How it works, before what it costs
How it works, before what it costs.
Almost every page about solar is trying to get you a quote. This one explains the machinery instead — what a cell does with light, why the meter runs backwards, and why the array on the datasheet is not the array on the roof.
Search for anything about solar and you land on a page built to capture your postcode. The information is not always wrong, but it is written by someone paid on your enquiry, and that shapes what gets explained and what gets skipped.
What gets skipped
Why a grid-tied system shuts down during a blackout, and what it costs to change that. What net metering actually credits you, and why the rate matters more than the number of panels. Why panels produce less in heat, so the best day of the year is cold and bright. Why the 400-watt panel on the datasheet makes closer to 300 on a roof, and which of those losses are fixable.
What this site does not do
No quotes, no installer referrals and no advertising. No prices, because a price depends on your roof, your utility and a policy that changes every couple of years, and a number published today is misleading by the time it is read. Where cost drives a decision, the page explains what moves it and where a current figure comes from.
About this domain
This address carried a solar news blog for about fifteen years, and its archive is largely corporate announcements from 2009. None of that is restored: a press release about a plant that opened in 2010 helps nobody now. What is here is new, and it is written to stay true rather than to be current.
From photon to power point
What a cell does with light, what the inverter is for, and why a 400-watt panel almost never makes 400 watts. The mechanism, before anything else.
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Solar DC or AC: How Panels Produce and Convert Power
Solar panels produce DC electricity; homes use AC. Learn why conversion is needed, the losses involved, and why both currents are essential in a PV system.
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How Solar Panels Work: Photovoltaic Cells Explained
Understand how photovoltaic cells turn sunlight into DC electricity, the role of inverters, and how the system connects to your home. A clear, technical explanation.
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How Solar Panels Produce Electricity
Learn how solar panels convert sunlight into electricity, from photons to AC power, and discover the key factors that affect their energy output.
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Solar Panel Efficiency: What the Datasheet Number Means
Understand what solar panel efficiency measures, why higher efficiency isn't always better, and when it truly matters for your roof.
Where the extra electricity goes
Net metering, export tariffs, interconnection and why a grid-tied system switches itself off in a blackout. Rules are set by state and utility, and the pages say which.
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Feed-in Tariffs and Export Payments: How They Work
Understand feed-in tariffs vs export payments, how solar export compensation works, and key differences from net metering. Check local rules.
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Grid-Tied Solar: How It Works and What Happens in an Outage
Understand grid-tied solar systems: how they connect to the utility, why they shut off during outages (anti-islanding), and what rules vary by state.
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Net Metering: How It Works and What to Check
Understand net metering: how the meter runs backward, buy-all vs. sell-all, and why credit rates matter more than panel count. Rules vary by state.
Designing the system
Series or parallel, MPPT or PWM, how big a controller and how thick a cable. The calculable half — standards and arithmetic rather than opinion.
What it does over twenty years
Degradation, shading, heat, weather and warranties — what an underperforming system is usually telling you, and how to tell normal from broken.
The questions people arrive with
Why doesn't my solar work when the power goes out?
A grid-tied inverter is required to disconnect the moment it stops seeing the grid. If it kept exporting, it would energise lines that utility crews believe are dead. Continuing to run during an outage needs equipment that can isolate your house from the grid first — a battery with a backup-capable inverter, or a specific transfer arrangement.
Do solar panels work better in hot weather?
No, the opposite. Output falls as cell temperature rises, at a rate given on the datasheet as the temperature coefficient. A panel makes more power on a cold clear day than on a hot one with the same sunlight, which is why annual production in a cool sunny climate can beat a hotter one.
Should panels be wired in series or in parallel?
It depends on what the inverter or charge controller expects. Series adds voltage while current stays the same; parallel adds current at the same voltage. The equipment has a maximum input voltage and a maximum current, and the string design has to stay inside both — including the voltage rise that happens on a cold morning.
Why does my system produce less than the panels are rated for?
Ratings are measured at standard test conditions that a roof rarely matches. Between the datasheet and the meter you lose output to cell temperature, soiling, module mismatch, wiring resistance and inversion. A well-designed system delivering meaningfully below the sum of its panel ratings is normal, not faulty.