Tissot’s iconic Noughties PRC with its instantly recognisable dodecagonal bezel is back, but with one crucial difference – this time it’s solar powered. Though you wouldn’t know it to look at it, thanks to some technical wizardry that Tissot has been working on.

‘We have been investing in solar technology for a while now,’ explains Tissot’s CEO Sylvain Dolla. ‘It is a technology that has been developed and tested extensively over the past 10 years, initially in our solar-connected watches. The Lightmaster Solar Technology has been specifically adapted to work with transparent solar cells for analogue timepieces for the PRC 100 Solar.’

What Dolla is referring to is that the solar cells, usually integrated into the dial have, on the new PRC been incorporated into the sapphire crystal, making for an uninterrupted dial as well a superior light capture. Solar-powered watches work by using photovoltaic (“photo” = light, “voltaic” = electricity) cells to convert light energy into electrical energy. Invariably made from silicon, which is semi-conductive and able to convert light into electricity, these cells turn photons into electrons, conducting them from negative to positive, and from cells with an abundance of electrons to those with a deficit, which causes them to flow. 

When a photon particle from sunlight hits the cell’s surface, this absorbed sunlight dislodges electrons from the silicon atoms of the cell. This makes them exited causing them to be released from their parent atoms, which in turn moves them into a state that makes them more reactive. These overexcited electrons are eventually kicked out of the atom, which allows them to freely roam around the semi-conductor – think a toddler on a sugar high, let loose at a soft-play centre. When they are kicked out, this creates a hole, which, if this occurs in an electric field will cause the electrons from one silicon layer to move into the holes in the other layer. If you connect these two layers with metallic wire, the crossing between the two, at a point known as the depletion zone, creates a flow of electricity. In a watch, this electrical energy is passed into the battery, where it is slowly released. 

What is amazing about the new PRC’s solar technology – PRC stands for “precise, robust, and classic” – is that its cells are constructed in a tightly tessellated honeycomb structure. This allows for more efficient light capture and energy conversion, meaning that just 10 minutes of light exposure – any light, that is, this Tissot isn’t sun-centric – will charge the battery for 24 hours. Leave it in a cupboard up to 14 months and it will still come out ticking. If that wasn’t impressive enough, Tissot hasn’t let technology get in the way of good design and it hasn’t compromised on price either.

‘We have always strived to produce watches first and foremost that prioritise the aesthetics of a beautiful traditional watch, while adding useful functionalities,’ says Dolla. ‘Our priority was always the watch aesthetic, however the transparent cells come at a certain cost. This is where being a volume brand is our strength. Thanks to volume and economy of scale we are able to create and offer innovative products such as these, while still remaining within our price point.’

There are five versions of the new PRC. The stainless-steel option has two dial colours – silver sunray or a gorgeous deep blue. There are two leather straps – a classic brown leather with stainless steel case combination or the more muscular all-black version. The star of the show is the full-black model with matching bracelet – it’s sinuous, sexy and the perfect all-rounder whether you’re under blue skies or moonlit ones. 

Tissot PRC 100 Solar Quartz 39mm from £410 on brown leather with stainless-steel case; tissot.com