What is capacity factor in a solar farm?

Capacity factor is actual annual energy output divided by theoretical maximum (nameplate capacity × 8,760 hours). For US utility-scale solar, capacity factors typically range 18-30% — desert Southwest (CA, AZ, NV) reaches 28-32% with single-axis tracking; New England + PNW run 14-18%. The metric is the most important operational input to LCOE and PPA pricing. Capacity factor degrades 0.5-0.8% per year as panels age; tracker downtime, soiling, and grid curtailment all reduce realized capacity factor below modeled.

What is a PPA in solar?

A Power Purchase Agreement (PPA) is a long-duration contract (typically 15-25 years) where the off-taker — utility, corporate buyer, community subscriber base — agrees to buy 100% of project output at a fixed $/MWh price (often with annual escalator). PPAs underpin project financeability: a creditworthy off-taker enables 70-80% non-recourse debt at low interest rates. Corporate PPAs (Google, Amazon, Meta, Microsoft) now drive ~40% of US solar deal flow, replacing IOU off-take in deregulated markets.

Which yieldcos and REITs invest in solar?

No traditional Equity REIT focuses on solar; the institutional vehicles are publicly listed renewable infrastructure yieldcos: Brookfield Renewable Partners (BEP, ~33 GW global), NextEra Energy Partners (NEP, NEE yieldco), Clearway Energy (CWEN, NRG yieldco), Atlantica Sustainable Infrastructure (AY, global), and Hannon Armstrong (HASI, mortgage REIT structure for climate finance). NextEra Energy (NEE) is the largest solar developer in the US with 25+ GW operating + contracted.

Solar Farm KPIs.

Solar Farms are utility-scale photovoltaic generation facilities — typically 5 MW to 500 MW — that sell electricity under long-duration Power Purchase Agreements (PPAs, 15-25 years) or via merchant exposure to wholesale power markets. Performance is measured in capacity factor (actual output ÷ nameplate × 8,760 hours, typically 18-30% in US locations), levelized cost of energy (LCOE), PPA price per MWh, panel degradation curve (0.5-0.8% per year), and EBITDA per MW. The economic structure layers Investment Tax Credit (ITC, 30% post-IRA), Production Tax Credit (PTC), accelerated MACRS depreciation, and tax-equity investor returns. Comparable yieldcos and renewable-infrastructure companies: BEP (Brookfield Renewable), NEP (NextEra Energy Partners), HASI (Hannon Armstrong), CWEN (Clearway Energy), and AY (Atlantica Sustainable Infrastructure). Ilora.ai ingests SCADA performance data, PPA terms, capacity-factor reports, panel degradation tracking, O&M cost flow, and tax-equity waterfall, then benchmarks each project against BEP, NEP, HASI, CWEN comparables. SEIA, NREL, and Wood Mackenzie Power & Renewables are the canonical industry references.

12 definitions · Sector: INFRASTRUCTURE · Used by Ilora.ai specialist AI agents

NOI: Total revenue minus operating expenses (excludes financing and capital costs). The primary measure of property-level profitability.
Cap Rate: Net Operating Income divided by current property value. Expresses unleveraged annual yield as a percentage.
DSCR: Net Operating Income divided by total annual debt service. Lender-required cushion measure; below 1.0 means NOI cannot cover debt.
LTV: Loan amount divided by property value. Lower LTV = lower lender risk.
OER: Operating expenses divided by gross revenue. Lower is better, but varies by property type (hotels run higher than triple-net retail).
GRM: Property value divided by gross annual rental income. Quick valuation shortcut; less precise than cap rate.
IRR: Annualized return on investment accounting for time value of money across the full hold period.
CoC: Pre-tax annual cash flow divided by total cash invested. Measures the cash yield, not total return.
DCF: Valuation method that projects future cash flows and discounts them to present value at a chosen rate.
TTM: A rolling sum of the most recent 12 months. Smooths seasonality for KPI comparisons.
Tenants: Number of carriers leasing on a single cell tower. Each additional tenant is high-margin incremental revenue.
CF: Actual energy generated divided by theoretical maximum. Solar farm productivity measure.

Sub-types

Sub-types within Solar Farm.

Utility-Scale Ground Mount: 20-500 MW single-site project on owned or leased land.
Community Solar: 1-5 MW project with retail subscribers receiving bill credits.
Commercial / Industrial Behind-the-Meter: On-site rooftop or carport offsetting host load.
Solar + Storage (Hybrid): PV combined with BESS for capacity firming + arbitrage.
Floating Solar (Floatovoltaics): Panels mounted on pontoons over water bodies; emerging in Asia + EU.

Amenities & features

7 amenities Ilora.ai tracks for Solar Farm.

