Posts on Invisible Parade

Analyzing home energy usage with AI

2026-08-31T16:11:00+09:00

My house has the following features:

Solar panels on the roof. These were heavily subsidized and on a 10-year lease, so excess electricity is taken by the power company for the first 10 years. After that, I can export it for profit (although I expect prices to keep falling).
An ENE-FARM, a fuel cell that uses natural gas to generate electricity, using that heat to produce hot water.

The solar panels are great. They generate more than we need during the day on most days, and have really brought our electricity bill down.

The ENE-FARM came with the solar panels as part of the subsidy package. It’s a fascinating device, the idea being that gas prices are generally lower than electricity prices, and you can save some money especially since you can use that hot water. But in our experience, it felt like the residual cost of having it on increased gas prices more than it decreased electricity prices, so we have turned the generation off and are using it just like a normal water heater.

I was about 80% convinced that we were using these appliances in the most cost-effective way, but recently was able to use AI tools to actually do the math.

Getting the data

All energy usage goes through the fuel cell’s power unit, and I can see usage data via the in-wall controller or through the official smartphone app. I figured that the app is just a wrapper for authenticated API calls, so the first step was reverse engineering this to get access from my computer.

Claude drove most of this process. I set up a temporary man-in-the-middle proxy to see all data coming and going from my phone. From this I quickly found the authentication parameters, and the API calls used to get data from the power unit. The fields had non-descriptive binary names, but comparing the numbers to screenshots taken within the app made it easy to map what each field represented.

Now I had access to monthly/daily/hourly data for things like:

How much electricity I used
How much electricity my solar panels generated
How much electricity I bought from the grid
How much left over electricity was exported
How much gas I used/bought

I could now make web dashboards that show this information, but I already had those from the app. The more interesting application is then using this information to answer various questions:

Question 1: Why was my electricity bill so expensive last month?

Answer: Consumption was about the same as the previous year. Solar generation was what had dropped.

This question itself was fairly straightforward, but the exciting thing is that now I have a corpus of personal data and a method for answering any small questions like this that may come up in the future.

As a follow up, I found the Open-Meteo historical archive, a database that can show how much sunshine a given location received on any day. This confirmed that more days were rainy/cloudy than last year. And now I have another useful set of data.

Question 2: Are my solar panels still as effective as before?

I expect that performance will decline eventually, and I also worried that if one of the panels was knocked out for some reason it may take me a long time to notice.

Cloudy days create a lot of variance, so I looked at generation/sunlight ratios for only sunny days over the year. Comparing the data across multiple years showed that the solar panels are healthy, running about as effectively as we could expect.

The solar cells have a total capacity of 6.74 kWp, and actual performance caps out at around 80%. That is about what can be expected, especially since they are split across two roof faces.

Question 3: Is keeping ENE-FARM generation off a smart move?

Short answer: yes.

The main issue is that solar provides more electricity than I need during the day, so most electricity generated by burning gas is wasted.

Follow up: What if I just turned it on at night, when there is no sunlight?

Since the fuel cell needs to run hot, there is a significant cost when turning on from a cold start. Also checking the manual told me that the manufacturer recommends at most 10 startups per year, and significantly more than this could void any warranty.

Follow up: What if I just turned it on during winter months?

This scenario was the interesting one. With less sunlight, there are more hours during the day when I am just buying electricity from the grid. There is a ratio of electricity price to gas price that acts as a threshold for when burning gas would cost less, and it becomes more forgiving when there is less sunlight.

I got the recent per kWh and per m^3 prices, and saw that it was very close. Some months were above and some months were below, with it generally within the variance of those two rates. But even in the winter months, the total savings would only come out to be around 1,500JPY per year, and after considering other factors like wear on the fuel cell, keeping it off is probably the right move.

Question 4: Should I buy a residential battery to offset nighttime costs?

Short answer: Batteries are too expensive.

Getting even a 5kWh battery would cover a lot of nighttime usage. I could expect to save 50,000~60,000JPY per year, which is actually a large fraction of my total annual cost.

