Siting for Solar Photovoltaic Array

Output from SPV array can be improved to the optimum level by taking care of the following:-

  1. SPV array should be as close to the control room as possible to avoid unnecessary voltage drop/power loss.
  2. A complete SPV array consists of multiple structures with each structure supporting some SPV panels. All structures SPV output are connected in series or parallel as required, should be located as close to each other as possible to avoid voltage drop. For example, A typical installation of 3600W SPV system consists of 4 similar structures each of 900W (12 nos of 12V 75W SPV module with 4 panels connected in series and 3 such series strings connected in parallel) as shown in fig. No. A. Please note that our structure is located as close to other structure as possible leaving sufficient gap for servicing.
  3. While each structure should be close to the next, between structures, adequate space should be allowed for free movement for servicing.
  4. SPV structures should be designed in such a way that all solar panels can be easily reached by human hand for regular cleaning.
  5. In India all the structures with their solar panels fitted on them should be facing magnetic south. Solar panels should face true south in northern hemisphere and true north in southern hemisphere. For the purpose of finding the direction, magnetic compass has to be used. Photographs of a common magnetic compass is given.
  6. Each structure should be facing south but tilted at an angle from the horizontal ground level. They should be tilted from the horizontal at a degree equal to the latitude of the site location.
  7. All the structure should be located in such a way that no shadows of any adjoining trees or building or structures fall on any solar panel at any time of the day.
  8. For any wind solar power plant installation, the solar panels should be located in southern most part of the site and all other installations like WTG, control room, DG installation etc will be on the northern side of the solar panels.
  9. Space between two rows of solar structures should be atleast twice of the height of the solar panel structures at the highest point of tilt. This minimum space is required to avoid shadow of one row of solar structure to fall on the row behind it.
    Solar Photovoltaic Array
  10. Similarly if there is an obstacle, on the southern side of the solar structure/modules the distance of the solar structure/module facing the obstruction should be atleast twice the height of the obstruction. Please refer Fig. No. A
  11. While installing solar panels on the tin/asbestos roof of any building, sufficient gap is to be provided between the roof and the solar panels to avoid the solar panels getting heated by the tin roof. Gaps to be provided between panels for escape of hot air.
  12. Whenever solar structure are installed on the ground, the area under & around the solar panels should be covered with small stone chips and sand to discourage growth of grass all around solar panels and also to discourage cattle. It also saves the solar modules from accidentally catching fire if there are any dry grass around it which can burn.
  13. It is best if a water tap is located in the vicinity of the SPV installation to provide water for periodic cleaning.
    Solar Photovoltaic Array
  14. Location of Electrical control room/Battery room
  15. Control room should be located as close of the WTG (wind turbine generator) and the SPV (solar photo voltaic) as possible but not so close as to cast shadow on the SPV. The control room will house the battery, wind & solar charge controllers and the inverters.
  16. The dimension of the control/battery room should be atleast 12ft X 12ft X 12ft ht. for upto 10 KW wind solar hybrid system and 12Ft X 20ft X 12ft ht for a 20KW hybrid system.
  17. The control/battery room should be well ventilated for exhausting the small amount of gas emitted by the battery bank. Preferably it should be open for using natural light to the extent possible. No other sensitive electronic equipment should be located in the same room as the battery to avoid corrosion (This includes the master controller if supplied along with wind solar diesel hybrid system. The master controller should be located in room/space outside the battery room but has to be very close to the battery bank)
  18. The control/battery room should be easily accessible for servicing.

Trouble shooting

The solar panels don't have any mechanical parts involved in it so there are no mechanical trouble shooting involved in it.

Also most of the time the solar photovoltaic panels mounting structure is fixed type and no tracking system is involved in it hence troubleshooting for the solar structure is not there.

Symptoms Possible cause Correction

1) Solar panels not giving the desired power even on bright sunny days.

1) Dusty panels

2) Loose connection at panel terminals

3) Loose connection at the controller terminals

4) Loose connection at the battery terminal

5) Batteries are fully charged or sulphated.

6) Cut in solar cables

1) Clean the panels at least once in three days.

2) Tight all the loose connections found at solar solar panels

3) Tight all the loose connections found at solar charge controller.

4) Tight all the loose connections found at battery terminals

5) Let the battery discharge or consult the battery manual from the battery manufacturer.