Study guide
2.4 Demand-Side Management, Load Curtailment, and Transportation Energy Efficiency
AEE Certified Energy Manager CEM
Track your progress as you read
Finished sections get a check mark.
1 Chapter 1: Energy and Sustainability Policies, Codes, and Standards
1.1 Federal and State Energy Policies, Decarbonization Targets, and ESG Reporting 1.2 Building Energy Codes: ASHRAE Standard 90.1, IECC, and Compliance Paths 1.3 Energy Management Systems: ISO 50001, ENERGY STAR Benchmarking, and Portfolio Manager
2 Chapter 2: Energy Rates, Tariffs, and Supply Options
2.1 Utility Rate Structures: Volumetric vs. Demand Charges, Time-of-Use (TOU), and Real-Time Pricing 2.2 Demand Charges, Ratchets, Peak Shaving, and Power Factor Penalties 2.3 Energy Procurement, Deregulated Markets, Supply Contracts, and Green Tariffs 2.4 Demand-Side Management, Load Curtailment, and Transportation Energy Efficiency
3 Chapter 3: Energy Audits and Instrumentation
3.1 Energy Audit Methodologies: ASHRAE Level I, II, and III Audit Scopes 3.2 Audit Instrumentation, Data Loggers, Metering Accuracy, and Safety (PPE) 3.3 Baseline Energy Data, Utility Bill Disaggregation, and ECM Identification 3.4 Energy Modeling, Simulation, Digital Tools, and Performance Indicators
4 Chapter 4: Energy Accounting and Economics
4.1 Energy & Power Units (kWh, kW, Therms, MMBtu, Joules) and Conversion Calculations 4.2 Financial Metrics: Simple Payback Period, Return on Investment (ROI), and LCCA 4.3 Time Value of Money: Net Present Value (NPV), Internal Rate of Return (IRR), and Escalation 4.4 Advanced Financial Evaluation: Annual Worth, SIR, Depreciation, and Interest Formulas
5 Chapter 5: Electrical Power Systems and Motors
5.1 Electrical Fundamentals: Single/Three-Phase Power, Apparent/Real/Reactive Power, and Power Factor 5.2 Electric Motors: Efficiency Classes, Loading Calculations, NEMA Premium, and Losses 5.3 Variable Frequency Drives (VFDs), Affinity Laws, and Electrical Harmonics
6 Chapter 6: Lighting Systems
6.1 Lighting Fundamentals: Photometric Quantities (Lumens, Lux, Foot-Candles, CRI, CCT) and Efficacy 6.2 Lighting Technologies & Retrofits: LED Systems, Fluorescent/HID Replacement, and LPD 6.3 Lighting Controls: Occupancy/Vacancy Sensors, Daylight Harvesting, Dimming, and Task Tuning
7 Chapter 7: HVAC Systems and Building Envelope
7.1 HVAC Fundamentals & Psychrometrics: Dry-Bulb, Wet-Bulb, Dew Point, Relative Humidity, and Enthalpy 7.2 Cooling and Heating Equipment: Chillers (COP, kW/ton, EER, SEER), Heat Pumps, and Boilers 7.3 Air and Water Distribution: AHUs, VAV vs. CAV, Pumping Systems, Fans, and Economizers 7.4 Building Envelope: Heat Transfer (U-factor, R-value, SHGC), Infiltration, and Thermal Insulation 7.5 Building Envelope Calculations: Degree-Days, Solar Heat Gain, and Passive Design 7.6 Refrigerants, Cooling Towers, and Specialized HVAC Technologies (Absorption, VRF, Chilled Beams)
8 Chapter 8: Building Automation, Controls, and Artificial Intelligence Systems
8.1 Building Automation Systems (BAS) Architecture, BACnet, Modbus, and DDC Loops 8.2 Energy Control Strategies: Temperature/Pressure Resets, Night Setback, and Deadbands 8.3 Fault Detection & Diagnostics (FDD), Energy Analytics, and AI Optimization 8.4 IoT, Cloud-Based BAS, Expert Systems, and Cyber-Security
9 Chapter 9: Energy Storage Systems
9.1 Battery Energy Storage Systems (BESS): Technologies, Capacity, Efficiency, and Safety 9.2 Thermal Energy Storage (TES): Chilled Water, Ice Storage, and Phase Change Materials 9.3 Storage Dispatch Strategies, Tariff Integration, Peak Shaving, and Microgrid Integration
10 Chapter 10: Boiler and Steam Systems
