Patent Publication Number: US-10779440-B2

Title: Modular system for data center

Description:
This application is a divisional of U.S. patent application Ser. No. 12/568,323, filed Sep. 28, 2009, now U.S. Pat. No. 9,101,080, which is hereby incorporated by reference herein in its entirety. 
    
    
     BACKGROUND 
     Organizations such as on-line retailers, Internet service providers, search providers, financial institutions, universities, and other computing-intensive organizations often conduct computer operations from large scale computing facilities. Such computing facilities house and accommodate a large amount of server, network, and computer equipment to process, store, and exchange data as needed to carried out an organization&#39;s operations. Typically, a computer room of a computing facility includes many server racks. Each server rack, in turn, includes many servers and associated computer equipment. 
     Because a computing facility may contain a large number of servers, a large amount of electrical power may be required to operate the facility. In addition, the electrical power is distributed to a large number of locations spread throughout the computer room (e.g., many racks spaced from one another, and many servers in each rack). Usually, a facility receives a power feed at a relatively high voltage. This power feed is stepped down to a lower voltage (e.g., 110V). A network of cabling, bus bars, power connectors, and power distribution units, is used to deliver the power at the lower voltage to numerous specific components in the facility. 
     Computer systems typically include a number of components that generate waste heat. Such components include printed circuit boards, mass storage devices, power supplies, and processors. For example, some computers with multiple processors may generate 250 watts of waste heat. Some known computer systems include a plurality of such larger, multiple-processor computers that are configured into rack-mounted components, and then are subsequently positioned within a racking system. Some known racking systems include 40 such rack-mounted components and such racking systems will therefore generate as much as 10 kilowatts of waste heat. Moreover, some known data centers include a plurality of such racking systems. Some known data centers include methods and apparatus that facilitate waste heat removal from a plurality of racking systems, typically by circulating air through one or more of the rack systems. 
     The amount of computing capacity needed for any given data center may change rapidly as business needs dictate. Most often, there is a need for increased computing capacity at a location. Initially providing computing capacity in a data center, or expanding the existing capacity of a data center (in the form of additional servers, for example), is resource-intensive and may take many months to effect. Substantial time and resources are typically required to design and build a data center (or expansion thereof), lay cables, install racks and cooling systems. Additional time and resources are typically needed to conduct inspections and obtain certifications and approvals, such as for electrical and HVAC systems. 
     One problem that may be encountered in a data center is a fire. In some data centers, a fire that starts in one part of the data center is likely to spread to other parts of the data center. For example, a fire that starts in an electrical transformer or switchgear in a data center may spread to the entire data center, knocking out all the servers in the data center. Thus, a fire may carry a high cost, both due to equipment replacement costs and down time/loss of computing resources. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  illustrates one embodiment of a modular computing system. 
         FIG. 2  is an overhead view of a lower level of one embodiment of a modular computing system. 
         FIG. 3  is a side view of one embodiment of a modular computing system. 
         FIG. 4  is an overhead view illustrating an embodiment of an electrical module for a modular computing system. 
         FIG. 5  is an overhead view illustrating an embodiment of a data center module for a modular computing system. 
         FIG. 6  is a side view illustrating an embodiment of an air handling module for cooling a data center module of a modular computing system. 
         FIG. 7  is a side view illustrating an embodiment of an air handling module for cooling an electrical module of a modular computing system. 
         FIG. 8  is an overhead view illustrating an alternate embodiment of an upper level of a modular computing system including stand-alone evaporative cooling. 
         FIG. 9  is a schematic diagram illustrating one embodiment of a modular computing system data center module without a separate electrical module. 
         FIG. 10  illustrates one embodiment of providing computer resources with a modular computing system. 
