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SkyCentrics CTA-2045 EcoPort and OpenADR Studies


Value of grid controlled, heat pump water heaters.

The story of July 15, 2019 CA ISO wholesale pricing is told to the left. Every day of July 2019 is below, showing the variability that would be missed by Time of Use schedules which change only every 6 months.

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Time of Use is a blunt instrument.
Daily schedule 'tweaks' are better.

The graph to the left is the CA ISO Demand and Net Demand curve for every weekday in the month of July 2019.

The goal is to chop off the peaks and fill in the lakes or ease ramps, but look at how they change every day!

  • Please focus on the side to side motion, as that shows need for daily schedule changes

  • Dark red = 3 hours of the steepest ramp.

  • Dark red often starts at 4:30 (hence a Time of Use schedule of 5-9 pm would be good)

  • But, it also starts on July 22 at 12;15 pm

  • July 23 at 2 pm

  • July 24 at 4:30 pm

  • July 25 at 1:45 pm

  • Pink ball = when ramp starts. See it move side to side.

  • Finally, the 'lake' or 'valley' that you would like to 'fill up' varies quite a bit also.

This shows that daily schedule 'tweaks' will lower grid costs and carbon emissions at a higher level than Time of Use.


July 2019 - T&D World Article on SkyCentrics OpenADR cloud and CTA-2045 EcoPort modules at Tucson Electric Power

Review of Project RAIN where the SkyCentrics OpenADR 2.0b Cloud VEN and SkyCentrics CTA-2045 EcoPort AC modules were used to control AO Smith water heaters (through the CTA-2045 module), and Ecobee thermostats through the Ecobee Utility REST API. The Smarter Grid Solutions OpenADR VTN sent signals to the SkyCentrics OpenADR VEN which then managed the water heaters and thermostats. The project was designed to explore how open standards can enable 'almost plug and play' Distributed Energy Resources (DER).

Standardized Communications for Demand Response Report - June 2018 - NRECA
An Overview of the CTA-2045 Standard and Early Field Demonstrations

Another strategy, beneficial or strategic electrification, emphasizes electrification opportunities that also reduce emissions, lower bills, increase grid flexibility, and improve energy efficiency. Many appliances that could be electrified, such as water heaters, space heaters, and vehicles are flexible loads. They present opportunity for storing excess renewable generation and may result in lower net carbon emissions if carefully implemented.

Orchestrating this storage or load shifting demands the two-way, reliable, and universal communications that the CTA-2045 EcoPort can provide. By monitoring end-use status in real time, co-ops can understand how much capacity they have to either add or shed load in response to excess generation or peak demand. This allows them to better prepare for these events and anticipate the result of an add or shed load period.

Benefits that manufacturers may realize from CTA-2045 may positively impact co-ops and their members as well. Open standards like the CTA-2045 EcoPort often encourage innovation, especially from smaller manufacturers, and can result in more choices to the consumer.

In addition, the modular approach of the CTA-2045 EcoPort may benefit end-product manufacturers by simplifying their product design and manufacturing. Rather than having to design the communications components into their products, they can rely on the expertise of the communications module manufacturer.


Bonneville Power Authority CTA-2045 Water Heater Demonstration Report

Site of the Bonneville Power Authority study on CTA-2045 EcoPort water heaters that led to the Washington state law SB 5115 requiring that all water heaters sold in WA state after January 1, 2020, must have a CTA-2045 EcoPort native on the water heater. Oregon has committed to joining Washington by January 1, 2022.


OpenADR presentation on CTA-2045 EcoPort water heater management and Ecobee thermostat management through API
for Tucson Electric Power's Project RAIN

Review of Project RAIN where an OpenADR VTN by Smarter Grid Solutions and an OpenADR 2.0b Cloud VEN by SkyCentrics use SkyCentrics CTA-2045 EcoPort AC modules and the Ecobee utility REST API to create almost plug and play Distributed Energy Resources (DER).


Duke Energy CTA-2045 EcoPort Presentation at ACEEE Hot Water Forum 2016

Duke Energy presentation shows the load profile of Electric Resistance and Heat Pump Water Heaters in the Florida climate zone. The value of Electric Resistance water heaters between 5-9 pm is about 0.2 kW each hour, and Heat Pump Water Heaters about 0.1 kWh each hour.

Jackson EMC CTA-2045 EcoPort Presentation at ACEEE Hot Water Forum 2016

Jackson EMC presentation shows the load profile of Electric Resistance Water Heaters in the Georgia climate zone. The value of Electric Resistance water heaters between 5-9 pm is about 0.3 kW each hour.


Heat Pump Water Heater Electric Load Shifting - A Modeling Study

Three water heater control strategies were analyzed: on/off, Load Up/Shed, and Optimal Price. Average customer bill savings ranged from 16-20%. Average utility savings ranged from 24-73%. This study was not intended to find the absolute maximum benefits to load shifting HPWHs, but to demonstrate that the benefit potential is significant. We trust that manufacturers and load management aggregators will create even more effective algorithms to maximize customer and societal benefits. To this end, the study was successful in demonstrating the savings potential of load shifting to both the utility and the customer.

Heat Pump Water Heater Demand Flexibility Study - Preliminary Results

Findings - Heat Pump Water Heaters can save customers 15-20%, and utilities/grid 35-60%, as well as lowering carbon emissions

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