Introduction/background

Zucca Mountain Vineyards is a small, family winery located in the California Sierra foothills owned and operated by Gary and Carol Zucca. After researching and discussing various construction methods for a winery, including packed earth, straw bale, steel, wood frame, and others, we decided on using salvaged 40-foot refrigerated cargo containers to build our winery.  The purpose of this article is to present a case study of how refrigerated cargo containers can be used in a small winery and to discuss the advantages and disadvantages of their use.

Cargo containers generally come in two types: Un-insulated, and refrigerated (reefer). Standard size is 40 feet length, 8 feet high, and 8 feet wide. Some are 20 feet in length and some, designed for light cargo (high cube), are 9 feet tall and may be up to 53 feet in length.  Reefer containers have 4 inch insulated walls and are chilled by reefer units capable of chilling the cargo to 20 degrees F. When the reefer refrigeration unit fails, the containers are either cut up, sold for scrap metal and the insulation sent to land fill, or are sold to buyers for other purposes. Reefers can be used to store wine tanks, barrels, and case goods while unrefrigerated containers can be used to store wine equipment, chemicals, and whatever other materials that do not require refrigeration.

Winery layout and costs 

The production and storage area of the winery consists of four 40’ insulated cargo containers surrounding a 33 X 40 foot crush pad. Fermentation is done in ½ ton bins on the crush pad. Figure 1 below shows the layout of the winery. The container on the left is used for barrel storage, the one on the right for five 1,500-liter, variable-capacity tanks,

; the two containers in the rear are used for case goods storage. The container on the right has a shed roof adjoining the outside of the container and holds four 2,000-liter refrigerated, variable capacity tanks. The space is also used for bottling, shown in Figure 1a below.

A standard 40-foot reefer container contains 320 square feet of storage and costs about $9,000, depending on location and transportation costs, or $28.00 per square foot. The four containers used in the winery have a total of 1,280 square feet of refrigerated storage.

Cooling

Containers are cooled with 18,000 BTU window air conditioners that are commercially available at any building supply company for about $300 each. Summer temperatures sometime reach 100+ degrees for a few days, with many days in the mid nineties. The internal temperatures of the containers remain constant at about 65° F unless there has been unusual activity that requires the doors to remain open for long periods. 

Wineries using traditional construction with high ceiling heights and with tanks, case goods, and barrels in one unit require more air conditioning and have more variation in temperature because of the vertical distribution of cool air and the need to expose the winery to the outside temperature every time case goods, barrels or tanks are accessed. Modularizing the various aspects of the winery, case, barrel, and tank storage, allow work in one container without affecting the temperature in other containers. This, along with the eight-foot ceilings in the containers greatly reducing the energy costs. Under normal seasonal conditions, the air conditioners are turned on in late April and turned off in late September, and the wine is left at ambient temperature over the winter. The insulated containers act as insulation during winter months and the wine remains between 55°–65° F. 

Winery operations

Grapes are weighed, sorted, crushed, and fermented in half-ton bins in the crush pad. The outside crush pad has a mist system and awnings that are used to cool the fermenting wine and winery workers. After fermentation wine is pressed into tanks in the tank container or chilled tanks under the shed.

Barrel storage is done on barrel racks stacked two high with a maximum capacity of 48 barrels, but with the necessary topping off equipment, a more reasonable capacity is 40 barrels. If barrels are stacked rather than put on racks, the storage would obviously be greater. However, racks facilitate moving barrels inside the container with a pallet jack inside the container to the outside where the forklift can transport them to the crush pad where they can be worked on. The distance between barrels is about 18 inches, so the person working the barrels needs to be thin and able to sidle between the barrels. The barrel container layout is shown in Figure 2 below.

Wine is bottled under the shed and case goods are stored in the two rear containers. Each of the case goods containers are able to store two rows of nine 42” x 48” pallets with three tiers of 15 cases on each pallet for a total of 45 cases per pallet. Pallets are stacked two high, allowing 90 cases per pallet footprint. Thus, each container can hold two rows of nine pallets stacked two high or 2 X 9 X 90 = 1,620 cases of wine.

One container we call the Storage Container, is filled with the case goods just bottled.  As can be seen in Figure 3 below, some wine is “buried” behind other wines and is inaccessible without removing all the wines in front of it but, since these wines are not yet released, we can store them in two rows. Nonetheless, there are always situations where we shuffle pallets around to open access to wine or consolidate and fill empty spaces. It can appear to be somewhat of a Rubric’s Cube operation, but it works. 

     The second case goods container, we call the Breakout Container, is used for wines that have been released and are removed weekly to replenish the tasting room stock or for wine club shipments. Because it is necessary to have all access to all wines, only one row of pallets can be kept in this container. The wines we sell from the breakout container are replenished from the storage container. As we deplete our inventory we consolidate case goods in one container and use the other for glass when we bottle. The Breakout Container is pictured in Figure 4 below.

Local permitting and electrical issues 

The winery is located on a 20-acre parcel that also has a residence, so a county permit was needed to add another electrical meter and panel, trench electrical cable to the winery area, and pour the crush pad. Electrical panels and outlets were placed at the sides of the crush pad next to the barrel and tank cargo containers. Since there is no wiring inside the cargo containers, and since no county permit is needed to place cargo containers on agricultural land, no other county permits were needed. Not having to go through extensive permitting processes required for a any type of building saved a great deal of time and money and was a large factor in our decision to use cargo containers.

Conclusions

The purpose of this article was to describe the use of Reefer containers in a small winery. Reefers have been used successfully in our winery for the past ten years and over this period of time we have found they have numerous advantages, among which are:

• Scalable. One of the main barriers to entry in the wine business is the cost of winery construction and when constructing a winery with traditional construction methods, the winery must be over-built with the hope that wine sales will grow and the business will be able to expand to the winery. The use of containers allows start-up wineries to begin with only what is needed and then expand as the business grows. We first added a container for glass and case good storage then added barrel storage and finally the crush pad and moved the entire production to the new venue.

• Ecologically sound. Since the used reefer containers will be cut up for scrap metal and the insulation sent to land fill, reusing the containers reduces waste.  

• Economical.  Cargo containers have several economic advantages over conventional winery construction.  The containers are airtight and prevent pests from damaging stored wine or equipment. Being air tight, the containers need to be air-conditioned for only about six months a year, thereby making very efficient use of energy. Containers do not generally require building permits, architectural plans, plot plans, or other expenses associated with conventional construction. Finally, the modular design permits accessing one container without interfering with the cooling capacity of the other containers.

Cargo containers also have obvious disadvantages. They have an industrial look and feel and lack the architectural style that might better appeal to retail customers. This is not an issue with our winery because we have a tasting room in a nearby town and don’t have customer access at the winery. But the industrial look and feel of the cargo containers may detract from the romance that some wineries would like in order to promote a more sophisticated style to their retail customers. Nonetheless, someone with a good imagination and a saws-all could probably make an interesting tasting room out of a cargo container.

The narrowness of the containers with only one door at the end has the disadvantages of the LIFO (Last In First Out) storage. In certain cases cargo has to be handled several times, thereby using more time and energy.

Both barrels and pallets are a tight fit in the containers. Topping off barrels and retrieving buried case goods also takes up more time and energy than conventional building storage.

Despite their disadvantages, refrigerated cargo containers make a very viable alternative to traditional winery construction methods. We have saved considerably on permitting, construction, and cooling costs that have allowed us to spend the savings on necessary winery equipment. 

We have found the containers to be very usable and cost effective. We recommend this approach to other small wineries that want to avoid a large start-up cost and grow incrementally as their sales grow.