     
    
    
     While the invention is susceptible to various modifications and alternative forms, specific embodiments thereof are shown by way of example in the drawings and will herein be described in detail. It should be understood, however, that the drawings and detailed description thereto are not intended to limit the invention to the particular form disclosed, but on the contrary, the intention is to cover all modifications, equivalents and alternatives falling within the spirit and scope of the present invention as defined by the appended claims. The headings used herein are for organizational purposes only and are not meant to be used to limit the scope of the description or the claims. As used throughout this application, the word “may” is used in a permissive sense (i.e., meaning having the potential to), rather than the mandatory sense (i.e., meaning must). Similarly, the words “include,” “including,” and “includes” mean including, but not limited to. 
     DETAILED DESCRIPTION OF EMBODIMENTS 
     Various embodiments of a modular system for a data center are disclosed. According to one embodiment, a modular computing system for a data center includes one or more data center modules having rack-mounted computer systems. An electrical module is coupled to the data center modules and provides electrical power to computer systems in the data center modules. One or more air handling modules are coupled to the data center modules. The air handling modules include at least one fan. The air handling modules provide air to at least one computer system in at least one of the data center modules. Modules of a system may be pre-fabricated prior to deliver to the data center site. In some embodiments, a modular computing system is a stand-alone, environmentally controlled computing system that requires only source electrical power and ambient air to operate. 
     According to one embodiment, a data center module includes a first data center module portion including a first row of racks of computer systems and a second data center module portion including a second row of racks of computer systems. The first computing module portion and the second computing module portion combine to form a computing space when coupled to one another. The modules may be pre-fabricated prior to deliver to the data center site. 
     According to one embodiment, a method of providing computing resources for a data center includes positioning one or more pre-fabricated data center modules at a site. The data center modules include rack-mounted computer systems. Pre-fabricated air handling modules including at least one fan are coupled to the data center modules. The air handling modules provide cooling air to computer systems in the data center modules. The pre-fabricated data center modules are operated at the site. 
     As used herein, “air handling module” means a module that provides air to one or more systems or components external to the module. 
     As used herein, an “aisle” means a space next to one or more racks. 
     As used herein, “ambient” refers to a condition of outside air at the location of a system or data center. An ambient temperature may be taken, for example, at or near an intake hood of an air handling system. 
     As used herein, “computing” includes any operations that can be performed by a computer, such as computation, data storage, data retrieval, or communications. 
     As used herein, “data center” includes any facility or portion of a facility in which computer operations are carried out. A data center may include servers dedicated to specific functions or serving multiple functions. Examples of computer operations include information processing, communications, simulations, and operational control. 
     As used herein, “computer room” means a room of a building in which computer systems, such as rack-mounted servers, are operated. 
     As used herein, “computer system” includes any of various computer systems or components thereof. One example of a computer system is a rack-mounted server. As used herein, the term computer is not limited to just those integrated circuits referred to in the art as a computer, but broadly refers to a processor, a server, a microcontroller, a microcomputer, a programmable logic controller (PLC), an application specific integrated circuit, and other programmable circuits, and these terms are used interchangeably herein. In the various embodiments, memory may include, but is not limited to, a computer-readable medium, such as a random access memory (RAM). Alternatively, a compact disc read only memory (CD-ROM), a magneto-optical disk (MOD), and/or a digital versatile disc (DVD) may also be used. Also, additional input channels may include computer peripherals associated with an operator interface such as a mouse and a keyboard. Alternatively, other computer peripherals may also be used that may include, for example, a scanner. Furthermore, in the some embodiments, additional output channels may include an operator interface monitor and/or a printer. 
     As used herein, “data center module” means a module that includes, or is suitable for housing and/or physically supporting, one or more computer systems that can provide computing resources for a data center. 
     As used herein, “electrical module” means a module that distributes electrical power to systems or components external to the electrical module. 
     As used herein, “evaporative cooling” means cooling of air by evaporation of liquid. 
     As used herein, “external cooling system” means a cooling system external to a modular computing system. For example, an external cooling system may be a chilled water system that is coupled to a modular computing system. An external cooling system may be located inside a facility or outdoors. 
     As used herein, a “free cooling” includes operation in which an air handling system pulls air at least partially from an external source (such as air outside a facility) and/or a return from a computer room, and forces the air to electronic equipment without active chilling in the air-handling sub-system (e.g., fluid flow through the chiller coils in the air handling sub-system is shut off by closing a flow control valve). 
