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07:26 Monday, 1 June 2026
Current Wx: Temp: 52.02°F Pressure: 1017hPa Humidity: 78% Wind: 3.47mph
Words: 976

Because it's hard to think of titles for everything.

Here is a reasonable corrective to the AI hysteria that seems to be swelling. Siting data centers, and powering them, is challenge. But it's not one that's exclusive to AI.

We finished watching For All Mankind the other night. It feels like they really leaned into The Expanse. That's ok, I guess. I'm mostly watching it out of inertia these days. There isn't a single character I'm really invested in, and that feels like it's by design since each season leaps forward by about a decade. And the sets still look far too antiseptic. But whatever. I thought the season finale was pretty good. While the sets may be antiseptic, incinerating a bunch of people wasn't. Overall, I'd say this season was better than the last one.

Then I watched the premiere episode of Star City and immediately decided it wasn't for me. Too depressing in the KGB storyline. I think the sets are far less antiseptic though!

I'm going to spend time with Chapter 2 of John Siegenthaler's Modern Hydronic Heating & Cooling. It's the one that covers calculating heat loss. Maybe I'll play with one of my programmable calculators and party like it's 1984.

Housing construction is one of those things we take for granted. It's not the kind of thing that gets covered in the popular press. Although it's likely the most expensive purchase any of us make in our lives, most of what gets written about in "popular" media covers fashion trends, not the nuts and bolts of how a house functions as a shelter system.

That seems like an enormous gap in our basic knowledge, and I don't know how we might go about filling it. Maybe secondary school curricula need to include system dynamics with housing as a case study of some kind.

All that is to say that, the more I learn about it, the more convinced I am that we have gone about heating, cooling and ventilation (and domestic hot water) all wrong, because energy was "cheap." In the case of fossil fuels, natural gas for example, we're burning a fuel at over 3,000°F to raise the air temperature in a home 30 or 40 degrees!

Because fire!

And we use that energy to heat or cool air, and then blow that air around the house through large, leaky ducts that gather dust as it transports air and dust around the house. It's inefficient because air has a very low heat capacity compared to water.

But most of this is "out of sight, out of mind," until it stops working. Maybe we're aware of tax incentives for upgrading devices to be more efficient, but we just sort of take blowing air everywhere as the best way to heat and cool a house.

I associated radiators with antiquated technology. How would we ever have Bruce Willis crawling through the Nakatomi Building if they used hydronic heating and cooling?! (You still need to move air for ventilation, but the quantities and velocities are smaller and likely too small to crawl through.)

Heat pumps still get a bad rap from a lot of people, you see it in the YouTube comments. If people are experiencing poor performance from a heat pump, it's because the system wasn't designed properly. Either it's too large or too small. If you have a leaky old house, then you probably lose most of your heat just through convection, air movement from the outdoor environment to the indoor. Many of those old leaky houses have oil or natural gas boilers that heat water to send to radiators. ("Emitters is the preferred nomenclature, Dude.") Modern cold weather heat pumps can produce water at 158°F. The question then becomes are your emitters properly sized and located? Perhaps not for using a heat pump. So it may not be a simple matter of retrofitting a heat pump in lieu of a gas boiler.

And sizing is critical. Too small and you can't move enough heat fast enough to overcome the heat losses. Too large and you risk short-cycling the compressor on the heat pump and shortening its working life by years. To say nothing of paying for capacity you simply don't need.

So it's a more intellectually demanding exercise to design and install a hydronic system; but it's simply not the case that "heat pumps don't work." They do, but they're not a one-for-one swap with a boiler. Sometimes they can be, but probably not in very old homes. You may need a buffer tank, which takes up space not formerly needed, to prevent short-cycling.

Anyway, the point is that understanding how to maintain the indoor environment of a home, including its air quality, demands a far more thoughtful approach than what we have heretofore been able to get away with. It's unfamiliar to customers and it's often just as unfamiliar to the trades who do this kind of work. Not a recipe for success.

I'm grateful that we have the opportunity to kind of do this "right." We hope, anyway. In addition to the unfamiliarity with air-to-water heat pumps, the thermal performance of ICF construction adds some uncertainty to the size determination. The effect of thermal mass on heat flow is not well characterized. Our ICF R-30 walls get their R-30 rating just from the EPS foam. It will likely perform like an R-45 to R-50 wall in practice, due to the thermal mass of the concrete retarding the movement of heat from the interior to the exterior of the house.

I'll run the numbers with three R-values and see how they affect the overall heat loss, which is one of the factors to determine the size the heat pump we'll need.

Anyway, time to crunch some numbers.

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