126 Solar Panels on Our Factory Roof: An Honest Look at Our First Sunny Months

We've put solar panels on the factory roof

In April 2026 we fitted 126 solar panels to the roof of our factory in Chandlers Ford, Hampshire. We're Salt of the Earth, a family-run natural deodorant manufacturer that has been making sprays, roll-ons, sticks and balms here in the UK since 1993. We're certified 100% COSMOS Natural by the Soil Association, a certified B Corp, Cruelty Free International approved, and approved by the Vegan Society.

We're rather chuffed with the panels. We're also going to be straight with you about what they do and don't do, because vague green claims help nobody.

How much of our electricity comes from solar?

Here's the interesting bit. Over a full year, the panels are estimated to generate the equivalent of around 100% of our annual electricity use. So why aren't we shouting "100% solar powered" from the rooftop (right next to the panels)? Because generating electricity and being able to use it are two different things.

Solar doesn't turn up when you'd always like it to. In summer the panels produce far more than the factory can use during the day, and the surplus is exported to the grid. In winter they produce much less, so we lean on the grid instead. Once you factor in mornings, evenings and the seasons, the share of our electricity we can actually use straight from the roof works out at around 45% across the year. That's the honest figure, and it's the one we stand behind.

What do the summer numbers actually show?

Our monitoring system tracks every unit of energy in and out. Here's what the first few months looked like:

• May 2026: solar made up almost 88% (87.98%) of all the energy flowing into the site, with the rest imported from the grid. Of the energy the system handled, about 42% powered the factory directly and around 58% was exported to the grid.
• June 2026: solar made up roughly 87% (87.32%) of energy input, with about 44% used on site and around 56% exported.
• July 2026: solar made up almost 92% (91.76%) of energy input, with about 39% used on site and around 61% exported.

Here's the important bit, and where a lot of businesses accidentally overclaim. "Solar was almost 88% of our energy input" is not the same as "solar covered 88% of our electricity use". A large chunk of what the panels make is exported rather than used by us. When you work out how much of our own consumption the panels covered directly, it's roughly 71% in May, roughly 71% in June and roughly 79% in early July. Still a lot of sunshine doing real work, just described accurately.