     As used herein, a “module” is a component or a combination of components physically coupled to one another. A module may include functional elements and systems, such as computer systems, racks, blowers, ducts, power distribution units, fire suppression systems, and control systems, as well as structural elements, such a frame, housing, or container. In some embodiments, a module is pre-fabricated at a location off-site from a data center. 
     As used herein, “movable” means a component or combination or components having a container, housing, frame or other structure that allows the module to be moved as a unit from one location to another. For example, a movable module may be moved as a unit on a flatbed trailer. In some cases, a movable module may be attached to a portion of a floor, building, or permanent structure when deployed. For example, a movable module may be bolted to the floor of a data center facility. 
     As used herein, “power distribution unit” refers to any device, module, component, or combination thereof, that can be used to distribute electrical power. The elements of a power distribution unit may be embodied within a single component or assembly (such as a transformer and a rack power distribution unit housed in a common enclosure), or may be distributed among two or more components or assemblies (such as a transformer and a rack power distribution unit each housed in separate enclosure, and associated cables, etc.) 
     As used herein, a “rack” means rack, container, frame, or other element or combination of elements that can contain or physically support one or more computer systems. 
     As used herein, “mechanical cooling” means cooling of air by a process that involves doing mechanical work on at least one fluid, such as occurs in vapor-compression refrigeration systems. 
     As used herein, “source power” includes power from any source, including but not limited to power received from a utility feed. In certain embodiments, “source power” may be received from the output of a transformer. 
     As used herein, a “space” means a space, area or volume. 
       FIG. 1  illustrates one embodiment of a modular computing system. Modular computing system  100  includes data center modules  102 , air handling modules  104 , electrical module  106 , and air handling module  108 . Air handling modules  104  may each provide cooling air to one of data center modules  102 . Air handling module  108  may provide cooling air to electrical module  106 . 
     Each of data center modules  102  includes half module  102 A and half module  102 B. Each half module includes a row  116  of server racks. Each row  116  of server racks may include several racks  110 , each rack including several rack-mounted computer systems (for clarity, the computer systems are not shown in  FIG. 1 ). In one embodiment, each half module accommodates a row of 10 racks, for a total of 20 racks per data center module. In one embodiment, a modular computing system is sized in 20-rack increments, to a maximum of 60 racks (three data center modules) per system. In one embodiment, the overall size of a modular computing system is about 63 feet×26 feet (excluding generator). 
     Electrical module  106  may provide electrical power to data center modules  102 . Electrical conductors for distributing power from electrical module  106  to data center modules  102  may be provided in cables and/or buses running internal or external to the modules. In some embodiments, cables are provided through conduits or trays that run between the electrical module  106  and the various data center modules  102 . 
     In the system illustrated in  FIG. 1 , three data center modules  102  are shown. In other embodiments, however, a modular computing system may include only one or two data center modules, or more than three data center modules. In a similar vein, an electrical module for a modular computing system may be sized to support less than three data center modules, or more than three data center modules. 
     Each of air handling modules  104  provides air to one of half modules  102 A and one of half modules  102 B. Each half module  102 A and half module  102 B includes supply air opening  112  for receiving cooling air from its respective air handling unit  104 . Each half module  102 A and half module  102 B includes return air opening  114  for discharging air back to the air handling unit after the air has passed through server racks  110 . 
     In the embodiment illustrated in  FIG. 1 , one air handling module  104 , including air handling half module  104 A and air handling half module  104 B, is provided for both half modules  102 A and half modules  102 B of data center module  102 . Air handling half module  104 A and air handling half module  104 B may couple to form a common chamber. Air from fans  120  in air handling half module  104 A may mix with air from fans  120  in air handling half module  104 B. The mixed air from the air handling half module  104 A and  104 B may be supplied to data center module  102 , for example, via supply air openings  112  in half module  102 A and half module  102 B. In other embodiments, each of half module  102 A and  102 B may receive air from a separate air handling module. In certain embodiments, an air handling module may be coupled to, and/or provide cooling air for, more than one data center module. 
