Direction and inclination

Even in the mild and wet climate of the Low Countries in northwestern Europe and in spite of Holland's northern latitude (50-53 degrees north), there is especially in the summer sufficient sunshine to generate significant amounts of electricity through photovoltaic panels. Solar panels need to catch as much sunshine as possible. Because it can be pretty windy in Holland, solar panels need to be firmly attached to skewed roofs, or they are placed tilted towards the sun on heavy racks on flat roofs. On the roof of my own home (picture lower right), each of the six panels is about one square meter in size and produces in theory 100 Watts of electricity @ top performance (100 Wp panels). However, the maximum recorded real-life output of the assembly on, let's say noon on a bright cold spring day, is just over 400 Watts. Every year my panels 'harvest' 420 kWh.
	4 PV panels mounted on metal strips (on top of the tiles)
It would be wonderful to have panels being all day aimed at the sun. Such sun-tracking panels exist! They are for instance made by DEGERenergie. The secret of these panels is that they are mounted on a pole. Small automatically programmed stepping motors rotate and incline the panels, and because of this the panels can therefore all day be aimed at the sun, maximizing the production of electricity.
	4 PV panels, each in its own frame, on a flat roof
The best orientation for solar panels in Holland is looking south-southwest (between 40 degrees SW and 30 degrees SE), and under an inclination (angle with the horizontal plane) of 20-50 degrees (best is 36 degrees). There should be, of course, no trees or high buildings blocking exposure to the sun. When a house has a tilted roof, a compass is needed to determine the exact orientation of the roof to the sun. A deviation until approximately 30 degrees will reduce peak performance somewhat. If the roof is more than 30 degrees off the above limits of the best orientation, then the total performance will be severely limited
	6 PV panels mounted in a frame, attached firmly on a tilted roof (tiles were removed)

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