University of Tennessee Center for Industrial Services

Energy Assessments “Home & Business”

Today’s Topics➢HVAC ➢Chillers and Towers ➢Lighting ➢Pumps & Motors ➢Ventilation & Fans ➢Water Conservation

➢Insulation ➢Renewable Energy

Sources ➢Solar Heating ➢Photovoltaic (solar cells) ➢Geothermal

What is Energy Assessment…..

• Help understand energy use –Home or Business – what’s the difference? – Heating & Cooling • Electrical power • Natural gas

– Lighting systems – Windows and doors – Insulation & building envelops – Significant energy users

Why is it Important ……

• Significant increases in cost – Rising fuel surcharges – Vulnerable energy supplies – Population growth / limited supply – Environmental pollution – Simply the right thing to do – Economic benefit – monetary drivers

How do you accomplish …….

• Identify energy & waste – system waste = costs (needless) – improvement opportunities – planning - current / future strategies

• ID what to do, options & approaches • Plan / implement savings opportunities – Oriented to $’s, Pain, & Worry

Project Savings Quiz

• Quantity: (1) 5 HP electric motor • Operations: 24 hours/day; 7 days / week • Electric rate: $ 0.095 per kWH • Annual Cost: a) $ 387 b) $ 775 c) $ 1,550 d) $ 3,100 e) $ 6,200

$0.862    Per  HP  -­‐  Hr.Correct  answer

Lighting Systems Quiz

• Quantity: (100) Halogen lamps & ballast • Operation: 400 watt (50 watt ballast); ½ day; 7 days • Electric rate: $ 0.095 per kWH • Annual Cost: a) $ 3,725 b) $ 7,550 c) $ 11,575 d) $ 15,600 e) $ 18,725

$  4.27    per  HourCorrect  answer

Lighting Project Example

• Quantity: (100) HBF Replacements • Operation: Lower Watts; no ballast; ½ day; 7 days • Electric rate: $ 0.095 per kWH • Annual Cost: a) less than $ 1,000 b) $ 1,150 c) $ 2,300 d) $ 4,680 e) $ 9,350 f) $11,890

25  to  50%    Saved

Correct  answers

Correct  answers

LED  Technology  164  Watts  /  unit  $1.55  /  hour    

versus  $4.27  /  hour

Correct  answers

Energy Consumption

Power  ConsumpDon    -­‐  Electrical  Average  Cost

$   0

$   4,889

$   9,778

$   14,667

$   19,556

$   24,444

$   29,333

$   34,222

$   39,111

$   44,000

1 2 3 4 5 6 7 8 9 10 11 12

Power  for  Lights,  Electronics,  Motors,  and  other  Electrical  

Systems

HVAC  Energy  Consumption

Integral  Calculus:  dy  =  ∫  (0.2345x6  +  12.099x5  -­‐  212.93x4  +  1569.9x3  -­‐  4770.2x2  +  7109.7x  +  20920)  dx

HVAC  Cost $90,000  Annual

Jan Jun Dec

Air  Handlers  for  the  building

Natural Gas - HeatingConsumpDon    of  Natural  Gas  -­‐  Monthly  Average  Cost

$   0

$   4,250

$   8,500

$   12,750

$   17,000

1 2 3 4 5 6 7 8 9 10 11 12

y  =  -­‐0.7312x6  +  30.397x5  -­‐  486x4  +  3745.2x3  -­‐  13965x2  +  20615x  +  5194.2R²  =  0.9724

Building  Heat

Heat  for  Hot  Water  (Showers,    Kitchen,  &  Laundry)  plus    Heat  for    

Laundry  Dryers

DecJunJan

Heating  Cost $26,900  Annual

Why are You Here?

$$$$$$$

“Don’t  Know”

“Tree  Hugger”

“Energy  Strategy”

“High  Cost  of  Energy”

Introductory Perspectives

• 10%  concepts    • 90%  practical  application  

–20-­‐to-­‐1  payback   • No  expensive  &  advanced  solutions  

– simple,  effective,  low-­‐cost,  and  quick

Transformations  are  generally:

Introductory PerspectivesNot  just  about  energy  equations  and  numbers  !• People  are  greatest  factor

in  saving  energy

• People  must  be  engaged  andinformed  about  energy

• People  must  be  involved            at  all  levels  of  the  organization

People are the Most Important Factor for Saving Energy

• Some people are more excited about energy efficiency than others

• Even the barely-excitedpeople will contribute smallenergy-saving ideas

• When the most-excitedpeople get involved, bigenergy savings occur

• Energy teams of excited people are the best way to achieve energy savings.Each success occurs by doing an energy-saving event

Heating, Ventilation & Air Conditioning (HVAC)

Low-­‐cost  energy  solutions  with  high  payback

Definition

H  =  Heating   V  =  Ventilating   A  =  Air   C  =  Conditioning !!!Air-Handling units (ventilation) are covered later

Why Care About HVAC?

