Farm

Efficiency

Solar Tracker Farm

Possibilities and Limitations

Optimal distribution of Solar Trackers on a solar farm and adjustment of construction parameters.

The main difference between a freestanding solar tracker and a neighboring tracker farm is in the distance from any objects that can cast a shadow on the work surface. When there is no shadows then only weather conditions and construction restrictions affect the scale of production. So far, many centers as well as we have confirmed that the annual capacity of a freestanding set of photovoltaic panels on Two-Axis Solar Trackers is 40% higher than those mounted on fixed constructions. Can this result also be maintained in farm installations?

Assumptions and
conditions

Achieving the maximum performance of the set is only possible if certain conditions are met;

  • The construction throughout the whole day is not shaded.

    No bends around the rack (distance from the nearest object depends on its height).

  • There is no limitation in the rotation of the structure.

    In the range of full 360 degrees. Regardless of the latitude, during the year the sun radically changes its position.

  • There is no limit to the tilt of the structure.

    In the range of 0-90 degrees - many cloudy days require that the work plane be able to set in full range.

  • Permissible curvature / deflection of the working surface of the structure is not more than 2 degrees.

    Structures have their resilience and this fact should be taken into account when calculating actual performance.

  • The number of days simultaneously sunny and with a wind force above 60km / h is less than 10% compared to all sunny days a year.

    Always take into account the wind force when controlling the tilt of the work plane. Slopes have a significant impact on performance.

Real solar farm performance.

Considering the above, let's try to analyze the actual profit from the use of solar trackers in the construction of a solar farm. Rei Solar Tracker is structurally prepared to work in both planes without restrictions that would affect the performance, these 2 points are met and we will not dwell too much on them. Rei Solar Tracker allows you to mount the wide working surfaces and providing a 3 point stance significantly reduces the deflection of the working plane, it is easily possible to obtain deflection of the structure below 2 degrees.

Mutual
shading

How to arrange adjacent trackers? What to look for when designing a farm?

In the case of farm design, an important parameter is the ratio of power obtained from the entire installation to the surface it occupies.                 In most locations, access to land is limited, most investors want to allocate as little space as possible for installation.

  • Everywhere on earth the sun rises and sets every day in a different place so the distances between trackers measured from north to south or from east to west are, however, similar.

  • Also in the tropics, building a honeycomb mesh does not significantly reduce the problem of shading.

  • The most important parameter that affects the length of the shadow is the height of the working surface.

% Sets Arrangement ...

Attention; Not the height of the structure from the ground to the tallest element but the height of the work surface itself is significant. This surface changes its height depending on the height of the sun above the horizon.

Although the first rays of the rising sun fall on the work surface at an angle of about 9 degrees above the horizon                      photovoltaic panels will generate an significant voltage for the inverter when the sun is radiating from a height of about 20 degrees.                      Of course, these data change slightly depending on the geographical position, as well as the parameters of the inverter and solar panels.

Initial effective height of the sun ...

Based on these data, we know what the actual height of the work surface of our stand will be and thus the length of the shadow. We can conclude that ideally it will be if the racks are 20 m from the center of the structure. What happens if we want to bet a larger amount of sets on the same land?

Since the Rei Solar Tracker can be installed on the platform, we've put several constructions on trailers and made measurements in various settings. It turns out that the optimal parameters of the farm are also dependent on the proportion of the working surface. Here again the Rei Solar Tracker design allowed us to do anything surface forming. Even a very wide plane is stably maintained and controlled to the sun. Below is a summary of the results obtained on the basis of our measurements.

Comparison of selected sets ...

Summary of the analysis

  • By choosing the right proportions of the Rei Solar Trackery working plane and their optimal density, we can fit about 1MW solar farm on an area of about 18,000 m2 (1.8 ha).
  • The photovoltaic farm using Rei Solar Tracker is able to produce annually 30% more energy than a farm of the same power in which solar panels are on fixed constructions.
  • Improper proportion selection of the working surface to the distance between solar trackers can significantly reduce the profitability of the investment.

Although it is possible to increase the farm's efficiency from a + 30% to parameters similar to free-standing trackers approaching 40%, it should be remembered that such a farm will occupy a much larger area and not always the value of land will justify that decisions.

Consider if you can improve the efficiency of your installation without changing the solar panels and inverter. And most importantly, producing less waste in the future.