10.1 Boiler Fundamentals & Efficiency: Combustion Efficiency, Excess Air, and Stack Losses 10.2 Steam Distribution & Traps: Steam Trap Types, Failure Modes, Testing, and Insulation 10.3 Condensate Recovery, Boiler Blowdown Control, and Waste Heat Recovery
11 Chapter 11: Distributed Generation and Renewable Energy Systems
11.1 Solar Photovoltaic (PV) and Wind Energy Systems: Design, Inverters, and Capacity Factor 11.2 Combined Heat and Power (CHP) / Cogeneration: Thermal Efficiency and System Sizing 11.3 Grid Interconnection, Net Metering, Islanding, and Microgrid Resilience 11.4 Biomass, Geothermal, Hydropower, Solar Thermal, and Waste-to-Energy Systems
12 Chapter 12: Industrial Systems
12.1 Compressed Air Systems: Efficiency, Pressure Drop, Leak Management, and Receiver Storage 12.2 Industrial Process Heating, Cooling Towers, and Industrial Refrigeration 12.3 Production-Normalized Energy Metrics, Pumping System Optimization, and Process Integration
13 Chapter 13: Operations, Maintenance, and Commissioning
13.1 Preventive, Predictive, and Reliability-Centered Maintenance Strategies 13.2 Building Commissioning: Existing Building Commissioning (EBCx) & Retro-Commissioning (RCx) 13.3 Savings Persistence, Continuous Commissioning, Sensor Calibration, and Alarms 13.4 Quantifying O&M Losses: Compressed Air Leaks, Steam Traps, Boiler Scale, and Group Relamping 13.5 CMMS, Water Treatment, and Human Behavior in Energy Management
14 Chapter 14: Energy Savings Performance Contracting and Measurement & Verification
14.1 Energy Savings Performance Contracting (ESPC), ESCO Roles, and Financing Models 14.2 Measurement and Verification (M&V): IPMVP Options A, B, C, and D 14.3 Baselines, Weather Normalization, Non-Routine Adjustments, and M&V Reporting
2.4 Demand-Side Management, Load Curtailment, and Transportation Energy Efficiency
Key Takeaways Explain This Topic AI
Demand-Side Management (DSM) encompasses utility- or customer-driven programs that change the timing or magnitude of energy use, split into energy efficiency (reducing total consumption) and load management (shifting or curtailing peak demand).
Demand response (DR) programs are either price-responsive (time-of-use, real-time, critical-peak pricing) or incentive-based (interruptible load, direct load control, capacity bidding), and a CEM quantifies curtailment revenue against penalty risk before enrolling a facility.
Primary power is firm capacity dispatched from a utility's base-load generation, while secondary power is lower-cost, non-firm economy energy purchased from the spot or short-term market; blending primary and secondary supply is a core procurement tactic for reducing average price.
Transportation energy efficiency—fleet right-sizing, anti-idling, EV adoption, and electrification—now falls within the CEM scope because vehicle charging adds a controllable, often shiftable load to the facility demand profile.
A load factor below ~0.40 signals a peaky profile that wastes demand charges; DSM and DR are the primary tools a CEM uses to raise load factor and cut the billed demand ratchet.
Last updated: July 2026
Demand-Side Management, Load Curtailment, and Transportation Energy Efficiency
A Certified Energy Manager (CEM) is rarely satisfied with simply buying energy at the posted tariff. The demand side of the meter—how, when, and how much energy is consumed—is where the largest controllable savings often hide. Demand-Side Management (DSM) is the umbrella term for the planning, implementing, and monitoring of activities designed to influence customer use of energy. The CEM Body of Knowledge places DSM, primary/secondary power selection, and transportation efficiency within the Rates, Tariffs, and Supply Options domain because each directly changes what a facility pays and when it pays it.
