The primary way that solar technology can add insulation is by installing in-roof panels. These are not the same as standard photovoltaic solar panels that sit on top of the existing roof. Insulated solar in-roof panels do precisely what their name suggests. They are fitted into the roof, replacing some tiles and lying. Solar thermal technologies are a highly effective way to produce hot water. The technology has been around for a while – longer than more modern solar PV panels – yet it can be far more efficient, capturing more energy and converting it into heat for water more quickly. The. PV technology converts solar power into usable electricity, whereas solar thermal systems provide hot water. Solar thermal panels installed on a roof. Conversely, installing solar thermal panels can also help keep a house cool in the summer. The multiple layers of an in-roof solar thermal system promote airflow between each one. While.