But installing a 5kWh battery costs upwards of 1 million JPY! It would take 20 years to break even, and the battery wouldn’t even last that long.

Battery cell prices have been dropping globally, but this cost in Japan has stayed mostly flat. Most of the cost comes from equipment and installation fees, so cheaper battery cells has minimal impact. Even with the possibility of receiving government subsidies, this seems unlikely to be practical any time soon.

(The impression I get is that most people who have residential batteries are doing it for disaster-preparedness, rather than financial reasons)

Conclusions

I could confirm that I was doing things mostly correctly, and now I have the numbers and math to back it up. And since I have raw numbers easily accessible, I should be able to answer similar questions in the future as they come up.

Of course, I could have done the same analysis by myself with a spreadsheet, but the reality is that I hadn’t. The AI drastically reduced the friction of digging into the data, and now I have more peace of mind.

Pets, and hobbies shared with dad friends

2026-08-19T11:54:00+09:00

Pets

A while ago we got a Betta, and we recently adopted a hamster as well. The whole family loves them.

Mahjong

I’ve started learning Mahjong, hoping eventually to be able to play with my dad friends. I’m playing mainly on Mahjong Soul and I’m slowly climbing the ladder.

Swimming

Our pool was closed for summer holiday, so I had a little gap in my practice. I’ve started using a pull buoy to work on my balance and rotation. The first times I tried it I was wobbling a lot, which shows how much I needed the practice. I’m doing my best to go through the motions slowly, keeping my core straight with a smooth rotation.

A dad friend who uses the same pool was also there, and he told me that my arm was dropping a lot when breathing. I hadn’t even noticed, so was very glad for the feedback. He also recommended doing side-kick drills with a kick-board, pressing down on the kick-board with my forward hand. This didn’t make sense to me at first — if I’m supposed to work to keep my hand up, what’s the sense in a drill where I’m pressing down? But he told me that it’s a good way to get a sense for feeling the tension of water underneath your hand, and letting it hold your hand up. So I took his word for it and gave it a go, press the kick-board while kicking, no big deal.

And then when I tried my normal stroke again, it was amazing how much more aware I was of my forward hand! I felt it sitting in the water, recognized the tension of the water underneath it, and focused on that sensation to hold my hand up. It was wonderful how he quickly pointed out one thing, suggested a drill to fix it, and that mostly solved it.

Learning Mahjong with AI help

2026-08-19T11:00:00+09:00

A number of my dad friends play Mahjong, so I figured this would be a good time to finally take the time to learn to play. I’ve been able to use AI tools in a way that makes learning extremely efficient (at least I think so).

First, I opened a session with Claude and asked it to talk me through the rules and basic strategy. If I didn’t understand a concept well enough, I would ask it to clarify. When it came to strategy, it offered to prepare a set of drills for me to work through. Given this hand, which tile do you cut? With this opening hand, what will your overall strategy be? If I gave a wrong answer it would point out the mistake, and I sometimes pushed back with my reasoning and we would discuss the tradeoffs.

I imagine that having a private tutor is a huge help when learning anything new, and at the early stages Claude is a pretty good stand-in for a human.

Once I was comfortable with the basics, I started playing against real people online. The next tool I used was this Mahjong AI Utilities site. Some online Mahjong services let you export logs of games, and this will analyze those logs to tell you how well you played. For each move, it creates a statistical distribution of the best tile to drop, so it’s better to deviate from that as little as possible.

Sometimes I could see my error, but other times I didn’t understand why my move was bad. This is when I go back to Claude with a JSON copy of the analysis, and ask it why a particular move was better than mine. It will do its best to explain, I may or may not push back, and I usually come out with a stronger understanding of the strategy. If I have a recurring type of mistake, I can go through drills again.

I’ve found this process to be so useful in improving my play. Without this kind of guidance, it’s nearly impossible to know what I’m doing well and what I’m failing at. It’s perfectly possible to win by luck, but that means you are keeping bad habits without realizing it. I’m hopeful that this focused learning approach will help me to improve quickly.

