Solar technology company OPES Solutions and Europe's leading motorhome manufacturer Westfalia have developed a powerful solar solution for vehicle-integrated photovoltaics for camper vans. This is the first time that large solar panels are part of the standard vehicle configuration of Westfalia motorhomes. They can be seamlessly integrated on the roof during production. The solution includes lightweight solar modules with a dark, embossed surface and the new production line in which the solar roofs are assembled in series. The line with an automated quality control and went into operation at the beginning of 2022 at the Westfalen Mobil GmbH site in Rheda-Wiedenbrück in North Rhine-Westphalia, Germany.

Growing RV market with special requirements

The recreational vehicle industry has thrived in recent years. In Germany alone, a total of 83,500 (+25%) RVs were sold in 2021. At the same time, more and more electrical components and features increase energy demand in vehicles. The large roof areas of motorhomes are ideal for providing a reliable and environmentally friendly energy source. Vehicle-integrated photovoltaics gives greater flexibility – less dependence on the power grid, more autonomy thanks to the battery charged by the sun.

The solar modules were developed for special requirements in collaboration with Fraunhofer CSP. They are frameless, particularly light and thin, yet can withstand extreme climate and constant vibration while in operation when on- and off-road driving. Another requirement is to ensure optimal yields, even in the case of shading and low irradiation, which is achieved through innovative cell interconnection and half-cell technology.

Roof boxes or surfboards can still be transported on roof racks. The maximum peak power of 365 watt is supplied to the batteries through an efficient MPPT charge controller. The modules were first tested under laboratory conditions and then in tough field conditions. Customers can rely on mature technology by Westfalia.

“Westfalia has been setting standards in motorhome construction for decades. Innovations are, therefore, part of our DNA. We are strengthening our site in Rheda-Wiedenbrück with the new solution. With the photovoltaic roofs produced here, we can offer another unique selling point,” says Can-Kasim Dogan, Managing Director of Westfalen Mobil GmbH. The new technology is already available for the Ford and Fiat-based camper vans – other vehicle models will follow soon.

New production line for solar integration at the factory

 OPES Solutions has developed a customized assembly line for integrating the modules directly with the roof. The line ensures automated alignment and bonding on the roof to enable economical and reliable series production. The function and performance are tested and controlled in an automated production step to confirm high quality.

“Vehicle-integrated photovoltaic is not only about developing and manufacturing suitable solar technology, but always about the holistic approach to a complete solution. Photovoltaic becomes a material property producing energy, without being recognized by the customer as additional bulky construction,” says Robert Händel, founder and CEO of OPES Solutions.


You can find more information about vehicle integrated photovoltaics here.

About Westfalia

We are a medium-sized company with more than 500 employees and belong to the French Rapido Group. Our Westfalia brand is the market leader in Germany for motorhomes in the panel van segment. Premium product quality, permanent innovation and a high level of customer orientation have been enabled us to achieve this position. That is the reason why Westfalia is also recognized as a synonym for mobile leisure – in Germany and Europe.

About OPES Solutions

OPES Solutions is a leading manufacturer of custom off-grid solar panels. The company designs and produces various types of solar panels suitable for a wide range of applications, including industries where solar was not feasible before. Client-specific design, high durability and an outstanding price/performance ratio are achieved by patented manufacturing processes implemented in the OPES plant in Changzhou, China. Business & Product development are located in Berlin, Germany and Shanghai, China. The research and development partners of OPES Solutions include the Fraunhofer Center for Silicon Photovoltaics.