Solar Energy Guides

Expert-written guides to help you navigate solar tax credits, incentives, and policy changes in 2026.

Tax Credits18 min read

Solar Tax Credit Guide 2026 — What Changed & What Didn't After OBBBA

The definitive guide to federal solar tax credits after the OBBBA. Section 25D expired, Section 48E remains — learn exactly what you qualify for.

Tax Credits10 min read

ITC vs PTC: Which Was Better — and What's Left After the Deadline?

The 48E ITC and 45Y PTC construction-start deadline (statutory July 4, 2026; rolled to Monday, July 6 under IRC 7503) has passed — neither credit is claimable for new projects. How the choice worked, what grandfathered projects keep, and what still moves the economics.

Bonus Credits9 min read

Domestic Content Bonus: How to Qualify for the 10% Adder

Learn how to qualify for the 10% domestic content bonus on top of the 30% solar ITC. Covers US-made requirements and FEOC rules.

Tax Credits9 min read

Section 48E Pass-Through: What Grandfathered Lease/PPA Customers Keep

The Section 48E construction-start deadline (statutory July 4, 2026; rolled to Monday, July 6 under IRC 7503) has passed. Only grandfathered lease/PPA projects with a documented pre-deadline construction start still carry the 30% via the commercial Section 48E pass-through.

Tax Credits8 min read

Commercial vs Residential Solar Tax Credits (2026)

Commercial properties could claim the 30% ITC plus depreciation if construction began before July 4, 2026 (deadline now passed). Residential owned systems lost the federal credit. Compare the two.

State Incentives12 min read

State Solar Tax Credits That Stack With Federal Incentives

State incentives operate independently from federal rules and remain available. Some states even expanded programs after the federal credit expired.

Tax Credits9 min read

Rental Property Solar Tax Credits: What Still Applies in 2026

Rental properties qualified under Section 48E — landlords could claim the 30% credit plus depreciation benefits if construction began before July 4, 2026 (deadline now passed). 100% bonus depreciation, MACRS, and state credits still apply.

Tax Planning7 min read

What If My Tax Liability Is Less Than the Solar Tax Credit?

Learn carryforward and carryback rules for unused solar tax credits. Strategies to maximize credit value.

Installer Vetting14 min read

Installer Financial Health Guide — Freedom Forever Bankruptcy & How to Vet Your Installer

America's #1 solar installer filed bankruptcy in 2026. Learn the 5 questions, red flags, and warranty risks to check before you sign any solar contract.

Installer Transparency8 min read

How to Ask Your Solar Installer About 48E Tax Credit Passthrough

Solar lessors have no obligation to pass through the 30% Section 48E credit. Learn the 3 passthrough patterns (Aggressive, Partial, None) and the one question to ask before you sign.

Financing12 min read

Solar Lease vs PPA vs Buy After July 4, 2026: A Homeowner's Decision Guide

Step-by-step guide for homeowners deciding between lease, PPA, or cash purchase after the 48E deadline. Compare costs, understand 48E passthrough, and know exactly what to ask installers.

Rates & Payback12 min read

Electricity Rates by State in 2026: The Complete 50-State Guide

Compare residential electricity rates across all 50 states and DC for 2026 - and see exactly how your rate drives solar payback. National average, rankings, and sortable table.

Financing8 min read

Post-48E Solar Financing: Cash vs Loan vs Lease vs PPA

After the 25D credit expired, solar financing economics inverted. This unified, post-48E decision guide compares cash, loan, lease, and PPA - and tells you which wins for your bill size and time horizon.

Equipment & Durability10 min read

How Long Do Solar Panels Last? Degradation & Warranty Data (2026)

Most solar panels are warrantied for 25-30 years and keep producing at reduced output for 40+. Real degradation math (0.25-0.75%/yr by tier), the actual warranty distribution across 5,285 panel models, and when replacement pays for itself.

Batteries11 min read

How to Add a Battery to an Existing Solar System (2026)

Can I add a battery to my existing solar panels? Yes — if the coupling is right. AC-coupled vs DC-coupled decision path, three retrofit-ready batteries (Powerwall 3 + Tesla lease, aPower 2, Enphase 10C), and the post-48E lease-vs-own math with $0 federal credit.

Policy12 min read

Plug-In Solar: The Complete 2026 Guide (Legality, Costs, Safety)

Balcony solar kits plug into a 120V outlet with no rooftop install. 10 states have passed plug-in solar laws since Utah's HB 340. See the verified legality map, kit costs from sub-$1K, savings math, and UL 1741 safety rules.

Need a quick answer?

Check your tax credit eligibility in 30 seconds with our free ITC Status Check tool.

Check My ITC Status

Written & reviewed by

EnergyTools Research Team — Solar Energy Research Group

The EnergyTools Research Team compiles and verifies residential solar data from NREL, EPA, and state utility commissions. Methodology is reviewed quarterly.

  • Source data: NREL PVWatts V8 + Utility Rates V3 APIs
  • Source data: EPA FuelEconomy.gov vehicle efficiency data
  • Methodology reviewed quarterly

Methodology & data sources:NREL PVWatts, EPA FuelEconomy.gov, state utility commissions— updated 2026.