• HVAC  systems  provide  heating,  cooling,  humidity  control,  filtration,  fresh  air  (indoor  air  quality),  building  pressure  control,  and  comfort  control

• HVAC  systems  are  essential  for  employee  productivity  and  product  quality  

• HVAC  systems  are  the  single  largest  energy  expenditures  in  an  energy  bill  (approx.  50%)  for  buildings  

Why Care About HVAC?

Monitoring,  adjusting,  and  controlling  HVAC  systems  achieve  significant  

savings  in  your  energy  bill.

Heat  Transfer  &    Heat  Generation  in  Buildings

Psychrometric ChartIndoor  ASHRAE  Comfort  Conditions    (American  Society  of  Heating,  Refrigerating,  and  Air-­‐Conditioning  Engineers)

Note: See tighter comfort windows on next slide based on ASHRAE people survey.

Psychrometric ChartTighter recommended conditions for indoor comfort based on survey of people per ASHRAE Standard 55 Thermal Environmental conditions for Human Occupancy

Summarize as a Table of Indoor Comfort Conditions

70° winter 76° summerexample on next slide

“We  currently  have  AC  that  uses  R22.    What  are  requirements  and  what  actions  should  we  be  taking  to  change  over?”  

• Requirements  in  the  USA  (future)  from  EPA  website:    www.epa.gov/ozone/title6/phaseout/hcfcfaqs.html  

“You  can  still  use  R22  for  servicing  existing  AC  and  refrigeration  until  2020  but  no  R22  in  new  equipment  after  January  1,2010.”

R 22 – Current $90 / lb.

• Many  buildings  have  both  chillers  and  cooling  towers  

– chillers  and  cooling  towers  use  energy – opportunities  to  save  energy

• Chillers  

– Prevalent  in  office  buildings • largest  single  energy-­‐consumer   • large  motors  typical  (25  to  125  HP)

Why Care About Chillers and Cooling Towers?

Typical cooling tower and

chiller - commercial office building

Note: Municipal Buildings chillers and cooling towers

generally larger

Typical Chiller & Cooling Tower

Gas

Heat  Removal

“Compressor”

High  Pressure  !Hot  Gas

“Evaporator”

“Air  Cooled  System”

Low  Pressure  !Hot  Gas

High  Pressure  !Cool  Freon  

Liquid

Cold  supply

Hot  return

“  Process”

Liquid

Expansion  Valve

Motor  &  Fan

Motor

Freon  Boiling  Point    Varies  based  on  refrigerant  

(-­‐46  to  -­‐35  deg  C);  !Water  freezes  at  0  deg  C

Low  Pressure  Liquid/Gas

“Reservoir”

250  PSI250  PSI100  PSI

WWWWWWWWWWWW

“Condenser”

Gas

Hot  Water    Return

“Compressor”

High  Pressure  !Hot  Freon  

Gas

“Water  Cooled  System”

High  Pressure  !Cool  Freon  

Liquid

Liquid

Expansion  ValveMotor

Freon  Boiling  Point    Varies  based  on  refrigerant  

(-­‐46  to  -­‐35  deg  C);  !Water  freezes  at  0  deg  C

“Reservoir”

250  PSI250  PSI100  PSI

Cool  Water  Supply

“Evaporator”

Cold  supply

Hot  return

“  Process”

Expansion  Valve

Low  Pressure  Liquid/Gas

250  PSI100  PSI

WWWWWWWWWWWW

Low  Pressure  !Hot  Gas

“Condenser”

Example – Efficiency Savings• Energy Efficiency (COP = 4) versus (COP = 2)

Calculation Basis: • 100 ton chiller operating 8,700 hours (round the clock) • 6 cents per KWh, • electric motor • 1 KWh = 3,413 BTU’s per hour

• COP = 4; annual operating cost = $45,900 • COP = 2; annual operating cost = $91,800

Double  the  COP;  cut  the  ener

gy  bill  by  ½  

System  Related  Energy-­‐saving  Opportunities  

• Overall  System  Savings  if  Reset/raise  Chilled  Water  Temp  (continued)  