     In one embodiment, an air handling unit for a data center module is formed by combining two halves. For example, an air handling unit for data center module  102  may be formed from two halves, in which each air handling module half corresponds to one half modules  102 A and  102 B. 
     In some embodiments, each of half module  102 A, half module  102 B, air handling half module  104 A, air handling half module  104 B, electrical module  106 , and air handling module  108  are prefabricated modules. Each of half modules  102 A, half modules  102 B, air handling half module  104 A, air handling half module  104 B, electrical module  106 , and air handling module  108  may be separately transported to a site. For example, each of the modules or half modules may be transportable on a semi trailer. At the site, half modules  102 A and half module  102 B are coupled to form a data center module  102 . When half modules  102 A and  102 B are fully coupled to form data center module  102 , data center module  102  may become a sealed module. 
       FIG. 2  is an overhead view of a lower level of one embodiment of a modular computing system. Data center modules  102  and electrical module  106  of modular computing system  100  are positioned in line with one another. Each of half modules  102 A and  102 B of data center modules  102  includes row  116  including racks  110 . In the embodiment shown in  FIG. 2 , each of rows  116  includes 10 racks  110 . Row  114  may include any number of racks, however. In certain embodiments, each half module may include more than one row of racks. Air may be supplied from one of handling modules  104  to data center module  102  through supply air openings  112 . Air may be returned to an air handling module from data center module  102  through return air openings  114 . In certain embodiments, air discharged from racks  110  may be vented to ambient air. 
       FIG. 3  is a side view of one embodiment of a modular computing system. Data center modules  102  and electrical module  106  form a lower level of modular computing system  100 . Air handling modules  104  and air handling module  108  form an upper level of modular computing system  100 . Air handling half module  104 A and air handling half module  104 B are mounted on half module  102 A and half module  102 B, respectively. Air handling module  108  is mounted on electrical module  106 . Air handling modules  104  include fans  120 . Fans  120  may be operated to circulate air in data center modules  102  and electrical module  106 . 
     The number of data center modules deployed in a system may be selected based on the requirements of the data center. For example, if a data center in Facility A needs 38 server racks and Facility B needs 55 server racks, Facility A may be provided with two 20-rack data center modules (which could accommodate up to 40 racks total), and Facility B may be provided with three 20-rack data center modules (which could accommodate up to 60 racks total). In addition, over time, modules can be added to a modular computing system at a data center if the computing capacity needed at the facility increases, and modules can be removed from a modular computing system at the data center and redeployed if the computing capacity needed at the facility decreases. 
       FIG. 4  illustrates an embodiment of an electrical module. Electrical module  106  may be coupled to an external source of electrical power, such as a utility feed. Electrical module  106  may distribute electrical power to data center modules  102 . Electrical module  106  includes switchgear/mechanical distribution panel  124  and uninterruptible power supply (UPS)  126 . Although only one UPS is shown in  FIG. 4 , an electrical module may in some embodiments have more than UPS (for example, 5 UPSs). In certain embodiments, an electrical module for a module computing system may have no UPS. Service access to the components of electrical module may be through electrical module access doors  128 . 
     Electrical module  106  may house all of the electrical gear associated with the modular computing system. In one embodiment, electrical module  106  includes a 1600 amp ATS, 2. UPSs at 550 kW each, a critical distribution panel, main distribution panels, and a mechanical distribution panel. In some embodiments, electrical power at 480/277Y voltage is distributed to racks in data center modules. 
     Cooling air for components of electrical module  106 , including but not limited to uninterruptible power supply  126 , may be provided by air handling module  108  (see  FIGS. 1 and 2 ). Electrical module  106  includes electrical module supply air opening  130 , electrical module return air opening  132 , and exit air outlet  134 . 
