Small data centers
Small data centers tend to supply cooling with packaged DX air conditioners, also called CRAC units (computer room air conditioning). There are a few options for making these types of units as energy efficient as possible.
When purchasing the AC unit, many manufacturers offer variable-speed compressors that allow the unit to vary its cooling capacity to better suit changing load conditions, instead of running at full capacity even if the current load is low.
For data centers looking to improve the energy efficiency of the AC equipment they already have, Smartcool’s ECO3 offers an ideal retrofit option. The ECO3 is compatible with any 1 or 2 compressor CRAC unit, saving an average 15% kWh of the energy used by the system compressor.
Smartcool installed its ECO3 for PEER 1 data center in Vancouver, Canada. On two Liebert CRAC 3s, The two ECO3 units saved an average 13% or 18,407 kWh and gave PEER 1 a payback in 36 months. A similar project for Internet Solutions in South Africa saw the ECO3 produce energy savings of 14% kWh with a payback in under 12 months.
Energy savings are achieved with no impact to temperature or humidity- an incredibly important point for data centers where temperature control is critical to the business.
Large data centers
Larger data centers use chillers for a centrally controlled AC system. Purchasing a high efficiency variable frequency drive chiller with a condenser water reset tends to be the most energy efficient large-scale AC option for a data center.
Smartcool’s ESM is a highly successful retrofit for data center chillers, typically saving 8% to 12% kWh on the compressor operation. The ESM is a custom solution, that can be adapted to suit any control methodology, including advanced building management systems (BMS). It can also provide energy efficiency gains using an indirect interface (such as through the chiller manufacturer capacity control card), which preserves warranty conditions for the chiller.
Dell chose Smartcool’s ESM to improve the energy efficiency of the chillers in one of their Indian data centers. Savings of 16% were demonstrated and Dell saw a payback in just 21 months, all with no impact on temperature or humidity.
A general guide for other energy efficient measures in data centers is available from the US Department of Energy here.