April 18, 2014

Coolerado’s New Hybrid Wins Challenge

Coolerado’s New Hybrid Wins Challenge

By Rick Gillan

Old west meets new.  A team from California threw down a challenge last year to beat their idea of the best air conditioner for the West.  A Denver team called Coolerado accepts the challenge.  The showdown took place at the DOE lab this summer with Coolerado’s new hybrid commercial air conditioner delivering twice the target efficiency.

No kidding; Coolerado doubled the aggressive target efficiencies.  “While our target was a 40 percent reduction in energy use and peak electricity demand compared to conventional cooling units, the Coolerado H80 tests indicate almost 80 percent energy-use savings and over 60 percent peak-demand reduction,” said Mark Modera, director of the UC Davis Western Cooling Efficiency Center.

The “Western Cooling Challenge” was introduced at a Retailer Energy Alliance Supplier Summit hosted by the U.S. Department of Energy, and sponsored by the UC Davis Western Cooling Efficiency Center.  The challenge was to develop an air conditioner to more efficiently handle the severe temperatures and lower humidity of the western USA.  Two climate conditions were chosen for the challenge:

1.    Peak condition (similar to Phoenix, Arizona) at 105°F dry bulb (DB) and 73°F wet bulb (WB), with the return air temperature being 78°F DB and 64°F WB.
2.    Annual average condition (similar to Sacramento, California) 90°F DB and 64°F WB, with the return air temperature being 78°F DB and 64°F WB.

Additional test conditions beyond the standard require more than twice the downstream duct pressure, which increases fan power, and all power to be included.  The unit has to be able to dehumidify to meet the test conditions, but the targets do not allow the dehumidification portion to be used in the efficiency calculation.  Finally, aggressive water consumption limitations were set.

A summary of the results from the DOE-National Renewable Energy Laboratory technical report:

Challenge Coolerado H80
Peak Conditions:
105°F DB / 73°F WB
Downstream pressure: 0.7 inches of water column
Total Cooling: 36 – 360 61.7 kBTU/hr
Sensible Cooling: 56.9 kBTU/hr
Power: 2.84 kW
Total EER: 21.7 BTU/Wh
Sensible EER: ≥14.0 20.1 BTU/Wh
Outlet Humidity: ≤0.0092 0.00917 lb/lb
Water Use: 1.83 Gal/ton-hr
Surrogate Annual Conditions
90°F DB / 64°F WB
Downstream pressure: 0.7 inches of water column
Total Cooling: 57.4 kBTU/hr
Sensible Cooling: 45.6 kBTU/hr
Mean Power: 1.11 kW
Total EER: 51.8 BTU/Wh
Sensible EER: ≥17.0 41.1 BTU/Wh
Water Use: ≤4.0 1.85 Gal/ton-hr

Find the DOE Report, the UC Davis press release, the Coolerado press release and more at the Coolerado website by clicking here.

Coolerado is taking orders for the new H80 commercial hybrid unit now for delivery late this year.  Specifications for the H80 will be available on the Coolerado website by the end of August.  3D Drawing, Rev-It, and other files will be available mid September.