01
Right location
Participating customers and resources must be electrically relevant to the constrained transformer, lateral, feeder or substation area.
Non-Wires Alternatives Modeling
Test flexible-load strategies before committing to conventional grid upgrades.
GIM evaluates whether managed EV charging, DSM, DER, home batteries and VPP resources can reduce the specific local and system-peak loads driving a planning need.
Localized 8,760 load forecasts · Customer and block-group targeting · Participation, dispatch and rebound scenarios
What an NWA must prove
Generic energy savings are not enough
A credible non-wires alternative must address the actual grid need—not simply reduce annual kWh or produce savings somewhere else on the system.
02
Right hours
Load reduction must occur during the hours and seasons when the asset or system is expected to reach its planning threshold.
03
Enough dependable kW
The portfolio must deliver sufficient reduction after participation, availability, control effectiveness and operational limits are considered.
04
Required duration
Resources must sustain performance across the complete constraint window rather than provide a short response that ends too soon.
05
Manageable rebound
Deferred charging, preheating, precooling and other recovery loads cannot simply create a new peak immediately afterward.
06
Competitive cost and risk
Program acquisition, incentives, technology and operating risks must compare favorably with the upgrade or other feasible alternatives.
GIM non-wires screening workflow
Match flexible resources to the forecast grid need
The analysis begins with the load and location creating the exposure, then builds a resource portfolio around that need.
Define the need
Identify the location, forecast year, peak hours, magnitude, duration and planning threshold.
Build the baseline
Forecast customer-level 8,760 loads with EVs, electrification, growth and weather.
Select resources
Choose managed charging, DSM, DER, batteries or a combined VPP portfolio.
Simulate dispatch
Apply participation, availability, event timing, duration, control and recovery assumptions.
Compare outcomes
Measure residual exposure, system benefits, implementation requirements and next steps.
Flexible-load and distributed resources
Evaluate individual programs or a coordinated portfolio
GIM represents end-use load shapes, customer characteristics and dispatch timing so resources can be evaluated against local and coincident peaks rather than as annual-average savings.
EV
Managed EV charging
Shift charging away from constrained or G&T coincident-peak hours while preserving required vehicle energy.
- Time-of-use response
- Direct managed charging
- Availability and engagement
AC
Air conditioning
Model targeted cooling strategies around summer peaks and weather-sensitive local loads.
- Precooling
- Direct load control
- Thermostat adjustments
HEAT
Space heating
Evaluate winter demand reduction with attention to temperature, comfort and post-event recovery.
- Preheating
- Direct load control
- Thermostat strategies
WH
Water heating
Use thermal storage and control flexibility to reduce peak-hour contribution.
- Direct load control
- Temperature strategies
- Recovery-load timing
DER
DER and storage
Test customer-side generation and storage dispatch during local or service-area peak periods.
- Home batteries
- EV batteries
- Distributed resources
VPP
Virtual power plants
Combine different customer resources and dispatch rules into a coordinated portfolio.
- Resource availability
- Portfolio participation
- Local and system objectives
Hour-specific scenario modeling
Model performance—not nameplate potential
The relevant value is the kW that can actually be delivered during the constraint window after real-world program and operating limits are applied.
Parameters that determine dependable impact
Utility users can revise key program design assumptions and compare conservative, expected and higher-performance cases.
Eligible customersProgram participationResource availabilityControl effectivenessEvent start timeEvent durationDispatch frequencyRecovery and reboundCustomer comfort limitsTargeted geography
ResourceTypical actionCritical modeling issue
Managed EV chargingShift / staggerVehicle availability and deferred energy
Air conditioningPrecool / controlWeather, comfort and rebound
Water heatingInterrupt / resetThermal storage and recovery
Home batteryDischargeState of charge and event duration
VPP portfolioCoordinateAvailability across multiple resources
Screening limitation: GIM estimates hourly load-shape and program impacts for planning and prioritization. It does not replace feeder power flow, voltage, thermal, protection, communications, interconnection, cybersecurity, customer-acquisition or detailed implementation studies.
Compare alternatives consistently
Screen the NWA against the conventional solution
A lower-cost program is not automatically a viable substitute for an upgrade. The comparison must account for timing, reliability, lead time, useful life, operational complexity and residual risk.
GIM supplies the localized hourly load and customer-side resource analysis. Utilities can combine those results with their engineering estimate of the conventional project and current program or vendor costs.
Where screening creates value
Use NWA analysis to improve—not delay—utility decisions
The purpose is to identify credible candidates early and reject weak ones before substantial engineering, procurement or program-development resources are committed.
01
Target the right customers
Use customer and block-group characteristics to locate eligible resources within the area creating the planning need.
02
Reveal timing mismatches
Identify programs that reduce energy or system peak but fail to address the actual local constraint hours.
03
Test portfolio combinations
Combine EVs, HVAC, water heating and storage when one resource alone cannot supply enough dependable reduction.
04
Coordinate local and system value
Find strategies that address local exposure while also reducing G&T demand charges or service-area peaks.
05
Prioritize detailed studies
Direct engineering, vendor engagement and customer research toward locations and portfolios with the strongest initial case.
06
Manage forecast uncertainty
Compare adoption, participation, weather and growth scenarios before locking into one assumed future.
Proper role of the Grid Impact Model
What GIM does—and what must follow
GIM supports
- Localized baseline and future 8,760 load forecasts
- Customer and geographic resource targeting
- Managed charging, DSM, DER, battery and VPP scenarios
- Participation, dispatch, duration and recovery sensitivity analysis
- Comparison of residual local and system peak loads
- Screening and prioritization of NWA candidates
GIM does not replace
- Asset-specific field measurements and condition assessment
- Power-flow, voltage, thermal and protection analysis
- Interconnection and communications engineering
- Vendor procurement and binding cost proposals
- Customer recruitment or performance demonstrations
- Final determination that an infrastructure project can be deferred
Frequently asked questions
Non-wires alternatives and GIM
What is a non-wires alternative?
A non-wires alternative uses demand-side or distributed resources to defer, reduce, complement or potentially avoid a conventional transformer, feeder or substation investment.
When is an NWA most promising?
The strongest candidates usually have a clearly defined need, sufficient lead time, a limited number of critical hours, an electrically relevant customer base and flexible resources that can be acquired reliably at a competitive cost.
How can managed EV charging help?
Managed charging can stagger or shift charging away from constrained local hours and G&T coincident peaks. Its value depends on EV location, enrollment, vehicle availability, control effectiveness and the amount of energy that must be recovered later.
Can GIM model several resources together?
Yes. Managed charging, space conditioning, water heating, appliances, DER and storage scenarios can be evaluated individually or in coordinated combinations.
Does a favorable screen mean an upgrade can be canceled?
No. It means the candidate merits detailed engineering, cost, implementation and performance evaluation. Final deferral requires much stronger evidence than a planning-level model screen.
How does this connect to the managed-charging business case?
The NWA analysis evaluates hourly and localized load relief. The GIM managed-charging business case separately quantifies G&T demand savings, program costs, revenue margins, payback, benefit-cost ratio and NPV.
Identify which flexible-load strategies merit a closer look.
Request a guided demonstration of localized loads, program dispatch, residual grid exposure and NWA screening scenarios.