Western Cooling Challenge Updates
Munters EPX 5000 Dedicated Outdoor Air System (DOAS) Testing
We are currently compiling a report on the laboratory test results for a dedicated outdoor air system, the Munters EPX 5000. Initial laboratory results show a 20% energy reduction at peak conditions.
In conjunction with the laboratory testing, we are also instrumenting an EPX 5000 on a Whole Foods in San Ramon, CA and will be evaluating its efficiency during the 2014 cooling season. We are creating a scenario based comparison from our data that will model the savings of the EPX 5000 in conjunction with 5 RTUs versus a building with 6 RTUs and no EPX 5000.
Seeley Climate Wizard and the Coolerado M50 as a dedicated outdoor air system (DOAS) retrofit for a building with multiple RTUs
We are still analyzing the data from the installation and instrumentation of 2 Indirect Evaporative RTU retrofits (Seeley Climate Wizard and the Coolerado M50). This field test installs these add-ons on an RTU to effectively make that RTU a DOAS unit and therefore, allowing the other RTUs to only cool recirculated air. Initial results from these retrofits are promising, showing EER numbers greater than 40 during peak conditions. Both units run within the Cooling Challenge's guidelines for water use per capacity output.
In terms of proper installation, both Seeley and Coolerado do not offer a complete add-on package that controls the whole system. These control solutions are complex, and require engineers to get the systems up and running most efficiently. If the complexity of the controls are not properly resolved by the add-on manufacturer, this promising retrofit may find difficulty in reaching its marketplace potential. A full report on these two systems will be available in the near future.
Download the latest Trane DC Laboratory Results Report
Technology Demonstrations Update
RTU Retrofit using the Catalyst System
Drafting a Case Study on the Catalyst RTU retrofit system by Transformative Wave Technologies. At this time, WCEC only has 3 months worth of data (October-December).
- * One site at CSU Long Beach is showing an average electricity savings of the three months of study to be roughly 60%.
- * Another site located at CSU San Diego (SDSU) shows an average electrical savings of roughly 25%
Aeroseal Duct Sealing for Commercial Buildings
Currently analyzing data for the efficacy of sealing ducts in commercial buildings using Aeroseal at the Art Building at UC Davis. The sealing rate in this demonstration was approximately 80% of the leaks in ducts. Energy savings analysis due to the sealed ductwork will commence in the coming months.
Sealing leakage rate for the Art Building at UC Davis pre- and post Aeroseal application.
Aerosol Sealing of Building Envelopes Update
WCEC recently sealed the largest single-family home yet with aerosolized adhesives. The Honda Smart Home located in West Village at UC Davis, is a two story home approximately 2,000 square feet in size. The graph below shows the leakage rates of the home in a couple of different stages (ACH50 = Air Changes per Hour at 50 Pascals pressure):
The first stage (Pre Test 1), was tested while the house was still in the building phase just prior to drywall. The second stage (Post Test 1) shows the leakage rate after our first aerosol sealing treatment with our airless nozzle system. The third stage (Pre Test 2) shows the leakage rate after 3 contractors spent 8 hours each manually sealing the whole interior of the house. The manual sealing only shaved off another 0.05 ACH50 from the first Aerosol Sealing test. The fourth stage (Post Test 2) shows the leakage rate after WCEC replaced the airless nozzle system with an air nozzle system and sealed the house again with aerosolized adhesives--achieving a total leakage during very rough construction of 0.79 ACH50. After the construction of the home is completed, it is very likely that the house will reach the Passive House specification of 0.6 ACH50. We will be testing the final leakage rate after construction for the home is completed.
WCEC believes that current air nozzles work better than the airless nozzles we have tested simply because the velocity of air hitting the sealant helps to dry out and reduce the size of the particles, and the increased initial momentum may also increase the suspension rate/smaller particle size. To confirm this, WCEC has aquired a cascade impactor and will be testing particle size distribution for a variety of nozzles to determine the ideal nozzle system.