Twinwall in Real Life: Data Centers and Containment Systems

Data centers play a pivotal role in modern technologies that we all enjoy, especially those technologies which rely on cloud computing. "The cloud" may conjure up many different images based on your understanding of what the cloud is. Many see it as a metaphor, not a physical object. The reality is that these metaphorical clouds are indeed physical objects; rooms full of computer servers and battery racks placed inside containment systems (many times referred to as isolated hot aisles and cold aisles).

Large companies including Google, Amazon and Home Shopping Network have found that utilizing polycarbonate twinwall and polycarbonate multiwall in these containment systems provides the most reliable IT environments, allowing for maximum "uptime" as well as maximum cooling for servers and batteries alike, as well as physically separating groups of servers or batteries from each other.

The physical isolation of these servers, batteries and other systems provide many benefits, most notably temperature control, fire safety and contamination control.

Hot Aisles and Cold Aisles: Most servers and physical IT equipment will intake cool air from the front and exhaust hot air out of the back. If servers are placed on racks that face the same direction, the heat from the front most rack will flow to the intake of the next rack. As the air passes through each rack, it is further heated. This orientation for servers is unsustainable as the servers quickly become overheated.

The solution? Polycarbonate twinwall is used as a physical barrier to create literal aisles (walkways) that are set up to manage heat from servers. Server farm racks are lined up in alternating rows, where the front of the servers face each other creating a "cold aisle", and the exhausts from the server face each other creating a "hot aisle".

Separated by transparent polycarbonate twinwall, an HVAC (heating, ventilation and air conditioning) system will provide cool air through the cold aisles, and utilize return ducts in the hot aisles to recycle or exhaust warm air. The desirable thermal properties of polycarbonate twinwall allow the alternating cold and warm isles to sit side by side without significant heat transfer between the twinwall and multiwall sheets.

For companies like Google and Amazon, this method of cooling leads to significant savings. The Department of Energy asserts that when hot and cold isles are used in combination with containment systems including polycarbonate twinwall, a reduction in the need for electrical fans can see an energy savings of 20% to 25%.

Safety & Fire Containment: Polycarbonate twinwall and multiwall provide some of the highest flammability ratings, rated as a Class A interior surface material and classified as CC1 in accordance with ASTM D-635 and ASTM E-84.

This means server rows in hot and cold aisles may further be segmented and separated in containment areas that can be quarantined and minimize damage if a fire breaks out. This containment method not only protects other servers from catching fire, but can keep potentially explosive or hazardous systems from contamination. This is commonly seen when segmenting battery rooms from server racks, protecting the batteries and allowing them to provide power to other systems if one area becomes compromised.

The higher flame ratings that come with using polycarbonate twinwall and multiwall means lower insurance rates for data centers, further reducing costs while increasing safety.

Polycarbonate Twinwall Flammability Classifications & Ratings
Method	Classification*
BS 476/7	Class 1
DIN 4102	B-1 (10&16 mm)
NSP 92501	M-1, M-2
ASTM D-635 CC-1	CC-1
ASTM-E-84	Class A
EN 13501	B, s1, d0
*Classifications depend on sheet type/thickness.

Dust & Contamination Control: Polycarbonate twinwall can be surface coated with static dissipative ("anti-static") properties, further protecting IT systems contained within. Air moisture, pollution, airborne fibers and general dust are all potential contaminants to data centers, especially if built up over time. Polycarbonate twinwall not only resists many common acids, solvents and cleaning solutions; it can also fit into secure channels/profiles that create dust-proof barriers.

In much the same way polycarbonate twinwall separates hot aisles from cold aisles, it separates clean rooms or dust-free zones from contaminated areas, allowing little to no transfer of particles between walls.

For example, a fully enclosed data center can be created within a warehouse. Ducts are used in combination with an HVAC system to create a controlled environment without the need to fully retrofit an entire facility.

The right combination of features: It is not one feature, but the cumulative combination of specifications that make polycarbonate twinwall and polycarbonate multiwall a winner for data centers, server farms, battery racks, and other contained IT systems.

• Polycarbonate twinwall has superior thermal properties: the hollow fluted channels of twinwall create excellent thermal insulation, allowing two areas that greatly vary in temperature to sit side-by-side. These thermal properties lead to more efficient cooling in the summer and protection from the elements in the winter. A reduction in the need for fans in data centers can save companies as much as 20% to 25% on those electrical systems.
  

• Polycarbonate twinwall eliminates "hot spots" from external light, while still allowing light in: twinwall's transparency is desired because systems can be monitored from outside the contained area. With some materials this can cause "hot spots"; pockets of warm air within the area. When light from the sun or other UV sources hits polycarbonate twinwall, it is diffused and spread evenly over the sheet. This prevents "hot spots" from occurring, allowing for even cooling throughout the contained system.

• Polycarbonate twinwall provides lifelong protection: twinwall panels can be a permanent solution, and very rarely need to be replaced. They are stronger than all comparable materials and virtually unbreakable (even in extreme conditions from -40F to 240F), protecting the systems within. In addition, UV coatings protect sheets from yellowing and generally prevents more than a 4% decrease in light transmission over a 20 year period.

• Polycarbonate twinwall has stringent fire ratings that protect enclosed systems from cross-contamination.

For these reasons, polycarbonate twinwall has become a staple in both large and mid-size company's data centers and server farms. Polycarbonate twinwall provided by Interstate Plastics is cost-effective, lightweight, and extremely easy to machine, making it easy to set up for a multitude of designs and systems. Full sheets are available up to 10 feet long and 6 feet wide.

Learn more about the features, specs and benefits of polycarbonate twinwall, and call one of our plastics experts today at (888) 768-5759 to see how twinwall can be utilized in your next project!