That temperature (obviously) varies in the temperate zones, but typically deep-soil/constant earth temperature is, for example 57F in New England(6 feet or more down). I suspect that in the wine regions of France, deep cellar temps would be in that rough Range as well.
I used this reality to build a succession of 4 basement wine-cellars, of increasing capacity and insulation capacity, across 4 homes. My previous home it was a double 2x6 walled fiberglass insulation with 12” air gap between walls, dual doors, and dual insulated ceiling. So, around R90 in the ceiling, and R72 or so in the walls. Open To the basement concrete floor at bottom. It ran a stable yearly cycle of between 56-58, trailing the seasons by about 3-4 months (so warmest it got was in around October or November, and coldest in April or May. That was an epic effort, but held 2000 bottles, plus other stuffs.
We moved to Texas in 2018, and I moved about 750 bottles along. We then bought a used huge furniture grade indoors wine cabinet. It didn’t hold all 750, so the “less good” ones ended up in boxes in the corner. By the time we moved back to New England, we had drunk it down a bit. But would need a wine cellar in our new home here. I took opportunity to sell 6 cases of the “best of the best” as it had appreciated in value to where I was like ‘I need the money more than any wine’. Got almost 5 digits worth. (Most were 1982, 88, 89 and 90 Bordeaux, including first and second growths).
Fortunately we have a basement! So I just build a small room, against floor and outside basement NE - facing (but shaded) wall, and LIGHTLY insulated it with foam board. I took the AC unit from the furniture piece (which we could not move as it was too large to fit into anyway into the basement in this home, and too tall to work in any room inside (texas typically has 8+ foot ceilings, New England 7 1/2 or slightly less) and mounted it.
It’s holding steady 57F with no usage of the Unit so far (of course we are still in winter).
So yes, cellar temperature, REAL cellar temp, is perfect for storing and aging quality wines. If you own them LONG enough, you can make obscene profits after 30+ years for the right wines. We do it for the wine and gourmet meals, because if you buy wine this way (futures, discounts for case lots, etc.) and store them, you can enjoy wonderful 10-25 year old aged reds for a relative bargain. (E.g. I paid no more than $50 for any of the bottles I later sold for so very much more).
Now, almost retired, we’re drinking things down; nonet cost to buy over-priced plonk today, nor pay ridiculous prices of $75 or more for what I consider mid-grade California (or other region) wines. Hell, I only paid $200 in a restaurant in NYC when I proposed to my wife (Tavern on the Green if anyone remembers the place) for the bottle of 1961 Latour we had.
It’s fun to open a bottle I paid $25 for and drink it, knowing it is of the quality of $200 wines of today.
So add “worry about losing taste/smell as age” to the audiophile nervosa “worry about losing hearing as age” LOL
(Wine’s an alcoholic beverage just like Whiskey, Bourbon, Scotch after all…)
WINE ON THE SINE!