– Chiller  water  is  raised  to  54  °F  (OK  for  HVAC)  instead  of  typical  ARI  settings

– Compared  to  44  °F  setting……   –  (54  -­‐  44)  =  (10  °F)  x  (2  %  savings  per  °F)  =  20%  energy  savings  !!!  Also,  chiller  COP    improves  linearly    by  increasing    chilled  water  T  

Change the Operating Temperature

Case Study: Freon Leaks• County Justice Center:

– Fouled Exchanger – High Compressor Head pressure – Freon 22 Leaks – Constant recharging – Older unit with some age – replacement

• One time savings of $24,000 (R-22 cost) • Efficiency gains with new unit - $14,600 • Potential Savings: $38,600

Component Related Energy-saving Opportunities !• Reduce Condenser Fouling

- Fouling increases condensing temperature (condenser heat exchanger) • Treated water to avoid water mineral salts deposition on tube walls • 1 degree rise = 1% decrease/loss in full load rating • System works harder to achieve same cooling results

• Maintain Proper Condenser Flow Rates – 20% Reduced flow increases energy by 3% – Reduce Condenser Water Temperature – Each degree reduction save 1.5% on operating cost

• Check for ΔT between cooling tower and condenser, should be < 2 °F difference • If >2°F above incoming cooling tower temperature; identify and correct

– Cooling tower bypass mixing warm return water with condenser discharge (startup or cold weather )

– Pipe insulation can also be a problem

Additional Opportunities

Air-to-water flow – 2 types: (1) Cross-flow: Air flow perpendicular to water flow.

– Air flow enters vertical faces of the cooling tower – Meets fill material. – Hot water gravity flows from distributor through fill. – Air continues through the fill into open plenum. – Cold water to basin – pumped back to process.

(2) Counter-flow: – Counter-flow design, air flow opposite water flow. – Air flow enters open area beneath the fill – Air drawn vertically through tower fill. – Water sprayed through nozzles into top of fill;

gravity flows downward opposite to air flow. – Cold water to basin – pumped back to process

(3) Induced draft – typically pull-through system

Types of Cooling Towers

• Cooling towers use water in 3 ways(1) Evaporation, (2) Drift, and (3) Bleed-off !

• This figure illustrates water use in a typical cooling tower.

1. Evaporation (E) controlled by thermodynamics; • Water evaporation removes heat • 1200 lbs/hrs = 100 tons of cooling; 2.4 gpm of water !

2. Bleed off (B) – removes mineral salts / solids • Evaporation doesn’t remove salts / dirt / dust • Water typically high in Calcium Carbonate - limestone • Salts collect on cooling surfaces if not removed • Also known as “blow-down” – similar to boilers ops !

3. Drift (D) – function of design • Typical is 0.05 to 0.2% of tower water lost to drift • Entrained water droplets out top of tower • Caused by upward lift of air flow !

4. M (makeup water) = E + B + D 5.

Types of Cooling Towers

Building  with  these  systems  don’t  return  a  lot  of  the  water  to  the  sewer  but  they  pay  for  the  sewer  cost  nonetheless.

Water Consumption Case Study

• Municipal Water Supplies – Cooling Towers - (2) for Building – Supporting (2) 300 ton Chillers for building –

50% – Approximate Water Supply needed:

• Evaporative Losses – 2.4 GPM Water per 100 tons cooling • Blow down on tower – 1 to 2% of water supply • Drift from tower – 0.2% of water Supply

– Water Flow Daily: 10,000 gallons 2.4 x 24 x 60 x 3 / (1.022) – Sewer Cost being paid as well

Can  you  see  where  the  water  Increases  in  the  summer  months?

Estimated  Savings  Potential  Here  =  $4,250

Energy-­‐saving  Opportunities  for  Cooling  Towers

• 2  Biggest  Problems  for  Cooling  Towers  

– The  two  biggest  problems  with  cooling  towers  are:        1)  poor  performance  –  inadequate  cooling      2)  premature  tower  failure  –  corrosion,  wood  deterioration,  rot,  fouled

– Both  adversely  affect  energy  consumption.   • Routine  tower  maintenance  

• Water  treatment  program  normally  avoids    problems  

• Consult  supplier’s  maintenance  manuals  for  recommendations

Energy-saving Opportunities

Energy Efficient Lights

A short-course in

low-cost energy solutions that provide high payback

Why Care About Lights?

• Energy efficient lights use up to 75% less energy than standard lighting, produce 75% less heat, and last up to 10 times longerthan standard lights.

