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.

Why is so much being exported?

Our factory mostly runs on electricity: electric forklifts, production machinery and the like. On a sunny weekday the panels comfortably out-produce daytime demand, so the extra goes to the grid. The gap is in the mornings, evenings and darker months, when the panels are quiet but the kettle, the lights and the machines still want power. That timing gap is exactly the problem batteries are built to solve, which brings us to our plans.

What's next: batteries and getting off gas

Two things are on the list, and we want to be clear that these are plans and aims rather than things we've already done.

First, battery storage. We're looking at investing in batteries in 2027 so the site can run on stored solar power in the mornings and evenings, rather than exporting the midday surplus and buying it back later. The aim is to use more of what we generate ourselves.

Second, getting gas out of the building. The factory still has an old gas central heating system. We've recently invested in electric heating and cooling for the upstairs office, and we plan to do the same downstairs, with the goal of removing gas from the building entirely over time. We're not there yet, and we'll say so until we are.

Why bother?

Because it fits what we already do. We were one of the first brands to offer refillable deodorants, back in 2013. We're a certified B Corp, a Living Wage Foundation employer, and in 2026 we were honoured with the King's Award for Enterprise for Sustainable Development. Rooftop solar on our own factory is simply the next sensible step. There's plenty of room for UK businesses to do this, too: the UK Government's Solar Roadmap (published in June 2025 by the Department for Energy Security and Net Zero) cites UK Warehousing Association research estimating that the country's largest warehouses offer around 75 million square metres of roof space, enough to support roughly 15GW of rooftop solar.

We'll keep publishing the real numbers as the seasons change, including the winter months when solar does far less. That's the deal. If you want to know more about how we back up our claims, take a look at what our COSMOS Natural certification really means.

FAQs

Is the Salt of the Earth factory powered by solar?

Over a year our 126 rooftop panels are estimated to generate the equivalent of around 100% of the site's electricity use, but because solar arrives mostly in summer and during the day, around 45% of our electricity can come directly from the panels. The rest of their output is exported to the grid.

How many solar panels does Salt of the Earth have?

126 panels, installed on the factory roof in Chandlers Ford, Hampshire, in April 2026.

Is the factory gas-free?

Not yet. The building still has an old gas central heating system. We've moved the upstairs office to electric heating and cooling and plan to do the downstairs offices next, aiming to remove gas from the building over time.

What happens to the extra solar electricity?

In sunny months the panels generate more than the factory uses during the day, and the surplus is exported to the grid. We're looking at battery storage in 2027 so we can store more of it for use in the mornings and evenings.