Materials & Equipment
Motors, process equipment, lighting, HVAC, charging equipment, and auxiliary power loads establish the connected equipment list.
Tools
BESS Scenario Modeler
Determine project value over time based on capacity and conditions.
Illustrative ScenarioConstant USDPre-TaxUnlevered
Project Net Present Value
$52.1 M Positive NPV
Current Scenario
Cumulative Discounted Cash FlowYear 15 $52.1M
Discounted Break-Even 7.8 years
Levelized Cost of Storage
$139.4 /MWh
Simple Payback
5.3 Years
Initial CapEx
$102.0 M
Annual Operating Cost
$7.0 M
Year 1Delivered Energy
400 MWh100 MW · 4 h
200 MW
0 h8 h
How to Read the BESS Scenario
Change power, duration, cost, operating assumptions or augmentation and review discounted cash flow, NPV, LCOS and payback on the same basis. The existing lifecycle and augmentation controls are included in preview access.
Review the Storage Estimating ProcessEstimate Class Calc
Let the missing definition set the class.
Set each deliverable to No, Prelim or Yes (complete). Every requirement for a class must be met; a completed drawing cannot offset a missing investigation.
18 preview deliverables. Professional Access adds 4 remaining deliverable checks.
Model Basis & Assumptions
The deliverable gates are an illustrative solar and storage adaptation. Complexity selects a position within the reference range for a class; it does not change the deliverable requirements.
AACE RP 18R-97 addresses process industries. Classification follows deliverable maturity, while project-specific accuracy requires risk analysis. See RP 18R-97 and AACE’s classification guide.
PV+Storage Sizer
Compare two routes from solar to storage.
Run the same PV array, POI limit and battery through AC and DC coupling. The model prioritizes clipped solar, then fills from available PV for evening discharge.
Annual Energy Delivered
265.2GWh
DC coupling · synthetic annual profileClipped Energy Recovered
14.2GWh
100% of PV-alone clippingBlended Cost of Energy
$80.1/MWh
PV alone: $65.0/MWhYear 1 Value vs. PV Alone
$7.2M
Energy and capacity value, before capital costSolar & Storage Dispatch
MW12:00PV Potential: 125.7 MWGrid Export: 96.3 MWBattery Charge¹: 29.4 MWBattery Discharge: 0.0 MW
Dotted reference: POI limit. ¹Charge is shown as AC-equivalent source power.
Annual Energy Waterfall
PV Potential271.7 GWh
Remaining Curtailment0.0 GWh
Storage Conversion Losses−6.5 GWh
Delivered to Grid265.2 GWh
Where Clipping Occurs
- At PV Inverters
- 5.7 GWh
- At the POI
- 8.5 GWh
- Total Before Storage
- 14.2 GWh
- Accessible to DC Storage
- 14.2 GWh
AC storage can recover POI clipping. DC storage can also reach energy clipped at the inverter, subject to battery power and energy limits.
| Annual and Installed Measures | AC Coupled | DC Coupled |
|---|---|---|
| Energy Delivered | 257.2 GWh | 265.2 GWh |
| Clipping Recovered | 8.5 GWh | 14.2 GWh |
| Storage Conversion Losses | 8.8 GWh | 6.5 GWh |
| Installed Capital Cost | $206.8M | $204.0M |
| Blended Cost of Energy | $83.6/MWh | $80.1/MWh |
| Year 1 Energy & Capacity Value | $18.2M | $18.5M |
| Value Less Annualized Cost | −$2.4M/yr | −$1.8M/yr |
Unlock site and efficiency calibration, detailed cost and value inputs, representative-day selection and sizing curves.
Model Basis & Assumptions
Annual results weight 36 synthetic days: 12 months × clear, partly cloudy and overcast conditions, each at 15-minute resolution. The solar resource scales a generalized profile; no location-specific weather data is loaded. Daily storage operation returns to its initial state of charge.
The battery captures clipping first and can top up from PV before evening discharge. It does not charge from the grid or optimize prices. Cost of energy uses discounted capital, O&M and modeled delivery over the selected life, with PV degradation. Taxes, incentives, financing, battery replacement and augmentation are excluded here. Cost and value inputs are illustrative calibration assumptions from the supplied example.
For architecture context, see the NREL/NLR PV-plus-battery technology baseline. This tool does not reproduce that model or its cost data.
Interconnection Cost Study
Connect the facilities, cost and schedule.
Build a screening ROM for the project substation, Gen-Tie, utility POI and network upgrades. Study maturity changes the cost bands and the remaining schedule.