Energy-saving Opportunities•Locate light fixtures near/above the work area where light needed

•Light level reduces as the square of the distance E = I / d2 E = Illuminance (foot-candles or lux) Foot-Candles ~ Lux / 10 I = Intensity of lighting in candelas d = Distance from light source

Types of Lights➢ Incandescent

- Standard "A" bulb- Tungsten halogen, & reflector

➢ Fluorescent - Straight tube - Compact fluorescent lamp (CFL)

➢ High Intensity Discharge - Mercury vapor (MV)- Metal halide (MH) - High pressure sodium (HPS)

➢ Low pressure sodium (LPS)

➢ Light emitting diode (LED) (LEDs will be best in future)

Indicatesgoodenergyefficiency for indoorlighting

Light per Unit EnergyLu

men

s pe

r wat

t

NOTE: Some LEDs are 60 lumens per watt and 131 has been achieved in labs so expect LEDs to be the best in future years

Incand.  –  Incandescent   LED  –  Light  Emitting  Diode   MV  –  Mercury  Vapor  MH  –  Metal  Halide   HPS     High  Press  Sodium     LPS  –  Low  Press  Sodium

Trends for Lights➢ Incandescent Being phased out by Energy Independence

and Security Act of 2007 – “EISA” – (Energy Bill)

Signed into law December 18, 2007 ➢ All light bulbs must use 25% less energy than today’s incandescent bulbs by the year

2015. ➢ The phase-out will start with 100 watt bulbs in January 2012 and end with 40 watt bulbs in

January 2014. Phase in 2012 to 2014 – specialty bulbs exempted ➢ By 2020, law requires all bulbs to be at least 70% more efficient (effectively equal to

today’s CFLs energy consumption).

Light Controls• Benefits of controls for lights can be significant

- Energy reductions by as much as 75% by using skylights and dimmable lighting controls.

• Electric Power Research Institute (EPRI) estimated savings by using light controls – offices (25-50%) – rest rooms (30-75%) – corridors (30-40%) – storage areas (45-65%) – meeting rooms (45-65%) – and warehouses (50-75%)

Lighting Example

Example:  Hallway  (Corridor)  Lights  ➢ 25  fixtures  operating  24/7  @  $0.06  /  kWh  ➢ Each  fixture  equipped  with  (4)  32  watt  T-­‐8’s  ➢ Electronic  ballast  !            kWh  =  365  x  24  x  32  x  4  x  25  /  1,000                                =  28,032,000  /  1,000  =  28,032  kWh  !Cost  Saving  Potential  =  28,032  x  0.35  x  0.06  =  $590  annually

Light Controls• Types of Light Controls

- Timers - Occupancy Sensors- Photocells - Dimmers - Energy Management System (EMS)

Skylights for Indoor Lighting

• Natural lighting - Skylights can be effectively used in many workplaces such as warehouses (right) and retail stores (below)

Exit Signs• Incandescent

- In traditional exit signs, a single exit sign can be $33 per year. The cost of replacement lamps and the labor to install them can add up to $24 per year per sign.

• LEDs - LED exit signs use only 1 to 5 watts of power per surface and cost less than $5 per year to operate. Because LEDs also last much longer than incandescent lamps, lifecycle savings are available.

• Photo-luminescent- Photo-luminescent materials absorb and re-radiate light, so these types do not require electrical power (ZERO energy use). Must conform to National Fire Protection Code and UL requirements (UL924 ) that these must maintain particular levels of visibility for at least 90 minutes after other sources of light have been extinguished.

Physically “Lower the Lights”

!• To increase lux (or foot-candles), consider moving light

fixtures lower (if currently in a high ceiling) to be closer above the work area/desks/benches. !– extend the wires/conduit to hang the lights lower

– install a false ceiling (suspended tile ceiling). • can also accomplish HVAC savings by reducing heat load

Energy-saving Opportunities•Locate light fixtures near/above the work area where light needed

•Light level reduces as the square of the distance E = I / d2 E = Illuminance (foot-candles or lux) Foot-Candles ~ Lux / 10 I = Intensity of lighting in candelas d = Distance from light source

Exit Signs• Other TypesElectroluminescent panels: not as good as LED or photo-luminescent for exit signs. Cold cathode fluorescents: not as good as LED or photo-luminescent for exit signs.

