A solar tube system is only as good as its dome. If the dome, or covering, does not capture the maximum amount of daylight available the how can it deliver the maximum amount of light to your room. All Solarspot domes are precision moulded from non-yellowing, impact resistant acrylic to provide maximum light transmittance, 95%, the highest on the market. Compared this to the efficiency of some polycarbonate domes from companies like Solatube and you may be surprised to hear that they are as low as only 74% efficient. Solarspot domes meet all building regulations for fire. You may be told that you must have a polycarbonate dome on your roof to meet these regulations but this is only the case if the dome (glazed area) exceeds a roof to glazing ratio of 5:1. In order to achieve this figure you would need to fit over 40 D-25 systems into the roof of a 10sqm room, when you would only require one.
Acrylic, PMMA or Plexiglass as it’s sometimes known has a much greater light transmittance than polycarbonate. In addition, polycarbonate is not stable when exposed to the UV rays present in daylight. Independent tests from the BRE have shown that domes from companies like Solatube go cloudy and yellow in as little as four years, reducing an already poor performance by a further 10%.
Capturing more light - the RIR Light Funnel
Unlike any other system on the market, every Solarspot has active light capture technology mounted in the top of the tube harvest the maximum possible available daylight. The patented RIR technology works in three ways; Low level light, early morning, later in the afternoon, is redirected into the tube at a steep angle to force it through the tube more efficiently so less energy (daylight) is lost. In direct, overhead light, the RIR ‘funnels’ the light to maximise its passage through the tube without obstructing and light as happens in moulded domes – as with Solatube and Sunpipe. And on over-cast days, light hits the dome from all angles so the RIR allows light from behind the dome to pass through whilst changing the angle to improve efficiency even more.
On cloudy days, light hits the dome from all angles. The crystal-clear dome and RIR® lens combine to ensure that the maximum amount of light is captured regardless of the conditions helping to guarantee more light into your home than any other light pipe system.
When the sun is above the vast majority of the light passes straight into the mouth of the tube whilst direct light that hits the back of the dome is captured and reflected in by the RIR® for maximum efficiency.
At the beginning and end of the day, and during winter months, light hits the dome from a low angle. The RIR® captures this light to ensure that the system is delivering the maximum performance all day long and throughout the year. The RIR also has the same effect when the dome is mounted on a north-facing roof, capturing light that is lost on other systems.
Not everyone had the luxury of a south-facing roof. This is no problem for the Solarspot as the RIR® lens captures light that casts across the roof and redirects down into the tube, and room below. This means that even north facing rooms can be bathed in beautiful, direct sunlight.
Even on a north-facing roof the RIR light capture lens redirects sunlight down into the mouth of the tube.
Convas for condensation protection and thermal efficiency
An element of condensation is present in all solar tube systems but unlike all other systems that deploy their double-glazed lenses at the bottom of the system, allowing for potential condensation to form on the inside of the tube wall, the Solarspot condensation lens (Convas) is located at the top of the tube. This means any condensation that does form is restricted and managed in the dome without any risk of contamination of the tube wall.
Another benefit of the Convas lens is to increase the thermal efficiency of the unit by providing an air-tight seal and creating a triple-glazed system. In addition, the Convas lens provides another layer of protection for the reflective tubing, which can be damaged by UV rays if they are not screened out.