Data Center Project Review
Technology Company Improves Energy Efficiency with “Free Cooling”
kW Engineering holds a unique role within the completion of energy efficiency projects in the service territories of PG&E and SCE in California. For the customized incentive process our engineers provide due diligence on behalf of the ratepayers, to ensure that incentives (i.e. rebates) are paid to projects that generate real energy savings. Since these programs are administered by the utility company, it is also important to keep the customers satisfied with the program so that their experience is a good one and they don’t hesitate to seek incentives for other energy efficiency projects at their facility.
As an example of how kW maintains these multiple goals, the following case study presents the experience of a local high-tech company in the San Francisco Bay Area.
A local database technology company in the East Bay, California considered adding economizers to their 16,500 square foot data center. Economizers provide “free cooling” for the facility by bringing in outside air when conditions are favorable, rather than using mechanical systems to cool re-circulated air. The project included installing controls and new ductwork to provide outside air to the datacenter on the second floor of their large, six story office building.
The utility company hired kW Engineering to evaluate the energy savings for the project and inspect pre- and post-installation systems. Prior to the retrofit, there were thirteen 20-ton Computer Room Air Conditioner (CRAC) units operating 24 hours per day, 7 days per week to maintain the temperature in the datacenter. A 240-ton chiller provided cooling for the CRAC units. The proposed system would route cool air during the economizer mode from two of six packaged rooftop units during non-business hours to reduce the cooling load on the chiller.
Energy Savings Estimation Approach
kW Engineering performed a site inspection and interviewed the Project Sponsor to gather data and calculate energy savings estimates. In the proposed system, when the outside air temperature was between 40ºF and 65ºF, the economizer would be used to route outside air to the datacenter. When the economizer mode of the CRAC units is enabled, mechanical cooling was to be locked out and the supply air will only be routed to the datacenter.
kW Engineers confirmed the operating characteristics of the proposed system and used data collected during the inspection to evaluate the annual load profile and energy savings for the project. Our engineers used a combination of the utility-approved energy savings estimation software and our own proprietary analysis templates to determine the energy savings.
Upon completion of the project installation, kW Engineering verified the installation and operation of the measure with a second inspection. During this inspection, we verified the new ductwork and controls for the cooling equipment in the datacenter and collected final cost information to determine if the measure cost cap would apply.
Results for the Utility
- A safe and thorough inspection and verification of an installed project by a licensed professional engineer
- Verified program energy savings of 297,776 kWh per year
- A well documented account of the project, with measurements and rigorous energy savings calculations to back up the savings claims.
- A customer who is satisfied with their experience with the utility’s energy efficiency program.
Results for the Utility Customer
- A $24,000 incentive from the local utility
- Independent confirmation of energy savings of 297,776 kWh per year
- Independent inspection of HVAC upgrades
- A positive experience with the utilities energy efficiency program.
kW Engineering's solid, engineering audit report and partnership helped us obtain a $250,000 grant that will allow our County to save over $130,000.”
— Malcolm R. Nash
Executive Administrator, Sevier County, Utah