Exit Signs Comparison of Light Sources for Exit Signs

Lighting Case Study• Attic Space Lighting– On when no one there

– Annual Operating Costs: $2,460 • High Traffic areas – less light needed

– Switch from T-8 Technology to LED – Annual operating savings: $8,840

• Parking Lot Lamps: Mercury Vapor – $4,100 annual operating cost – Switch to exterior Energy efficient lighting – Annual operating savings: $2,000

• Annual savings potential: $13,300

Energy Efficient Motors & Pumps

Low-cost energy solutions that provide high payback by

saving energy in all facilities at manufacturers, offices, etc.

Why Care About Motors?

➢Motors are everywhere ➢Fans, pumps, conveyors, anything that moves/turns, etc.)

➢50% of U.S. electricity in offices flows through a motor. ➢64% of U.S. electricity in industry flows through motors

Motor Basics• Basic Direct Current (DC) Motor

– Permanent magnet on perimeter. DC goes thru rotor. Rotor turns when magnetic field is reversed by commutator switch.

• Basic AC Induction Motor – Alternating current (AC) in

windings on stator. “Induces” (& hence this is called “induction”)a magnetic field to turn the rotor

• ~100 % of building motors are AC, so focus on AC motors

Note: These are often called “squirrel cage” motors becausethe inside rotorturns similar to a circular cageturning when a squirrel runs in it

Motor Drive BeltsAbout one-third of electric motors use belt drives • V Belts

– Most common type. – 98% efficient new; drops to 93% due to wear after initial installation (5% loss) – Pulley size, driver torque, under/over-belting, belt design/construction causes – V-belts lose efficiency dramatically at high torque – increased slippage !

• Cogged Belts – Slots perpendicular to belt’s length used with the same V belt pulleys – Reduce bending resistance – conform better with less slippage – Run cooler, last longer, and 2% better efficiency

• Synchronous Belts – Aka, timing belts – Positive-drive, high-torque, spline belts and pulleys. – 98% efficient over wide load range. – Synchronous belts – less maintenance and re-tensioning, wet or oily environments,

slip-free (until they fail) – Noisy, unsuitable for shock loads, and transfer vibrations. – 5% more energy efficient than V belts

!➢10 or 20 to 1 payback typical ➢ For Example:

➢25 HP motor; 24 / 7 @ $0.06 per kWh ➢5% of annual cost = 5% x $9,800 = $490 ➢Cost of belt and installation = $25 - 50

Belt Replacement / Maintenance

Adjustable Speed Drive• Adjustable-speed drives (ASDs)

– electronic or mechanical devices for motors designed for single-speed operation to drive a load at variable speeds.

• Variable-frequency drives – electronic drives that vary the voltage / frequency of the motor power.

Improves power factor and provide performance benefits such as soft-starting or over-speed capability

Regulator(Controls)

Converter(AC to DC)

Inverter (DC to AC)

60 - Hz Power Input

DC Link

Adjustable Speed Drive (ASD)

AdjustableFrequency

and Voltage Output

Motor Load (pump, etc.)

Pressure Sensor

Feedback Signal from Process

Replace Motor, not Rewind• All new motors sold in US are high efficiency.

– Older standard efficiency motors generally rewound and reused.

• Rewinding costs less but re-wound standard motors are 5% to 8% less efficient than high efficiency motors (EPACT or NEMA).

Motor Replacement Advice

• Standard (old technology) motors 50 hp or smaller – High runtime (> 3,000 hours per year), – Replace with more efficient NEMA , before (old) motor fails – Payback usually less than 3 years (33% ROI)

• Standard (old technology) larger motors > 50 hp – Replace at failure – Larger motors generally more efficient – Replacement not economically justified till failure

Energy Strategy for Motors• Highest efficiency

– operate motors preferably at/above 85% of full load, and definitely at/above 50% of full load.

• Motor efficiency drops off steeply for operation below 50% of full-load, or when the motor is idling.

• The energy efficiency strategy – choose the right-size, energy-efficient motor & marry it with an optimized drive systems

Building Ventilation & Fans

!

Low-cost energy solutions with high dollar payback

“Tees”

“Elbows”

“Diameter  Changes”7  inches

1  inch

“No”

“No”

“No”

“Yes”

“Yes”

“Yes”

Pipe    Diameter 18    

inches

“No”6  inches  

Inefficient  Design

18  inches   18  inches

Pipe    Diameter

18    inches

36  inches

“Yes”

Two  Pipe  Diameter  Allowance

• Change ( + or ―10%) in fan motor electrical usage check for clogged filters/ducts.

! !! !!

