PDX_05_Environmental Issues Rules Flashcards
BTU is energy needed to
Raise 1 pound of water 1°F
Raise 1 pint of water by 1°F
Standard measure used to state the amount of energy fuel has
as well as the amount of output of any heat generating device
British thermal unit
Typical furnace in the home puts out this range of BTU
80,000 to 150,000 BTU per hour
The person at rest puts out about _____ BTU per hour
250–350 BTU per hour
Typical US Home uses about this amount per year for space heating
50 million BTU per year
Design dry bulb for heating use is equivalent to
97.5% of the time
the outdoor temperature is above
the value listed on the table for the city
Design dry bulb for cooling use equals
2.5% of the time
the outdoor temperature is above
the value listed on the table for the city
Heating Degree Day is calculated by
The amount by which the average outdoor temperature is below 65°F for one day.
The more days it’s below, the larger number of degree days it has.
Phoenix equals 444
Anchorage equals 10,825
Heat flow =
Area/ R-value
To calculate parallel heat loss
(This much width) x (this much R-value)
+ (that much width) x (that much R-value)
Coefficient of performance:
Unitless measure of BTU/BTU or watt/watt
Psychometry:
Moisture, air, and heat interactions
As air temperature rises,
Capacity to hold moisture rises
Typical electrical production is __% efficient
33%
Typical vehicles are __% efficient
18%
