In fact, there are some 36" and larger induction ranges --- you can custom
order from the likes of French makers such as Lacanche. Obviously, $$$$$$.

Beyond that, the problem is limited demand. Diva de Provence made 36" induction ranges for what, 5 years? They went bust.

Consider how little demand there is for any electric range that is 36" or larger. I mean, Frigidaire has discontinued the 40" models which it used to make (and which also were sold as Kenmores). Brown Stove Works still makes a four-coil-burner 36" electric ranges which, I believe, are sold under the Summit brandname. Verona has (or had) a 36" five-burner radiant electric range ($$$). Heartland has an antique-look 48" radiant burner stove ($$$$ for the looking like an antique wood-burning cookstove). That's it.

Seems to me that power supply requirements really do not affect this market segment
very much. Those would be pretty much the same as you would need
for for setting up a 36" induction cooktop over top of a 30" electric
oven. Folks who want larger induction cooktop surfaces go that route which, I suspect, pretty much eliminates the market for larger induction ranges. Also, there really isn't much demand for residential 36" electric ovens, either.

Yes, it's the power needs thing, primarily, and only the low demand a distant secondary factor. There's enough demand out there for a decent niche production run. A 36'' induction over a 30'' oven needs a power circuit for each appliance, not a shared single circuit. Until a company figures out how to safely utilize a similar double breaker supply for a single unit (not that hard to do) you're gonna have to do the separate components thing too.

You could try a combination of oven and separate induction cooktop. In the cooktop category there are numerous 36-inch induction range models. The Electrolux/Kenmore/Frigidaire lines have them; the Bosch/Thermador lines have them; Wolf has them, etc. Search here on this subject, e.g., the topic:

http://ths.gardenweb.com/discussions/2246536/36-induction-cooktop-with-bridge?n=86

or view The Induction Site website.

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