The Two Branches of DSM
DSM programs divide into two complementary branches:
Branch Goal Typical Tactics
Energy Efficiency Reduce total energy consumed (kWh, therms) High-efficiency equipment, LED retrofits, VFDs, envelope upgrades
Load Management Change the timing or peak magnitude of demand (kW) Peak shaving, load shifting, demand response, thermal storage, scheduling
Energy efficiency lowers the area under the load curve; load management reshapes the curve. A facility that cuts kWh but holds its peak flat will still pay heavy demand charges—a frequent blind spot the CEM must expose.
Demand Response and Load Curtailment
Demand Response (DR) is a subset of load management in which a customer voluntarily reduces consumption during grid-stressed or high-price periods in exchange for payment or rate relief. DR programs fall into two families:
Price-responsive DR: customers react to price signals— time-of-use (TOU) , real-time pricing (RTP) , and critical-peak pricing (CPP) . The customer decides how much to curtail based on economics.
Incentive-based DR: customers commit to a contractual curtailment level for a payment— interruptible load tariffs, direct load control (utility cycles off AC or water heaters), capacity bidding programs, and reserve/ancillary-services markets.
Before enrolling a facility, the CEM quantifies the trade-off: curtailment payments versus the cost of the curtailment action (startup/shutdown losses, lost production, thermal discomfort, and any penalty for under-performance). The interruptible load tariff offers a steep demand-charge discount in exchange for the utility's right to interrupt service on short notice; the CEM must confirm the facility can actually shed the agreed kW when called or face hefty penalties.
Load Factor as the Diagnostic
Load factor = average demand ÷ peak demand over the billing period. A load factor below ~0.40 indicates a peaky profile that wastes demand charges. DSM and DR are the principal tools for raising load factor—shifting discretionary load (charging, pumping, batch processes) into off-peak hours flattens the curve and shrinks the billed demand ratchet.
Primary and Secondary Power
Utilities and large buyers distinguish two supply tiers:
Primary power is firm capacity dispatched from base-load plants (coal, nuclear, combined-cycle gas, hydro). It is reliable and priced into the standard tariff or a long-term contract.
Secondary power is non-firm, lower-cost economy energy bought from the spot, day-ahead, or short-term market. It is curtailment-prone but cheap.
A sophisticated CEM blends the two: size primary capacity to the firm minimum and buy secondary (economy) energy for discretionary, deferrable loads. This primary/secondary supply strategy lowers the average price per kWh without exposing critical loads to interruption. The decision mirrors the demand-side choice: firm capacity costs more but is always available.
Energy Efficiency in Transportation
The CEM Body of Knowledge explicitly includes Energy Efficiency in Transportation . Once outside the facility fence, transportation is now firmly inside energy management for three reasons:
Corporate fleets are a measurable, often large energy spend (diesel, gasoline, and now electricity).
Electrification moves vehicle energy from liquid fuels to the electric meter, directly altering a facility's load profile.
EV charging load is discretionary in time—a prime DR and load-shifting resource.
Key tactics a CEM applies to transportation:
Fleet right-sizing and anti-idling: matching vehicle class to duty cycle and cutting idle time, the cheapest diesel/gallon saved.
Fuel-economy and CAFE awareness: selecting vehicles against Corporate Average Fuel Economy thresholds and lifecycle fuel cost.
EV adoption and managed charging: converting fleet miles to electricity; sizing chargers; scheduling charging into off-peak/TOU valleys to avoid a new demand peak.
Electrification impact analysis: quantifying the added electrical load (kW and kWh) and confirming the service entrance and tariff can absorb it without a costly upgrade or a ratchet trip.
Worked Example: EV Charging Demand Impact
A facility adds 20 Level-2 chargers at 7.2 kW each. Uncontrolled simultaneous charging adds 144 kW to peak demand. At a demand charge of $15/kW-month, that is $2,160/month in new demand cost—roughly $25,920/year—before a single kWh is billed. With managed charging (staggered starts and a 40% diversity factor), peak adds only ~58 kW, cutting the demand bill by ~60%. The CEM's job is to capture the fuel savings and avoid the demand trap.
Connecting DSM to the Tariff
DSM is never evaluated in isolation—it must be mapped to the specific tariff in force. A demand charge of $18/kW with a 12-month ratchet rewards peak shaving far more than energy reduction; an energy-only RTP tariff rewards load shifting into negative-price hours. The CEM's DSM strategy is therefore tariff-shaped: pick the curtailment, storage, or electrification move that attacks the largest dollar line on the bill.