Lessons: Regular filter change out; belts adjusted

Ventilation Fans

Water  Conservation  Practices

Case Study: Water Conservation

• Justice Center Water Bill – total for facility – Average monthly cost in past years: $4,500 – Current average cost in past year: $9,000 – Low to no change in number of inmates – No change in the pricing for water

• Annual savings potential: $120,000 – Find source of problem and correct (cause was

a faulty water meter……) • Lessons Learned: “Monitor billing closely”

Graphs  are  Excellent  Ways  to  see  Trends  and  Changes

General Notes on Insulation• Double paned windows are 50% more energy efficient than

single paned units • Triple paned windows are 90% more energy efficient • Adequate insulation in attic spaces above rooms can lower

energy usage by as much as 30% – Minimal depth of blown insulation is six inches

• Crawl space insulation under floors can lower energy usage by as much as 35%

• Walls and windows the remainder (about 35%); windows perhaps as much as 1/3 the wall loss if not thermally efficient

General Notes on Insulation• Wall insulation is much harder to install after

building construction – Possible but expensive

• Sealing windows and doors with weather stripping can significantly reduce energy cost – Especially with public buildings

• Isolating a building entrance from the main halls and offices with a second set of doors to the building can lower energy usage.

!

Renewable  Energy  

Solar  Heating,  Photovoltaic,  Geothermal,  etc.

Solar HeatingPayback usually 3 to 5 years (after tax credits) !• Heat Buildings

– Passive solar design • Specially designed windows, walls, and floors • Collect, store, and distributes heat energy in winter • Reject solar heat for summer

– Active solar heating • Collectors to absorb solar radiation, • Transfer the solar heat directly to an interior space or to a storage system • Heat transfer fluid can be liquid (water, glycol, etc.) or air.

• Hot Water – Solar water heating systems include storage tanks and solar collectors - (2 types) – Active - circulating pumps & controls, and passive, which don’s – ~ 60% to 80% efficient at energy conversion to hot water

Solar HeatingActive solar heating

– Savings depend on climate –Reduce heating bills by 50%

DETAILS

– Pre-heat air as it enters a building – Most economical in cold climates with good solar exposure. – Cost variation

• Larger systems cost less per unit of collector area • Commercial systems installation range from $30 to $80 per square foot of collector area • Commercial collectors - 10 year warranties or more • Economics of an active space heating system can be improved by heating domestic water by using otherwise idle collector during summer months.

Solar HeatingHot water (active or passive), • Hot water bills should drop 50% - 80% • Cloudy days - partially pre-heat water

entering conventional hot water tank

• Active system- Has circulating pumps & controls

• Passive thermo-siphon- No circulating pumps or controls, so water tank must be above solar panel for thermo-siphon flow

Photovoltaic InterestPhotovoltaic (PV) – Solar Energy

Panels – US locations get enough sunlight – payback in about 5 years (after tax

credits); service life = 25 years

Tennessee: ~ 5 kWh/m2/day solar output ➢ One Panel: 4x8 panel ~ 3 square meters ➢ 20% efficient panel – that’s about 3-4 KW a

day (will power a 100 watt bulb for about 35 hours)

➢ Best in class – Sharp – record holder

PhotovoltaicDETAILS of Photovoltaic Cell • Semiconductor panel absorbs light • Panel typically converts 10%-18% to kW

– 44.4% in laboratory (achieved May 2013) – materials science & design are keys – 100 square yards needed for a home

• Energy to usable DC Current electricity •Energy to Power Inverter •Production of AC voltage for use •A typical small office = 35 kWh per day.

+ -­‐

Building Schematic

(Typically:  4x8  ft.  Panels)

Rise of Geothermal……!•GHPs  reach  high  efficiencies    (300%-­‐600%)  on  cold  days •Compare  to  conventional  pumps   175%-­‐250%  •  GHPs  use  25%–50%  less  electricity  •  Drawback  -­‐  GHPs  typically  cost                              twice  conventional  systems      •As  GHPs  interest  increases,  costs  will  come  down,  so  payback    should  improve  in  the  future

Geothermal• All US locations • Payback less than 5 years - > 20% • Unit wise – about same cost – installation

is more expensive..... Exclusive of the field line

•  Anywhere  there’s  a  sufficient  soil  layer  

•  Upper  10  feet  of  the  earth's  surface  has  nearly  constant  temperature  of  50  -­‐  60°F  

•  Geothermal  heat  pump  (GHP)    

–  pipes  buried  under  ground  near  building,   –  plus  heat  exchanger  and  building  ductwork.

Questions?