650,000 Square Feet

Located in in American Canyon - Near Napa - this is the 650,000 square foot wine transportation warehouse for which I designed the 55 degree cooling system. Energy saving strategies in the design yielded large savings in energy usage,  substantial PG&E rebates and help earn a LEED Silver certification. LEED = Leadership in Energy and Environmental Design. (Click photos to enlarge)

It all began with presentations of various designs and analysis of their up-front costs verses long term savings. Once the final approach was decided on, it was time to put it on paper.

[autocad drawing of the chiller system]

As I began drawing the system the site was being cleared for construction. Due to existing wetlands on the site the building shape and location were revised several times until it produced the least impact on the site.

[Google Earth screen capture]

In early March, 2009, I made a trip to the site:

[From the northeast corner looking to the opposite end of the floor slab 1/4 mile away]

[from the opposite end looking back towards the east end]

I found about one half of the east end wall erected.

The concrete wall slabs were manufactured in Santa Rosa and shipped to the site to save on construction time. Each slab has a number of hollow cores running through it making them much lighter than the poured in place slabs.

[A crane prepares to lift one of the slabs into position]

[As the slabs are stood in place another crew on the inside installs braces to stabilize them until the weld plates are completed]

Upon returning to the site for a meeting exactly four weeks later I was blown away to find the outside walls of the 1300' x 500' building completed.

[Looking east along the south wall]

The following five photos are a sequence of shots of the entire north wall:

[To get a feel for the scale, the dock door openings are 9 feet tall]

Not only was I shocked to find the walls up, but 2/3 of the roof was on also!

 [This area will later become the front office]

[From the east wall looking through the building to the west end 1/4 mile away]

The chiller pad with its pumps and evaporative cooling tower begins to take shape. This is the portion of the system depicted in the Autocad drawing at the beginning of this post.

[The cooling tower. A fan on top draws air through water flowing at 1,280 gallons per minute through the air stream, evaporating up to 600 gallons per hour thus cooling the water.]

 [Completed pump pad - composite of two photos yielded slight distortion at the center.]

The 500 ton centrifugal chiller. Freon is compressed in the centrifugal turbine and heated in the process due to compression. The hot freon is routed through tubes in the condenser barrel - the lower dome shaped item is the end of this barrel - where the heat is given off to the water which then circulates through the cooling tower to shed the heat. This in turn condenses the freon to a liquid still under high pressure. This liquid freon is then routed to tubes in the evaporator - the end of which is the upper dome shaped object. There it is dispersed through orifices where the resulting pressure drop causes the freon to evaporate to a gaseous state, taking on heat, thereby cooling the water in the evaporator. The chilled water is then circulated through Fan Coils within the building. The 500 ton rating means the chiller is capable of freezing 500 tons of ice in one hour's time. The system produces 1,340 gallons per minute of 35 degree water to feed the building. The first time I heard it start up I didn't know if I should run away or what - not unlike a 747 jet engine coming up to speed!

[The tank in the foreground is the oil cooler, above that to the right is the motor and to the left is the turbine]

[The fan coils. 30 inch fans throw the air out 100 feet. 48 of these in the building]

[The Variable Frequency Drive (VFD) which controls the chiller's turbine speed based on the cooling load]

[The VFD panels for the pumps and cooling tower mounted in the chiller house]

[Interior of the cooling tower VFD panel]

[VFD control panels for the Fan coils inside the warehouse. These also the front end controls to integrate the whole system as well as the controls for all of the office components - 5 rooftop air conditioning units with zone control damper systems.]

[Some of the fan coil VFDs. Due to the long wire lengths, filters were required to prevent interference and cross talk within the circuits. The capacitor assemblies are the filters]

 [LCD Readout of chiller parameters as it approaches its operating setpoint.]

The completed building and site. To the upper left is the rainwater detention pond, a long narrow area surrounded by levees, only partially filled at this point. It was completed after the rainy season, but in the future will collect all of the rainwater from the site and store it for reuse in irrigating the landscaping. Plants were chosen which are native to the area and require minimal amounts of irrigation. The areas to the right, above the building, are new venal pools, established to replace several which were lost to the construction of the building. These items, along with the air conditioning systems and motion sensors on all of the warehouse lights to keep them off when not needed are what accomplished the LEED Silver Rating. (Animal tracks radiate out from a watering hole on adjacent property next to the vernal pools.)

[Google Earth screen capture]