Author and solar reviewer
Marcus Vance
Clean Energy Consultant and Web Developer
Marcus Vance is a clean energy consultant and web developer dedicated to making solar energy accessible and transparent for homeowners. With more than eight years of experience in residential solar estimation and renewable energy system design, he created Wattcrunch to help homeowners estimate panel requirements, installation costs, and long-term utility savings.
See review standardsRole
Solar calculator lead
Designs and reviews consumer-facing solar estimation tools.
Education
Electrical engineering
B.S. in Electrical Engineering, The City College of New York (CCNY)
Professional credential
NABCEP Associate
Credential information can be checked through NABCEP's official website.
Solar experience
8+ years designing and consulting on residential and light commercial solar PV installations.
Specialties
- Net metering calculations
- Solar payback periods
- Local incentives in the New York, New Jersey, and Connecticut region
- Algorithmic solar estimation tools for consumer websites
Education and credential
Education: B.S. in Electrical Engineering, The City College of New York (CCNY)
Certification: NABCEP Associate Certification
Verify NABCEP certification informationWhat Marcus does at Wattcrunch
Marcus leads the design and review of Wattcrunch's solar calculators, including system sizing, production, savings, payback, net metering, incentives, and quote analysis. He focuses on making assumptions visible and separating a planning estimate from a licensed installer's site survey, utility approval, tax advice, or financial recommendation.
Wattcrunch is an independent planning resource. Marcus's work does not represent an installer, lender, utility, government agency, or tax adviser. Read the full source hierarchy, update process, and limitations in the methodology and editorial policy.
Marcus's review standards
Wattcrunch pages are reviewed for visible assumptions, understandable formulas, and links to primary sources. Policy-sensitive claims should be checked against the current utility tariff, state program, DSIRE record, or government publication before a homeowner makes a financial decision.
Guides by Marcus Vance
Why Is My Electric Bill Still High After Solar Panels?
Separate grid imports, export credits and fixed charges after solar. Compare a worked bill example and diagnose tariff, usage and production problems.
Published 2026-10-11
Solar Loan Dealer Fees: Compare Cash Price and Financed Cost
Compare cash and financed solar prices, monthly payments and total repayment. Use a worked dealer-fee example and a lender verification checklist.
Published 2026-10-11
How to Calculate Appliance Electricity Use in kWh
Calculate appliance energy from watts and operating hours. Follow a worked electricity-bill example, account for duty cycles and check measured usage in kWh.
Published 2026-10-06
How Many Solar Panels Do I Need? A Simple 2026 Guide
A step-by-step guide to sizing a home solar system from your electricity bill, including a worked example and the role of sun hours.
Published 2026-01-15 · Reviewed 2026-06-15
Solar Payback Period Explained (With Real Numbers)
What solar payback period means, how to calculate it, and the typical range for US homeowners now that the federal tax credit has ended.
Published 2026-02-10 · Reviewed 2026-06-15
Time-of-Use Rates and Solar: What Changed and Why It Matters
TOU electricity rates are now the default for millions of US solar owners. Here is how they work, how they change solar economics, and when a battery actually pays off.
Published 2026-03-15 · Reviewed 2026-06-15
Is Solar Still Worth It in 2026? The Honest Answer.
Is home solar still worth it after the federal credit ended? Compare 2026 costs, remaining incentives, electricity rates, savings, and payback factors.
Published 2026-04-01 · Reviewed 2026-06-15
How to Compare Solar Quotes: The Only 5 Numbers That Matter
Most homeowners compare solar quotes wrong - focusing on monthly payment instead of total value. Here are the five numbers that actually determine which quote wins.
Published 2026-05-01 · Reviewed 2026-06-15
Home Battery Backup Sizing: Usable kWh, Power and Runtime
Estimate battery backup from measured loads, usable energy and reserve. Compare runtime examples, continuous power, surge and one-way versus round-trip losses.
Published 2026-05-15 · Reviewed 2026-10-12
Solar Shading Loss: Trees, Roof Obstacles & Inverters
Learn how trees and roof obstacles reduce solar output, how to estimate shading loss, and when microinverters or power optimizers may help.
Published 2026-05-20 · Reviewed 2026-06-15
Heat Pump + Solar: Sizing, Costs & Savings (2026)
Learn how to size solar for a heat pump replacing gas, oil, or propane heating, including climate, COP, electricity use, costs, and payback.
Published 2026-06-01 · Reviewed 2026-06-15
How Long Do Solar Panels Last? Lifespan & Degradation
Solar panels commonly carry 25-year production warranties and may operate longer. See research on lifespan, degradation, failures, and replacement timing.
Published 2026-06-05 · Reviewed 2026-06-15
Solar Panel Degradation Rate & 25-Year Savings
Solar panels lose output gradually over time. Here is exactly how degradation affects your 25-year savings projections and which panels degrade slowest.
Published 2026-06-08 · Reviewed 2026-06-15
Community Solar vs Rooftop Solar: Which Is Right for You?
Compare community solar and rooftop solar on eligibility, upfront cost, bill savings, contracts, maintenance, risk, flexibility, and moving homes.
Published 2026-06-10 · Reviewed 2026-06-15
Solar for Renters: 5 Options Without a Rooftop
You do not need to own a home to benefit from solar. Here are five real options for renters and apartment dwellers to reduce electricity bills with solar in 2026.
Published 2026-06-12 · Reviewed 2026-06-15
Net Metering by State (2026): Export Credit Guide
Compare 2026 net metering and solar export-credit approaches by state, including full retail credit, net billing, and avoided-cost compensation.
Published 2026-06-15 · Reviewed 2026-06-15