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Cooling and Water

RDHx

Rear Door Heat Exchanger is a heat exchanger mounted on the exhaust side of a rack to remove heat before it enters the room. It can help densify air-cooled or hybrid deployments without fully converting to direct liquid cooling.

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Air permit

Air permit authorizes emissions from regulated sources such as backup generators, testing, fuel systems, or construction activities. Generator-heavy data center designs can make air permitting a material path item and community issue.

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Cap rate

Capitalization rate is NOI divided by asset value or purchase price. It is a shorthand valuation metric, but data center assets may trade on power availability, tenant credit, lease term, development risk, and growth options in addition to stabilized NOI.

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Wetlands

Wetlands are aquatic or saturated areas that may be regulated under federal, state, or local programs. A wetland constraint can affect developable acreage, mitigation cost, permit timeline, and transmission or access routing.

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