Sphere solar technology

Keep on charging.

Partial shade is a fact of life on caravan roofs. Sphere Twin Cell Technology helps reduce its impact by splitting the panel into two isolated circuit paths that can work independently.

How does it work? See the panels

Real-world touring

The problem is already on your roof.

Air conditioners, roof vents, antennas and nearby trees can cast shade across a solar panel. In a conventional series-connected panel, the same current has to pass through each cell in the string. A shaded cell can therefore act as a bottleneck and sharply reduce the output of the affected circuit. Bypass diodes can help by routing current around shaded sections, but that still comes with a loss of usable panel voltage and power. Twin Cell is designed around the reality that a caravan roof is rarely a perfect, obstruction-free surface.

Aerial view showing solar panels installed on a caravan roof

Roof-mounted accessories and changing sun angles make partial shade difficult to avoid.

How Twin Cell works

One panel. Two independent paths.

See how the same shade event can affect a conventional series-connected panel compared with Sphere Twin Cell Technology. In a conventional panel, shaded cells can restrict current through the series string, creating a bottleneck. Twin Cell divides the panel into two isolated circuit paths so the unshaded side can keep working independently.

Move the shade across both panels.

Drag directly across either panel, or choose a shade level. Both panels move together so you can compare the same shade event side by side.

Drag shade across the panels

Standard solar panel

Series-connected circuit

100%

What happens

Full sun. The conventional panel is operating at 100% of its rated reference output.

Sphere Twin Cell

Two isolated circuits

Circuit path A

Circuit path B

260W

What happens

Both independent paths are receiving sun.

Why the bottleneck happens: cells in a conventional module are commonly connected in series, so they carry the same current. When one cell is shaded, it can constrain the string. Bypass diodes can route around affected cell groups, but doing so still reduces usable voltage and power. Exact losses depend on panel design, shade pattern and bypass-diode layout.

Watch the technology

See Twin Cell in action.

A visual explanation of why partial shade affects conventional panels and how Twin Cell's two independent circuit paths help reduce that impact.

Choose by roof space

Find the output that fits the footprint.

The right panel starts with the space available on your roof. Twin Cell V2 steps up in length as output increases, so you can match the panel to the usable area around vents, air conditioners and other equipment.

105WCompact V2 footprint
670mm wide

135WCompact V2 footprint
670mm wide

210W670 × 1480mm
Standard or High Voltage

260W670 × 1850mm
Standard or High Voltage

System choice

Standard or High Voltage?

Both use Twin Cell Technology. The difference is how the panel fits into the electrical system.

Standard voltage

A straightforward choice for compatible caravan and RV solar systems where the panel's normal voltage and current suit the existing controller, cabling and system design.

Always match panel configuration to the requirements of the complete solar system.

High Voltage

Designed to provide more flexibility in multi-panel system layouts. Sphere notes that higher-voltage panels can allow additional panels in a string without exceeding the current rating of existing cabling.

For 12V battery charging, Sphere states that High Voltage panels require an MPPT-style solar charger.