Founded in 1989 in St. Helena, Calif., Vineyard 29 winery in the Napa Valley wine-growing region, was purchased by Chuck and Anne McMinn in 2000. Since then, the couple has been committed to sustainable practices that reduce emissions from their winery as well as toxins into the environment. Today, the winery processes 100 acres of grapes to produce about 10,000 cases of wine per year.
As part of their commitment to the environment, the McMinns installed two 60-kW Capstone microturbines to provide necessary services to the winery. With up to 120 kW of electricity produced by the systems, the combined cooling, heating and power (CCHP) microturbines run on natural gas.
To process each gallon of wine, 3 gal of hot water are required. The system co-generates heat that is captured to produce hot water. The water also is used to run the cooling system through an adsorption chiller. The chiller is needed to control the fermentation process and to run the air-conditioning system during the summer time. In the wintertime, the hot water is also used to heat the building.
Among the innovations deployed at the CCHP system at Vineyard 29 is a 20-ton adsorption chiller utilizing the Nishiyodo technology. Like conventional absorption chillers, adsorption chillers use recovered heat instead of electricity to produce cooled water. However, they do not require the use of lithium bromide (LiBr), an ozone-depleting coolant. Instead the cooling is achieved by using water as a refrigerant that is adsorbed onto a silica gel media. Then, under a low pressure of 7 kPa, heat is removed from the system by boiling off the water, yielding a stream of 30 percent propylene glycol/water mixture at 40°F (4°C) for cooling the wine tanks, the cave and the building. Toxic chemicals are avoided with this chiller and little maintenance is needed. Overall, adsorption systems have a coefficient of performance (COP) of up to 75 percent.
In addition, a Dolphin pulsed-power system from Clearwater Systems Corp., Essex, Conn., is used in the cooling tower from Evapco, Westminster, Md. This treatment system disinfects water with pulsed-power discharges. The process ionizes and purifies the water, prevents the buildup of scale, and does not require the use of germicides.
According to Chuck McMinn, Vineyard 29 obtains all of its electricity from the CCHP system at half the cost it would take to power and heat their winery using conventional electricity and natural gas.
“We produce 100 percent of the electricity that we use here at Vineyard 29. We do that at about half the cost of buying electricity and the natural gas we would need to run our boiler. At the same time, we are seven times less polluting than a PG&E power plant,” says Chuck McMinn, owner of Vineyard 29.