Tech Analysis Exam Review

Decarbonization

Eliminating carbon release caused by the construction and operation of buildings' carbon footprint.

NET 0 Builds

Buildings that use or contain more carbon than they release and generate more energy than they use.

Embodied Carbon

Carbon emissions associated with building materials, including extraction, processing, manufacturing, shipping, and the construction process.

Operational Carbon

Greenhouse gas emissions associated with the ongoing and long-term operation and maintenance of a building, primarily from electricity generation and burning gas.

Heating Degree Days (HDD)

A metric indicating colder outdoor temperatures where space heating is needed.

Cooling Degree Days (CDD)

A metric indicating warmer outdoor temperatures where space cooling is needed.

Shoulder Seasons

Times of the year where heating or cooling requirements are not high, typically occurring when a building transitions between heating and cooling.

Passive Systems

Environmental control strategies that use natural design and physics without consuming energy, such as cross ventilation and solar gain.

Active Systems

Environmental control technologies that use powered mechanical devices requiring energy to run, such as heating equipment, cooling equipment, fans, and pumps.

Renewable Systems

Technologies that generate clean energy on site, such as photovoltaics.

Hybrid Systems

Systems combining active and passive techniques that require a small amount of energy to run, such as motorized louvers that track the sun.

Altitude

The height of the sun in the sky.

Azimuth

The angle of the sun measured from due north.

Global Horizontal Radiation (GHR)

All the solar radiation reaching a horizontal plane on Earth, represented mathematically as $GHR = DHR + DNR$.

Diffuse Horizontal Radiation (DHR)

Solar radiation reaching a horizontal plane solely by bouncing off the sky dome.

Direct Normal Radiation (DNR)

Solar radiation coming directly and uninterrupted from the sun.

Zone

A specific space within a building grouped by distinct thermal requirements based on schedule, use, or orientation.

Window to Wall Ratio (WWR)

The relationship of glazing to opaque wall in a façade, calculated by dividing total glazed area by total exterior wall area.

Energy Use Intensity (EUI)

A building's annual energy consumption report card measured per square foot or square meter of interior floor area.

Solar Heat Gain Coefficient (SHGC)

A metric that measures the fraction of solar radiation admitted through glazing.

U-Value

A measure of how well a building element lets heat pass through it, where a lower value indicates better insulating properties.

R-Value

A measure of how well an insulation material resists heat flow, where higher resistance values indicate better insulation.

Vacuum Insulated Glazing

A thin glazing option that provides very high U-values and good sound insulation, but costs $7$ times as much as double glazing.

PHIUS Requirements

Passive House US airtightness standard that uses surface area metrics and requires $0.060\text{ CFM50}$ per square foot of gross envelope area for standard projects.

Adiabatic Process

A thermodynamic change that occurs without any heat entering or leaving the system.

Adiabatic Boundary

An edge of a thermal zone that does not transfer any heat.

Horizontal Work Plane

The plane typically 2.5’ above FF

Decarbonization Stairway

A four-step performance and design sequence consisting of: 1. Reduce loads, 2. Passive systems, 3. Active systems, and 4. On-site Renewables (PV).

Universal Thermal Climate Index (UTCI)

The feels-like temperature combining air temperature, humidity, wind, and solar radiation.

Cubic Ft per Minute

How much air is moving in or out of a building each minute

UTCI

Real feel, OUTDOOR COMFORT