Photovoltaic Panel Array: Crystalline silicon or thin-film panels — typically 350-700W per module. Drives nameplate capacity.
Panel efficiency (W/m²)
Annual degradation rate
Single-Axis Tracking System: Mechanical tracker rotating panels east-to-west during the day; +15-25% capacity factor vs fixed-tilt.
Tracker uptime
Tracker O&M cost
Inverters (Central or String): DC-to-AC conversion equipment; typically 95-99% efficient.
Inverter efficiency
Inverter MTBF
Substation + Grid Interconnect: Transformer + switchgear stepping output up to transmission voltage.
Interconnect capacity (MW)
Curtailment %
Battery Storage (Co-Located): Lithium-ion BESS — increasingly required for solar+storage PPAs.
Storage capacity (MWh)
Round-trip efficiency
Perimeter Fencing + Security: Security perimeter with cameras + remote monitoring.
Security cost per MW
Access Roads + Right-of-Way: Internal access roads for O&M crews + interconnect easements.
ROW cost per MW

Industry reference

How the solar farm sector operates.

Market segments

Investor-owned utility (IOU) PPA
Municipal utility / public power PPA
Corporate PPA (Google, Amazon, Meta, Microsoft)
Community solar subscribers
Merchant wholesale power
Behind-the-meter C&I
Federal / DoD off-take

Operating models

IPP (Independent Power Producer) own + operate
Tax-equity partnership (sponsor + tax-equity investor)
Yieldco / publicly listed renewable holding
BOOT (Build-Own-Operate-Transfer) to utility
Solar developer flip post-COD

Regulatory frameworks

FERC Order 2222 (DER aggregation)
NERC reliability standards
IRS ITC (30% post-IRA Section 48)
IRS PTC (Section 45)
IRA prevailing wage + apprenticeship (10% adder)
NEPA / state environmental review
PURPA qualifying facility status
State RPS (Renewable Portfolio Standards)

Industry organizations

SEIA (Solar Energy Industries Association)
NREL (National Renewable Energy Laboratory)
Wood Mackenzie Power & Renewables
BloombergNEF
EPRI (Electric Power Research Institute)
ACORE (American Council on Renewable Energy)

Comparable public REITs / operators

BEP (Brookfield Renewable Partners) — diversified renewable IPP
NEP (NextEra Energy Partners) — yieldco of NEE
HASI (Hannon Armstrong Sustainable Infrastructure Capital) — climate finance REIT
CWEN (Clearway Energy) — solar + wind yieldco
AY (Atlantica Sustainable Infrastructure) — global renewable yieldco
No traditional Equity REIT pure-play; SEIA tracks ~50 utility-scale solar developers

Documents Ilora.ai ingests

SCADA performance data (15-minute intervals)
PPA contract + pricing schedule
Capacity-factor monthly report
Panel degradation tracking report
O&M cost-flow ledger
Tax-equity waterfall + cash sweep
Interconnection agreement
Renewable Energy Certificate (REC) registry
Insurance binder (property + business interruption)
Land lease + ROW agreements

Industry tools (we integrate with these)

Power Factors (asset performance management)
AlsoEnergy PowerTrack (monitoring)
Scada-Trace
PVsyst (production modeling)
Helioscope (design + simulation)
Locus Energy (analytics)
Ezenza (O&M)
TigoEnergy (module-level optimization)
Athena Energy (PPA management)
GreenLake Solar (asset management)

Frequently asked

Common questions about solar farm.

What is capacity factor in a solar farm?: Capacity factor is actual annual energy output divided by theoretical maximum (nameplate capacity × 8,760 hours). For US utility-scale solar, capacity factors typically range 18-30% — desert Southwest (CA, AZ, NV) reaches 28-32% with single-axis tracking; New England + PNW run 14-18%. The metric is the most important operational input to LCOE and PPA pricing. Capacity factor degrades 0.5-0.8% per year as panels age; tracker downtime, soiling, and grid curtailment all reduce realized capacity factor below modeled.
What is a PPA in solar?: A Power Purchase Agreement (PPA) is a long-duration contract (typically 15-25 years) where the off-taker — utility, corporate buyer, community subscriber base — agrees to buy 100% of project output at a fixed $/MWh price (often with annual escalator). PPAs underpin project financeability: a creditworthy off-taker enables 70-80% non-recourse debt at low interest rates. Corporate PPAs (Google, Amazon, Meta, Microsoft) now drive ~40% of US solar deal flow, replacing IOU off-take in deregulated markets.
Which yieldcos and REITs invest in solar?: No traditional Equity REIT focuses on solar; the institutional vehicles are publicly listed renewable infrastructure yieldcos: Brookfield Renewable Partners (BEP, ~33 GW global), NextEra Energy Partners (NEP, NEE yieldco), Clearway Energy (CWEN, NRG yieldco), Atlantica Sustainable Infrastructure (AY, global), and Hannon Armstrong (HASI, mortgage REIT structure for climate finance). NextEra Energy (NEE) is the largest solar developer in the US with 25+ GW operating + contracted.

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