Bankability of Solar Plants: Impact of harsh climates

The PV market continues growing, but not in the mild climate European countries. “2015 Worlwide Solar Demand to grow 16.5%, Emerging markets growth to surpass 40%”, states an article published last 2014-12-15.

New solar demand goes now to places with much severe and diverse climatic conditions: Mexico, China, the US, India, Chile, the Caribbean, Africa, UAE, etc.

For banks and investors, the learning curve experienced in countries like Germany, Italy or Spain does not work any longer.

The new countries are exposed to Climatic conditions much harder than the mild European climates. In these emerging countries new risks may be the new nightmare for financiers:

1. Deserts: Extreme temperature, dirt and erosion due to sand storms.
2. Tropical areas: Extreme humidity and Cyclonic winds.
3. Islands: High corrosion due to salinity and humidity.
4. High mountains: UV radiation and extreme low temperatures.

All this factors are impacting to the Technology risk, not covered by previous experience. It covers all dimensions: PV module, BoS (Balance of Systems), Integration and maintenance. This may be a new barrier to project finance, as this new environment affects to performance, reliability and service life of the whole system. Previous experience is not bankable now and the PV industry need to provide assurance to recover confidence.

Failure modes can be accelerated due to these conditions. Simple insulation problems due to humidity can stop power inverters and cause significant loss of electricity production.

Potential induced degradation (PID) due to high system voltage in hot-humid climates is a major performance issue for PV modules. The degradation mechanism is affecting up to 30% of power loss.

Module manufacturers claim to have solved the PID issue, but is this still valid in hot-humid countries?

This technology risk is well described in the "Accelerated lifetime testing of photovoltaic modules" report from Solar America Board for Codes and Standards.

Köppen-Geiger climate classification is perhaps the most widely used worldwide map in many topics, from climate change to agriculture and biology. Every place in the world is classified with a three letters code, resulting in 31 classified climates. For example "BWh" code means Arid (B), Desert (W) and Hot arid (h).

Dividing the earth in 1º elements, in longitude and latitude, we have developed the following interactive graph (please be aware the world is divided in 360x180 points, equals to 65700 data points for the interactive graph). It is possible to zoom-in an specific area of interest and to filter different climates to better visualize the areas of the world with an specific combination of climatic conditions of interest.

Knowing the specific climatic conditions of a particular site, it is possible to develop mathematical models to predict the expected life of a component (pv module, inverter, the whole pv plant) and the performance degradation. IEC 62506 is an International Standard the provides guidance on the application of mathematical models to assess impact of climatic conditions on the expected life of a component.

The challenge is there, but there are ways to assess the risk and provide mitigation actions. This is to ensure than solar plants are still bankable under extreme weather conditions.

I would appreciate if you share data on failures and degradation in harsh climates, in order to improve the inputs to our models. You will find more insights in the following group: