reach for my iPhone instead of loading the relevant app on the watch. This needs to be addressed in the near future if Apple Watch is to be taken seriously beyond being an "accessory."

Now, the fitness tracker part of the watch was something I was looking forward to when I bought it. I have lost weight through exercise before, but lack of reminders once the goal was reached resulted in regaining some of that weight after a few months. So I decided to make good use of Apple Watch to keep me stay fit. I made sure to reach the daily Move goal every day, which had been set to 450 kcal after the first month. Missing this goal only a couple of times, I was able to earn the "365" badge you see above two days ago. Let's see the activity and weight trends in detail.


Why did I choose the 450 kcal mark? This is generally about 200 kcal more than I would normally burn through a normal day. 50 minutes of walking or 20 minutes of jogging can fill that in - these activities can easily blend into the daily routine and also conveniently make me reach the 30-minute Exercise goal in the process. Basically, I can get the bare minimum amount of exercise that Apple Watch recommends via its three-ring system with that setting. The graph evidently shows that I don't actively seek out to go beyond this goal unless something else is going on, like when I'm traveling. Some of the big spikes correlate to my overseas trips - New Zealand in May (2015), UK in July, and Japan in September, to name a few.

As a side note, the data for the resting calories starts on July 9 because this is when watchOS 2.0 beta 3 came out and made Apple Watch start recording this data on iPhone's Health database. Before that, the data resided only within the Activity app, likely because it was rudimentary and static, not to mention less accurate - it was about 40 to 50% more than expected. Since the update, the resting calories data is recorded in real time and seems to be more in line with the mainstream calculations.

Interestingly, I noticed that just reaching the Move and Exercise goals wasn't doing a particularly good job of shedding the weight in the early months. I did have a weight scale and occasionally checked my weight with it, but it hovered between 83 and 84kg without any upward or downward trend during that time. Besides, I never got around to recording the data anyway. The only data point during the period was from the annual check-up at my workplace. I decided to do something about it and got myself a so-called "smart scale" with Bluetooth connectivity in August.

Nearly a decade ago, you would have seen me wearing all sorts of gadgets around my waist, as evidenced by this television broadcast. The problem with this was clearly illustrated in that video - it takes a bit of time to put them all on the belt, however useful they may be.

I haven't let go of the carry-them-all attitude, but things have worked in my favour. A lot of the gadgets I had to carry separately were now integrated into a single device (smartphone). That meant less stuff to carry, and I was able to reduce the number of pouches and bags on the belt over the years. I ended up with a phone and an external battery each in a holster, and a bag that held adapters, cables, and other miscellany.


But then large iPhones came along. When I put it on my belt, it occupied a sizable area of my waist. This got me thinking: since the phone is thin enough, maybe I could put it in a belt bag that can store other stuff with it. And this is how I now just have this one bag hanging from my waist.

As you can see here, my iPhone 6S Plus and the slim external battery fit nicely into the front pockets of the bag. They're accessible by opening up the flap usually held in place with a hook-and-loop fastener. I also have a paper clip there in case I need to change the SIM card or poke a reset button.

Of course, there's a lot more hiding behind. Let's take a look at the rear compartment.

A few months ago, I noticed that the first generation FLIR One thermal imaging module for iPhone 5 & 5S went on a bargain sale online for about US$110. Since the newer version and the competing products were two to three times more expensive I thought it would be a great chance to own a thermal imaging camera of my own and ordered one. Good thing I did, because as of this writing the price went back up so high that you'd be better off getting the newer version.

Mine arrived after a couple of weeks and I was already impressed with the nifty packaging. The product itself was also well-built and tightly integrated with my iPhone 5 once I put it into the provided case. Functionally, it works pretty much as advertised. You can see the thermal images of your environment through the phone's screen, with objects' contours enhanced using the images from a regular camera next to the thermal one. This technique, called MSX, is a way of mitigating a relatively low pixel count of the sensor (80 x 60 = 4,800). You have to recalibrate the sensor from time to time using a sliding switch next to it, which is slightly inconvenient at times.


Other device specifications limit the use of this module mostly to indoor use. The maximum range is about 30m (100 feet) and can only detect between 0°C to 100°C (32°F - 212°F). It does work quite well if you work within these limits, though. I can see where the heat leaks in my house and whether the floor heating is working properly, to give some examples.

To me, the fact that it works only with iPhone 5 or 5S out of the box was its biggest disadvantage because the larger iPhone 6 and 6 Plus series came out just two months after its official availability. FLIR did address this problem by releasing a second generation model a year later that solved the form factor problem (just plugs into the bottom of a phone) along with an upgraded pixel count (160 x 120 = 19,200) and range (-20°C to 120°C). It also does auto-calibration, boosting its convenience. But what about for those who already own one and upgraded to the newer iPhones?

You could use it on a spare iPhone, like I initially did, or modify it. There are aftermarket phone cases to fit an iPhone 6(S) or 6(S) Plus. But these require you to cut off the curved area to the side of the connector on the module so that they won't interfere with the wider width of these phones. Otherwise, the Lightning connector wouldn't go all the way in. But I did not like to mutilate it like this and decided to find another way.

As the hunt for even more potential waste of power continued, I brought in the help of thermal imaging technology. By scanning each place with a thermographic camera attached to an iPhone (FLIR One; I'll write about this later) I can find any hot or cold spots that seem to be out of place.

One of such "hot" spots I found was on the side of an air conditioning unit. It wasn't being used, but standby power drawn from the wall outlet was slightly heating up the control circuit and was readily visible via thermal images. I could just pull the plug until summer, but I decided to take a step further.


I replaced the default wall outlet with the one that had an integrated switch. This way, I could cut the power from the outlet with a switch when the air conditioner isn't in use, instead of having to pull the plug. Not only would this be simple to operate, it would avoid the mechanical wear. I should have done this ages ago.

As part of my ongoing data collection, I then tried to measure how much power the air conditioners in the house would consume while trying to cool the house. Sadly, the rooms were not hot enough for them to start cooling the air. I'll have to check them out again when summer comes.