An email address for humans

2026-08-06T00:00:00Z

My primary email address is hosted on Gmail, and I have used it for basically everything since Gmail was first launched in 2004. I access my email via IMAP and Gmail’s spam filter is great, so I haven’t ever had issues with the service. At the same time I do also want a more curated space for email that I control, which is what led to me setting up a new email account, exclusively for communication with people.

My Gmail address will continue to be used for communicating with machines. Any time I sign up for something, I’ll use the Gmail account. I also feel comfortable publishing this address on my personal website for people to reach out, since the account itself is already all over the internet.

My new account is shared with friends and family, and I also use it when I reach out to new people. If I see a blog post I like, I do my best to send a message to show my appreciation. This way, my people account’s inbox consists entirely of pleasant communication. It’s a happy space isolated from machines.

Physical writing envy

2026-07-24T00:00:00Z

I sure wish I could commit to writing with pen and paper. There are very compelling arguments for why one should write by hand. It’s good for your brain! Science proves it! I’ve been in meetings with people who enter the room with a pen and notebook. They seem so much more attentive and engaged than the people typing something in their laptops.

I’ve tried. I wrote in a journal for an entire year, and then a few weeks into the second, before I let the habit fade away.

At the root of it, I feel that if I put that much effort into writing something down, I want the result to be accessible. Mostly, that means searchable. I want to be able to do something with it later.

If I write something down in a notebook, I’m probably not going to look at it again. And if I am going to look at it again, like that nice recipe for lemon pasta I found, I want it somewhere that’s easy to find – not buried in the middle of a notebook from 2024, or was it 2023?

For some people there’s an immediate therapeutic value in getting thoughts into writing, and there I think the act of writing itself is tangible. I don’t feel this, though, so writing for the sake of writing feel too much like busywork.

Escaping a swimming plateau

2026-07-15T00:00:00Z

I’ve been swimming weekly for almost 2 months now, because I was (am) a poor swimmer and want to improve. The main things that were holding me back are common issues – it was hard to keep my legs up, and I couldn’t breathe comfortably.

In addition to reading and watching YouTube videos, I reached out to a college friend who was able to give me great tips. I feel like I finally figured out the right way to do things, and hopefully I can start building muscle memory to make it more natural.

Horizontal body

For keeping my body horizontal and my legs up, I was already trying to keep my head and chest down in the water, and it was working all right. The missing piece was how I held my lower body. I had to focus more on making my legs long behind me. It seems like longer legs would increase downward force as my feet get farther from the fulcrum at my chest, but I was wrong. Maybe it’s decreased drag that’s working for me? Not sure.

Also, regarding proper tension in my core. For me it was less flexing my abs, and more holding my hips as though I was pressing my lower back against a wall. That plus tightening my glutes helped to keep my legs long and straight.

Breathing position

I knew all the things I had to do to breathe well, and I think it was my low legs that were holding me back. Once my legs stayed high, it was much easier to reach air with my mouth. One surprising thing was that it’s easier to reach air with a low head and high chin (basically upside down) than by lifting your entire head. But it makes sense, since your mouth is on the bottom of your face. Putting your head upside down makes your mouth higher. So keep your ear and the top of your head in the water, and reach up with your mouth through the chin. After a few times, I could feel what it was like to reach up with my mouth while keeping my head down.

Breathing technique

And the breathing itself! This was driving me crazy because apparently I’m very conscious of my breathing patterns and I couldn’t find many people addressing my questions. The situation was that I was doing my best to breathe “well”, whatever that means, but I was getting exhausted. The literature says that 9 times out of 10 that means you’re not exhaling enough and the CO2 is triggering alarms, so I kept diligently blowing out air and it didn’t seem to help. I couldn’t tell if I was breathing in too much, breathing out not enough, breathing out too much, or what.

Bobbing exercises solved it for me. I had initially written them off because I am able to exhale underwater without issue, but what they taught me is that I don’t need to exchange much air to keep my body going. My breathing until then was cycling too much air, and I was essentially hyperventilating through each stroke.

