This article is full of errors, from the details up to the overall idea.

TEGs are not "more sustainable" than PV panels. As the article points out, they're made from similar materials, using the same fabrication technologies, except that PV panels include some plastic; and TEGs typically use exotic, scarce semiconductors based on heavy metals, like bismuth telluride or lead telluride, rather than abundant, cheap semiconductors like silicon. (Silicon is too good at conducting heat to make a good TEG.) I guess Kris De Decker just really doesn't like plastic! But a much bigger issue is that PV panels usually last decades, except for the small minority that get smashed, while TEGs tend to get burned up because you have to put them in a fire to make them work, and even aside from the danger of accidental overheating (because your water tank emptied out, say, or the air currents in your wood stove were different from usual) the Arrhenius equation governs a wide variety of TEG and PV failure mechanisms. So TEGs are not "more reliable".

The article argues that solar panels are not being recycled because they have plastic in them. This is false. The truth is that solar panels are not being recycled because almost all of them still work, even those manufactured decades ago, and manufacturing is growing rapidly, so there is not a sufficiently large pool of broken solar panels to supply any significant fraction of the demand for silicon.

TEGs are not "less costly" than solar panels. Solar panels are https://www.solarserver.de/pv-modulpreise/ €0.17 per watt now. https://www.dx.com/p/yb3981-diy-150-c-thermoelectric-power-g... is a TEG rated for 150° which can theoretically produce about 3 watts for US$9: 15 times as expensive. Typical PV capacity factors are around 20%†, so even if the TEG got a 100% capacity factor — which it won't, since you don't have a constant 3-watt load to hang off it — it would be three times more costly. (Is there a cheaper source for TEGs somewhere?) This also tends to show that more energy and materials are needed to manufacture TEGs than equivalent solar panels, since that's what most of your money goes to buy.

(150° is about the limit for bismuth-telluride TEGs — bismuth alloys and intermetallics tend to melt at low temperatures. It is not true that, as the article says, that "the hot side of bismuth telluride modules withstands continuous temperatures of 150 to 350 degrees", nor are Bi₂Te₃ modules "the most efficient ones".)

The article argues that TEGs are "100% efficient" because any energy not harvested by the TEG is used to heat your house. Aside from this being undesirable in the summer — a significant concern for many of us here in the "global south" that Kris De Decker pretends to care about, from his apartment in Spain — it's also the case that burning up kilowatts of precious energy directly into low-grade heat is an extremely inefficient way to heat your house. The apartment I'm in here is primarily heated by an air conditioner with the capability of functioning backwards, in which mode it produces about 3 kilowatts of heating in exchange for a single kilowatt of electricity, for 300% "efficiency". (This is not a violation of thermodynamics; the Carnot cycle is reversible, and the indoor and outdoor temperatures just aren't that far apart.) Producing the same amount of heating with the oven or a wood stove would waste two kilowatts of gas or wood.

Additionally, wood stoves are seriously fucking bad for your health. They produce massive amounts of carcinogenic smoke.

TEGs do have real merits — I've loved them since I was a kid. They can provide small amounts of power, at very low efficiency, in a totally autonomous, independent, and portable way. You might be able to charge your phone, run a reading light, or trickle-charge a battery. But they are not an alternative power source for your house. They are not going to run your vacuum cleaner or your e-scooter, contrary to the misleading illustrations in this article. A normal household vacuum cleaner needs 500–2000 watts, and at 5% efficiency that would mean running 10 to 40 kilowatts of heat through your TEG, a power level at which you will quickly cease to appreciate the space heating effect. However, as John Nagle pointed out in https://news.ycombinator.com/item?id=23356206, the end-to-end efficiency in the Lebanese study cited was not 5% but 0.04%, because most of the energy in the fuel goes right out the chimney, and most of the rest goes directly into the house, not through the TEG.

So what could have motivated such a mendacious article? Did Low Tech Magazine get an advertorial contract, similar to The Atlantic's famous David Miscavige Leads Scientology to Another Banner Year deal? Does Kris De Decker simply have no interest in whether what he's writing is true or false, scraping together whatever argument he thinks he can trick people into believing in order to support his preconceived conclusion? Either way, this article destroys the credibility of Low Tech Magazine. (Unless it's a false-flag operation? Maybe someone is impersonating Kris De Decker to discredit him?)

† In polar countries like Germany, the Netherlands, or England, PV capacity factors may worsen to 10%. Near the Arctic or Antarctic Circle things are even worse, and within them of course you can't use solar power without a seasonal energy store, which is totally impractical for most uses.