Transparent Solar Panels: How See-Through PV Works (2026)
Published by SEO Dons · Last reviewed October 2026
“Transparent solar panels” covers three quite different technologies, from glass you can buy for a canopy today to laboratory devices you cannot. The one rule that applies to all of them is simple: a solar cell can only turn into electricity the light it absorbs. Light that passes through to the room, the crop or the view below is light the cell has given up. Here is how each type handles that trade-off, what the research shows, and where see-through PV makes sense.
Three kinds of see-through solar
1. Spaced-cell glass. The most common product is not transparent at all at the level of the cell. Ordinary opaque silicon cells are laminated between two sheets of glass with gaps between them, so light falls through the spaces. How much light gets through is set by how far apart the cells are, and the output falls in the same proportion: halve the area of cells in a panel and you roughly halve what it can generate.
2. Thin-film tinted glass. Thin-film materials such as amorphous silicon can be deposited thinly enough that the glass looks tinted rather than blocked. The view through is even, but the film generates by absorbing part of the visible light, so the glass passes less of it. A 2022 review of semi-transparent PV glazing in UK buildings (Musameh and colleagues, Journal of Building Engineering) found that amorphous-silicon glazing can leave a building needing more heating and more artificial lighting than conventional clear double glazing would — the generation has to be weighed against what the glazing takes away.
3. Wavelength-selective “clear” solar. The newest approach leaves visible light alone and harvests only the ultraviolet and near-infrared parts of sunlight, which the eye cannot see. A team at Michigan State University led by Richard Lunt built a transparent luminescent solar concentrator on this principle: a clear plastic layer absorbs the invisible light and guides it to solar cells along the edges. When it was announced in August 2014 it converted about 1% of sunlight, and the team expected a fully optimised version to reach about 5% (pv magazine, 22 August 2014). Because a device like this ignores the visible part of the spectrum by design, it can never match an opaque panel’s output.
The trade-off: light through against power out
For an ordinary panel the question is how much it generates. For see-through PV there are two answers that pull against each other — how much light it passes and how much power it makes — and the right balance depends entirely on what is underneath.
Mounting matters as much as the glass. Transparent PV is usually fitted where glazing would go anyway: vertical facades, sloping rooflights and canopies. PVGIS, the European Commission’s solar model, shows what orientation does on its own, for any panel, near Evesham:
| South-facing panel | Output in a year (kWh per kW of panels) | Output in December (kWh per kW) |
|---|---|---|
| Tilted at 30° (a typical roof) | 985 | 29.9 |
| Vertical (a facade or window) | 720 | 38.1 |
| Flat (a horizontal rooflight) | 830 | 12.9 |
PVGIS v5.3, near Evesham (52.09°N), free-standing, south-facing, 14% system losses, queried 7 October 2026. The figures are per kW of panels, not per square metre — a see-through product has far fewer watts in each square metre than an ordinary panel.
A vertical south face gives up about a quarter of a year’s output against a 30° roof, but in December — when the sun is low — it produces more. That suits a building that needs power in winter, but the low output per square metre of see-through glass still applies on top of it.
Transparent solar on greenhouses
Storing the sun’s heat in the structure itself is a different route from generating electricity on the roof — see passive solar greenhouses for how that works in the UK.
Greenhouses are where the trade-off is sharpest, because the light passing through is the crop’s food. In a trial by Cossu and colleagues at the University of Sassari in Sardinia (Applied Energy, 2014), opaque panels covering half of a greenhouse roof — 68 kW on the south-facing slopes — cut the light reaching the crop by 64% over a year: 82% under the panels and 46% under the remaining clear cover. A 2006 review led by Leo Marcelis (Acta Horticulturae 711) found that for tomato, cucumber and sweet pepper each 1% of light is worth 0.7–1% of yield. Opaque panels on the glass rarely pay for the crop they cost.
Wavelength-selective cells are the hope for changing that. Researchers at North Carolina State University grew red leaf lettuce under filters that pass only the light semi-transparent organic solar cells would let through — cells designed to absorb the wavelengths plants use least — and found no real reduction in growth or health — leaf number, size, weight, CO2 uptake and antioxidant levels (Cell Reports Physical Science, 2021, as reported by Vegetable Growers News on 15 April 2021). The researchers suggested such cells could make many greenhouses energy-neutral, but they were still waiting for a company to produce them at scale.
For a grower deciding now, the practical answer is to keep ordinary panels on solid roofs and the ground. Our guide to solar panels for greenhouses sets out where they go on a glasshouse site, which loads they can carry, and what PVGIS says they produce month by month.
Where see-through PV makes sense today
- Glazing that would be bought anyway. Facades, rooflights and atrium roofs, where the building needs glass and the PV adds generation to it. The UK Green Building Council’s solutions library lists transparent laminate PV glass for roofs, facades and structures.
- Canopies and shelters. Car-park canopies, walkways and garden structures, where some shade is wanted and some light is welcome.
- Not for maximum output. Where the aim is simply the most electricity from a roof, an ordinary opaque panel wins on output per square metre and on cost per watt.
What do transparent solar panels cost?
There is no published UK price series for transparent or semi-transparent PV glass. It is sold as a glazing product and priced per project, so compare it with the glazing it replaces as well as with ordinary panels. For context, the government’s official solar cost statistics cover only MCS-certified installations of ordinary panels up to 50 kW; anything larger, see-through or not, is priced from itemised quotes.
The disadvantages, in short
- Less electricity per square metre than an opaque panel, by design.
- A tinted or patterned view, depending on the type.
- Fewer products and installers, and project-by-project pricing.
- In buildings, possible extra heating and lighting demand, which can offset part of the generation.
If the interest in see-through solar comes from wanting power for a greenhouse without shading it, the answer for most sites is to put ordinary panels somewhere else — a shed, packhouse or store roof nearby — and run the cable. For a small greenhouse, see whether solar greenhouse heaters work before buying a kit.