THE JOURNAL
What we learn on other people's roofs
Measurements rather than marketing. Everything here comes from systems we monitor, and where we were wrong about something we have said so.
LONG READ · MAINTENANCE
We washed twelve arrays in January and measured everything
Every solar company in Accra tells customers to clean their panels after harmattan. Almost none of them can say what it is worth, so in January we took twelve systems we monitor, recorded a fortnight of output before the wash and a fortnight after, and normalised both against irradiance.
The spread was enormous. The worst array — a flat roof beside an unpaved road in Amasaman — had lost twenty-three per cent. The best, shaded by a mango tree in Labone and washed by the tree's own drip, had lost four. Roof pitch mattered more than distance from the road, and nothing mattered as much as whether the site had bare ground upwind of it.
Read the full studyTHE JOURNAL
What we have learned on other people's roofs
Measurements, not marketing. Everything here comes from systems we monitor.
Maintenance
What harmattan dust really costs your array
We measured the same twelve roofs before and after a wash in January. The worst had lost twenty-three per cent of its output; the best, still under trees, had lost four.
Read the guide
Storage
Lithium or lead: the honest comparison
Lead-acid is half the price and a third of the life. Here is the arithmetic over ten years, with the replacement cycles nobody puts in the quote.
Read the guide
Regulation
Net metering, step by step
The forms, the fees, the inspection and the realistic timeline for a domestic net-metering application in Greater Accra in 2026.
Read the guideTHE ARCHIVE
Everything else we have published
Written by the people who did the measuring. Nothing here is sponsored and nothing links to a product page.
Sizing
Why your inverter should be smaller than your array
Oversizing the DC side by twenty to thirty per cent gives you more usable energy on cloudy mornings and costs almost nothing. The arithmetic, and the point past which it stops being true in Accra's irradiance.
Tariff
Reading your ECG bill properly before you buy anything
Which line on the bill actually tells you your consumption, why the lifeline band distorts the payback arithmetic for small households, and what to photograph before your survey.
Installation
Clamps, hooks and the holes you should refuse
How panels should be fixed to aluzinc, to standing seam and to clay tile — and why a contractor who wants to drill your sheet and seal it with silicone is telling you something about the rest of the job.
Storage
Sizing a battery for June, not for January
Three months of measured data from four Accra systems through the major rains, and what it implies about the storage figure you should be quoted.
Comparison
What the generator actually costs per kilowatt-hour
Fuel, oil, filters, the annual service and the rebuild at four thousand hours, worked through on a 6.5 kVA petrol set — against the same energy from an array.
THE SURVEY IS FREE
Find out what your roof is worth
Ninety minutes on site, a shading study, a modelled monthly yield and a written price. Nothing to pay, and the report is yours whether you use us or not.