The main design consideration: Integral or differential installation

The first project decision is if you like an integral or differential solution. Both strategies can be feasible, but they are connected with different types of compromises.
Your situation will decide which way to go.

Integral solar energy installations

Integral solutions are appropriate if there are fixed system boundaries (i.e. your needs are constant over a long period of time) and it is practical possible to coordinate included functions, so that one solution can fulfill more than one function. In the solar energy branch, Building Integrated Solar Panels are the typical example. For example, if you are planning to build (or rebuild) some type of facility, and are just in the initial planning phrase, it could be feasible to discuss the options with the architect; how one can replace traditional wall- and roof-materials with solar panels. The standard solar panels are externally made of glass sheets and aluminum profiles, which are basically very good exterior materials (low corrosion, low maintenance, very smooth surface, easy to clean, easy to join with glue). The complete facility design is then aligned so that the best possible matches between the needed functions are fulfilled by common means. E.g. the roof surface or the south-side wall of the house may be tilted south with a quite large angle, (optimal about 45-55 deg in case of a Nordic country). Usually, the integral approach gives some compromises in the included functions, but anyway, it can be feasible due to material savings.

Building integrated solar collectors are in first hand fixed systems, i.e. no mechanical tracking. Standard solar cell modules are normally too large to be able to be used as both durable building-covering and a sun-tracking energy source. Standard solar cell modules also give significant limitations in the building design and limit the appearance of elegance. An elegant Building Integrated Solar Panel System must be built from small single solar cells, which can be mechanical actuated, and even connected with flexible material, to form continuous surfaces. It must be noted, that standard crystalline silicone solar modules (mono-crystalline or poly-crystalline) made of glass sheets and aluminum profiles are not normally used as integrated building elements, like roof covering, but as extra layer of material outside the façade or on top of a standard roof. Using this type of photovoltaic modules for replacing bricks, sheet metal and roof tile is very experimental.

Differential solar energy installations

The standard approach to anything that is new and unsafe is to keep it separate. The main benefit with the differential strategy is that different parts of the system/facility do not depend on each other, which reduces risks and makes the planning much simpler, since each function of the system can be planned individually. Efficiency will be improved by reducing losses, improve focus, introduce sun-tracking, and reduce the footprint to a minimum. In this strategy, we want to keep the solar collectors together in a group, so that the occupied space is as small as possible. The shorter the distance between the energy source and the end-effector are, the better. The lesser the solar energy installation affects the surroundings (except its output, the electrical power), the better.

An existing facility does not need to be radically rebuilt to include new solar cells with a differential setup. With appropriate frames, small solar cells can be mounted on roofs that are not tilting south. Most existing solar energy installations worldwide are differential in their structure. I.e. they are added as extra material on top of existing structure - or beside existing structure - for deliver the sun-energy-gathering function only.

The sketches on solar trackers below describe differential designs. With solar tracking, the footprint of the energy plant (with a fixed annual output) will decrease compared with a fixed mounted system.

NiBI can be your partner in developing customized solar energy collectors mountings, both integral and differential setups.

Our area of specialization is the design of solar-trackers, heliostats and solar cell mounting solutions for special conditions, e.g. industrial applications, greenhouses, day-light heliostats for public buildings, and street lighting.