cover image: Appliance Standards Awareness Project American Council for an Energy-Efficient Economy

20.500.12592/qh26n2

Appliance Standards Awareness Project American Council for an Energy-Efficient Economy

17 Jan 2023

The most common design has two sections of foam with a gap between the two pieces that allows one of them to be folded back onto the other.1 As DOE describes in the NODA, to address heat losses through the hinge, manufacturers may insert a third piece of foam to fill the hinge gap between the two cover pieces. [...] Given the sparsity of data for PES installations, DOE made assumptions in their analysis of the 2015 RECS data to estimate the probability a spa would be used X months per year as a function of climate zone.4 However, it appears DOE’s assumptions result in a meaningful underestimation of the annual operating hours of PESs. [...] While we acknowledge the sparsity of spa installation data in the 2015 RECS, we encourage DOE to use the raw 2020 RECS data, which features a much larger consumer sample,7 in determining the months per year of PES operation. [...] 2 Figure 1: a) The fraction of homes in the cold/very-cold climate zones with a given months/year of spa operation based on the NODA (yellow bars), the raw 2015 RECS data (purple bars), and the raw 2020 RECS data (green bars). [...] Thus, DOE assumes in the NODA that spas will be operated during the warmest months of the year.8 We are not aware of any evidence that would support DOE’s assumption and are concerned this assumption underestimates annual energy usage.9 Figure 1b plots the months per year of operation for spas in the cold/very-cold, hot-humid/hot-dry, and all climate zones based on the 2020 RECS data.

Authors

Jeremy Dunklin

Pages
4
Published in
United States of America