Case Studies in Energy Efficiency and Water Conservation Projects

Case Studies in Energy Efficiency and Water Conservation Projects

Introduction About PepsiCo World leader in convenient snacks, foods and beverages + $60 billion revenues + 285,000 employees Fortune 50 company About me Andy Lempera, PepsiCo Sustainability Director, PepsiCo America Beverages BS in Mechanical Engineering from Purdue University 1999 MS in Energy Engineering from UIC 2010 10 years as consulting mechanical engineer 7 years as sustainability engineer at PepsiCo PE in Illinois, LEED AP

Introduction Agenda 1. PepsiCo energy management program 2. Energy efficiency projects 3. Water conservation projects 4. Future efforts

PepsiCo Energy Management Program PepsiCo Energy Management Program

PepsiCo Energy Management Program PepsiCo Energy Management Program 1. Commitment (PepsiCo s PwP2.0-2015) Reduce GHGs by 20% by 2030 Reduce water use ratio by 25% by 2025 2. Assess Performance and Set Goals Glide path from 2015 to 2025 & 2030 3. Create Action Plan Capital projects and behavioral tactics 4. Implement Action Plan Annual sustainability budget Looking for new technologies that provide <~5 year simple payback Site visits 5. Evaluate Progress Monthly, quarterly, annual reviews 6. Recognize Achievements Part of annual bonus structure Annual competition between plants/region PepsiCo awards Energy Star Challenge for Industry

Energy Efficiency Projects Energy Efficiency Projects

Energy Efficiency Projects Condensing Economizer Captures latent heat from products of combustion in boiler exhaust stacks Increased η boiler from 83% to 95% (HHV) 8.0 MMBtu/hr of ~120 F water in this example Must have heat sink < 135 F Installed at nearly all plants with large low temperature heat sink

Energy Efficiency Projects Cogeneration 2700 hp CAT engine 2 MW generator (η elec =37%) 1,800 lb/hr steam (η steam =15%) 6.2 MMBtu/hr hot water (η hw =34%) η net =86% (HHV)

Energy Efficiency Projects Solar 3.5 MW solar PV Installed on roof of warehouse adjacent to processing plant

Energy Efficiency Projects Landfill Gas Cogen Landfill gas driven reciprocating engine Provides 1.6 MW electricity for the plant Provides 2,200 lb/hr of 160 psig steam for process Provides hot water to process η net =67% (HHV) Lighting Upgrades Replacing fluorescents with LEDs Draws a % of power as fluorescents while providing same or greater lumens Sometimes difficult to justify recent fluorescent installation Large effort across all plants

Energy Efficiency Projects Compressed Air Plant Upgrades After High speed magnetic bearing centrifugal compressors o Nearly zero energy used when unloaded o No oil in machine o Small footprint o No gears o Water-cooled VFD Piping modifications to reduce pressure drop Oversized filters Controller to avoid running compressors unloaded Monitor kw/100scfm (<20 typical) Before Before After

Energy Efficiency Projects Venturi Orifice Steam Traps Before: ~60% condensate return (failed traps, failed condensate pumps, flash losses) After ~90% condensate return Lifted condensate return instead of electric condensate pumps Flash occurs at central point & is captured at condensing economizer Thermal, water, electric and chemical savings

Energy Efficiency Projects Flash Tanks Capture flash from high pressure condensate and use as low pressure steam Saves water and fuel Variable Frequency Drives Use for modulating loads Power consumption % = (%speed) 3 Don t use for balancing only trim pump impeller or resheave blower

Water Conservation Projects Water Conservation Projects

Rainwater Capture 30 million gal/yr saved Water Conservation Projects A self-cleaning 200 micron filter removes fine particles. By opening the solenoid and turning on a brush cleaner the captured partticles and water are returned to the pond FT. PIERCE RAINWATER RE-CYCLE SYSTEM Originally coagulant was added prior to the UF skid. This was found to be unnecessary and eliminating it allowed for putting the normal backwashes back into the storm collection water system Permeate water is also used in backwashing the UF membranes Potable (City) Water serves as back-up supply to Rainwater Recycle system ULTRA- FILTRATION SKID EXISTING 20,000 GALLON TANK 5500 GALLON EVAPORATIVE CONDENSER MAKE-UP TANK Pond water is pumped out of pond at same location currently used by fire protection system which includes a double grate filter to keep out large particles Water is pumped both underground and then overhead (using an existing 4" SS pipe) in a pipe rack to the ultra-filtration module The ultra-filtration module removes organics and suspended solids. Normal backwashes are returned through the storm-water system. CEB s are sent to the site s waste water treatment plant (WWTP) After ultrafiltration, the permeate water is stored in an existing tank. The water is then sent through a softener and to the evaporative condenser makeup tank. The condenser water make-up tank supplies water to the evaporative condensers. The return water is monitored for conductivity and is bled off to the WWTP if conductivity is too high. The pond water has lower chlorides than the city water and is less corrosive to the condensers

Water Conservation Projects Sanitation Rinse Water Capture 5 MMgal/yr saved Converted UF from crossflow filtration to conventional filtration & eliminated concentrate to drain Reclaim UF backwashes & use at evaporative condensers

Energy Projects That Also Save Water Water Conservation Projects Condensing Economizer Condenses water vapor in combustion gases CH 4 + 2O 2 CO 2 + 2H 2 O + energy Water created can be used for cooling tower make-up Orifice Steam Traps Functioning traps prevent steam leaks Avoiding condensate pumps prevents failing pump seals Moving inevitable flash steam to boiler room makes it easy to capture and condense

Future Efforts Future Efforts More cogeneration, possibly with fuel cells More solar PV installations KPI monitoring for big utility users o o o o kw/ton and gal/ton-hr for refrigeration kw/100scfm and gal/ft 3 for compressed air kw/mmbtu and gal/mmbtu for cooling towers Solar thermal Recovery rates for water treatment More rainwater capture New technology?

QUESTIONS? Thank you! Andy Lempera andy.lempera@pepsico.com Case Studies in Energy Efficiency and Water Conservation Projects