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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Bifacial Panels: What Is Under the Array Decides
Rear-side generation depends on the surface beneath and on mounting height. Where the gain is real, and where flush roof mounting makes it close to pointless.
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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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Half-Cut Cells: Less Current, Less Loss, Less Shade
Cutting cells halves the current per cell, which cuts resistive loss and changes how shade propagates. Why the module splits into two halves electrically.
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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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Curtailment: Generation Deliberately Reduced
Export limits, negative prices and grid stability all cut output. Inverter clipping is a design choice and is not the same thing as curtailment.
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Demand Charges: Billed on the Peak, Not the Total
Billed on the highest interval rather than total consumption, which is why solar alone can cut energy cost while leaving the demand charge untouched.
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Grid-Tied vs Off-Grid vs Hybrid: What Each System Does
Compare grid-tied, off-grid, and hybrid solar systems: how they work, when each fits, and what to check with your utility before choosing.
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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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Solar Interconnection and Permission to Operate
Understand the utility approval process for solar: from application to permission to operate, including delays and common misconceptions.
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.
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Why an Array Never Makes Its Rated Power
Understand why solar panels produce less than rated power. Explore temperature, soiling, mismatch, wiring, and inverter losses, plus how to diagnose low output.
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Arc Fault Protection in PV: Why DC Arcs Persist
A DC arc has no zero crossing to extinguish it. Series against parallel faults, and why repeated trips are an instruction to inspect rather than reset.
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Solar Battery Types: Lead-Acid, AGM, and Lithium
Compare lead-acid, AGM, and lithium batteries for solar: usable depth, cycle life, charging, and temperature effects. Understand the trade-offs to choose correctly.
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Combiner Boxes: Where Strings Meet and Fuses Appear
Several strings joined at one point, and the protection question that follows: fuses are needed once enough parallel strings can backfeed a fault.
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Battery Bank Sizing: From Daily Load to Nameplate Capacity
Learn how to size a battery bank correctly: daily load, depth of discharge, round-trip efficiency, days of autonomy, and temperature derates.
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Depth of Discharge: What It Means for Battery Life
Depth of discharge (DoD) defines usable battery capacity. Learn how DoD affects cycle life, why chemistry matters, and how to calculate it.
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.
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Solar Panel Cleaning: When It Helps and When It Doesn't
Learn when solar panel cleaning is worth it, what rain already does, and what damages panels. Honest guide to production gains and safe methods.
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Solar Panel Degradation: Rates, Warranties, and Failures
Learn how solar panels degrade over time, what performance warranties cover, and how to distinguish normal degradation from failure.
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Solar Monitoring: Reading Production Graphs and Spotting Faults
Learn how to read solar production graphs, distinguish normal behavior from faults, and use monitoring to verify system performance.
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Solar Panel Shading: What It Costs and Why
How shade affects solar panels, why one shaded cell hurts the whole string, bypass diodes, and design fixes. Understand partial shading losses.
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Solar Panels in Snow, Hail and Storms: What to Expect
How snow, hail, and storms affect solar panel performance and durability. Learn what is normal, what is damage, and when to take action.
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Solar Panel Warranty: Product, Performance, Workmanship
Understand the three types of solar warranties: product, performance, and workmanship. Learn what each covers and what to check in your contract.
Where it gets installed
Residential, commercial, agricultural and shared. Different economics, different structures, different questions — and the ownership decision that outlasts all of them.
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Agrivoltaics: Crops and Solar on the Same Land
How agrivoltaics combines crop production with solar panels: spacing, height, shade tolerance, and current practice.
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Commercial Roof Solar: Mounting, Roof Life, and Load
Learn how commercial roof solar differs from residential: ballasted vs. penetrating mounts, membrane warranties, structural load, and roof lifespan.
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Commercial Solar Systems: How They Differ from Residential
Commercial solar systems differ from residential in demand charges, three-phase power, roof structure, and scale. Learn what to evaluate for your business.
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Charging an EV With Solar: Timing Is the Problem
Generation peaks midday and most charging happens at night. The options are scheduling, a battery, or export and import under whatever tariff applies.
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Ground Mount Systems: Foundations, Trenching, Access
When the roof is wrong: foundation types against frost depth and soil, the trench run where voltage drop bites, and access for mowing and clearing.
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Residential Solar: From Proposal to Operation
Learn the step-by-step process of getting residential solar, from site assessment to interconnection, and where key decisions are made.
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.