     Electrical module  106  includes fire suppression system  136 . Fire suppression system provides fire suppression for electrical module  106 . In some embodiments, fire suppression system is automated. In one embodiment, fire suppression system  136  includes an FM-200 fire suppression unit. In certain embodiments, fire suppression system  136  is coupled to a control system for a data center. In one embodiment, fire suppression system controls dampers on supply air opening  130 , return air opening  132 , and exit air outlet  134 . Fire suppression system  136  may automatically close the dampers if a fire is detected in electrical module  106 . 
     Electrical module  106  includes backup cooling system  138 . In one embodiment, backup cooling system  138  includes an evaporative cooling system. 
       FIG. 5  illustrates an embodiment of a data center module for a modular computing system. Data center module  102  includes half module  102 A and half module  102 B. Half modules  102 A and half modules  102 B may be coupled together on site. Support columns  139  are provided at the junction of half module  102 A and half module  102 B. Half module  102 A includes row  116 A of server racks  110 A. Half module  102 B includes row  116 B of server racks  110 B. Rear aisle  140 A is behind row  116 A. Rear aisles  140  are provided in the space behind row  116 A of server racks  110 A and in the space behind row  116 B of server racks  110 B. The coupling of half modules  102 A and half modules  102 B forms joint aisle  142  between row  116 A and row  116 B. Support columns  137  may be provided between racks. 
     During operation of modular computing system  100 , air handling module  104  (shown in  FIG. 1 ) may supply air to data center module  102  through supply openings  112 . Air may flow from supply openings  112  into joint aisle  142 . Air from joint aisle  142  may pass through front  144  of server racks  110 A and server racks  110 B, pass over computer systems in server racks  110 A and server racks  110 B, and then exit the server racks through exit air devices  146  on back  148  of server racks  110 A and server racks  110 B. In some embodiments, exit air from various server racks  110 A mixes in rear aisles  140 . Air from rear aisles  140  may be drawn into air handling module through return opening  114 . In certain embodiments, an exit air device  146  isolates air exiting from one of server racks  110 A or server racks  110 B from the air in rear aisles  140 . For example, air from one of server racks  110 A or server racks  110 B may be ducted directly to air handling module  104  or vented directly to ambient air. In certain embodiments, exit air device  146  includes louvers. 
     Service access to the front of servers rack  110 A and server rack  110 B may be through data center module access door  150 . Service access to the back of servers rack  110 A and server rack  110 B may be through rack access doors  152 . In certain embodiments, rack access doors may be provided at both ends of the rack rows. For example, access doors could be provided under each of return air openings  114 . 
     In one embodiment, each half module  102 A and half module  102 B is not more than 9 feet wide×26 feet long×9 feet high. Each module may have the ability to house 10 racks in a hot row, cold row containment arrangement. In this example, the data center module has a capacity of 20 racks. In one embodiment, each rack is a standard size rack, which can either be straight from the vendor or built on site. In one embodiment, a rack is 24 inch by 40 inch by 70 inch rack, such as may be available from Rittal. Each data center module may have three points of egress, one per hot row and a third for the joint cold row. 
     In an embodiment, a data center module includes a 10 kW rack with a nominal usage range of 7.5-9.0 kW. The ambient temperature inside the data center module may be raised to 95 degrees Fahrenheit at the intake side of the rack. In one embodiment, the maximum load for the data center modules, electrical module, and air handling modules does not exceed 1 MW. 
     In the embodiment illustrated in  FIG. 5 , the form and fit of half module  102 A and half module  102 B are depicted as mirror images of one another. For example, supply air opening  112  of half module  102 A mirrors supply air opening  112  relative to the dividing line between half module  102 A and half module  102 B, and return air opening  114  of half module  102 A mirrors return air opening  114  relative to the dividing line between half module  102 A and half module  102 B (each of return air openings  114  being farther from the dividing line than supply air openings  112 ). In other embodiments, the form and fit of both halves of a data center module may be the same, such that one configuration of the half module can be used interchangeably in either position (that is, on either the left or right side). In one embodiment, supply air opening  112  is the same size and spacing as return air opening  114 , with suitable adapter plates and/or ducting provided in air handling modules to route air for insertion and removal at the appropriate locations in the data center module (for example, such that air is supplied to joint aisle  142  and removed from rear aisles  140  as described above). 