138 kV
MWac
mi
Likely Interconnection Cost
$32.9M
$22.2M–$49.5M screening bandCost per Plant Capacity
$219/kW
150 MWac at 138 kVLikely Energization
55months
43–73 months, low to highCritical Path
Transformer
Main Transformer Supply & SetNetwork Upgrade Allowance
$7.5M
23% of likely interconnection costMain Transformer Lead Time
130weeks
Approximately 30 monthsCost Bands by Facility
Network upgrades remain an allowance until utility scope is defined.
| Facility | Low | Likely | High |
|---|---|---|---|
| Project Substation | $8.6M | $10.8M | $14.0M |
| Gen-Tie | $4.1M | $5.1M | $6.6M |
| Utility POI Facilities | $7.6M | $9.5M | $12.4M |
| Network Upgrades | $1.9M | $7.5M | $16.5M |
Schedule to Energization
Months from Now
012243648607284
Interconnection Studies
18
Engineering & Permitting
28
Substation & Gen-Tie Build
38
Transformer Supply & Set
52
Utility POI Facilities
38
Testing & Energization
55
Accent bars: likely critical path.
Pale extensions: high-case finish.
Workstreams run in parallel after the study / agreement milestone.
| Transformer Rating Basis | 157.9 MVA at 0.95 power factor; 1 unit at ≤200 MVA each |
|---|---|
| MV Feeders | 5 feeders at 30 MW per feeder |
| Gen-Tie Basis | 3 mi · single circuit · flat terrain |
| Study Maturity | System Impact Study; facility band -20% / +30% |
| Transformer Supply | 130 weeks + 2 months to set; order 2 months after agreement |
| Network Upgrades | $50/kW likely allowance; utility-determined scope may differ |
| Escalation | 0% · constant screening dollars |
Unlock unit-rate and lead-time calibration, early transformer procurement, voltage-distance sensitivity and a copyable ROM summary.
Model Basis & Assumptions
Unit rates and phase factors are screening ballparks retained from the supplied example, not independently verified market benchmarks. Base rates: $1.7M/mi Gen-Tie and $24/kVA main transformer at 138 kV, before outlook and escalation factors.
The project substation includes transformer supply and a balance-of-substation allowance. POI scope includes a station arrangement factor and remote-end allowance. Network upgrades are a separate allowance, not a load-flow or utility facilities study. Route acquisitions, financing, tax and project-specific utility conditions are not modeled.
Schedule branches run in parallel after the study / agreement milestone. Energization follows the latest branch plus commissioning. Early ordering moves transformer procurement up to 12 months ahead of agreement and introduces commitment risk; it does not accelerate studies, site permitting or utility construction.
System Fundamentals
PV Sizing & Output
Photovoltaic Output Calc
Connect DC and AC ratings to whole equipment quantities, then trace available power to the point of interconnection.
Installed DC Capacity
100.00MWdc
Whole module quantityInstalled AC Capacity
79.20MWac
Whole inverter blocksActual DC/AC Ratio
1.263×
After equipment roundingModeled POI Output
75.00MWac
Selected operating conditionEquipment Quantities
- PV Modules
- 160,000
- AC Blocks
- 18
- Strings
- Not Grouped
- Target AC Before Block Rounding
- 76.923 MWac
- AC Added by Block Rounding
- 2.277 MWac
- DC Added by Quantity Rounding
- 0.00 kWdc
Operating Power to the POI
1,000 W/m² · 45 °C cell
Current Output Limit POI Export Limit
Model Basis & Assumptions
DC Array Capacity is the requested front-side STC nameplate rating. Module quantities round upward, optionally to whole strings, to establish installed DC capacity. The target AC capacity is installed DC divided by the target DC/AC ratio. Identical AC blocks then round upward to meet that target; the actual ratio uses the installed quantities.
Available DC power = installed DC × plane-of-array irradiance ÷ 1,000 × [1 + temperature coefficient ÷ 100 × (cell temperature − 25)]. DC collection loss and constant inverter efficiency apply before the inverter AC rating caps output. AC collection and transformer loss applies next, followed by the POI export limit. The AC block input is an active-power rating in MWac.
This is an instantaneous operating scenario with user-defined irradiance, cell temperature, and loss assumptions. The illustrative defaults represent warm modules. A weather-based annual energy forecast, voltage and current string checks, and reactive-power or inverter temperature derating require additional modeling.
See PVWatts sizing and operating assumptions and SAM electrical loss boundaries for background.
