Definitions - t

Tail Boom

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Tailings

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Teratogen

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Thermal Break

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Thermal Comfort

The appropriate combination of temperatures, warm or cool, combined with air flow and humidity, which allows one to be comfortable within the confines of a building. This comfort is not usually achieved by the fixed setting of thermostats but through careful design and planning.

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Thermal Conduction

Thermal conduction is the transfer of heat (internal energy) by microscopic collisions of particles and movement of electrons within a body. In the building context this action is most often encountered when assessing how well a building can maintain its internal temperature in relation to the external temperature.

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Thermal Diffusivity

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Thermal Lag

Thermal lag describes a material's thermal mass in terms of time. A material with high thermal mass (high heat capacity and low conductivity) will have a high thermal lag. In effect the addition of (or removal of) energy from one side of the mass 'lags' with respect to the other side.


Thermal lag can be a useful feature, as for instance an outer brick wall on the Sunny Sunset side of a house in Winter would radiate its heat into the property in the evening, aiding with heating.

Thermal lag effects are often incorporated into good passive solar design for buildings.

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Thermal Mass

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Thermal Performance

Thermal Performance refers to how well a structure responds to changes in external temperature during the daily and seasonal cycles. Typically this is in relation to the thermal conductivity of materials or the assemblies of materials.

You want a property to maintain a steady comfortable temperature inside whilst incurring as little energy costs as possible; this is often best achieved by first improving the thermal performance of the property by providing high levels of insulation (high R-Value, low U-Value) on all surfaces and adopting passive solar techniques.


The thermal behavior of a structure is also affected by conditions such as:
  • seasonal and temperature changes,
  • daily diurnals (the difference between highest & lowest temperatures in a day),
  • the amount of solar gain and structural shading,
  • incoming and outgoing heat radiation,
  • water and moisture absorption,
  • air movement,
  • infiltration,
  • pressure differences, etc

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Thermal Pollution

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Thermal Resource

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Thermal Storage

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Thermohaline Circulation

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Thermosiphon

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Thunderstorm

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Tip Speed Ratio

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Topping Cycle

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Tornado

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Toxaphene

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Toxicity

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Trade Winds

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Treated Wastewater

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Tree Free

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Trickle Irrigation

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Triple Bottom Line

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Trisodium Nitrilotriacetate

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Trombe Wall

A Trombe wall is a very thick, south-facing wall, which is painted black and made of a material that absorbs a lot of heat (such as brick or concrete). A pane of glass or plastic glazing, installed a few inches in front of the wall, helps hold in the heat. The wall heats up slowly during the day. Then as it cools gradually during the night, it gives off its heat inside the building.

A Trombe wall is typically used in passive solar design to help improve energy efficiency of the building.

This article goes into more detail on how to use a Trombe wall and heat your home for free.

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Tropic Levels

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Tropical

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Tropical Storm Formation

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Troposphere

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Tuberculation

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Turbidity

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Tvis

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Two-Axis Tracking

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