Solar panels on windows, façades, and roofs

Over the last few years, in the Dutch Solar Design project, we’ve been working with partners to develop technology that makes this possible. In doing so, we pay attention to aesthetics and sustainability. For example, unimaginative façades of old blocks of flats can be transformed into attractive walls that generate energy. Within the foreseeable future, we want solar panels that generate energy to cost the same as the most common materials used in construction. This is how we’ll accelerate the creation of energy-neutral houses and other buildings.

The new generation of solar panels is so flexible that you have endless possibilities in terms of size, shape, and colour pattern. Situations where solar panels have been installed on façades include:

• an image formed by aesthetic solar panels of matt glass on a concrete house along the track, at Naarden-Bussum railway station (see image)
• aesthetic solar panels on the façade of the Royal BAM Group head office, where a brick pattern was chosen that blends in seamlessly with the façade itself
• solar panels mounted in old air intakes, on the façade of Shell Technology Centre on the IJ in Amsterdam.
• Solar panels as ivy on a facade in Eindhoven.

The variety of sizes, shapes, colours, and transparency of solar panels we’re working on may reduce the yield per panel. But on the plus side, many more surfaces in the built environment are suddenly able to generate solar energy. This can significantly boost the total amount of energy generated.

We do those innovations together with companies. For example, by developing an approach that ensures solar cells can be incorporated flexibly and affordably into surfaces and objects. From solar roofs and facades to on cars. We have built a research pilot line for this purpose. This is a model for a new generation of factories that will produce flexible semi-finished products with solar power.

Variations in shape, size, and colour are also important for the wider acceptance of solar panels. And to ensure that using solar power doesn’t undermine an architect’s creative freedom. Moreover, these innovative solutions create new market combinations and business activities. There are opportunities for construction companies, suppliers, machine manufacturers, and installation engineers.

An important aspect of solar panels is fire safety. Together with various parties, we examine existing solar panels and systems and develop new products. These include solutions to minimise the risk of arcs or new technology that prevents hotspots caused by shade.

We also provide expertise on solar modules and systems in relation to power electronics for various parties. We do this with our state-of-the-art test facilities for measuring, analysing and characterising these modules.

For solar windows, we use thin-film solar cells, produced mainly from the material perovskite. The goal is to create glass that lets in at least 20% of sunlight, while converting at least 10% into solar power. In this way, the windows can help make buildings energy-neutral, for example.

We’ve created a working prototype glass window that generates solar energy. Together with companies in the construction and glass industries, we’re developing this further so that it can be marketed. The prototype is 10 by 10 centimetres, with 5% efficiency. If we remove 50% of the material, 40% of the yield remains. Within 2 years, we want to improve the 5% efficiency rate to 10%, without compromising on aesthetics or transparency.

We work together with market parties on innovations in photovoltaic-thermal systems (PV-T systems). To make them better and more affordable, among other things. PV-T systems on roofs, combined with a heat pump, can make part of the built environment energy-neutral.

Solar heat can provide 10% of total heat demand in the built environment, utilities, agriculture, and industry. We’ve done research on the use of solar energy as a heat source. You can read about the problem areas and specific recommendations for making the best use of solar heat in an exploratory study (in Dutch) (pdf).

Previous research (pdf)shows that PV-T modules should harmonise optically with a building in terms of colour pattern and size. Making the built environment energy-neutral will then become a good market opportunity for PV-T. We’ve demonstrated this in aesthetic façades with solar modules and with a heat-absorbing paint on façade elements.

We’ve designed 3 PV-T systems together with Eindhoven University of Technology and a large number of companies. We did this work at our SolarBEAT research site. The systems were then built and tested in simulations in a lab environment. We use the results to calculate the business case for PV-T systems.