While celebrating its history, Rhine House at Beringer Vineyards, north of St. Helena, has also joined the green/sustainable revolution.

For the past year, one of Napa Valley’s most iconic landmarks has been undergoing a restoration from the ground up — literally.

Rhine House has been brought into the 21st century with a geothermal heating and cooling system, seismic upgrades, restoration of the original stained glass windows — and experts uncovered the original hand-painted stencil molding on the walls that has been covered by decades of paint and wallpaper.

Last Saturday, the first floor of the Rhine House was opened to the public on a limited basis. By December all projects, including restoration of the second-floor private tasting rooms, should be completed.

A series of events will be held around the holidays to celebrate completion of work at the Rhine House.

Going geo

Invisible to the public eye, buried in the front yard of Rhine House, are 28 holes measuring about six inches in diameter that go down 250 feet, tapping a geothermal zone that maintains a constant 55 to 65 degrees. The result is the building uses free energy from the earth.

It’s all about reducing “ones carbon footprint,” according to Elizabeth Hooker, public relations manager at Beringer Vineyards. Rhine House will be reducing its greenhouse gases and other emissions associated with heating and cooling the building.

She said more than $5 million is being spent to install the geothermal system and to restore the Victorian/Gothic structure that is the winery’s tasting room and visitor’s center.

Installation ofl a geothermal system depends on the size of the building and amount of property available for drilling holes down into the earth.

Rhine House is about 6,000 square feet with 17 rooms. The geothermal system at Beringer occupies about 200 square yards in front of the mansion.

From the geothermal field in the front yard, the system at Beringer goes to a pump that provides cool or warm air to the stately Rhine House.

It will be at least 10 years before the winery makes up its investment from an energy-savings perspective, according to Hooker. “But we believe that its value lies in its minimization of our impact on the community with our heating and cooling needs,” Hooker said.

The old heating and cooling system on the back of the mansion was beyond repair — it was obvious a new system was needed, Hooker added.

According to the Environmental Protection Agency, geothermal is the most energy-efficient, environmentally clean and cost-effective system.

Layers of history

While installing the geothermal system, restoration was undertaken on the front entrance to the Rhine House. It had been closed for many years because there was a fear the stained glass, installed in 1884, could be damaged. So, for many years guests entered the hospitality center through a side entrance.

Frederick Beringer, who built the house for $24,000, spent one-fourth of this total on stained glass window panels, which cap the eight-foot tall windows in rooms with 10-foot-high ceilings. There are 40 panels in the house, with each room having a different theme.

Restoration of the stained glass panels was completed by Nzilani Glass Conservation in Oakland and took about 900 hours.

Beringer made the decision to move forward with the restoration after state legislation was passed that required all freestanding masonry structures to undergo seismic retrofitting.

For the seismic upgrades, holes were drilled in the stone walls of Rhine House and filled with steel rods.

In addition to the Rhine House work, Beringer is installing solar panels at its processing facility across the street. The Upvalley winery has just been certified “green,” according to Hooker. “This isn’t something you can do overnight.”