Dirk Tegtmeyer is a regular contributor to PES, and his valued input acts as a bellweather for the health of Ingenieurbüro Mencke & Tegtmeyer GmbH and the PV industry at large. We caught up with the German executive once again for another exclusive interview.
PES: Welcome back to the magazine. How has business been since we last spoke?
Dirk Tegtmeyer: Our sales remain stable, yet at a low level – around 50% of our best year, 2012. We have growing business in customised projects, which means that our engineering work is rising. For example, during the few last months we have built several measuring test stands for automatically measuring I-V curves of PV modules outdoors. That implements a complete I-V curve measuring system with remotely controllable PC and meteorological station for collecting data of PV modules as well as of weather conditions. So the customer can get the specific performance of different PV modules over the seasons for his location.
We built stations using one I-V curve analyser, with switching matrix for testing I-V curves one after the other (that takes three seconds for every module) and also stations with multiple I-V curve analysers, that are measuring the I-V curves of the PV modules connected at the same time (synchronous mode).
For the time the modules are not I-V curve traced they are switched to a load to hold the modules in work. The most cost-effective solution are working points resistances, but also MPP-tracking units can be used.