Installed DC 100.000 megawatts. Installed AC 79.200 megawatts.160,000 modules and 18 AC blocks. Actual DC/AC ratio 1.263. Modeled POI output 75.000 megawatts.
System Fundamentals
Electrical Scope Explorer
An equipment schedule is only a starting point. Connections and installation conditions must be defined before applying assemblies or a cost basis.
Expand a topic to see typical equipment, installation roles, and scope interfaces.
1. System
What is connected?
Loads
Work & People
The owner and equipment suppliers define operating needs; the electrical designer develops the load basis and the installer connects the equipment.
Scope Boundary
Distinguish equipment supply from its feeder, disconnect, control wiring, and final connection. Confirm which loads operate together.
Voltage
Materials & Equipment
Service and distribution voltage affect transformers, switchgear, cable insulation, terminations, and equipment compatibility.
Work & People
The utility and electrical designer establish the voltage basis. Qualified installers and testing specialists work to the selected equipment requirements.
Scope Boundary
Identify the utility delivery voltage, project distribution voltage, and each transformation point. Keep utility-owned and project-owned equipment distinct.
Equipment Ratings
Materials & Equipment
Switchboards, transformers, breakers, inverters, and PCS units have capacity and duty ratings that drive equipment selection and counts.
Work & People
Designers specify the required duty; manufacturers provide rated assemblies. Installation crews set and connect them, with rigging support where required.
Scope Boundary
Separate nominal capacity from installed equipment capacity and the permitted operating limit. Include accessories and connections outside the vendor package.
Distribution Arrangement
Materials & Equipment
Radial or loop feeders, buses, duct banks, panels, and switching devices establish how power reaches each load or generation block.
Work & People
The designer defines the arrangement. Electrical crews install the feeders and equipment; the owner or utility operates the completed system within its boundary.
Scope Boundary
Trace every feeder from source to destination. Identify spare ways, future provisions, temporary distribution, and interfaces with existing systems.
Protection
Materials & Equipment
Breakers, fuses, relays, instrument transformers, and associated wiring support the protection scheme.
Work & People
Protection engineers establish coordination and settings. Relay technicians and testing specialists verify the installed system with the owner and utility.
Scope Boundary
Confirm who provides studies, settings, devices, testing, and utility acceptance. A supplied breaker does not automatically include all protection work.
Controls
Materials & Equipment
Controllers, PLC or RTU panels, EMS, SCADA interfaces, sensors, fiber, network equipment, and control power connect operational systems.
Work & People
Controls integrators and equipment vendors configure the interfaces; electrical and communications crews install the physical connections. Operations staff use the completed controls.
Scope Boundary
Define hardware, communications, programming, licenses, telemetry, cybersecurity requirements, and integration testing separately.
2. Installation
How is it connected?
Route Lengths
Materials & Equipment
Cable, conduit, trench, duct bank, pull structures, and restoration quantities depend on the installed route and transitions.
Work & People
Survey and design teams establish routes; civil and electrical crews execute the excavation, pathway, and cable work with equipment operators.
Scope Boundary
Account for vertical rises, equipment approach, bends, crossings, and termination allowances. Identify who excavates, backfills, and restores each route.
Raceway & Cable Assemblies
Materials & Equipment
Conduit, fittings, conductors, cable tray, splice kits, warning tape, and pull structures form complete installation assemblies.
Work & People
Electrical crews assemble pathways, pull cable, and make connections; civil crews and operators support underground installation where included.
Scope Boundary
State direct burial versus raceway, installation method, circuit basis, and included fittings. Keep material supply and installation responsibility explicit.
Supports
Materials & Equipment
Strut, brackets, hangers, tray supports, embedded items, anchors, and equipment foundations transfer installation loads to the structure or ground.
Work & People
Structural and electrical designers coordinate the support basis. Concrete, steel, and electrical crews install their respective portions.
Scope Boundary
Identify structural design, embeds, foundations, supports, seismic provisions where applicable, and field attachment responsibility.
Grounding
Materials & Equipment
Ground grids, bare conductors, rods, connectors, bonding jumpers, test points, and equipment bonds make up the installed grounding system.
Work & People
The designer defines the grounding basis. Electrical crews install and bond the system; qualified testing specialists verify the specified performance.
Scope Boundary
Separate the site grid, equipment bonds, lightning-related scope, and testing. Coordinate vendor, building, and utility interfaces.