I realized something obvious – that the amount I exhale and the amount I inhale needs to be the same. Otherwise, I’d either run out of air or explode. So then the only two variables I have to work with are,

How much air I exhale/inhale each time
How often I exhale/inhale

Everybody probably has a their own balance that feels best. I tried breathing every two strokes, which means that each breath doesn’t need to exchange a lot of air. In fact, it must not exchange too much air. And once I figured that out, it worked! I eventually want to move towards taking bigger breaths more infrequently, but for now I’m happy that I was finally started to swim more comfortably.

Finished Triangle Strategy

Got it a few years ago and did not finish, but I recently picked it up again and went through two play-throughs to see all the endings. The golden ending would have been annoying to grind everybody’s level up, so I just put the difficulty to Very Easy and breezed through. I know this would have been extremely satisfying to clear on a high difficulty, but it’s not what I was in the mood for.

Overall I was impressed by the game, and especially with its story. The choices were difficult, the consequences felt real, and the scope was huge. The endings were excellent, too. Each ending corresponds to one goal (value, even) you choose to prioritize over others, and the conclusion shows you successfully achieving that goal. But, there is always the undertone of whatever you sacrificed to get there so that you can’t be completely satisfied. The golden ending ties all those loose strings together so that you can have the best of all worlds, and I thought it was very well sculpted.

Building and tinkering

2026-06-15T00:00:00Z

I’m been in a big building and tinkering mood recently, and have been really getting into Valheim. I play solo and honestly don’t have too much time to put into it, but I’ve been building larger bases and am legitimately excited to keep trying new things and progress further. I’m not much good at it, so while I’m looking at online resources for reference I’m trying to keep my expectations from getting too high.

I never was able to get into Minecraft and had resigned myself to that fact that I’m not the type of person who enjoys sandbox games. But something about Valheim is giving me some real joy. Partly the game aesthetic, and partly just my state of mind probably.

In another somewhat related point, I’ve been using Claude Code to create lots of little tools for myself and fun game prototypes, as well as working on a system that will let it run mostly autonomously so I don’t have to babysit it as it works through larger projects. This might seem like it’s taking away from my opportunities to build myself, but I love the process. It’s like working on a big Rube Goldberg machine, and the joy when I’m given a finished product that largely works as expected is real.

None of these things have any real significance, and I have to real about that. It’s tinkering, and I don’t mean that in a diminishing way. It’s a perfectly legitimate hobby, I think, and there are cases where it help me to learn new things and grow.

(This is a very unpolished post, but I want to get in the habit of publishing more, so this is what we get.)

New hobby and new friends

2026-06-01T00:00:00Z

Swimming

As I promised myself, I started swimming this month. I still need to put in a lot of work, but I’m hopeful that I can make some reasonably improvements — both to my swimming form, and to my fitness in general. I’ve started compiling my notes from each session here.

The neighborhood

It’s been 6 years since we moved into our neighborhood, and I’m so grateful at how great of an environment it is for our kids. We live in a block of around 15 houses arranged in a little cul-de-sac with a park, and there are around 30 kids between the ages of 2 and 8.

Recently the parents have been getting close, too. We had a get-together with all of the dads going out for dinner and drinks, and the moms and kids had a big block party with pizza and treats at home.

Games

I picked two older games that were on my shelf – Triangle Strategy for Switch, and Valheim for PC.

Triangle Strategy was a recommendation from a close friend a few years ago. I enjoyed it, but I’m not sure if I finished an entire playthrough. I want to enjoy strategy games more than I actually do, but sometimes I get urges to pick one up. Right now I’m almost done with my first playthrough, and I hope to get through NG+ too to see another ending. I just have to keep up the momentum.

But at the same time I’m playing around with Valheim, having a pretty great time with it. I first got this maybe when it was in early access, and I think the early grind made me lose interest pretty quickly. I do remember making a fairly nice lake-house though. I’ve just expanded into the second biome, and the grind is still a bit tedious but I’m pacing myself and having fun.

