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University of Tennessee Center for Industrial Services

Energy Assessments “Home & Business” Today’s Topics

➢HVAC ➢Insulation ➢ and Towers ➢Renewable Energy ➢Lighting Sources ➢Pumps & Motors ➢Solar Heating ➢Photovoltaic (solar cells) ➢Ventilation & Fans ➢Geothermal ➢Water Conservation 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 • Operations: 24 hours/day; 7 days / week • Electric rate: $ 0.095 per kWH • Annual Cost: a) $ 387 b) $ 775 $0.862 Per HP - Hr. c) $ 1,550 Correct answer d) $ 3,100 e) $ 6,200 Lighting Systems Quiz

• Quantity: (100) Halogen lamps & ballast • Operation: 400 (50 watt ballast); ½ day; 7 days • Electric rate: $ 0.095 per kWH • Annual Cost: a) $ 3,725 b) $ 7,550 $ 4.27 c) $ 11,575 per Hour d) $ 15,600 Correct answer e) $ 18,725 Lighting Project Example

• Quantity: (100) HBF Replacements • Operation: Lower ; no ballast; ½ day; 7 days • Electric rate: $ 0.095 per kWH • Annual Cost: a) less than $ 1,000 25 to 50% b) $ 1,150 LED Technology c) $ 2,300 164 Watts / unit Saved d) $ 4,680 $1.55 / hour Correct answers versus $4.27 / hour Correct answers e) $ 9,350 f) $11,890 Correct answers Energy Consumption

Integral Calculus: dy = ∫ (0.2345x6 + 12.099x5 - 212.93x4 + 1569.9x3 - 4770.2x2 + 7109.7x + 20920) dx Power Consumpon - Electrical Average Cost $ 44,000

$ 39,111

$ 34,222 HVAC Energy Consumption HVAC Cost $ 29,333 $90,000 Annual

$ 24,444 Air Handlers for the building $ 19,556 Power for Lights, Electronics, $ 14,667 Motors, and other Electrical $ 9,778 Systems

$ 4,889

$ 0 1 2 3 4 5 6 7 8 9 10 11 12 Jan Jun Dec Natural Gas - Heating

Consumpon of Natural Gas - Monthly Average Cost $ 17,000 y = -0.7312x6 + 30.397x5 - 486x4 + 3745.2x3 - 13965x2 + 20615x + 5194.2 R² = 0.9724

$ 12,750 Building Heat

Heating Cost $ 8,500 $26,900 Annual

Heat for Hot Water (Showers, $ 4,250 Kitchen, & Laundry) plus Heat for Laundry Dryers

$ 0 1 2 3 4 5 6 7 8 9 10 11 12

Jan Jun Dec Why are You Here?

“Tree Hugger”

“Don’t Know”

“Energy Strategy”

$$$$$$$ “High Cost of Energy” Introductory Perspectives

Transformations are generally:

• 10% concepts • 90% practical application – 20-to-1 payback • No expensive & advanced solutions – simple, effective, low-cost, and quick Introductory Perspectives

Not just about energy equations and numbers ! • People are greatest factor in saving energy

• People must be engaged and informed 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-excited people will contribute small energy-saving ideas

• When the most-excited people get involved, big energy 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 & (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, control, filtration, fresh air (), 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?

Heat Transfer & Heat Generation in Buildings

Monitoring, adjusting, and controlling HVAC systems achieve significant savings in your energy bill. Psychrometric Chart

Indoor 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 Chart

Tighter 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° summer example on next slide R 22 – Current $90 / lb.

“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 until 2020 but no R22 in new equipment after January 1,2010.” Why Care About Chillers and Cooling Towers?

