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JUSTSOLAR — Solar Module Manufacturer

Solar Project Financing Guide
CAPEX · PPA · Lease · PACE · Bonds (2026)

The B2B playbook: how corporate developers, EPCs, and commercial buyers structure solar project financing. 5 financing models compared, IRR/NPV/LCOE benchmarks, and how module sourcing affects project economics.

5 Financing Structures Compared

Each with pros, cons, typical IRR, and minimum project size.

CAPEX (Self-Financed)

Best for

Corporate buyer with strong balance sheet, wanting 100% asset ownership & full savings

IRR: 15-25%Payback: 4-7Min: No minimum
How it works

Customer pays upfront CAPEX (typically $0.50-1.20/Wp turnkey). Full tax depreciation + all savings to customer.

Pros

Highest IRR (15-25% unlevered), no long-term contracts, full ownership, instant balance-sheet asset.

Cons

Large upfront cash outlay; opportunity cost of capital.

PPA (Power Purchase Agreement)

Best for

C&I buyer wanting no CAPEX, stable electricity cost, off-balance-sheet

IRR: N/A (tariff-based)Payback: Immediate savingsMin: Usually 500 kWp+
How it works

Developer owns + operates system on customer's site. Customer buys solar kWh at agreed $/kWh (typically 10-30% below grid). Contract 15-25 years.

Pros

Zero CAPEX, instant savings day 1, O&M handled by developer, off-balance-sheet.

Cons

Lower lifetime savings vs CAPEX, long-term lock-in, complex contract, transfer risk on property sale.

Solar Lease

Best for

Commercial/municipal buyer wanting predictable fixed monthly payment

IRR: N/APayback: Monthly savings vs lease paymentMin: 100 kWp+
How it works

Customer leases equipment; fixed monthly payment (5-25 years). Own system at end (EBO) or buyout/renewal option.

Pros

Predictable cost, no CAPEX, simpler than PPA structure, may qualify for tax advantages.

Cons

Tax credits sometimes captured by lessor not lessee; total cost higher than CAPEX.

PACE Financing (USA)

Best for

US commercial property owners with long hold period

IRR: N/APayback: Depends on rateMin: 200 kWp+
How it works

Loan attached to property tax bill, 10-30 year term. Transfers with property sale. Available in C-PACE-enabled states.

Pros

Long tenor, transfers with property, 100% financing possible, off-balance-sheet.

Cons

USA-only (C-PACE), subject to state/local adoption, mortgage lender consent required.

Green Bonds / Project Finance

Best for

Utility-scale 20+ MW projects, developer with track record

IRR: Equity IRR 10-18% typicalPayback: 10-15 (debt); 7-10 equityMin: 20 MW+
How it works

Non-recourse project finance. 70-80% debt, 20-30% sponsor equity. Debt tenor 15-22 years. Requires BNEF Tier-1 module, bankable EPC, offtaker PPA.

Pros

Capital-efficient, scalable to hundreds of MW, developer retains control.

Cons

Bankability requirements exclude smaller/newer developers; long due-diligence cycle.

Financial Metrics Cheat Sheet

LCOELevelized Cost of Energy
Formula

Σ(CAPEX + OPEX_t) / Σ(Energy_t) ÷ discount factor

2026 Benchmark

$20-45/MWh utility; $50-90/MWh C&I rooftop (2026)

IRRInternal Rate of Return
Formula

Rate where NPV = 0

2026 Benchmark

15-25% unlevered CAPEX; 10-18% levered project finance

NPVNet Present Value
Formula

Σ Cash Flow_t / (1+r)^t − CAPEX

2026 Benchmark

Positive NPV @ 8-10% discount rate = go decision

PaybackSimple Payback Period
Formula

CAPEX / Annual Savings

2026 Benchmark

4-7 years C&I rooftop; 6-10 years utility-scale depending on PPA

Solar Financing FAQ

What's the #1 mistake B2B buyers make in solar financing?

Underestimating the cost of non-production time. Every week delay between CAPEX signing and commissioning = 1/52 of first-year revenue lost (never recovered). For a $1M project generating $200K/yr, that's ~$4K per week. Rushing equipment selection or cutting corners on EPC contract terms to save 1% CAPEX often loses 3-5x that in delays. Budget 10-15% more contingency + pick proven suppliers.

How do I calculate LCOE for my project?

LCOE = (Total Lifetime Cost) ÷ (Total Lifetime Energy) ÷ Discount factor. Total lifetime cost = CAPEX + sum of OPEX over project life, discounted. Total lifetime energy = Year-1 output × (1 - degradation)^t summed. Use our free ROI calculator which computes LCOE automatically once you enter system size, location, and CAPEX.

When should I use a PPA vs CAPEX?

CAPEX (buy outright) when: you have cash or cheap debt; want maximum long-term savings; plan to own the property 10+ years; in a market with valuable tax incentives. PPA when: zero CAPEX is mandatory; you want instant guaranteed savings without capital outlay; you need off-balance-sheet treatment; you don't want O&M responsibility. For most C&I buyers with capital, CAPEX produces better 25-year NPV by 30-50%.

How much does the module $/W affect project IRR?

Significantly. Modules are typically 25-35% of total CAPEX. A $0.02/W savings on modules (e.g. JUSTSOLAR factory-direct vs Tier-1 distributor) on a 1 MW project = $20K CAPEX saved. At 20% IRR baseline, that's equivalent to adding ~1.2 percentage points to IRR. Over 25 years, compounds to $50-80K NPV improvement. Hence the rationale for sourcing modules direct from factory vs branded distributors.

Can I finance module purchases separately from EPC?

Yes — this is called equipment finance or trade finance, common for larger orders. JUSTSOLAR can provide lender documentation for project review, but payment terms are confirmed only in the formal PI or signed contract. For new buyers and most first orders, standard is 100% T/T before shipment. Any bank-instrument or milestone-payment exception requires written approval from Frank.

What's the typical bankability requirement for utility-scale?

For project-financed utility-scale (20+ MW): (a) BNEF Tier-1 module (currently ~30 brands qualify), (b) 25+30 year warranty backed by manufacturer, (c) PPA with creditworthy offtaker, (d) bankable EPC contractor with performance guarantees. JUSTSOLAR is Tier-1 adjacent — we can supply as sub-supplier under a Tier-1 branded module wrap for bankability if needed. For C&I and distributed generation (under 20 MW), we supply directly without the bankability constraint.

Financing Ready? Start With Module Sourcing.

Modules are 25-35% of CAPEX. Factory-direct sourcing from JUSTSOLAR saves 10-15% $/W vs Tier-1 distributors — directly improving project IRR by 1-2 percentage points.

Also see: Wholesale Prices · B2B Buyer's Guide