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LEED awards energy efficiency points based upon:

  1. Reduction in energy cost

  2. Reduction in energy usage

  3. Reduction of environmental emissions

  4. All of the above

Answer is :

a: Reduction in energy cost
What is the percentage of energy used in commercial buildings for lighting?
An Office building must supply at least 20 cfm of outside air per person if it is going to meet the Prescriptive Ventilation requirements of ASHRAE 62.1-2007

True or False?
False = the Minimum is 17 CFM
In Tampa Last month- April, the average temperature each day was 88 degrees. How many heating or cooling degree days is this?

Cooling days

88 - 65 = 23 cooling degree days per day

April has 30 days so

30 X 23 = 690

To Obtain LEED NC Certification level of Gold, the minimum point criteria is :

a) 41 points
b) 60 points
c) 83 points
d) 50 points

Certified 40–49 points Silver 50–59 points Gold 60–79 points Platinum 80 points and abov
Answer b - 60 points - LEED V3.0
Certified 40–49 points
Silver 50–59 points
Gold 60–79 points
Platinum 80 points and above
Which of the following is the correct conversion factor for barrels of Crude Oil to Million Btu:

a) 1 barrel = 2.6 MBtu
b) 1 barrel = 2.6 MMBtu
c) 1 barrel = 5.1 MBtu
d) 1 barrel = 5.1 MMBtu
d) 5.1MMBtu

In English units M= 1,000
MM = 1,000,000
E = I/d2
I   - Light Output
d - the distance from the light source to the         surface of interest.
E =  illuminance in footcandles

one footcandle is equal to one lumen per square foot.
________________ is the amount of light coming fromlight fixture that lands on a surface. It is
measured in Footcandles (Lux in the metric system).
The _____________ of a light source is a measurement of how welllight source represents color compared to an ideal source.
color rendering index
Color rendering index (CRI) is measured on a scale of _______ with Sunlight having a CRI of 100.
0 to 100
By measuring _____, we can compare the brightnesses of areas in a room, and determine_________ Ratios.
The __________of a surface is the percentage of light landing on a surface that is reflected outward.

typical white wall hasreflectance of around 70%, whiledark wood surface, such as cherry, hasreflectance of about 20%.
__________, commonly known as light fixtures, contain different lamp types which have different properties of illumination.
________ and ________lamps are the simplest type of lamp technology.

Tungsten-Halogen, Incandescent

They work by passing electricity throughfilament, which glows, producing visible light.
The light produced by tungsten-halogen and incandescent lamps has good color rendering  (about 99).

Tungsten halogen and incandescent are the least energy efficient of all typical light sources.
____________ produce light by passing electricity between two electrodes in a sealed tube. The resulting electrical arc produces UV light which excites phosphors on the tube,causing it to glow and produce light.
Fluorescent lamps

Fluorescent lamps are more energy efficient than tungston-halogen and incandescent
Fluorescent lamps usually havecolor rendering index of about____, and are typically ________ than incandescent luminaires.
85 , larger
________ are in the category of high-intensity discharge lamps (HID), and work in a similar process to fluorescent lamps.
Metal halide lamps

They are the most energy efficient of the lamp types used in architectural lighting.
Light levels are measures in _______ or _________ using a ______________ meter.
Footcandles,  Lux, Illuminance
Consensus standards for light levels are set by ___________________.
Illuminating Engineering Society of North America (IESNA.Org)
FC = lumens / ft2
Lux = lumens / m2

True or False ?

Average Rated life of a lamp is the ___________ of life expectancy of a group of lamps.
median value.
Time at which 50% have failed and 50% are surviving.

  • peak at peak cooling time

  • is sized to meet peak cooling load

  • may have the lowest efficiency at the time it is needed the most

Conventional Air Conditioning Operation


-______________systems are characterized by

  • CAC together with storage is used to meet peak cooling loads

  • Chilled water or ice is used for storage medium

  • Daytime peak load is reduced or eliminated

  • _______system operates at night when efficiencies are usually higher due to lower outside temperatures

Off-Peak Air conditioning Operations (OPAC)
What type of Air Conditioning Operation decouples the Load (Demand) from the Chiller (Supply) ?
Off-Peak Air Conditioning Operations
How do you calculate a Building Cooling Load Profile ?
Sum of the Load X hours

for example:

250T x 8 hrs,750T x 4 hrs,1000T x 4 hrs,750T x 4 hrs,500T x 4 hrs
Total  = 14,000 Ton-Hours
Where would we need to operate the chillers in order to satisfy the building load?
( assume load of 14,000 Tons-Hour & a Load leveling Strategy)
For load leveling strategy  chiller would operate 24 hours per day at a load of
14,000 Ton-Hours / 24 hours = 583.3 Tons.
Load Shifting means a complete shifting of peak hour AC load to Off-Peak hours.

