Executive Summary
This report refers to the performance trial of Coolnomix® energy saving optimizer for air conditioning unit undertaken at Safaricom base station in Rongai (13761_NE_NM1353- Nkoroi_OUTE_MGF).
The purpose of this trial was to perform a proof of concept and demonstrate that Coolnomix® can deliver energy savings of not less than 15% of the baseline consumption of the existing Air Conditioning unit.
Following two weeks of baseline measurements with Coolnomix® in bypass (Off) and another two weeks with Coolnomix® in control (i.e. Coolnomix® Switched ON), the average daily energy consumption taken over each period demonstrates an energy savings of 22.4% ± 4%. The data analysis represented a reporting confidence level of 75.8%
Analytical Method
The measurement and verification methodology option B was used in line with International Performance Measurement and Verification Protocol (IPMVP). This ensured that an isolation of the retrofit was done and consumption parameters recorded specifically on the power supply feeding the retrofitted AC.
Success Criteria
The trial was deemed a success under the following conditions;
- The sites’ thermodynamic conditions (Temperature and humidity) were to be maintained throughout the trial period.
- The retrofit was to have no degradation to the functionality of the existing AC.
- Demonstrate energy savings above 15% of the baseline consumption. A baseline report was thus generated upon the first two weeks of measurement with Coolnomix® in bypass.
Results
| Trial Period | Coolnomix in bypass (kWh) | Coolnomix Switched ON (kWh) | % Energy Saving |
| 12th April – 11th May | 125.69 | 97.52 | 22.4% |
During baseline data recording, the temperature of the AC units were set at 17⁰C. Temperature recorded over the two weeks period however averaged at 16.4⁰C. Data recorded during the next two week period when Coolnomix® was switched ON had temperature averaging at 17.4⁰C. This is because Coolnomix® was set 1⁰C above the AC temperature set point to ensure that Coolnomix® was in control of the existing AC cooling process when switched on.
Installation Pictures
Introduction
COOLNOMIX® ORS® is a patented algorithmic energy optimization control methodology, which stands for Optimized Refrigerant Supply. Incorporating two temperature sensors, it monitors the thermodynamic (room temperature) and the hydraulic (refrigerant supply) performance of the cooling system to eliminate periods of unnecessary work.
Objective
The main objective of this trial was to demonstrate that Coolnomix® can deliver energy saving of 15% – 30% of baseline energy consumption of an existing air conditioning unit.
It is to be noted that energy saving may vary between systems and across seasons, and achievement of energy saving is dependent on professional and regular maintenance and servicing of the installed cooling system.
Trial Setup
Eenovators team installed two Coolnomix® units each on the air conditioning units. The units installed with an external bypass switch to enable isolation of the optimizer units during the trial period.
Ambient temperature sensor was installed to monitor the indoor temperatures and an outdoor temperature probe to monitor the outside temperature.
Real-time energy monitoring systems were then integrated to enable remote data acquisition and close monitoring of the trial performance.
Test Result
With a reporting confidence level of at least 75.8% savings realized are estimated to be 22.4%
± 4%.
Regression Analysis
A regression analysis (R2 value) performed over the period of reporting indicates that 75.79% of the variation in energy consumption by the AC units can be explained by the outside temperatures.
Conclusion
There is a significant energy saving that can be realized by undertaking Coolnomix® retrofit on existing AC and a saving of 15% – 30% is achievable. In this trial, an estimated 22.4% ±4% was achieved with 75.8% confidence level. To further verify this, a proposal to have Eenovators undertake a pilot of a number of units in selected sites will be highly welcomed.
It is important to note that the savings achievable is depended on a number of factors such as proper sizing of the AC, maintenance and servicing condition of the AC, room occupancy (as this affects the thermodynamic condition of the room) and right refrigerant levels.