       FIG. 6  illustrates an embodiment of an air handling module for cooling a data center module. Air handling module  104  includes fans  120 , VFDs  121 , outside air vents  160 , return air vents  162 , return air damper  163 , filters  164 , and coil  166 . VFDS  121  may be coupled to fans  120 . VFDs  121  may be coupled to a control system for use in controlling fans  120 . In one embodiment, each air handling module  104  includes a single motor fan. The roofs on air handling modules  104  may have a slight slant to prevent water from standing on them. As illustrated in  FIG. 3 , each half module  104 A or  104 B may have two fans positioned alongside one another. An air handling module or half module may, however, have any number or configurations of fans. 
     During operation of a modular computing system, fans  120  draw air from outside air vents  160 , return air vents  162 , or a combination thereof and through filters  164 , and force the air into chamber  168 . Air flows from chamber  168  through supply vent  170 . Air from supply vent may pass into a data center module coupled to air handling module  104 . In one embodiment, coil  166  is coupled to a chilled water loop. Chilled water passing through coil  166  may cool air before it enters the data center module. In another embodiment, coil  166  is coupled to a tap water supply. In certain embodiments, air handling module  104  may include, or be coupled to, a mechanical cooling system and/or an evaporative cooling system. 
       FIG. 7  illustrates an embodiment of an air handling module for cooling an electrical module. Air handling module may be a construction that is generally similar to that of air handling modules  104 . Fans  120  of air handling module  108  may draw air front return air duct  180 , outside air vents  182 , or a combination thereof, and force air into chamber  184 , causing air to be supplied through supply air duct  186 , in a manner similar to that described above relative to  FIG. 6  for air handling module  104 . Air handling module  108  also includes a mechanical cooling system  190 . Mechanical cooling system  190  includes condensing unit  192 . Condensing unit  192  includes coils  194  and fans  196 . Condensing unit  192  may be operated on an as-needed basis to provide adequate cooling in electrical module  106  during various modes of operation. Condensor unit air exhaust may be vented through vent  198 . Air handling module  108  includes minimum outside air intake damper  200 . 
     In one embodiment, air handling module  108  includes 3 fans, 2 for mass air evacuation during the UPS charging cycle and a single fan to control basic module temperature. 
     Cooling components in air handling modules  104  and may be coupled to a control system. In some embodiments, a separate control system is provided for the electrical module and a separate control system is provided for each of the data center modules. Each control system may measure conditions such as temperature, pressure, flow rate, and humidity for the data center module, and adjust cooling system parameters for that data center module, such as fan speed, air source, mechanical cooling based on the measured conditions. In one embodiment, all of the air handling sub-systems and chilled-water sub-systems at a data center are controlled with a common control unit. In other embodiments, separate controllers are provided for each air handling sub-system and chilled water sub-systems, or for a subset of the air handling sub-systems and/or chilled water sub-systems. Devices in air handling sub-systems and chilled water sub-systems may be controlled automatically, manually, or a combination thereof. 
     In certain embodiments, a control system includes at least one programmable logic controller. The PLC may, among other things, open and close dampers in air handling modules based upon command signals from an operator to channel air flow through a data center module as necessary for the prevailing operational conditions. Alternatively, the PLC may modulate dampers between fully open and fully closed positions to modulate airflow. 
     Modular computing system  100  may include temperature measurement devices that, in one embodiment, are thermocouples. Alternatively, the temperature measurement devices include, but are not limited to, resistance temperature detectors (RTDs) and any device that facilitate cooling operation as described herein. For example, a chilled water thermocouple may be positioned within chilled water subsystem  138  to facilitate measuring a temperature of the chilled water upon discharge from a heat exchanger. In the one embodiment, such chilled water temperatures are controlled to within a desired temperature range or set point. Suitable set points or ranges may be, in some embodiments, between 5 degrees Celsius (° C.) and 28 degrees Celsius (° C.). 