• 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) Typical &

Typical cooling tower and chiller - commercial office building

Note: Municipal Buildings chillers and cooling towers generally larger “Air Cooled System” Boiling Point Heat Removal Varies based on (-46 to -35 deg C); ! “Condenser” Water freezes at 0 deg C

!High Pressure Hot Gas High Pressure ! Cool Freon “Reservoir” Liquid Gas Liquid Motor & 250 PSI 250 PSI 100 PSI Low Pressure Expansion Valve Motor Liquid/Gas Low Pressure ! Cold supply Hot Gas “ Process” “” WWWWWW WWWWWW Hot return “” Freon Boiling Point “Water Cooled System” Varies based on refrigerant (-46 to -35 deg C); Hot Water ! Return “Condenser” Water freezes at 0 deg C

!High Pressure Hot Freon High Pressure Gas ! Cool Freon “Reservoir” Liquid Cool Water Gas Supply Liquid 250 PSI 250 PSI 100 PSI Low Pressure Expansion Valve Liquid/Gas Motor Low Pressure ! Cold supply Hot Gas “ Process” “Compressor” WWWWWW WWWWWW Hot return “Evaporator” 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 energy bill by ½ Change the Operating Temperature

System Related Energy-saving Opportunities

• Overall System Savings if Reset/raise 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

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 Additional Opportunities Component Related Energy-saving Opportunities ! • Reduce Condenser Fouling - Fouling increases condensing temperature (condenser ) • 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 Types of Cooling Towers

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 ; • 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 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 Building with these systems don’t return a lot of the water to the sewer but they pay for the 5. 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

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 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 longer than 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

2 E = I / d 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 Indicates good - Standard "A" bulb energy - Tungsten halogen, & reflector efficiency for indoor lighting ➢ Fluorescent - Straight tube - Compact (CFL) ➢ High Intensity Discharge - Mercury vapor (MV) - Metal halide (MH) - High pressure sodium (HPS) ➢ Low pressure sodium (LPS)

➢ Light emitting (LED) (LEDs will be best in future) Light per Unit Energy

NOTE:

Some LEDs are 60 lumens per watt and

Lumens perwatt Lumens 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. • 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

2 E = I / d E = Illuminance (foot-candles or lux) Foot-Candles ~ Lux / 10 I = Intensity of lighting in candelas d = Distance from light source Exit Signs

• Other Types

Electroluminescent 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 – 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 (DC) Motor – Permanent on perimeter. DC goes thru . Rotor turns when magnetic field is reversed by switch.

• Basic AC Note: These – (AC) in are often called windings on . “Induces” “squirrel cage” (& hence this is called “induction”) motors because the inside rotor a magnetic field to turn the rotor turns similar to • ~100 % of building motors a circular cage are AC, so focus on AC motors turning when a squirrel runs in it Belts About 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 Belt Replacement / Maintenance

! ➢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 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- drives – electronic drives that vary the / frequency of the motor power. Improves power factor and provide performance benefits such as soft- starting or over-speed capability

Feedback Signal from Process

Regulator (Controls) Pressure Sensor

Converter Inverter (AC to DC) (DC to AC) DC Link

60 - Hz Adjustable Power Frequency Input Adjustable Speed Drive (ASD) and Voltage Motor Load (pump, etc.) Output 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

“No”

“Tees”

“Yes” “No”

“Elbows” “Yes”

1 inch 7 inches “Diameter Changes” “Yes”

“No” Inefficient Design

“No” Pipe 6 inches Diameter 18 inches Two Pipe Diameter Allowance

36 inches

18 inches 18 inches “Yes”

Pipe 18 Diameter inches Ventilation Fans • Change ( + or ―10%) in fan motor electrical usage check for clogged filters/ducts. !

! !

! !

Lessons: Regular filter change out; belts adjusted 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 Heating Payback 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 • 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 Heating Active 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 can be improved by heating domestic water by using otherwise idle collector during summer months. Solar Heating

Hot 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 for thermo-siphon flow Photovoltaic Interest Photovoltaic (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 Photovoltaic DETAILS of Photovoltaic Cell • 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 •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 (GHP) – pipes buried under near building, – plus heat exchanger and building ductwork. Questions?