Learning center
WattBarn briefings
WattBarn runs the real math on home solar and battery storage: payback, cost, and savings by state, with a free calculator and no sales pitch.
33 briefings and counting. Newest first, every number sourced.
Newest briefingCommunity Solar: How It Works and Who It Fits
This briefing explains community solar for renters and shaded roofs: how the bill credit works, what the subscription discount really is, and the terms to read first.
Owning & MaintainingCan Solar Panels Catch Fire? Real Risks and Extreme Heat
This safety briefing answers can solar panels catch fire: why fires are rare, the real risk factors, what extreme heat does, and what actually reduces risk.
BasicsSolar Inverter vs Battery: The Difference and Do You Need Both
This explainer covers the difference between a solar inverter and a battery: what each does, DC to AC conversion vs storage, costs, and whether you need both.
BasicsSolar Panel Efficiency: What the Percentage Means
This teardown explains solar panel efficiency: what the percentage measures, typical ratings by panel type, and when paying extra for it is actually worth it.
Getting StartedTypes of Solar Panels: Mono, Poly, and Thin Film
This breakdown compares the types of solar panels, monocrystalline, polycrystalline, and thin film, on efficiency, cost, lifespan, looks, and roof space.
Saving on EnergyWhat Is a Kilowatt-Hour? kWh in Plain English
This explainer covers what a kilowatt-hour is, how a kWh shows up on your electric bill, what appliances use, and how it drives solar sizing and savings.
CostSolar Panel Maintenance Cost: What to Expect
This cost note breaks down solar panel maintenance cost item by item, from cleaning to the mid-life inverter, so you can budget for the whole 25-year life.
BasicsDo Solar Panels Work on Cloudy Days?
This briefing answers do solar panels work on cloudy days: yes, at reduced output, with diffuse-light physics, cloud versus shade, and rain and snow facts.
FinancingSolar Lease vs Buy: Which Saves More?
This breakdown compares the four ways to pay for home solar, cash, loan, lease, and PPA, and shows why owning captures far more lifetime savings over time.
BasicsWhat Is Net Metering? (How Solar Credits Work)
This explainer covers what net metering is: how a utility credits the excess solar you send to the grid, how those credits roll over, and why the rate varies.
CostSolar Water Heaters: Cost & How They Work
Solar water heaters use rooftop collectors and a tank to cut hot-water bills. This briefing covers how they work, cost, illustrative payback, and sizing.
Owning & MaintainingHow to Monitor Your Solar Production (6 Steps)
This walkthrough shows how to monitor solar panel output in six steps, from reading your inverter app to spotting a real fault before it costs you.
BatteriesHow to Add a Battery to a Solar System (Steps)
This field guide adds a battery to solar panels in seven steps: sizing, AC vs DC coupling, inverter compatibility, permits, cost, and installer vs DIY safety.
SizingSolar Sizing Reference: kWh, Watts, and Sun Hours
This reference tables the stable solar math: annual kWh to system size, panel counts at common wattages, and daily production by peak sun hours, with worked examples.
Getting StartedSolar Panel Installer: How to Choose One in 7 Steps
Solar panel installer vetting in seven steps: gather three quotes, compare price per watt, verify licensing and insurance, weigh warranties, spot red flags.
Getting StartedHow to Read a Solar Quote (7 Steps)
This field guide shows how to read a solar proposal in seven steps: system size, price per watt, production, payment terms, and red flags before you sign.
Owning & MaintainingHow to Clean Solar Panels (Safely, 6 Steps)
This field guide shows how to clean solar panels safely in six steps, from deciding if they need it to doing it from the ground, so you skip a costly fall.
Getting StartedSolar Panel Installation: How to Go Solar (7 Steps)
Solar panel installation, end to end: how to go solar in seven steps, from roof fit check to install day and utility turn-on, and the numbers to run yourself.
Owning & MaintainingHow to Maintain Solar Panels (7-Step Care Guide)
This field guide shows how to maintain solar panels in seven simple steps, from monitoring to cleaning to the inverter, so you catch a costly problem early.
Saving on EnergyHow to Read Your Electric Bill (7 Steps)
This field guide shows how to read your electric bill in seven steps, decoding supply, delivery, and fees to find the true all-in rate that plans and solar.
BatteriesAre Solar Batteries Worth It? The Honest Payback Math
Are solar batteries worth it? It depends on your utility's rules. This briefing runs the honest math: cost, net metering, payback, backup value, and sizing.
SizingHow to Size a Solar System for Your Home (5 Steps)
This field guide sizes your home solar system in five steps, from annual kWh to a system size in kW and a real panel count, so you skip the one-month mistake.
LifespanHow Long Do Solar Panels Last? 25 to 30 Years
How long do solar panels last? This field guide runs the real numbers: most keep producing for 25 to 30-plus years, degrading about half a percent a year.
Home valueDo Solar Panels Increase Home Value?
This briefing answers do solar panels increase home value: yes, owned systems typically add value and sell faster, with the owned-vs-leased catch.
BasicsDo Solar Panels Work in Winter and Cloudy Weather?
This briefing answers do solar panels work in winter and cloudy weather: yes, at reduced output, with cold-efficiency physics, snow facts and seasonal math.
SizingHow Many Solar Panels Does It Take to Run an Air Conditioner?
This briefing answers how many solar panels to run an air conditioner, with the watts-times-hours sizing math and counts for window and central AC.
BatteriesHow Much Does a Tesla Powerwall Cost? Price + Installed
Tesla Powerwall cost, priced honestly: the illustrative hardware figure, the fully installed total, why the two differ by thousands, and the after-credit price.
Off-gridHow Much Does an Off-Grid Solar System Cost? The Full Price of Cutting the Cord
Off-grid solar system cost runs an illustrative $45,000 to $95,000: why the battery bank dominates the bill and how many solar panels run a house.
PaybackSolar Panel Payback Period: When Do They Pay for Themselves?
This briefing runs the break-even math on home solar: a typical payback lands near 7 to 11 years. See the formula, the variables that swing it, and the 25-year net.
SizingHow Many Solar Panels Do You Need for a House?
This briefing turns your kilowatt-hours, your sun hours, and your roof into a real panel count: the sizing formula worked in full, roof-fit limits, and one example.
BatteriesHow Many Powerwalls Do You Need? Sizing and Cost, Explained
This briefing sizes home battery count to what you actually want to back up, not to your square footage: usable kWh per unit, worked load math.
Backup powerHome Battery Backup vs Generator: Which Actually Fits Your Outages?
This briefing runs home battery backup against standby and portable generators: honest costs, runtime math, fuel logistics, and which fits your outages.
CostHow Much Do Solar Panels Cost in 2026? Full Price Breakdown, Payback, and Whether It Is Worth It
A typical home solar system costs about $2.50 to $3.50 per watt installed, or roughly $17,400 after an illustrative federal credit.