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DOE and the FTC Energy Guide

Department of Energy and the Uniform Energy Factor


The Department of Energy (DOE) Appliance Standards Program establishes and regulates the energy and water conservation standards established for certain consumer products and commercial and industrial equipment. All appliances that are regulated under the program must be tested and certified according to the standards established by the DOE.

Currently, DOE has no test criteria nor classification for the patented Quartz Infrared technology for heating water. Even the Certified Testing Laboratory we used for our Uniform Energy Factor (UEF) rating had no prior experience with Quartz Infrared technology and could only use the existing protocols issued by DOE for their testing, 10 CFR Appendix E to Subpart B of Part 430 - Uniform Test Method for Measuring the Energy Consumption of Water Heaters Sec 6.4.4. This test procedure assumes electric resistance heating elements and the published results are necessarily understated.

FTC Energy Guide

The FTC requires Energy Guides on a broad range of appliances, including water heaters. You will see the yellow Energy Guide Stickers on all storage tank water heaters, but the FTC only requires an Energy Guide for instantaneous electric water heaters with a power input
under 12 kW. Essentially, these are Point of Use water heaters.

As a result, there is no way to compare the annual operating cost of an electric storage tank water heater with a whole house electric tankless heater. Energy Guides on units with more than 12 kW power input is optional and voluntary and only a few manufacturers publish an energy guide for a unit with a power input of greater that 12 kW. (See the comparison below)

In spite of this, we have prepared this Energy Guide based on existing procedures and guidelines and according to the existing DOE formula, 
DOE430E2014_Eannual = 365 * ((V * p * Cp * 67) / (UEF)). It is accurate to the best of our knowledge. 
SIO 18 Pro Energy Guide

SioGreen SIO 18 Pro

Competitor's 18 kW Energy Guide
Competitor 18 kW Tankless
AO Smith 50 Gallon Tank Heater Energy Guide
Competitor 50 Gallon Tank 
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