Towards an era of megawatts: Challenges facing quality and reliability

By Karl-Heinz Remmers, CEO of Solarpraxis AG

Dear Readers,

In 1992, when my former company, consisting of just two university students, was trying to set up its first PV plant with an output of 5 kilowatt peak (kWp), it was faced with significant technical and financial obstacles. The regional energy supplier, for example, had concerns about a possible negative effect the plant might have on the network. Back then, it was only thanks to a courageous regional director at Sparkasse that we were able to obtain the 70,000 euros needed to pre-finance the plant. Once hooked up to the network, the then unreliable networks played numerous tricks on us that we were fortunate to overcome.

The small plants that were in operation during those times provided information that significantly advanced existing technologies. In 2001, the first commercial megawatt peak (MWp) plant was launched in Germany. Another six years later, the solar boom in Spain commenced the era of the MWp solar energy plants that are now playing an increasingly larger role in photovoltaics in countries such as the USA, South Korea, China, and once more in Germany. Germany, and therefore also the Solarpraxis engineering team, will again soon boast the world's largest plant with 88 MWp.

In the past, the challenges revolved around obtaining a few thousand euros, but now, the financing volumes for MWp projects stretch to several hundred million euros. As a result, the financing volumes equal those of the traditional energy production segment. Quality and reliability requirements grow with every increase in size, especially with regard to increased plant availability, which has a direct effect on the continuously growing efficiency of the plants (performance ratio).

Increasingly detailed concepts improve the monitoring and maintenance processes of finished plants and make them more precise. The quality assessment of products and materials used, and comprehensive planning discussions regarding the calculation of profits, statics, inverters, their circuitry concepts and the cabling of all components continue to present new challenges.

In order to keep up with installation cost reductions for modules and inverters, we are becoming increasingly successful in optimizing installation and adjusting sub-products that, as yet, do not quite fit precisely. A good example of this is the intersection between the module and mounting rack. Once launched, protection against theft and optimized commercial operations also become important issues so that plants can be used in a worthwhile manner even after the normal operating duration of 20 years.

This brochure addresses all these aspects. It is intended as a guide to and an overview of the industry, but is also aimed at responsible policy makers, and seeks to clarify the economic importance of large PV plants in assisting with the establishment of the appropriate framework conditions.

We would like to thank all the companies who helped create this brochure by providing special expertise and suitable products, and hope you will enjoy reading it!

Karl- Heinz Remmers