Terminations
Materials & Equipment
Lugs, glands, stress-control kits, separable connectors, splice components, labels, and enclosure entries complete the ends of cable runs.
Work & People
Electrical crews and qualified cable jointers prepare connections; testing specialists verify the completed circuits as specified.
Scope Boundary
Count both ends, splices, and equipment interfaces. Confirm connector compatibility, vendor-supplied kits, specialty labor, and associated testing.
3. Conditions
How can it be built?
Access
Materials & Equipment
Temporary roads, mats, laydown, lifting equipment, delivery staging, and equipment transport may be needed before installation can start.
Work & People
Construction management coordinates logistics with civil crews, delivery teams, riggers, and equipment operators.
Scope Boundary
Assign road preparation, unloading, storage, final placement, access maintenance, and restoration. Confirm delivery and lifting limits.
Working Height
Materials & Equipment
Lifts, scaffolds, fall-protection provisions, elevated supports, and material handling equipment change the installation method.
Work & People
Installation crews use the required access equipment; trained operators and site supervision coordinate its use and availability.
Scope Boundary
Identify who furnishes access equipment, setup and relocation time, shared use, and restrictions around other work.
Site Conditions
Materials & Equipment
Rock excavation, dewatering, unsuitable soils, corrosion protection, stabilization, weather protection, and restoration can add scope.
Work & People
Geotechnical and design teams establish the basis. Civil crews, operators, and specialty subcontractors address the defined conditions.
Scope Boundary
Record assumed ground conditions, investigation coverage, exclusions, allowances, and responsibility for changed conditions.
Outages
Materials & Equipment
Temporary distribution, bypass equipment, replacement components, and shutdown support may be required to complete an interface.
Work & People
The owner or utility controls the operating window. Authorized operations staff, qualified electrical crews, and testing teams coordinate the planned work.
Scope Boundary
Define the permitted window, temporary service, switching responsibility, advance approvals, and return-to-service acceptance.
Phasing
Materials & Equipment
Temporary feeds, staged deliveries, partial systems, repeated mobilizations, and protection of completed work affect the scope.
Work & People
Project controls, construction management, trade foremen, and owner representatives coordinate the sequence and handoffs.
Scope Boundary
Distinguish one continuous installation from multiple phases. Identify temporary work, remobilization, partial turnover, and trade interfaces.
Testing
Materials & Equipment
Test equipment, temporary power, instrumentation, consumables, and documentation support specified verification and commissioning.
Work & People
Testing specialists, relay technicians, vendors, and commissioning teams perform the defined checks; the owner or utility may witness acceptance.
Scope Boundary
Identify factory versus field tests, pre-energization work, integration and performance tests, witnessing, retesting, and included vendor support.
Turnover
Materials & Equipment
Labels, record drawings, operating manuals, spare parts, training materials, and closeout records complete the handover package.
Work & People
The contractor, designers, vendors, and commissioning team assemble deliverables. Owner operations and maintenance staff receive the completed system.
Scope Boundary
Define documentation, training, spares, warranty start, punch-list completion, and the point when operational responsibility transfers.
These examples identify work packages and interfaces. Project drawings, specifications, supplier scope, and execution plans establish the actual quantities and responsibilities.
Professional Access
Unlock premium features to calibrate scenario models with more definition and finer basis control.
Free access only previews a limited basis of core scenario calculations and model inputs. Unlock access for extended controls below.
Premium Model
Advanced Estimate Class Calc
Remaining schedule, survey, labor and storage augmentation deliverables, plus target-class selection, contingency comparison and an exportable gap report.
Premium Model
Advanced PV+BESS Sizer
Site resource, efficiencies, capital and operating cost calibration, energy values, representative-day selection and storage sizing curves.
Premium Model
Advanced Interconnection Cost Study
Unit rates, labor factors, lead times, at-risk equipment procurement, voltage-drop matrix, and exportable summary.
Premium Model
Bid Leveling Dashboard
Normalize proposals, align inclusions and exclusions, and identify scope gaps.
Premium Model
Risk & Contingency Simulator
Connect cost ranges and risk events to probabilistic outcomes.
Premium Model
Project Calibration Library
Save project-specific unit rates, productivity assumptions and scenario versions.
Premium Model
Weather & Dispatch Imports
Use site-specific time series and richer dispatch constraints in the hybrid model.
Premium Model
BESS Sensitivity & Workbook Export
Compare scenario sweeps and export the basis and results for review.
Premium Model
Operations & Maintenance Planning
Assign O&M tasks and WBS categories with defined work breakdown structures and schedules.