Black Stallion Winery, a CERTIFIED SUSTAINABLE winery in Napa Valley’s Oak Knoll District with Cabernet Sauvignon as its signature varietal, has been owned by the Indelicato family and part of Delicato Family Vineyards since 2010. These third- and fourth-generation vintners have helped introduce many sustainable practices on the 32-acre estate, focusing especially on reducing energy and water use. Director of Winemaking Ralf Holdenried has overseen many of the efforts on the winery’s path to certification.
You have achieved some energy savings by shifting your time of use. Can you share details?
Unless you have a method of energy storage, you get energy at a winery as you demand it. Our biggest energy need is for cooling our barrel warehouse, and we have switched the energy load to off-peak hours to get better rates. We are overcooling at night, utilizing the cool air from outside, and undercooling during the day.
You worked with the utility companies to bring your energy and water use down. How exactly did they assist you?
We know that electricity and water pumping in the winery and vineyard are some of our biggest users of energy. We have been working with PG&E to figure out where we use the most electricity. Is it lighting? Cooling? Cellar operations? We installed a lot of “smart” meters throughout the winery so that we can analyze this more effectively. We replaced all the incandescent light fixtures in the barrel room—about 75 of them—with LED lights, which use less electricity and generate less heat.
One of our biggest energy needs is cooling the fermentation tanks. It’s hard to quantify the savings but insulating all the glycol lines used for heating and cooling made a big improvement.
In the winery, we installed new tank- and barrel-washing equipment and high-pressure hoses that use less water. In the vineyard, we installed soil-moisture probes to do soil moisture measurements. This information, in addition to what we can see, allows us to fine-tune irrigation and develop an annual water budget. We are working on a plan that includes additional water meters and cloud-based tracking software that will alert the team when a pre-determined water-usage amount is reached.
We also installed a variable-frequency drive on our main irrigation well so the pump isn’t just 100 percent on or off. It runs at the pace you need.
We started collecting data on water use about three years ago. By recycling our process water for irrigation and with the tank- and barrel-washing improvements, we’ve seen at least a 20 percent reduction in water use in the past three years.