19, Jan 2016 / rebound


Back in August, I wrote about testing some customer hypotheses while waiting for Phase II of the NSF project to begin. Since then, we completed the MVP work and Phase II has begun.

After a few months getting the MVP reliably chilling a chest freezer in my garage, we deployed it at Whole Foods. As you’ll recall from the previous post, we wanted to use this MVP to validate our assumptions about our customers needs. We expected them to have four needs that IcePoint™ could address:

  • Offset electricity consumption by powering the system in part with waste heat
  • Shift peak electricity usage to lower cost off-peak hours
  • Eliminate EPA-regulated global-warming-causing refrigerants
  • Develop trust in new technology

Within two hours of arriving to install the unit, Marc Saba, the Sustainability Facilities Coordinator from Whole Foods, had validated #1 and #3 for us without any prompting!

As we walked through the mechanical room to install our system, we asked about the existing compressor rack. Marc launched into a story about how he had noticed the system was performing poorly so he had cleaned the condensers. Afterwards, the efficiency jumped, creating significant savings. This was great for us- they were already feeling the pressure of operating expenses and looking into improvements on their own.

Luke and Russell tell Marc Saba about the MVP.

Validating #2 is a bit trickier in Colorado. Marc didn’t express concern about avoiding peak electricity rates, because commercial time-of-use rates haven’t existed in the Rocky Mountain state. IcePoint™ can, however, help a grocery store avoid demand charges by reducing the the low-temperature refrigeration system electricity usage. With the proper control strategy this can provide real value. Rebound also recently discovered that Xcel Energy has implemented opt-in time-of-use rates. In the future, this experience indicates that we need to do more to show our customers how they can use IcePoint’s storage to take advantage of these savings opportunities.

Later on in the testing we learned about Marc’s experience swapping out compressor racks as regulations forced them to replace ozone-depleting refrigerants with modern ones. He was concerned, however, that in the next 10 years he would have to undergo this process again as pressure increased to replace global-warming-causing refrigerants. On top of having to go through the process, he was concerned that the newest refrigerants might not yet be ready for prime time since they haven’t been well demonstrated. There’s hypothesis 3 and 4 validated! We can help him swap those refrigerants for water based alternatives unlikely to ever be regulated. Plus, we mitigated some of his concern about implementing untested technologies by showing him that our technology was ready and reliable.

The MVP ran at the store through November. Ultimately, it did everything it was supposed to. It was powered by heat. It stored energy in ice. It used only water and ethanol – common fluids that are actually already sold in the store as beverages. And most importantly, it chilled the freezer case.