True or False ?
It is usually more cost effective for retrofit situations because of large existing chiller load that can be mostly moved off-peak.
Where would we need to operate the chillers in order to satisfy the building load? 
( assume load of 14,000 Tons-Hour & a Load shifting Strategy)
For load shifting strategy  chiller would operate 16 hours per day at a load of 
14,000 Ton-Hours / 16 hours = 875 Tons. (Assume peak period from 12 - 8 pm leaving 16 hours to generate cooling capacity)
Chilled water storage requires approximately the same amount of space as Ice storage.

True or False?
Chilled water storage requires 4 to 5 times the space of ice storage.
Ice storage  requires more complex tanks and auxiliary equipment and is more complex to maintain.

True or False ?
Conditions that favor TES are
  • High peak demand charges
  • Low cost of energy used at night
  • High on-peak loads
  • Low AC loads at night
  • Need for increased cooling system capacity
a measure of warmth or coolness of a light source
Color Temperature

less than 3200k is warm or red side
greater than 4000k is cool or blue side
Chilled water systems store _________ Btu per pound of water for each `F of Temperature difference between the stored water and the return water
Ice systems use latent heat and one pound of ice at 32 F absorbs  ______ Btu to become 32 F water
Thermal Energy Storage (TES) systems yield large energy savings

True or False ?
With a load leveling TES strategy, a building manager will:

a) Not Operate the chiller during peak hours
b) Essentially base load the chiller ( i.e. operate at load most of the time)
c) Operate only during the peak times
d) Operate in the :off" season
b) Essentially base load the chiller ( i.e. operate at load most of the time)
A large commercial building will be retrofitted with a closed loop water to air heat pump system. Departments are individually metered. Demand billing is a small part of the total electrical cost. Would you recommend a TES?
TES favors High Demand charges so that load shifting or averaging can be employed.
Electricity production at or near the point of use, irrespective of size, technology or fuel used, both off-grid and on-grid. is known as _________
Distributed Generation (DG)
________________ produces both useful mechanical energy and useful thermal energy from a single system.
Combined heat and Power (CHP)

________________ is energy from natural resources, which are naturally replenished in the short term.
Renewable energy
- can be a form of DG
- Can be a central plant
- Can generate thermal and/or electrical
A Topping cycle CHP produces

a) Electrical energy first
b) Thermal energy first
c) neither
a) Electrical energy first
A Bottom cycle CHP produces

a) Electrical energy first 
b) Thermal energy first 
c) neither
b) Thermal energy first
How do you calculate the net reduction in annual energy cost delivered by a CHP facility?
  • Calculate the annual cost of fueling the CHP facility (i.e. 81,900 Mcf/yr @ $10/Mcf)
  • Calculate savings from Electricity offset.
  • Calculate savings from thermal offset
  • add offsets and subtract annual cost ( i.e. (480,000 + 357,143)- 819,000 = 18,143/yr
What is Net Metering?
measures the difference between the energy consumed from the utility and the energy produced by the generating equipment. Requires a meter with net metering capability
______________ represent the environmental attributes of the power produced from renewable energy projects and are sold separately from commodity electricity.
Renewable Energy Certificates
___________ is the process of ensuring that systems are designed, installed, functionally tested, and capable of being operated and maintained to perform in conformity with the designed intent.
The process of periodically repeating commissioning activities as needed when buildings are modified, additions are made and/or significant time has passed.
Recommissioning or Retro-commissioning.
Continuous monitoring of building systems to determine when further commissioning activities are needed.
Real Time Commissioning
Commissioning activities that occur seasonally. i.e pre-winter or pres-summer HVAC checks.
Seasonal Commissioning
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