Effective Energy Management

Effective Energy Management

Effective Energy Management

1. Develop baseline

2. Identify and quantify savings opportunities

3. Measure and benchmark to sustain efforts

1. Energy Use Baseline

–Billing analysis• How energy is priced

–Plant energy balance• Where energy is used

– Lean energy analysis (LEA)• What drives changes in energy use

Utility Bill Analysis

Analyze rate schedule Verify billing amounts Check for saving

opportunities:– Primary/secondary– Power factor correction– Meter consolidation– Demand reduction

potential Benchmark costs

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Plant Energy Balance

Equipment Rated Power Frac Loaded Oper Hours Elec Use(hr/yr) (kWh/yr)

AC #1 50 hp 90% 5,000 187,500Lights 10 kW 100% 6,000 60,000… … … … …Other 10,000

Utility Bill Total = 257,500

Equipment Rated Input Frac Loaded Oper Hours Gas Use(Btu/hr) (hr/yr) (MBtu/yr)

Boiler 1 1,000,000 70% 5,000 3,500Make Up #1 500,000 100% 2,000 1,000… … … … …Other 500

Utility Bill Total = 5,000

1) Estimate energy use from:

• rated power• frac loaded• operating hours

2) Calibrate sum against measured total energy use

Energy Use Breakdowns by Equipment

0% 12% 24% 36% 48% 60%

Vacuum PumpsProcess Blowers/Fans

LightingDust Collectors

SandersOther Process Motors

Air CompressorsProcess Heating

Other

20%

18%17%

12%12%

8%6%

5%

2%

Estimated Electrical Use Breakdown

Lean Energy Analysis

Understand what drives changes in Energy

Quantify “Waste” and “Lean”

Model: Energy = a + b Production + c Weather

Source Data

Date Elec (kWh/dy) Nat Gas (mcf/dy) Prod (units/dy) Toa (F)1/31/2002 76,127 590 13,065 34.72/28/2002 80,564 581 13,557 34.73/31/2002 77,362 542 12,401 39.44/30/2002 81,712 418 14,086 53.55/31/2002 80,059 348 14,181 58.66/30/2002 90,094 298 13,439 72.57/31/2002 86,361 287 10,551 77.48/31/2002 89,326 341 14,239 75.89/30/2002 95,441 348 13,830 69.710/31/2002 82,779 434 12,693 51.511/30/2002 77,639 535 12,977 39.612/31/2002 61,288 518 9,982 30.7

Actual Temperature Data

http://academic.udayton.edu/kissock

Plot Fuel vs Toa

Model Fuel Use vs Toa: 3PH

R2 = 0.92

HS

Find

Tcp

Model Fuel Use vs Production: 2P

R2 = 0.02 Prod Slope Negative

Model Fuel Use vs Toa and Prod: 3PH-MVR

R2 = 0.97 Prod Slope = Positive

Disaggregate Fuel Use

Weather = 28%

Production = 58%

Independent = 14%

Temperature

Fuel

Model Electricity vs Toa: 3PC

R2 = 0.67

Model Electricity vs Production: 2P

R2 = 0.32

Model Electricity vs Toa and Prod: 3PC-MVR

R2 = 0.82

Disaggregate Electricity Use

Weather = 10%

Production = 39%

Independent = 51%

Temperature

Electricity

Lean Energy Analysis

Called “Lean Energy Analysis” because of synergy with “Lean Manufacturing”.

In lean manufacturing, “any activity that does not add value to the product is waste”.

Similarly, “any energy that does not add value to a

product or the facility is also waste”.

Quantified “Leaness” of Fuel Use

Weather28%

Production58%

Independent14%

“Independent” is a metric of energy not added to productFuel LEA = %Production + %Weather

Fuel LEA = 86%

Quantified “Leaness” of Electricity Use

Production39%

Independent51%

Weather10%

“Independent” is a metric of energy not added to productElectricity LEA = %Production + %Weather = 49%

Electricity LEA = 49%

Average LEA Scores (%P+%W)(28 Manufacturing Facilities)

39%

58%

Use Lean Energy Analysis To Discover Savings Opportunities

LEA Indicators of Savings Opportunities– High “Independent” indicates waste– Departure from expected shape– High scatter indicates poor control

Low Electric LEA = 24%Indicates Operating Opportunities

Low Fuel LEA Identifies Insulation Opportunities

High Heating Slope Identifies Heating Efficiency / Insulation Opportunities

High Data Scatter Identifies Control Opportunities

Heating Energy Varies by 3X at Same Temp!

Departure From Expected Shape Identifies Malfunctioning Economizers

Air conditioning electricity use should flatten below 50 F Audit found malfunctioning economizers

Lean Energy Analysis

Quick but accurate disaggregation of energy use: – Quantifies the energy not adding value to product or

the facility– Helps identify savings opportunities– Provides an accurate baseline for measuring the

effectiveness of energy management efforts over time.

2. Identify and Quantify Saving Opportunities

Identifying energy savings– Use “Integrated Systems + Principles Approach (ISPA)– ISPA is effective and thorough

Quantifying energy savings– Requires competent engineering– May warrant energy audit– May consider energy savings performance contract (ESPC)

Prioritize Saving Opportunities

Multiple filters– Financial return on investment

• Rank versus other energy saving opportunities• Rank versus other requests for capital• Risk

– Consistent with other priorities– Available and knowledgeable staff to manage project

Implement Savings Opportunities

Management commitment Operator and maintenance education and buy in

3. Measurement and Benchmarking

Sustaining energy efficiency efforts requires that effectiveness of past efforts be accurately evaluated. – Verify the performance of past energy-efficiency efforts– Inform the selection of future energy-efficiency initiatives– Help develop energy-efficiency targets

Measurement – Extend LEA with sliding NAC and EI to measure energy

efficiency improvement Benchmarking

– Compare NAC and EI for inter-facility benchmarking

Normalized Energy Intensity

1) Characterize performance with ‘Energy signature’ model

2) Remove noise with ‘Normalized annual consumption’ NAC

3) Track performance with ‘Sliding NAC’ analysis

4) Benchmark performance with ‘Multi-site sliding NAC’ analysis

Raw Energy and Production Data

Normalized Energy Intensity

Benchmark NEI vs. Multiple Facilities

Smallest Energy Users

Biggest Energy Decrease

Biggest Energy Increase

Biggest Energy Users

DNEI

NEI

Case Study: Turn off Make-up Air Units During Non-Production Hours

Baseline Post-retrofit

Heating Slope Decreases by 50%

Sliding NEI

Fuel NEI decreased by 23%

Independent of weather/production changes

Summary: Effective Energy Management

Develop baseline– Plant energy balance– Lean energy analysis (LEA)

Take action – Identify and quantify energy saving opportunities– Prioritize energy saving opportunities– Implement energy saving opportunities

Measure and benchmark to sustain efforts– Develop metrics for system energy efficiency– Measure energy efficiency improvement with sliding NAC and EI– Compare energy efficiency between facilities with NAC and EI