“We’re sitting on top of the world,” said Tim Mondavi, talking about the new winery that he and his sister, Marcia, have built on Pritchard Hill, overlooking Napa Valley.

The new winery is one of the most advanced in Napa Valley, culminating Mondavi’s 40 years of harvests. It contains many features that hearken back to the past, though it incorporates many of the best ideas of modern winemaking.

Perhaps most impressively, it includes many of the ideas developed at UC Davis by Roger Bolton for sustainable winemaking.

Let’s start with the basics. The attractive building designed by veteran winery architect Howard Backen nestles into a hill that provides one wall and a site for a future cave for aging wines. It is finished in earth tones with olive and manzanita trees framing the entrance.

The winery isn’t large, being built to optimize the grapes harvested on site. “The winery is all about the vineyard,” said Mondavi.

It includes tanks sized for each of the 37 blocks of vines from the planted 62 acres on the property, where the vineyards have southern and western exposure. The vines are 55 percent cabernet sauvignon, 25 percent cabernet franc (a high percentage historically for Napa Valley reflecting the historical plantings in Bordeaux), 15 percent petit verdot and only 5 percent merlot. They harvested 1.85 tons per acre last year.

Not all of the vines are producing yet, however, and for now the winery is using quarter-ton bins for some of the blocks.

The number of tanks allows winemaker Kurt Niznik and assistant winemaker Carrie Findleton to optimize each lot, and the best of the lots are eventually blended to create the signature wine, Continuum — though they do produce a second label, Novicium.

After careful field selection that removes unwanted grapes, the optimum berries are sorted before and after destemming. After light crushing to crack the berries, they flow by gravity into tanks for fermentation.

All of the fermentation tanks are oak (75 percent) or concrete (25 percent) in the shape of truncated cones. The only stainless steel tanks are used for rack and return processing to get the wine off seeds and other unwanted deposits, and for blending.

The fermentation tanks include cooling coils; those in the concrete tanks are embedded in the walls.

Mondavi has fermented in barrels in the past, but this year the tannins were strong enough that he felt that was unneeded. From pre- to post-soaking, including fermentation, the wine has a total maceration time of up to 35 days.

During this time, the wines are pumped over daily with using one pump per tank and permanent piping, and the wine below the cap is stirred with permanent paddles.

After completing fermentation and maceration, the new wine is drained from the oak tanks into 100 percent new small French oak barrels for malolactic fermentation.

The pomace is pressed and barreled separately, but the lees are kept with the wine in barrel for an extended period of stirring to enrich the body and texture of the wine.

The wine is clarified slowly and naturally through traditional settling and racking techniques. In total, Continuum wine spends 20 months in barrel.

A sustainable winery

The winery features many advanced features for sustainability: The walls are thick and filled with foam insulation.

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Skylights brighten the place but eliminate direct sunlight. An arbor will shade the south-facing wall. The winery is unusually uncluttered, with needed plumbing and machinery hiding in tunnels behind the tanks, and plumbing in place eliminates the need to run hoses all over.

The air handlers are hidden, too, and all machinery is on flexible casters to minimize sound and vibration, a bugaboo of Mondavi’s.

A solar water system heats water for washing, and the winery collects rainwater, stores it and purifies it for winery use and firefighting, though excess water can be piped to irrigation ponds.

Heating and cooling equipment is sized to allow slow changes for minimum energy use and shock to the wines.

Pumps are driven by air, which is discharged outside to reduce noise.

And since the tanks are covered, all carbon dioxide is collected and discharged outside, too, both for safety and to reduce humidity and heat in the winery.

Mondavi plans someday to sequester the carbon dioxide, perhaps by bubbling though a calcium hydroxide solution to precipitate calcium carbonate, which has many uses.

Mondavi admits that the winery won’t be finished for years, and a number of its aspects remain to be incorporated, notably the planned aging cave, photovoltaic arrays for electricity, more tanks and the carbon sequestration.

For now, however, the winery is already among the most advanced in the industry.