Solar Basics
A shadow on one corner costs far more than one corner
Cells wired in series must all carry the same current, so the darkest cell sets the limit for everything…
· 4 min read
Solar Basics
Panels, orientation, shading and what a quoted figure really means.
20 articles · page 1 of 2
Why the optimum tilt for an array is flatter than people expect
The old rule of setting tilt equal to latitude optimises for one moment in the year, and annual energy prefers something shallower.
By Daniel Okonkwo · · 4 min read
Solar Basics
What standard test conditions measure, and why a roof never provides them
A panel’s rated wattage is its output at one irradiance, one cell temperature and one atmospheric path, and…
· 4 min read
Solar Basics
Panels degrade, and the first year does not resemble the rest
Output falls along two separate curves — a small initial drop in the first weeks of exposure, then a slow…
· 4 min read
Solar Basics
Optimisers and microinverters fix different halves of the same problem
Both put electronics under every panel and both are sold as a shading remedy, but they split the work…
· 4 min read
Solar Basics
Monitoring only helps once you know what a dull week looks like
A generation figure carries no diagnostic weight on its own, and the useful skill is separating ordinary…
· 4 min read
Solar Basics
Cleaning panels repays in some climates and almost none of them
Rain does the job free above a certain tilt, so paid cleaning only makes sense where soiling is chronic…
· 4 min read
Solar Basics
What a panel is actually rated to survive: hail, snow and mechanical load
Modules are tested against defined impacts and defined pressures, and knowing what those tests represent…
· 4 min read
Solar Basics
Bifacial modules and trackers are sound ideas that rarely fit a house
Both technologies earn their keep at utility scale for reasons that a flush-mounted domestic roof cannot…
· 4 min read
Solar Basics
Ground mount versus roof, and what changes when the array leaves the building
A ground-mounted array buys ideal orientation, cool running and easy access, and pays for it in…
· 4 min read
Solar Basics
What a performance warranty on a panel actually promises
The product warranty and the performance warranty cover entirely different failures, and the longer of the…
· 4 min read
Solar Basics
An array is sized against the household, not against the roof
Filling the available area is the default approach and it produces systems whose last few panels earn a…
· 4 min read