     In various embodiments, operation of one or more air handling modules of a cooling system may be controlled in response to one or more conditions. For example, the controller may be programmed to switch the air source for an air-handling sub-system from return air to outside air when one or more predetermined conditions are met, such as temperature and humidity. 
     In some embodiments, air handling modules  104  and air handling module  108  operate only in free cooling mode, and no refrigerant cooling is used. In other embodiments, one or both of air handling modules  104  and air handling module  108  may operate in with refrigerant cooling, such as in locations with extreme humidity and heat. In some embodiments, air handling modules  104  and air handling module  108  may use evaporative cooling (either selectively or continuously during operation). 
     In some embodiments of a modular computing system, some or all of the modules may physically couple to one another. In certain embodiments, modules may be fastened together, such as by bolts or pins. In other embodiments, however, modules may not be fastened together, but simply be stacked or positioned next to one another. In some embodiments, adjoining modules may include aligning elements such as rails, pins, or keys. In certain embodiments, one or both of two adjoining modules, or two adjoining half modules, may include seal elements such that a seal is automatically made between the adjoining elements when they are coupled to one another. 
     In some embodiments, interface features of adjoining modules of a modular computing system are arranged such that electrical and/or cooling air connections are automatically made when the modules are coupled together. For example, when air handling module  104  shown in  FIG. 6  is coupled to data center module  102  shown in  FIG. 5 , a supply air opening  170  in each of air handling half modules  104 A and  104 B may align a corresponding supply air opening  112  in one of data center half modules  102 A and  102 B, and a return air opening  162  in each of air handling half modules  104 A and  104 B may align with a corresponding return air opening  114  in one of data center half modules  102 A and  102 B. Similarly, when air handling module  108  shown in  FIG. 7  is coupled to electrical module  106  shown in  FIG. 4 , supply air opening  186  of air handling module  108  may align with supply air opening  130  of electrical module  106 , and return air opening  180  of air handling module  108  may align with return air opening  132  of electrical module  106 . Thus, modular computing system  100  may be ready to operate as soon as air handling modules  104  are coupled to their respective data center modules  102 , air handling module  106  is coupled to electrical module  106 , and electrical connections made between electrical module  108  and data center modules  102 , without the need to install interconnecting ducts, for example, between modules. 
     In some embodiments, modules of a modular computing system may be spaced from one another. Connections between modules may be made with suitable ducts, conduits, electrical cables, buses, etc. 
       FIG. 8  is an overhead view illustrating an alternate embodiment of an upper level of a modular computing system including stand-alone evaporative cooling. Upper level  210  includes air handling module  212  and air handling module  214 . Air handling module  212  may provide cooling air for a data center module of the modular computing system. Air handling module  214  may provide cooling air for an electrical module of the modular computing system. Air handling module  212  is formed from air handling half module  212 A and air handling half module  212 B. Air handling half module  212 A and air handling half module  212 B form common flow chamber  215 . Fans  120  may draw air through return air opening  162 , outside air opening  216 , or a combination of both. Air may be drawn through filters  218  and evaporative cooling system  220 , and then forced into data center module through supply air opening  170 . In certain embodiments, a mechanical cooling system may be provided instead of, or in addition to, evaporative cooling system  220 . 
     In some embodiments, each of data center modules  102  and electrical module  104  includes a Supervisory Control and Data Acquisition (SCADA) and/or Building Management System (BMS). In one embodiment, the system measures the temperature of the air and other mechanical systems (UPS, switchgear, for example) at a regular interval and self-adjusts. If the SCADA system cannot make the appropriate adjustments, the system will automatically page system personnel. 
     In an embodiment, electrical module and data center modules in a modular computing system each include their own fire suppression system. If a fire starts in one of the data center modules, or another catastrophic event occurs, or if any other problem condition is detected in the data center module, the control system in that data center module may shut down the data center module. Shutting down the module may include, but is not limited to, closing dampers on all airflow openings in the data module to extinguish a fire. The electrical module and the remaining data center modules in the modular computing system may continue to operate while the damage data center module is serviced, or removed and replaced. In certain embodiments, electrical module and data center modules may include FM-approved insulation, in certain embodiments, a module may be FM-approved. 
