QuantaCool Corporation

Advanced Thermal Management Solutions

Value of MHP™ Technology

Data servers account for about 40% of a data center's overall power consumption  ⁽¹⁾, and about half this power goes towards cooling, which is typically done by air conditioning the server rack rooms ⁽²⁾. This implies that cooling the servers accounts for about 20% of the overall power of a data center.  Assuming that 60 - 75% of the cooling power can be eliminated by direct heat rejection to air or water instead of air conditioning, this has the potential to cut the overall electric costs of data centers by 12 -15%.

The average operating power density for rack rooms in data centers is 179 watts per square foot ⁽³⁾.  At an average electricity cost of 8 cents per kilowatt-hour, the incentive for a 107,000 square foot (10,000 m²) data center to use direct-to-air/water server cooling is on the order of $ 2 million per year.

Where data center capacity is limited by the utility power supply, using QuantaCool's MHP^TM cooling technology instead of air conditioning the server rooms frees-up power to add ~15% more data servers, effectively de-bottlenecking the data center and allowing investment in new facilities to be avoided or deferred.

(1) See  http://searchstorage.techtarget.com/generic/0,295582,sid5_gci1247090,00.html

(2) Lawrence Berkeley National Laboratory  Final Report , Jonathan G. Koomey, "Estimating Total Power Consumption by Servers in the U.S. and the World", February 15, 2007

(3) See Table 1 of http://www.apcdistributors.com/white-papers/Cooling/WP-120 Guidelines for Specification of Data Center Power Density.pdf

Solar Concentrators (Concentrating Photovoltaics)

To reduce overall installation costs, it is advantageous to use concentrating photovoltaic (CPV) systems for solar electricity, since the cost per unit area of concentration devices (lenses, reflectors, etc.) is usually lower than the cost per unit area of active solar cells. 

However, increasing the concentration of the illumination also increases the heat load on the solar cells, and the electrical conversion efficiency decreases as the operating temperature of the cells increase.

Because of this effect, the there is a maximum concentration factor that can be achieved; above this maximum, the total electrical output of the cell decreases, due to the progressively lower efficiencies accompanying the rising operating temperatures.  The solar cells need to be cooled to maximizing the optimal concentration factor and minimize overall system costs. 

The optimal concentration factor for conventional passive cooling devices (e.g. finned aluminum blocks on the back of the solar cells) is on the order of 10x - 50x.  With active cooling, such as pumped water-cooled blocks, the concentration factor can be up to 200 - 500x, but at the cost of greater system complexity and lower reliability and higher maintenance costs; failure of the cooling system can result in severe overheating and possible damage to the solar cells.

In contrast, QuantaCool's MHP^TM cooling technology allows even higher heat removal rates than active water-cooled systems, with the reliability of a passive cooling solution.  Calculations indicate that optimal concentration factors in excess of 5000 suns should be feasible (see solar concentrator example) ; the concentration factor is limited by the physical constraints of the concentrator assemblies, rather than by the thermal load on the solar cells.  This has the potential to significantly reduce the cost-per-kW of solar power systems.