Task Paralysis & AI

2026-05-13T00:00:00Z

This post by Daniel Gilbert immediately resonated with me, because I struggle with procrastination and have found AI tools to be surprisingly helpful in overcoming it.

I have a stale task waiting to be done, but I just can’t bring myself to get started working on it. All I really have to do is pull up my AI agent and say “Hey I gotta do this thing”.

The peppy AI will immediately respond with Hey sounds good, want me to do XXX for you? or What do you think about YYY, should we work through that together?

And I’ll either say Yeah that’s what I was thinking or No, I want to do this instead or Actually I’m not too sure, what about…

And it almost doesn’t matter at all what the AI actually says. What it has given me is momentum. Because now my head is in the game, my fingers are working, and I’ve already taken the first step without even realizing it.

Just like that, it’s now so much easier for me to keep working and make real progress. Getting started is the hardest part, but the AI will just charge through, trepidation be damned. Repeat this over the course of the day whenever I want to switch over to a new thing, and I actually have a good shot at leading a productive day.

Generative AI lets you consume Creation

2026-03-02T13:45:00+09:00

Consumption versus Creation.

I’ve long been conscious of two contrasting categories of pastimes – those that consume, and those that create.

Consumption is fast. Consumption is passive.
Consumption is easy.

Consumption in today’s world is limitless, as there are an infinite number of sources that each provide an infinite amount of content. It’s easy to blow this into a dystopian image of people who never leave their couch, but in many cases consumption as a hobby is harmless. People learn about the world, are exposed to new ideas, feel delight or shock or compassion or curiosity or anything, really, at whatever they encounter. And that’s fine.

But consumption is, I think, fulfilling only on a superficial level.

Creation is slow. Creation is active.
Creation is hard.

There are far fewer creators than consumers, because it is demanding of time and effort. Creation is technically limited by your ability, although in reality there is so much that you can accomplish with only the slightest amount of skill if you allow yourself the challenge.

Creation can be fulfilling on a truly deep level, proportional to the amount of time and effort you pour into it. I think this can be felt by others, too, because there is a feeling of awe that is evoked when interacting with a work that is full of care.

I’ve always taken pride in being a creator, in my own humble way. I’ve tried to be conscious of the amount of time I spend consuming versus creating, because it is easy to slip into habits of excessive consumption. I’ve learned that I tend to be happiest when I am able to devote time to creative pastimes.

Generative AI changes things

Of the many things that generative AI is changing about our world, one is allowing people to consume the process of creation.

Type some words, hit a button, and something novel and interesting comes out. This is consumption. It generates an infinite number of things that can be consumed, each one tailored specifically for you and what you desire. It take minimal effort, and you can interact with it to your heart’s content. This is a consumer’s dream.

The novel twist is that it also feels an awful lot like creation. You imagined something, put in some set amount of effort, and now the thing exists. Because you willed it to be so. You can show it to people, and explain that it is yours.

It strips away the slow, active, hard parts of creation, and serves it to you in a fast, passive, and easy way. You are consuming the experience of creation.

How do I feel about all this?

I’m really not sure.

I’m not writing this from a high moral position. I use generative AI at work and in my daily life, and these insights came from recognizing the dynamic at play within myself.

I feel like I should feel appalled. That the experience of creation is cheapened and commodified. That I am selling my (limited) skills as a creator short, and jumping into an exo-suit that will only serve to atrophy my muscles. That too many people will start to assume that creation is, or should be, fast and easy, leading to a sharp decline in craftsmanship and overall quality of a technological life.

But I have to admit that it is so much fun. I can generate useful tools that provide real value to me and my family. These productions can feel great to use, and my pride of them does feel justified, because it is a good solution to a problem that I recognized, and I did put attention to the details that matter to me.

I feel empowered as a creator like I haven’t been since I was learning HTML/CSS for my GeoCities site. Small chops for a small world. The world is so much bigger now, and these big AI chops are so satisfying.