     In some embodiments, a modular computing system is positioned in situ as a certified piece of equipment (rather than a permanent dwelling, for example). In some embodiments, each module, prior to shipment to the site, may be pre-certified by a Nationally Recognized Testing Laboratory. In certain embodiments, modules may be UL-listed and/or ETL-listed. A modular computing system, or portions a modular computing system may be ETL SEMKO, CE/ETSI, or UL stamped. In some embodiments, having a certified unit will reduce the scope of a building inspection. For example, the electrical inspector may only inspect the cable connections between the transformer/generator and the external panel on electrical module  106 , or the connections of any additional data center modules  102  added after the initial deployment. A modular computing system may thus in some embodiments be a self-contained system with the capability of rapid deploy, with only minor utility and fiber connections, which generally require only over-the-counter permits. 
     In some embodiments, some or all of the electrical components included in electrical module  106  described above with respect to (such as uninterruptible power supplies, switches) may be provided on board data center modules.  FIG. 9  is a schematic diagram illustrating one embodiment of a modular computing system data center module without a separate electrical module. Modular computing system  221  includes data center module  222  and air handling module  224 . Data center module  222  includes half module  222 A and half module  222 B. Each of half module  222 A and half module  222 B include rack-mounted UPS  226 , and distribution panel  228 . Distribution panel may include breaker  230 . Data center module  222  may be electrically coupled to source power. In certain embodiments, a UPS is provided at a server-level. In certain embodiments, a UPS may be omitted altogether from a modular computing system. 
     In the embodiments illustrated in  FIGS. 1, 2, and 3 , data center modules  102  and electrical module  106  of modular computing system  100  are positioned in line with one another. In other embodiments, however, data center modules may be arranged in different ways with respect to the electrical module. For example, an electrical module may be sandwiched between two data center modules. As another example, an electrical module may be surrounded by three or more modules (on all four sides, or on the west, north, and east sides, for example). In certain embodiments, space may be provided between an electrical module and a data center module, or between two data center modules. 
       FIG. 10  illustrates one embodiment of providing computer resources including a modular computing system. At  250 , a site for providing computing resources with a modular computing system is selected. In some embodiments, a site is an outdoor location. In other embodiments, a site is an indoor location, such as inside a warehouse. 
     At  252 , computing capacity needed for a data center is determined. At  254 , a quantity of data center modules for a computing system is determined from the required computing capacity. 
     At  256 , modules are shipped to the site. The modules may include data center modules, electrical modules, and air handling modules. Each module or portion of a module (such as half module  102 A) may be transported separately, such as on a semi trailer. In some embodiments, modules, or portions of modules, are pre-fabricated at one location, such as a factory, and transported to a data center site at another location. In certain embodiments, however, all or some portions of the modules for a computing system may be assembled at the data center site. For example, the two halves of data center modules may be coupled together at a site, racks may be installed in a data center module, or cooling systems, such as fans or evaporative coolers, may be installed in an air handling module. In some embodiments, the modules are pre-certified prior to shipment of the modules to the site. At  257 , the modular computing system may be operated to provide computing services for a data center. 
     At  258 , computing needs at a data center are reassessed. At  260 , additional modules may be transported and installed at the site based on the reassessment. In some embodiments, one or more data center modules are added to an existing modular computing system. 
     At  262 , conditions of data center modules and an electrical module in the modular computing system are monitored. At  264 , one of data center modules is shut down in response to a warning of a fire in the data center module. At  266 , a fire damaged data center module is removed and replaced. Data center modules other than the fire-damaged module may continue to operate while the fire damaged data center module is replaced. 
     Although the embodiments above have been described in considerable detail, numerous variations and modifications will become apparent to those skilled in the art once the above disclosure is fully appreciated. It is intended that the following claims be interpreted to embrace all such variations and modifications.