Energy terms starting with U

39 terms

  1. U-Value (see Coefficient of Heat Transmission) The reciprocal of R-Value. The lower the number, the greater the heat transfer resistance (insulating) characteristics of the material.
  2. U.S. Environmental Protection Agency The independent federal agency, established in 1970, that regulates federal environmental matters and oversees the implementation of federal environmental…
  3. Ultimate Analysis A procedure for determining the primary elements in a substance (carbon, hydrogen, oxygen, nitrogen, sulfur, and ash).
  4. Ultraviolet Electromagnetic radiation at wavelengths shorter than 400 nm.
  5. Unconfined aquifer See Aquifer-unconfined
  6. Unconsolidated (basin fill deposits) Loose sediment; lacking cohesion or cement.
  7. Unconsolidated shore wetlands Includes all wetland habitats having three characteristics: (1) unconsolidated substrates with less than 75% areal cover of stones, boulders, or bedrock…
  8. Unconventional natural gas A term applied to natural gas that is difficult and expensive to find and produce; if found, it often is bypassed in favor of more easily obtainable…
  9. Underflow The movement of groundwater through the soil or a subsurface stratum, or under a structure; specifically, the water flowing beneath the bed of a stream…
  10. Underground Home A house built into the ground or slope of a hill, or which has most or all exterior surfaces covered with earth.
  11. Understory The trees and other woody species growing under a relatively continuous cover of branches and foliage formed by the overstory trees.
  12. Unfaulted An area without faults.
  13. Unglazed Solar Collector A solar thermal collector that has an absorber that does not have a glazed covering.
  14. Uniform Building Code (UBC) A building code published by the International Conference of Building Officials, adopted and amended by Oregon Department of Commerce.
  15. Uniform Mechanical Code (UMC) A code sponsored by the International Association of Plumbing and Mechanical Officials and the International Conference of Building Officials, adopted and…
  16. Unit (fuel or pulp) A bulk measure of hog fuel or pulp chips containing 200 cubic feet. A unit contains varying amounts of solid material depending on the amount of…
  17. Unit (timber) A timber harvest area with defined boundaries. The area is managed as a unit for harvest and subsequent management activities.
  18. Unitary Air Conditioner An air conditioner consisting of one or more assemblies that move, clean, cool, and dehumidify air.
  19. United States Code (USC) A compilation of the general and permanent federal laws of the United States. It is divided into 51 titles that represent broad areas subject to federal…
  20. Unmerchantable wood Material which is unsuitable for conversion to wood products due to poor size, form, or quality.
  21. Unrest (episode) Usually non-eruptive volcanic activity (e.g., ground deformation, steam plumes, degassing) that may be interpreted as a precursor to an eruption.
  22. Unstable slopes Slopes considered unstable due to their incline (or critical angle of repose), applied to slopes made of unconsolidated material.
  23. Unsuitable areas Areas not appropriate for timber harvest due to fragile or shallow soils, scenic values, special wildlife habitat areas, and riparian or wetland values…
  24. Unvented Heater A combustion heating appliance that vents the combustion by-products directly into the heated space.
  25. Upland The portion of the landscape above the valley floor or stream.
  26. Uplift Charges from an RTO/ISO collected outside of the market-clearing commodity price; these charges can include payments to reliability must run (RMR) units…
  27. Uplighting Light directed upward at greater than 90° above nadir, generally upward into the sky.
  28. Upper-air sounding An upper-air observation of the vertical profile of an atmospheric variable such as temperature or wind.
  29. Upwarp A broad anticline with gently sloping limbs formed as a result of differential uplift.
  30. Upzone To change the zoning of a tract or parcel of land from a lesser to greater intensity of usage.
  31. Urban Growth Boundary A line drawn around a city that prohibits development outside that boundary. Designed to slow or prevent sprawl, UGBs are designed to accommodate growth…
  32. uronic acid A simple sugar whose terminal -CH2OH group has been oxidized to an acid, COOH group.
  33. Usage charge A charge levied on power suppliers or their customers for the use of transmission or distribution lines and facilities.
  34. Use Value Taxation Land assessments according to the value of the present use rather than the speculative value.
  35. Useful Heat Heat stored above room temperature (in a solar heating system).
  36. USGS United States Geological Survey.
  37. USGS (United States Geological Survey) A federal agency which provides mapping of topography, aquifer levels, and areas where aquifers are recharged.
  38. Utility See Useful.
  39. Utility scale facilities Facilities that generate large amounts of electricity that is delivered to many users through transmission and distribution systems.