PVs Also Need Maintenance

Clean energy is the new buzzword. The moment you search for images of “Clean Energy”, “Sustainable Power” etc on Google, your computer screen is splashed with beautiful images of indigo blue skies with green grassy fields beneath. A large number of these images will show a bright sun shining over neatly arranged matrices of Blue-black Photovoltaic Panels. 

Yes harvesting the sun’s energy from sunrise to sunset through Photovoltaic panels is the new sunrise industry (pun not intended). Any advocate of solar energy will list out the advantages of solar power as:- 
  • The sun rays are free.
  • It will reduce your power bills.
  • It is for a sustainable and happy future for your children.
  • It does not have moving components.
  • It is “Maintenance Free”. 
I agree with all but the last reason, that is said above. An engineering system whether it has moving parts or not, cannot be maintenance free. It may need comparatively lesser maintenance, but it cannot be maintenance free
To understand this, we need to be very clear about the following:- 
  • What is maintenance?
  • How does a Photovoltaic System function? 

Maintenance does not only mean inspecting moving parts and replacing old or damaged parts with greasy hands. An image that has been developed over the years. Maintenance basically means a process by which a component, part or sub-system is inspected from time to time and corrective action like repairs or replacements undertaken based on the inspection. Alternately, the condition of the system may be monitored based on measurement of various parameters and maintenance undertaken when required. 
A Photovoltaic system comprises, like any other engineering system, a number of subsystems, components and sub-assemblies. It may not be made up of moving components, but then it is exposed to the vagaries of nature, Ultra-violet radiation, heat and may be at times, arcs and flashes due to dust etc. 

Coming to how a Photovoltaic system functions. Well, the basic concept is very simple. Photons of sunlight are made incident on the Photovoltaic panel. The panel itself is made up of semiconductors, basically p-n junctions. When solar radiation is absorbed in a p-n junction diode, electron hole pairs are generated. The rate of generation is uniform when the wavelength of the solar radiation is long. Under these conditions there is a build up of positive and negative charges across the p-n junction leading to Photovoltaic effect and thus flow of current. 

Why am I discussing this? Because it is essential to understand that the voltage and current are generated in a Photovoltaic system because of the energy of the photons incident. For this, the basic requirement is that the photons should be able to reach the p-n junctions. The performance of any Photovoltaic system is extremely dependent on this. Thus, to avoid degradation of system with time, it is extremely essential that the Photovoltaic panels are clean. Dust, we know, won't allow light to pass through and reach the cells.

Other requirements of maintenance may involve:- 
  • Inspection of junctions.
  • Inspection of the frame structures for corrosion.
  • Inspection of Photovoltaic panels for cracks/ damages etc.
  • Inspection of cables for chafing, wear and degradation due to ultra-violet rays.
  • Inspection of relays.
  • Upgrading/ maintenance of SCADA software.
  • Inspection/ maintenance of batteries. 
Though the list may look small, these are human intensive activities. The enormity of the effort dawns upon the operator when we extrapolate the effort to a utility scale Solar Power Plant spread over a few square kilometres and comprising a few thousand panels.

With increasing competition and cut throat reverse auction in vogue, maintenance cost becomes extremely important. Also, these maintainers are required periodically; hence, a good option is to outsource the maintenance activities, which are not core to the profit from the Plant. 

This is where organisations like Adler Technoserve come into picture. We comprise a group of professionals with backgrounds in engineering. Our associates have more than 70 years cumulative experience in design operation and maintenance of technical systems. They have worked with global as well as Indian companies and have a wide experience in operations and maintenance. 

We aim to study and resolve the various technical challenges faced by Solar Power Plants. We not only provide Technical Solutions but also hand hold companies in implementing them. We can be contacted at rajesh@adlertechnoserve.com, or +91-9899345747. You can also browse are services at www.adlertechnoserve.com

Cdr Rajesh Sinha (Retd) is a ‘Mechanical Engineer’, has a Post Graduation in ‘Nuclear Technology’ and an MBA in ‘Technology Management’. He is Founder of Adler Technoserve Pvt Ltd a company working in the field of technical and business solutions and corporate training.